Drawing Tube Research Articles

A method for the study of the spatial distribution of the neuronal dendritic tree using a universal stage

The use of a microscope equipped with a universal stage with 4 rotation axes, drawing tube and photographic system for the 3-dimensional study of neuronal morphology is considered. Two-dimensional projections of the neuronal tree are obtained by rotating the stage, and the application of coordinate transformations results in a 3-dimensional mapping of neuronal topography. Algorithms used for these transformations are presented and the method applied to Golgi-impregnated neurons of the cerebral cortex of adult lizards. The advantages, limitations and sources of error of this method are discussed.

A New Species of Echinocephalus (Nematoda: Gnathostomidae) from Neotropical Stingrays with Comments on E. diazi

Echinocephalus daileyi sp. n. is described from the freshwater stingrays Potamotrygon circularis and P. hystrix in South America. It is most similar to E. diazi by virtue of possessing a gubernaculum and six postanal papillae, but may be distinguished from E. diazi and other members of the genus by possessing 30 to 34 rows of spines on the cephalic bulb, three preanal papillae, and a body 55 to 85 mm long. Specimens of E. diazi were collected from Himantura schmardae, the type host, from Cienaga Grande, Colombia, a new locality record. Based on numerical phylogenetic analysis, E. daileyi is a member of a monophyletic group including E. sinensis, E. diazi, and E. pseudouncinatus. Examination of marine and freshwater stingrays in northern South America during 1975 to 1978 revealed the presence of two species of Echinocephalus Molin, 1858. One of those species is described herein as new, and a new locality record is reported for the other. Specimens were removed from hosts, fixed in 10% formalin or in glacial acetic acid, stored in a solution of five parts glycerin and 95 parts 70% ethanol, then examined in glycerin after evaporation of the alcohol. All measurements are in micrometers unless otherwise stated, and figures were drawn with the aid of a drawing tube. Echinocephalus daileyi sp. n. (Figs. 1-12)

Chromosome Numbers of Some Mosses from Pennsylvania and New York

Chromosome numbers for eight species of mosses from Pennsylvania and New York, USA, are reported: Barbula unguiculata Hedw. (n = 13 + 1 m), Pottia truncata (Hedw.) Fiirnr. ex B.S.G. (n = 26), Aphanorrhegma serratum (J. Hook. & Wils. ex Drumm.) Sull. (n = 27), Bryum argenteum Hedw. (n = 10), Brachythecium rutabulum (Hedw.) B.S.G. (n = 12), Callicladium haldanianum (Grev.) Crum (n = 22), Pogonatum pensilvanicum (Hedw.) P.-Beauv. (n = 7), and Atrichum altecristatum (Ren. & Card.) Irel. Chromosome numbers of eight species of mosses from Pennsylvania and New York are reported below. Methods followed are those of Steere et al. (1954). Observations and drawings were made with a Wild Heerbrugg Microscope and drawing tube. Voucher specimens have been deposited in the herbarium of The Pennsylvania State University (PAC). BARBULA UNGUICULATA Hedw., n = 13 + 1 m (Fig. 1). Pennsylvania, Centre Co., campus of The Pennsylvania State University, ca. 400 m alt., on soil, Lin 003. The population studied presented a chromosome count of 13 + 1 m (Fig. 1). The minute accessory chromosome sometimes stained poorly. Of the 13 bivalents, one chromosome is extremely large, which is characteristic of the chromosome complement of this genus. Several different chromosome numbers for this species have been reported previously (fide Fritsch 1972), n = 11, 11 + 1 m, 12 + 1 m, 13, 13 + 1 m, 13 + 2 m, 14, 14 + 2 m, and 24. Messmer & Lersten (1968) report n = 14 + 2 m from a population in Iowa, but judging from their figures the chromosome number consists of 13 bivalents and 2 minute accessory chromosomes. Although the number n = 14 has been published by Smith & Newton (1967), one of the bivalents as described by them is small. Additionally, Smith and Newton also observed that one large bivalent and one medium-sized bivalent usually separate precociously. Thus, there might be two chromosome races of the species in the United States, i.e. n = 13 + 1 m and n = 13 + 2 m. POTTIA TRUNCATA (Hedw.) Fiirnr. ex B.S.G., n = 26 (Fig. 2-3). Pennsylvania, Centre Co., campus of The Pennsylvania State University, ca. 400 m alt., on soil, associated with Aphanorrhegma serratum and weeds, Lin 008. This count, n = 26, is the first report for the species reported from the United States; the number is the same as that reported by Visotskaya (1967, fide Fritsch 1972) from Russia. Other counts of P. truncata are n = 25 by Vaarama (1950) from Finland and Javorcikova & Somsakova (1967, also fide Fritsch 1972) from Czechoslovakia, and n = 20 and 52 by Smith & Newton (1967) from England and Ireland. 007-2745/81/370-374$0.65/0 This content downloaded from 207.46.13.129 on Fri, 01 Jul 2016 06:00:58 UTC All use subject to http://about.jstor.org/terms 1981] LIN: CHROMOSOME NUMBERS 371

