Lateral Slits Research Articles

The study of the relationship between unicuspid aortic valve insufficiency and heart disease by fluid-structure interaction modeling

Unicuspid aortic valve (UAV) is a rare congenital malformation that affects 5% of patients undergoing aortic stenosis surgery. It has two subtypes, acommissural and unicommissural. By computational modeling with the fluid-structure interaction (FSI) method, it is possible to predict diseases related to the unicuspid aortic valve and treat them before they progress. Without it, the cost and time of treatment and the risk of failure increase. Previously, only statistical studies on unicuspid valve patients and diseases caused by it had been conducted. Modeling was performed using information from articles on patients with unicuspid aortic valves. The acommissural type, without lateral slits, had the highest grade of stenosis and the highest potential for aortic dilation compared to unicommissural. In both models, an unusually high-pressure gradient occurred, which caused peak strain on the raphes and edges of the leaflets. The presence of the vortex upstream led to the acceleration and increase of calcification. The findings of this study suggest specific differences in hemodynamic characteristics and valve mechanics for different UAV phenotypes, including the severity of stenosis and leaflet strain, which may be critical for predicting subsequent aortic diseases and differential treatment strategies.

The Discovery of a New Genus of the Prosthenorchis Travassos, 1915 (Acanthocephala: Oligacanthorhynchidae) Complex in North America, with the Description of Neoprosthenorchis bifestoonatus n. gen., n. sp. from Bobcats in Louisiana

Neoprosthenorchis bifestoonatus n. gen., n. sp. (Oligacanthorhynchidae) is described from a bobcat, Lynx rufus (Schreber) (Felidae) in Louisiana. Neoprosthenorchis is the third of the genera comprising the Prosthenorchis Travassos, 1915 complex and the first in North America. The other two genera are Prosthenorchis from primates in South America and Felidae in Africa and Paraprosthenorchis Amin, Ha, Heckmann 2008 from Manidae in Vietnam. Neoprosthenorchis n. gen. is distinguished from the other genera of the complex by having two conspicuous sets of festoons at the anterior end of the trunk. The first set is made up of long and narrow vertical ribs encircling the anterior trunk and the overlaying second is a prominent horizontal undulating band. The festoons of Neoprothenorchis bifestoonatus n. gen., n. sp., especially the second set, are unique and different from all others previously described. Species in the two other genera normally have one crown of vertically ribbed festoons each. In addition, the North American species N. bifestoonatus also has a non-ornate longer than wide proboscis with 12 rows of 3 hooks with lateral slits, each without barbs but with simple heart-shaped roots and slight anterior manubria. A detailed description with line drawings and light microscope images along with the history of the concept of Prosthenorchis are provided.

Lysimachia caloneura (Primulaceae), a New Species from Hunan, China

Lysimachia caloneura G. Hao, X.L. Yu & A. Liu sp. nova (Primulaceae) is described and illustrated from Hunan, China. In general morphology it resembles the species in subgen. Lysimachia sect. Nummularia ser. Drymarifoliae, characterized by leaves with black glandular punctuations or striations, yellow corolla, filaments being longer than anthers and basally connate into a short tube, and a dorsifixed anther opening by lateral slits. Lysimachia caloneura is to some extent similar to L. patungensis, but differs from the latter by its tiny size and by having a strikingly dark green abaxial leaf surface and narrow light green bands along the main veins on the adaxial surface.

Effect of Tread Design Changes on Tire Patch Dynamics at High Speeds Using a Dynamic Contact Force Measurement Rig

ABSTRACT The dynamic effects at the tire contact patch are one of the most difficult factors of a tire to measure. Generally, only the total forces at the tire axle are captured during the tests. There are a few methods for identifying the force distribution at the tire contact patch, but most of these methods are limited to static tests or dynamic tests at slow speeds under nonrepeatable conditions, such as with vehicle testing. Because of this limitation, A&D Company, Limited has developed a tire-testing machine called the dynamic contact force testing rig (DCFR) to measure the dynamic force distribution at the contact patch during high speeds and under reproducible conditions. Preliminary studies have shown that minute changes in shear stress and pressure distribution can be measured consistently. This study observes the dynamic force distribution in a high-performance tire under a variety of test conditions: varying normal load, speed, slip angle, and slip ratio. The tire tread was altered manually by siping additional longitudinal and lateral slits in the existing tread pattern. The tests were repeated for each tread pattern: stock tire tread, additional longitudinal slits, and additional lateral slits. The change in force distribution was compared along the longitudinal, lateral, and vertical axes. The results showed how small changes in tread design can influence tire performance. This article is a preliminary study, primarily investigating the capabilities of the DCFR while investigating basic observable trends in force distribution.