Collections in the Farlow Herbarium: New Species ofMelanophyllumandGastrocybe, Type Studies onArmillariaandStropharia

SUMMARY Melanophyllum globisporum from Pakistan and Gastrocybe deceptiva from the United States are described as new. Type studies on Agaricus (Armillaria) melleorubens, Armillaria macrospora, Armillaria solidipes and Stropharia subcaperata are included and the new combinations Armillariella macrospora and Armillariella solidipes are proposed. In addition, lectotypes are selected for Agaricus melleorubens and Stropharia subcaperata. The following account of new species, microscopic descriptions of type specimens and selection of lectotypes is a result of the current systematic reorganization of the general collection of Hymenomycetes at the Farlow Herbarium. Methods of study were outlined previously in Baroni (1976, 1981). Measurements of basidiospores include the hilar appendix, except in Gastrocybe deceptiva where the measurements are given separately. Drawings were made with the aid of a Wild drawing tube. Color notations were taken from Kornerup and Wanscher (1978) and refer to the plate number-vertical row letter-horizontal row number, e.g., 6E-F4.

Real-Time Morphometric Analysis of Type I and Type II Fibers in Cryostat Sections of Human Muscle Biopsies

Summary The application of a computer-assisted morphometry technique for the analysis of muscle biopsies is described. This method involves digitizing the contours of muscle fibrecross-sections using a graphic tablet combined with a specially developed illuminated cursor for tracing directly on the microscopic image via a drawing tube. This approach permits relatively rapid, semi-automated measurement of the cross-sectional area with a high degree of accuracy and reproducibility. ATPase-stained cryostat sections from biopsy specimens of the human quadriceps femoris muscle were analyzed morphometrically with this technique. Measurements were made in 50 biopsies classified according to histopathologic findings into the following diagnostic groups: polymyositis (10 cases), myopathy (14 cases), neurogenic muscular atrophy (13 cases), and no significant histopathologic changes (13 cases). Histograms were constructed from the cross-sectional area distribution of the ATPase-positive type II fibres and the ATPase-negative type I fibres. The results show that, for the mean cross-sectional area, the majority of subjects in the normal group have coefficients of variation lying below 35% for both histochemical fibre types. In the three muscle disease groups, the coefficients of variation exceed 35% in the majority of cases, and show higher values for type II than type I fibres. In the polymyositis and the neurogenic muscular atrophy groups, the ratio between the mean area of the type I and type II fibers was on average lower than 1, whereas for the myopathy group this ratio was higher than 1. In general, the results confirm those of other investigators with respect to the particular susceptibility of the type II fibres to pathologic influences. Additions to the software make it possible to increase the number of visual diagnostic criteria that can be quantitated on the basis of the digitized fibre contours.

Two New Species of Acanthobothrium Van Beneden 1849 (Cestoidea: Tetraphyllidea) from Freshwater Stingrays in South America

Two new species of Acanthobothrium are reported from freshwater stingrays in northern South America. Acanthobothrium quinonesi sp. n. is described from Potamotrygon magdalenae Dumeril collected from the Magdalena River in northern Colombia and A. amazonensis sp. n. from P. circularis Garman collected in the Itacuai River of northwestern Brazil. Acanthobothrium quinonesi differs from A. amazonensis by having a smaller and anteriorly-curved cirrus sac, 43-60 rather than 50-72 testes, and bothridial hooks 100--142 ,urn long rather than 145-184 ,urn long. Characters used in the taxonomy of Acanthobothrium species are listed to show that the new species resemble each other and A. terezae, also from a South American freshwater stingray, more than they do any other members of the genus. Species of Acanthobothrium van Beneden 1849 parasitize a variety of marine and estuarine elasmobranchs (Goldstein, 1967; Williams, 1969) . Collections from the freshwater stingrays Potamotrygon magdalenae Dumeril in the Magdalena River of Colombia and from P. circularis Garman in th e Itacuai River of Brazil, contained specimens of two new species of Acanthobothrium which resemble each other more than they do any other known species. Worms were removed from host spiral valves, examined alive and fixed with warm AFA, or fixed in situ with 10% formalin; all were stored in 70 % ethanol. Study included examination of whole mounts stained with Mayer's hematoxylin and mounted in Canada balsam as well as study of serial cross sections cut at 8 p.m and stained with hematoxylin-eosin. Measurements are in urn unless otherwise stated with number of measurements (N) and mean values (x) indicated for certain characteristics. Figures were drawn with the aid of a drawing tube. Acanthobothr;um qu;nones; sp. n.

A method for measuring cyto-adherence of frozen tissue sections

A simple method for quantifying the cells adhering to frozen sections of mouse spleen using a microscope equipped with a drawing tube attachment, and a planimeter is described. It is a straightforward and reproducible technique which has been preliminary employed to study optimal binding conditions for E sheep and E oxAC.

Some Platyhelminth Parasites of Sirens (Amphibia: Sirenidae) from North America

A new genus and species of digenean and a new species of cestode are described and a previously described species of digenean reported for the first time from Siren intermedia from Illinois. A new genus is proposed for a previously described digenean, and another known species of digenean reported from Siren lacertina in Florida. Progorgodera foliata from S. intermedia has a foliate hindbody characteristic of members of Phyllodistomum and multiple testes arranged in 2 longitudinal rows characteristic of members of Gorgodera. Ophiotaenia sireni from the same host resembles 0. filaroides in number of testes, 0. amphiumae and 0. alternans in number of uterine branches, and 0. grandis and 0. marenzelleri in scolex size. Allassostomoides louisianaensis is reported for the first time from Siren intermedia. The new genus Cephalogonimoides is proposed for Cephalogonimus sireni from Siren lacertina, which differs from members of Cephalogonimus by having symmetrical testes, ceca extending to the posterior end of the body, an acetabulum twice as large as the oral sucker, and a muscular prepharynx; and by lacking a seminal receptacle. Telorchis stunkardi is reported from S. lacertina for the first time. The amphibian genus Siren L. is represented in North America by two species, Siren lacertina L. and S. intermedia LeConte. Five species of adult platyhelminths have been reported from S. lacertina: Cercorchis (= Telorchis) sireni Zeliff 1937, Stomatrema guberleti Byrd 1937, Gorgodera minima Cort 1911, Cephalogonimus sireni Premvati 1969, and Ophiotaenia sp. (Zeliff, 1937; Walton, 1958; Premvati, 1969; Loftin, 1960). Manter (1938) reported Cephalogonimus amphiumae Chandler 1923 from Siren sp. To date, no adult platyhelminths have been reported from Siren intermedia. From 1970 to 1975 adult platyhelminths were collected from Siren intermedia captured in southern Illinois. All specimens were fixed with AFA. Cestodes were first relaxed in cold tap water; digeneans were flattened with slight coverslip pressure. Worms were stained with Mayer's hematoxylin and mounted in Canada balsam. Measurements are in micrometers unless otherwise stated; figures were drawn with the aid of a drawing tube.

Five Species of Platyhelminths from Bufo marinus L. (Anura: Bufonidae) in Colombia with Descriptions of Creptotrema lynchi sp. n. (Digenea: Allocreadiidae) and Glypthelmins robustus sp. n. (Digenea: Macroderoididae)