<p><strong><em>Lysimachia daqiaoensis</em></strong><strong> (Primulaceae), a new cave species from Guangdong, China</strong></p>

Lysimachia daqiaoensis, a new species of Primulaceae endemic to a limestone cave in northern Guangdong, China, is described and illustrated. It is most similar to L. rupestris in having rosette leaves and being glabrous all over the plant, but it differs from the latter by absence (vs. presence) of stolon, flowers in racemose and solitary (vs. solitary only), and anthers shorter and dorsifixed with opening by lateral slits (vs. longer and basifixed with opening by apical pores).

Lateral slit delivery of bone marrow stromal cells enhances regeneration in the decellularized allograft flexor tendon

Background/objectiveStem cell–based therapy has been applied to accelerate the revitalization of allograft tendon into a viable and functional tendon. Although many authors have proposed different methods to help the seeded stem cell distribution in the decellularized allograft, limited success has been achieved as tendon is a high dense connective tissue. We hypothesized that bone marrow stromal cells (BMSCs), seeded through the lateral slit, can regenerate the decellularized tendon (DCT) graft. The cell proliferation, cell viability, and tendon-specific gene expression are increased with the seeded cell density. MethodsEighty-seven flexor digitorum profundus tendons were equally and randomly divided into 6 treatment groups that were seeded with low-density (2 × 107 cells/mL) and high-density (5 × 107 cells/mL) BMSCs through lateral slits cultured for 2 and 4 weeks, DCT without cells, and fresh live tendons. Tendons were evaluated for cell distribution, cell proliferation, cell viability, gene expression of Collagen I and Collagen III, tenogenic markers, and MMPs. ResultsHistologic evaluation revealed BMSCs distributed from the lateral slit to the whole DCT. BMSCs were proliferated and kept viable in lateral slit decellularized tendon (LSDCT) in both seeded cell density groups after 2 and 4 weeks of culture. However, no significant differences in the cell proliferation between both cell density groups at 2 and 4 weeks of culture were observed. The lowest cell viability was found in the high-density group after 4 weeks of culture. BMSCs in LSDCT showed a significant tendency of higher gene expression of Collagen I, Collagen III, tenascin C, MMP2, MMP9, and MMP13 compared to normal tendons in both cell density groups at 2 and 4 weeks of culture. ConclusionBMSCs proliferated and remained viable after 2 and 4 weeks of culture with distribution throughout the lateral slits. Lateral slit preparation allows for the effective delivery and maintenance of mesenchymal cells with proliferation and generating a tenogenic behaviour of DCT in both the low and high cell densities in an in vitro model. The translation potential of this articleRevitalizing the implanted decellularized allograft is important for clinical application. In this study, we demonstrated that the DCT, with lateral slits, could harbour the seeded stem cell and stimulate proliferation with collagen synthesis. This evidence was presented for clinical application of the lateral slit technique, in DCT grafts, which would repopulate the seeded BMSCs during tendon and ligament reconstruction.

The revitalisation of flexor tendon allografts with bone marrow stromal cells and mechanical stimulation

ObjectivesThe present study describes a novel technique for revitalising allogenic intrasynovial tendons by combining cell-based therapy and mechanical stimulation in an ex vivo canine model.MethodsSpecifically, canine flexor digitorum profundus tendons were used for this study and were divided into the following groups: (1) untreated, unprocessed normal tendon; (2) decellularised tendon; (3) bone marrow stromal cell (BMSC)-seeded tendon; and (4) BMSC-seeded and cyclically stretched tendon. Lateral slits were introduced on the tendon to facilitate cell seeding. Tendons from all four study groups were distracted by a servohydraulic testing machine. Tensile force and displacement data were continuously recorded at a sample rate of 20 Hz until 200 Newton of force was reached. Before testing, the cross-sectional dimensions of each tendon were measured with a digital caliper. Young’s modulus was calculated from the slope of the linear region of the stress-strain curve. The BMSCs were labeled for histological and cell viability evaluation on the decellularized tendon scaffold under a confocal microscope. Gene expression levels of selected extracellular matrix tendon growth factor genes were measured. Results were reported as mean ± SD and data was analyzed with one-way ANOVAs followed by Tukey’s post hoc multiple-comparison test.ResultsWe observed no significant difference in cross-sectional area or in Young’s modulus among the four study groups. In addition, histological sections showed that the BMSCs were aligned well and viable on the tendon slices after two-week culture in groups three and four. Expression levels of several extracellular matrix tendon growth factors, including collagen type I, collagen type III, and matrix metalloproteinase were significantly higher in group four than in group three (p < 0.05).ConclusionLateral slits introduced into de-cellularised tendon is a promising method of delivery of BMSCs without compromising cell viability and tendon mechanical properties. In addition, mechanical stimulation of a cell-seeded tendon can promote cell proliferation and enhance expression of collagen types I and III in vitro.Cite this article: J. H. Wu, A. R. Thoreson, A. Gingery, K. N. An, S. L. Moran, P. C. Amadio, C. Zhao. The revitalisation of flexor tendon allografts with bone marrow stromal cells and mechanical stimulation: An ex vivo model revitalising flexor tendon allografts. Bone Joint Res 2017;6:179–185. DOI: 10.1302/2046-3758.63.BJR-2016-0207.R1.

New Middle Cambrian palaeoscolecid sclerites of Hadimopanella oezgueli from the Cantabrian Mountains, northern Spain

A new assemblage of palaeoscolecid sclerites preserving all the details of the (para)species Hadimopanella oezgueli Gedik, 1977, including characteristic ornamentation, has been found in the Middle Cambrian Genestosa Member (Oville Formation) of the Cantabrian Mountains, northern Spain. The assemblage of sclerites shows a great morphological variability enabling emendation of its diagnosis. Some of them exhibit erosive facets as a result of reworking preceding definitive burial. One key specimen has lateral slits along the marginal brim, which represent a crown of eroded tubercles, and may be classified out the (para) genus Hadimopanella.

Description ofMoniliformis kalahariensis(Acanthocephala: Moniliformidae) from the South African Hedgehog,Atelerix frontalis(Erinaceidae) in South Africa

Moniliformis kalahariensis Meyer, 1931 (Moniliformida Schmidt, 1972: Moniliformidae Van Cleave, 1924) is redescribed from long, unsegmented juveniles and pseudosegmented mature adults collected from the South African hedgehog Atelerix frontalis Smith, 1831 (Erinaceidae) in South Africa. The species has not been taxonomically treated since Meyer's original description of only segmented adults from the same host, A. frontalis, as well as from the unusual host, the Namaqua sandgrouse, Pterocles namaqua (Gmelin, 1789) (Pteroclididae), in Botswana and from cystacanths from Blattella (Phyllodromia) germanica Linnaeus, 1767 (Blattidae Karny, 1908) in Bombay, India. Despite the generous space Meyer devoted to the description of mature adults of M. kalahariensis in 1931, and his shorter description in 1932, both accounts lacked considerable important information. We examined some of Meyer's original adults and cystacanths from Berlin's Museum fur Naturkunde by optical microscopy and by scanning electron microscopy (SEM). Meyer did not measure or illustrate the proboscis hooks but reported 14 hook rows with 9-10 hooks each in his adult and cystacanth specimens. The proboscis of our juvenile and adult specimens from South Africa had 16 hook rows each with 9-11 hooks. One adult from Meyer's specimens that we examined using SEM had at least 16 proboscis hook rows, and one of his cystacanths had 14 hook rows each with 10-12 hooks. Our report provides new illustrations and morphometric data of the long juvenile and mature adults and gives the full range of measurements of proboscis armature. We further describe, for the first time, the 2 apical pores on the proboscis in all stages; the proboscis hooks and their lateral slits and the spiniform hooks in adult worms; hook roots; the reproductive system in both males and females (only the size and placement of testes were reported and an egg was illustrated by Meyer in 1931 and 1932); sensory pores; and the sensory plates near the posterior end of adult males. Lastly, we also describe the large unsegmented juveniles to which Meyer made no reference.

First Report of Juneberry Rust Caused by Gymnosporangium nelsonii on Juneberry in Michigan.

Amelanchier alnifolia (Nutt.) Nutt. ex M. Roem., commonly known as juneberry or Saskatoon serviceberry, was historically a widely used prairie fruit that is native to the Northern Great Plains, southern Yukon and Northwest Territories (4). While juneberry is an important fruit crop in the prairie provinces of Canada, small commercial plantings also occur throughout the northern United States (2), including Michigan. On July 18, 2009, severe rust symptoms were observed on plants in a 2-year-old field of A. alnifolia 'Northline' in Northport, MI. The plants had been sourced as seedlings from a nursery in Alberta, Canada in 2007. Signs and symptoms were present on fruits and leaves on virtually all of the plants. Symptomatic fruit were still immature, and on average, more than 70% of the fruit surface was covered with tubular, whitish aecia with conspicuous orange aeciospores. Portions of twigs also showed fusiform swellings (1 to 3 cm long) covered with aecia. Aecia were hypophyllous, fructicolous and caulicolous, roestelioid, and 2 to 4 mm high. The peridium was cylindric and tapering toward the apex, dehiscent at the apex, retaining a tubular shape for a long time and at times becoming lacerated on the sides with age. Peridial cells were linear rhomboidal, 50 to 105 μm long, hyaline to brownish, outer walls smooth, inner walls with small papillae, and side walls delicately verrucose-rugose with elongate papillae having variable lengths. Aeciospores were globoid, 20 to 35 × 25 to 38 μm (average 30.7 × 32.5 μm), orange to cinnamon brown, and densely verrucose with walls 2.5 to 3.5 μm thick. On the basis of these morphological characters, the host, and comparison with a reference specimen (BPI 122010), the pathogen was identified as Gymnosporangium nelsonii Arthur (1,3). The 5' region of the 28S rDNA was sequenced (GenBank Accession No. HM591299.1), confirming the identification as a species of Gymnosporangium, one distinct from previously sequenced specimens available in GenBank. The specimen has been deposited at the U.S. National Fungus Collections (BPI 880671 and 880709). Four other species found previously on Amelanchier spp. in the Midwest differ as follows: G. clavipes and G. clavariiforme have verrucose peridial cells and different 28S rDNA sequences; G. nidus-avis has rugose peridial cells; and G. corniculans has cornute peridia that dehisce from lateral slits while apices remain intact and verrucose peridial walls with verrucae on the side walls (1). The infection was likely caused by basidiospores originating from telia on Juniperus spp. in the area surrounding the field. However, no telia of G. nelsonii were found on junipers in the immediate vicinity. To our knowledge, this is the first report of G. nelsonii on juneberry in Michigan and the Midwest. Because of the devastating impact of this disease on fruit quality, fungicide programs have been devised for disease control and were effective in 2010. Juneberry growers in the Midwest need to be aware of this disease and monitor their crop carefully for symptoms and signs.