Gorgoderina diaster, Cylindrotaenia am ericana , and Ophiotaenia bona rien sis are reported , and Crep totrema lunch! and Glypthelmins robustus described from Buio marinus from 3 locali ties in th e Republic of Colomb ia. All are new locality records and B. marillll s is a new host for G. diaster and C. am ericana. Creptot rema lijnchi differs from C. creptotte ma in possessing smaller eggs, rela tively smaller oral pap illae and suckers, and elong ate ra ther than spherical testes. Glypthe lm ins ro hustus differs from all other species in the gen us in possessing a pharynx which is significantly larger than th e acetabulum and tegumental spines restr icted to the an terior fif th of the body. If fur ther differs from G. facioi in possessing diagonal testes and slightly smaller eggs, and from G. palminedis in possessing an lshaped excretory vesicle and slightly smaller eggs. Th e known speci es of amphibian platyhelminths from Colombia have affinities with both North and Central as well as South America. Twenty-seven specimen s of Bufo marinus L . co llected from three localities in th e Rep ub lic of Colombia d uring Ju ne 1975 con ta ined sp ecim en s of fiv e species of ad u lt pl atyhel min th s, in cluding tw o previ ously undescribed . H ost specimens have been d eposite d in th e Unive rsity of Kansas M useum. Worms we re removed from the ho st and exam ine d live wi th the aid of a stereoscop e ; trematodes were flatten ed with negligible covers lip pressure, cesto des were relaxed in pond water; all were fixed w ith AFA, sto re d in 70% ethanol, sta ined wi th Mayer's hema toxylin , and m ounted in Canada b alsam. Measu rem ents are in micromete rs unless otherwise sta ted; figures were draw n w ith the aid of a drawing tube . Digenea Allocreadiidae Creptotrerna lynch; sp. n. (Figs. 1-3) Description (base d on 20 spec imens): Body oval to elonga te, 0.85 to 1.49 mm long by 0.39 to 0.67 mm wide; widest at mid body. Tegu ment thin, aspinous. Oral sucker subterminal, 156 to 276 long by 192 to 336 wide, with 2 small dorsolatera l papill ae. Prepharynx short; ph arynx 60 to 84 long by 120 wid e; ceca exten d near posterior end of body. Acetabulum ~ body length from anterior end, 264 to 396 long by 276 to 372 wide. Testes in posterior th ird of body, elongate, symmetrical Received for publication 23 September 1975 . * F unds for this study were provided th rough a gra nt from the National Geographic Society to Dr. Th omas B. Th orson, Un iversity of NebraskaLincoln. 429 to slightly oblique; left testis 300 to 480 long by H)2 to 252 wid e, right testis 32.5 to 540 long by 180 to 265 wid e. Cirru s sac dorsolateral to ace tabulum, 444 to 660 long by 84 to 108 wide; bipartite seminal vesicle, pars prostatica , and eversible cirrus pr esent; cirrus 1.50 by 42, unarmed. Gen ital pore median, anterovcntra l to cecal bifurcation . Short metrat erm present ( not apparent in holotyp e }, uterus short , loop ing between testes and acetab ulum; loops may extend extra ceca lly, Ovary posterolateral to ace tabulum, posterior to cirrus sac, 204 to 264 long by 216 to 288 wide. Vitellaria follicular, extracccal, follicles large, from level of ph arynx to posterior end of body; few interceca l follicles may be present. Vite lline recept acle median, posterodorsal to ootype; semin al receptacle present ; Mehl is' gland pr esent , Laurer's canal not obse rved . Slightly collapsed mature uterine eggs 5.5 to 67 long by ,35 to 38 wide. Excretory pore terminal; vesicle lshaped , may extend to anterior margin of testes. Host : Bufo marillus L. Site: At base of villi in middle porti on of small intestin e. Locality : 1 km north of San Cristobal Atlanti co Colombia . Holotype : USNM Helm. Coli. No. 73484. Para itjpes: USNM Helm. ColI. No. 73485; Univ. Neb, State Mus., H. W. Manter Lab . No. 2025 1.

A New Cestode, Imparmargo baileyi (Dilepididae: Dipylidiinae), from the Eastern Wild Turkey