First Report of Gymnosporangium sabinae, European Pear Rust, on Bradford Pear in Michigan.

Bradford pear, Pyrus calleryana Decne., is well known as an ornamental plant for its flowers, leaf color in fall, and disease resistance, making it desirable as a street tree. In August and October of 2008, the aecial stage of Gymnosporangium sabinae (Dicks.) G. Winter was collected from leaves of P. calleryana in Farmington, MI (Oakland County). The one tree had foliage that was severely affected by the rust fungus. Using published descriptions of G. sabinae as the synonym of G. fuscum, type of the genus Gymnosporangium (1-4), the Michigan specimen was identified and confirmed by comparison with previously reported European and U.S. specimens (BPI 118736 and BPI 856578). The diagnostic characteristics of G. sabinae include: spermagonia epiphyllous; aecia hypophyllous, roestelioid, 3 to 6 mm high; peridium balanoid (acorn shaped), becoming elongated at maturity, pale yellow, sides opening with lateral slits but remaining attached at light brown, pointed apex; peridial cells elongated, 51 to 68 μm long, outer walls smooth, inner walls and side walls sparsely echinulate; aeciospores globose to broadly ellipsoid, somewhat angular, surface slightly coronate, 22 to 32 × 22 to 36 μm, walls orange, 3.5 to 5.5 μm thick. This species is distinguished from other species of Gymnosporangium on Pyrus by the balanoid (acorn-shaped) peridium and the late season maturation of the aecial stage (4). Telia and teliospores of G. sabinae are produced on the alternate host, various species of Juniperus sect. Sabinae, but were not observed in Michigan. The specimen from Michigan is deposited in the U.S. National Fungus Collections (BPI 878928). G. sabinae is widely distributed in Europe, extending to Asia and North Africa, but is rarely reported in North America. It was accidentally introduced into California in the aecial stage on P. communis L. and the telial stage on Juniperus chinensis L. (2), as well as introduced into Canada (British Columbia) (3,4). The only previous report of G. sabinae on P. calleryana is in Germany (1). G. sabinae is known to attack commercial pear and ornamental juniper plants in Europe, thus it seems important to prevent the further spread of this fungus in North America.

Development of Greenhouse Inoculation Procedures for Evaluation of Partial Resistance to Cercospora zeae‐maydis in Maize Inbreds

AbstractGreenhouse experiments were conducted to determine the effects of inoculation methods on incubation period, lesion length, percentage leaf area affected and sporulation of Cercospora zeae‐maydis on young maize (Zea mays L.) plants inoculated at V3 growth stage. Seedling plants were inoculated by four methods: (i) application of conidial suspension while puncturing the leaves within the whorl several times, (ii) spraying conidial suspension on leaves, (iii) placing colonized agar into lateral slits in leaves and (iv) placing colonized agar into whorls. Analysis of variance revealed a significant effect of genotype and inoculation method on several components of resistance and overall disease severity. Application of conidial suspension while puncturing the whorl was found to be the least laborious method, and it produced characteristic symptoms of gray leaf spot. Consistent trends were observed in classification of inbreds to resistant, susceptible and intermediate classes. Increasing the duration of exposure to high humidity by placing plastic bags over plants for 5 days significantly increased disease severity (P ≤ 0.001). Cercospora zeae‐maydis produced conidia in all the lesions examined. Spore production was generally most abundant in lesions on susceptible inbreds that displayed necrotic lesion types (LT) and least abundant in lesions on resistant inbreds that were characterized by chlorotic and fleck LTs. The results demonstrated that inoculations in the greenhouse can provide an indication of inbred responses to C. zeae‐maydis and may be useful in evaluating resistance and in studies of host–pathogen interactions.

UV radiation blocking compounds in the eye of the cuttlefish Sepia officinalis.

scribed as the respiratory current (1), shows that when the book gills are active, the lateral slits entrain dye ventrally and dorsally. In both cases, dye passes the flabella. The flabella are therefore situated in the respiratory current where they can monitor chemical stimuli drawn in from a distance. However, when the last pair of legs, known as the pusher legs, are active and the book gills are inactive, these slits can serve as expulsion sites. The book gills were also able to entrain dye placed within 2 cm lateral to the opisthosoma. Limulus spends time with its prosoma burrowed in the sand (4); as a result, we hypothesize that the flabella allow the animal to sense chemical signals in its environment while partially buried. Both currents described above are expelled posteriorly under the telson when the book gills are active. Currents can be reversed and dye forced out the flare, however, when an animal flaps its opisthosoma and telson forward.

Two New Species of Chamaedorea (Arecaceae)

Chamaedorea ponderosa from Panama and C. christinae from Colombia are named and described as new, and compared with related taxa. Chamaedorea includes over 100 species of small, dioecious, pleonanthic, understory palms restricted to neotropical, mostly moist or wet, primary rain and cloud forests from eastern and western Mexico to northern Bolivia. The genus is most diverse in wet mountain forests from 800 to 1500 m elevation. The mountainous area of southern Mexico and adjacent Guatemala is the primary center of distribution; a secondary center is the mountainous area shared by Costa Rica and Panama. Since the publication of a monograph of Chamaedorea (Hodel, 1992a) and subsequent articles adding several new species (Hodel, 1992b, 1995, 1996; Hodel et al., 1995), further study has enabled me to name and describe two new species. Chamaedorea ponderosa Hodel, sp. nov. TYPE: Panama. Darien: Cerro Pirre, 2-3 mi. N of summit, 7056'N, 77042'W, 1000-1100 m, 31 Dec. 1978, Hartman 8529 (pistillate) (holotype, MO 3233713). Subgeneris Chamaedoreae (Martius) H. A. Wendland. C. murriensi Galeano affinis sed habitu grandiore, foliis nervis pluribus, inflorescentiis rhachidibus longioribus, petalis et sepalis nervis valde prominentibus, floribus masculinis dense positis, fructibus aurantiacis differt. Solitary, slender, understory palmlet to 2-4 m tall. Stem 2-2.5 cm diam., ringed, internodes 4-5 cm. Leaves simple and bifid, sometimes irregularly pinnate then usually with large terminal lobes and smaller basal pinnae, drying dark olive-green with a heavy, thick, bulky appearance; leaf base 25-30 cm long, obliquely long-open apically, tubular in basal 20-25 cm, longitudinally striated with a raised costa extending from petiole for 5-8 cm; petiole 18-35 cm long, 6-8 mm diam. at apex, 8-10 mm diam. at base, rounded and lighter green abaxially, flattened but becoming channeled toward base adaxially, longitudinally striated; rachis 40-50 cm long in simple blades, 40-60 cm long in pinnate blades, rounded and lighter green abaxially, angled and lighter green adaxially; simple blades 75 x 45-50 cm, incised apically 25 cm, acute-acuminate, with 20 elevated, sharply angled, primary nerves adaxially, these elevated abaxially, spaced 2 cm apart, 2-3 secondaries between each pair of primaries, secondaries not too conspicuous adaxially, 1-2 tertiary nerves abaxially between each pair of secondaries or a secondary and a primary, ne ves of lesser orders numerous, faint, all nerves lighter colored and except for primaries more conspicuous abaxially; pinnate blades 80-90 x 45-50 cm, pinnae 2-8(-16) per side, terminal pair to 3045 x 10-15 cm, basal pinnae 30-45 X 2.5-5.5 cm, sigmoid, falcate, long-acuminate, variously nerved depending on width but in same pattern as above. Inflorescences 50-75 cm long; peduncle 40-55 cm long, 1-1.5 cm wide at base, 3-5 mm diam. at apex; bracts 5-7, prophyll 2-4 cm long, 2nd bract 10 cm long, 3rd 25 cm long, 4th 35 cm long, 5th 15 cm long and exceeding peduncle and concealing a smaller 6'h bract to 5 cm long, bracts brown in flower, becoming tattered in fruit, obliquely open apically, longitudinally striated, basal bracts acute-acuminate, apical ones long-acuminate; rachis 12-17 cm long; staminate rachillae 931, these 25-40 cm long, 1-1.5 mm diam., drooping; pistillate rachillae 13-28, mostly simple but a few basal ones furcate, 18-25 cm long, 1.5-2 mm diam., ? spreading, peduncle and rachillae orange in fruit. Staminate flowers in ? dense spirals 2-3 mm apart, ? superficial, leaving elliptic scars 1.25-1.5 mm long, flowers in bud 2 x 2-2.75 mm; calyx 1 X 2-2.75 mm, deeply lobed 2/3 to base, prominently nerved, sepals connate in basal /3, broadly rounded apically, acute; petals 2 X 1.752 mm, ovate, valvate, acute, connate briefly basally and apically and there adnate to pistillode, corolla opening by lateral slits, prominently nerved; stamens 6, anthers 1 mm long, dorsifixed near base, filaments 0.5 mm long; pistillode 1.5 mm tall, columnar. Pistillate flowers in lax spirals 4-10 mm apart, ? superficial, leaving elliptic scars 1.75 mm long; flowers just past anthesis 2 X 3 mm; calyx 1 X 3 mm, cupular, moderately lobed, prominently nerved, sepals imbricate and/or connate in basal 12, broadly rounded apically; petals 2.5 x 3 mm, broadly obovate-spatulate, prominently nerved, imbricate in basal 3/4, rounded apically; pistil 2 X 2.5 NovoN 7: 35-37. 1997. This content downloaded from 157.55.39.181 on Thu, 29 Sep 2016 06:16:32 UTC All use subject to http://about.jstor.org/terms

Trends in Evolution of Floral Ontogeny in Cassia Sensu Stricto, Senna, and Chamaecrista (Leguminosae: Caesalpinioideae: Cassieae: Cassiinae); A Study in Convergence

Distinctions in floral ontogeny among three segregate genera (Cassia sensu stricto, Chamaecrista, and Senna) of Cassia L. support their separation. In all species studied, the order of floral organ initiation is: sepals, petals, antesepalous stamens plus carpel, and lastly antepetalous stamens. Sepal initiation is helical in all three genera, which however differ in whether the first sepal is initiated in median abaxial position (Senna), or abaxial and off-median (Cassia javanica), a rare character state among legumes. Order of petal initiation varies: helical in Senna vs. unidirectional in Cassia and Chamaecrista. Both stamen whorls are uniformly unidirectional. Intergeneric ontogenetic differences occur in phyllotaxy, inflorescence architecture, bracteole formation, overlap of initiation among organ whorls (calyx/corolla in Cassia; two stamen whorls in Chamaecrista), eccentric initiation on one side of a flower, anther attachment, anther pore structure, and precocious carpel initiation in Senna. The asymmetric corolla and androecium in Chamaecrista arise by precocious organ initiation on one side (left or right). The poricidal anther character can result from differing developmental pathways: lateral slits vs. sealing of lateral sutures; clasping hairs vs. sutural ridges; terminal pores (one or two) vs. none; and clamp layer formation internally that prevents lateral dehiscence. Genera differ in corolla aestivation patterns and in stigma type. Convergence is shown among the three genera, based on intergeneric dissimilarities in early floral ontogeny (floral position in the inflorescence, bracteole presence, position of the first sepal initiated, order of petal initiation, asymmetric initiation, overlap between whorls, anther morphology, and time of carpel initiation) resulting in similarities at anthesis (showy, mostly yellow salverform flowers, heteromorphic stamens, poricidal anther dehiscence, bee pollination, and chambered stigma).

Trends in evolution of floral ontogeny in Cassia sensu stricto, Senna, and Chamaecrista (Leguminosae: Caesalpinioideae: Cassieae: Cassiinae); a study in convergence

Distinctions in floral ontogeny among three segregate genera (Cassia sensu stricto, Chamaecrista, and Senna) of Cassia L. support their separation. In all species studied, the order of floral organ initiation is: sepals, petals, antesepalous stamens plus carpel, and lastly antepetalous stamens. Sepal initiation is helical in all three genera, which however differ in whether the first sepal is initiated in median abaxial position (Senna), or abaxial and off‐median (Cassia javanica), a rare character state among legumes. Order of petal initiation varies: helical in Senna vs. unidirectional in Cassia and Chamaecrista. Both stamen whorls are uniformly unidirectional. Intergeneric ontogenetic differences occur in phyllotaxy, inflorescence architecture, bracteole formation, overlap of initiation among organ whorls (calyx/corolla in Cassia; two stamen whorls in Chamaecrista), eccentric initiation on one side of a flower, anther attachment, anther pore structure, and precocious carpel initiation in Senna. The asymmetric corolla and androecium in Chamaecrista arise by precocious organ initiation on one side (left or right). The poricidal anther character can result from differing developmental pathways: lateral slits vs. sealing of lateral sutures; clasping hairs vs. sutural ridges; terminal pores (one or two) vs. none; and clamp layer formation internally that prevents lateral dehiscence. Genera differ in corolla aestivation patterns and in stigma type. Convergence is shown among the three genera, based on intergeneric dissimilarities in early floral ontogeny (floral position in the inflorescence, bracteole presence, position of the first sepal initiated, order of petal initiation, asymmetric initiation, overlap between whorls, anther morphology, and time of carpel initiation) resulting in similarities at anthesis (showy, mostly yellow salverform flowers, heteromorphic stamens, poricidal anther dehiscence, bee pollination, and chambered stigma).

A New Species of Oserya (Podostemaceae) from Jalisco, Mexico

A new species of Podostemaceae, Oserya longifolia, from Jalisco, Mexico, is described and illustrated. Leaf length is the most prominent feature that distinguishes this species. RESUMEN. Se describe e ilustra una especie nueva de la familia Podostemaceae, Oserya longifolia, del estado de Jalisco, M6xico. La longitud de la hoja es la caracteristica mas prominente que distingue a esta especie. Oserya Tulasne & Weddell is an American genus of six species, most recently monographed by van Royen (1954). Like all Podostemaceae, species of Oserya grow attached to rocks in swift-moving river currents. Five of the six species (O. biceps Tulasne & Weddell, O. flabelifera Tulasne & Weddell, O. minima van Royen, O. perpusilla (Went) van Royen, O. sphaerocarpa Tulasne) occur in northern Brazil and northeastern South America, while O. coulteriana Tulasne occurs in Mexico. Little is known of the geographic distributions of species of Oserya. In fact, four of the South American species are known only from the type collections. At the time of van Royen's monograph, O. coulteriana was known from few collections in the Mexican states of Jalisco and Michoacan. During our recent studies of Mexican Podostemaceae we have found this species to be relatively widespread in Colima, Nayarit, and Guerrero, in addition to Jalisco and Michoacin. A collection from southern Sinaloa is also now known (Novelo & Philbrick, unpublished). While conducting field studies of Mexican Podostemaceae, we made collections that did not correspond to any described species. These collections serve as the basis for the description of a new species, Oserya longifolia Novelo & Philbrick. serya longifolia Novelo & Philbrick, sp. nov. TYPE: Mexico. Estado de Jalisco: municipio de La Huerta, Rio Purificaci6n, 4 km al oeste de La Huerta, 19?30'N, 104?40'W, 300 m, 26 Mar. 1993, Novelo & Philbrick 1166 (holotype, MEXU; isotypes, MO, NY, WCSU). Figure 1. Herbae aquaticae plerumque caulibus stoloniferis applanatis. Folia circinata usque ad 40 cm longa; petiolus laevis; lamina repetite 2-4(-5)-divisa, divisionibus ultimis 0.3-0.6 mm latis, applanatis, apice acutis. Flores hermaphroditi, zygomorphi, pedicellati, axillares, solitarii. Tepala 3, filamentis alternata, uno in furca duorum staminum affixo. Stamina 2, andropodio portata; antherae ellipticae, dorsifixae, per 2 rimas laterales longitudinaliter dehiscentes. Ovarium 2 carpellis, 2 stylis 0.7-1.2 mm longi. Fructus 2 valvis, quaque valva 3-costata. Aquatic herbs usually with stoloniferous and flattened stems 0.8-1.0 mm diam., strongly adhering to rocks. Leaves alternate, circinate, up to 40 cm long, petiole 2-17 cm long, cylindrical, smooth, 0.7-1.6 mm diam., with a broadened base; blade 2-4(-5) divided, the ultimate divisions 0.3-0.6 mm wide, flattened, apex acute. Flowers hermaphroditic, zygomorphic, pedicellate, borne singly, axillary, protected by a spathella; spathella up to 7 mm long, thin clavate. Pedicels 3.5-8.0 mm long, elongating during anthesis, not expanded at capsule base. Tepals 3, alternate with the filaments, free, membranous, subulate, one of them attached in the fork between the two stamens; lateral tepals 0.9-1.2 mm long, medial tepal 0.7-0.9 mm long. Stamens 2, borne by an andropodium, andropodium 0.8-1.3 mm long, elongating during anthesis; filaments 1.01.8 mm long, subulate, flattened, elongating during anthesis, deciduous; anthers 0.4-0.6(-0.8) mm long, elliptic, dorsifixed, 2-celled, dehiscing longitudinally by 2 lateral slits. Ovary superior, 1.7-2.1 mm long, NovoN 5: 54-56. 1995. This content downloaded from 207.46.13.128 on Tue, 06 Sep 2016 05:39:13 UTC All use subject to http://about.jstor.org/terms Volume 5, Number 1 Novelo & Philbrick 55 1995 Oserya longifolia

A New Species of Marathrum (Podostemaceae) from Jalisco, Mexico

A new species of Podostemaceae, Marathrum rubrum, from Jalisco, Mexico, is described and illustrated. Capillaceous leaf divisions and red leaf color distinguish M. rubrum from other species. RESUMEN. Se describe e ilustra una especie nueva de la familia Podostemaceae (Marathrum rubrum) del estado de Jalisco, Mexico. Las divisiones capiliformes y el color rojizo de las hojas distinguen a M. rubrum de las otras especies. The pantropical Podostemaceae are the largest family of aquatic flowering plants. Little taxonomic work has been conducted on New World Podostemaceae since Royen's treatments (1951, 1953, 1954). Currently most species of Podostemaceae in the New World are poorly collected, taxonomic boundaries at both the specific and generic levels are unclear, and factors relating to the unusually high incidence of endemism (e.g., > 45% among New World species) are unresolved. Marathrum, one of the largest genera of Podostemaceae, is composed of 25 species occurring in tropical river rapids and waterfalls. The genus ranges from the West Indies and Mexico through Central America, to northwestern portions of South America (Royen, 1951). During field studies aimed at clarifying the taxonomy of Podostemaceae in Mexico, collections were made from Jalisco that did not correspond to any described species. These collections serve as the basis for the description of a new species, Marathrum rubrum Novelo & Philbrick. Marathrum rubrum Novelo & Philbrick, sp. nov. TYPE: Mexico. Estado de Jalisco: municipio de Cabo Corrientes, Puente Los Horcones sobre el rio, a 27 km al S de Puerto Vallarta rumbo a Chamela, 6 Mar. 1991, Novelo & Philbrick 1003 (holotype, MEXU; isotype, RSA). Figure 1. Herbae caule longo, prostrato, applanato; lamina iterum atque iterum pinnata, divisionibus ultimis capilliformibus, 2-4.5 mm longis, 0.02-0.06 mm latis, rubescentibus, apice acutis. Flores solitarii, axillares, pedicellati; pedicelli apice expanso, cupulato, cupula 1.5-2 mm diametro. Tepala triangularia, filamentis alternantia. Stamina 7-9 in verticillo, libera, pistillum cingentia. Antherae 1.52.8 mm longae. Styli liberi, conici. Fructus 4.5-5(-6) mm longus, 2 valvis, quaque 3-costata. Aquatic herbs usually with a long prostrate and flattened stem up to 1 cm diam., strongly adhering to rocks. Leaves alternate, up to 20 cm long, petiole 2.5-9 cm long, cylindrical, up to 0.8 mm diam., with a broadened base; blade repeatedly pinnate, the later divisions capillaceous, 2-4.5 mm long, 0.02-0.06 mm wide, apex acute. Flowers hermaphroditic, actinomorphic, pedicellate, borne singly, axillary, protected by a spathella; spathella 0.72 cm long, thin, clavate. Pedicels 3-5.5 cm long, elongating during anthesis, with an expanded apex forming a cuplike process around the capsule base, cup 1.5-2 mm diam., with irregular border. Tepals 0.5-0.9 mm long, triangular, alternating with the stamens. Stamens 7-9, free, in a ring surrounding the pistil; filaments 2.3-4(-9) mm long, subulate, flattened, elongating during anthesis, deciduous; anthers 1.5-2.8 mm long, sagittate, basifixed, 2-celled, dehiscing longitudinally by 2 lateral slits. Ovary superior, ellipsoid, 2-locular; styles 2, 0.6-1.5 mm long, free, conical, ovules numerous, placenta axile. Fruit 4.5-5(-6) mm long and 1.7-2.2 mm diam., 2-locular capsule, suture margins thickened; valves 2, subequal, each 3-ribbed, one of them deciduous. Seeds 0.25-0.30 mm long, 0.12-0.18 mm wide, 574 (SD 317, N = 20) per capsule, obovoid. Pollen 14.5 um (SD 0.8, N = 30) diam., tricolpate, tectum spinulose. Paratypes. MEXICO. Jalisco: Municipio de Cabo Corrientes, Rio Horcones, aprox. 17 km S de Puerto Vallarta rumbo a Chamela, 6 Feb. 1991, Novelo 979 (MEXU, RSA); Puente Los Horcones sobre el rio, a 27 km al S de Puerto Vallarta rumbo a Chamela, 6 Feb. NOVON 3: 456-458. 1993. This content downloaded from 207.46.13.111 on Tue, 09 Aug 2016 05:30:22 UTC All use subject to http://about.jstor.org/terms Volume 3, Number 4 1993 Novelo & Philbrick

Holographic real-time three-slit interferometer

A new and highly sensitive system, based on the three-slit interferometer, is described for the scanning measurement of optical path length differences over large objects. The system relieves the positional constraints of previous systems by separating the two lateral slits from the central slit using a double-exposure hologram. The lateral slit wavefronts are holographically reconstructed from an off-axis reference beam and added to light from the central slit to form a live intensity distribution pattern. Optical path length measurements can be made by comparing the magnitude of adjacent maxima as an object is translated across the central slit. The apparatus can be used for a number of practical applications including the measurement of flatness for an optical flat, thickness for transmissive or reflective films, and refractive-index differences of materials.