Imparmargo baileyi gen. et sp. n. from the wild turkey, Meleagris gallopavo silvestris Vieillot, in West Virginia is characterized by regularly alternating genital pores, proglottid margins longer on the poral side, genital ducts passing between the osmoregulatory canals, singly encapsulated eggs, and small size. Ten species of cestodes in six genera have been reported from wild turkeys in the United States (Prestwood et al., 1973). During studies on the parasite fauna of eastern wild turkeys from two climax vegetative types in east-central West Virginia, an undescribed cestode was discovered. The cestode represents a new genus and species of the family Dilepididae. Specimens were relaxed and killed by chilling and preserved in a solution of 5% formalin and 2.5% acetic acid. Suitable specimens were stained with Reynolds' stain or Delafield's hematoxylin and prepared as whole mounts. Some tapeworms were serially sectioned at 6 / and stained with Delafield's hematoxylin and eosin. All drawings were made with the aid of a Wild drawing tube. Measurements, based on 25 adult specimens, are in microns unless otherwise stated; averages are followed by ranges within parentheses. The generic name, Imparmargo, is proposed to indicate the unequal margins of the proglottids. The species name, baileyi, is in honor of Mr. R. Wayne Bailey, whose efforts as a wildlife biologist are largely responsible for the restoration of the wild turkey in West Virginia. Imparmargo gen. n. Diagnosis Dilepididae, Dipylidiinae. Small cestodes with few proglottids. Rostellum tapering posteriorly, retractile, armed with regularly alternating circle of large hooks. Suckers unarmed. Craspedote proglottids wider than long except for the terminal gravid proglottid which is longer than wide. Immature and mature proglottids longer on poral Received for publication 27 June 1974. * This study was supported by the Federal Aid in Wildlife Restoration Act (50 Stat. 917), Contract No. 14-16-0008-676, Bureau of Sport Fisheries and Wildlife, U. S. Department of the Interior; and by Grant No. T01-AI-00325, NIH, Public Health Service. side. Osmoregulatory canals undulating throughout length of strobila. Genital openings alternating regularly. Genital ducts passing between osmoregulatory canals. Testes not numerous. Vas deferens strongly convoluted in anterior portion of poral side of proglottid. Cirrus pouch large, extending beyond osmoregulatory canals. Cirrus unarmed. Ovary large, bilobed, in center of proglottid. Vitelline gland irregularly rounded, slightly poral, increasing in size in maturing proglottids. Seminal receptacle large, muscular, posterior to coils of vas deferens. Vagina posterior to cirrus pouch. Uterus breaks down into egg capsules each containing a single egg. Imparmargo baileyi sp. n. (Figs. 1-6) Description Small cestodes, 2.531 mm (1.275 to 3.400) long by 1.012 mm (0.725 to 1.325) wide. Strobila contains 5 (4 to 7) immature, 6 (3 to 9) mature, and 1 (0 or 1) gravid proglottids with a total of 12 (9 to 15) proglottids. Rostellum 107 (80 to 135) wide by 240 (180 to 290) long, markedly longer when everted. Rostellum armed with single row of 24 (22 to 26) hooks which alternate regularly. Adjacent hooks offset by 2 A. Hook length 49 (45 to 57). Suckers ellipsoidal, unarmed, 202 (160 to 280) long by 162 (125 to 230) wide. Craspedote proglottids 3 to 5 times as wide as long except for terminal gravid proglottid which is longer than wide. Aporal side of immature and mature proglottids one-half to three-fourths length of poral side. Osmoregulatory canals much closer to median line at junctions of proglottids. Genital openings alternate regularly. Male and female genital ducts pass between dorsal and ventral osmoregulatory canals. Testes not numerous, more frequently 16 or 18 (14 to 21) in number, 58 (39 to 84) in diameter, posterior and posterolateral to ovary. Testes most numerous on aporal side. Vas deferens strongly convoluted, overlapping seminal receptacle and cirrus sac. Cirrus pouch large, 125 (90 to 149) long by 36 (27 to 48) wide, crossing osmoregulatory canals. Cirrus with a small tuft of "hairs" projecting from the area around the genital pore. Ovary slightly poral with indistinct margins, occupying a large portion of mature proglottids. Vitelline gland overlapping ovary, 117

Lateral superior olivary nucleus: a comparative analysis

The lateral superior olivary nucleus in 37 species of mammals was drawn with a Zeiss drawing tube from protargol-silver stained material. The pattern of laminar infolding generally conformed to the S-shaped and U-shaped convolutional patterns described by Hoffman (1908). In species with a relatively large cell number and a relative small cross-sectional area, there tends to be substantial laminar infolding within the convolutional pattern. Two independent estimates of the amount of laminar infolding were made and contrasted with the number of segments in the general convolutional pattern. Neither amount of laminar infolding nor number of convolutional segments was found to correlate with number of cochlear turns. However, in species in which the laminar pattern is well defined, the convolutional pattern and amount of laminar infolding appear to conform well to the sensitivity range and area of greatest sensitivity as seen in behavioral audiograms for the species.

Records of Cestodes from Chilean Sharks

Thirteen species of cestodes, including a new species of Prochristianella, are recorded from 6 of 11 species of Chilean sharks. Most of the cestodes were found in the same or closely related hosts as those previously reported from other localities. Several new host records are presented. Knowledge of cestodes from Chilean sharks is limited to only two references, Yafiez (1950) and Carvajal (1971), both concerning trypanorhynchans. In this report 13 species from Chilean sharks are recorded. Among these, Prochristianella musteli is new, whereas the remaining species have been reported in the literature from the same or closely related hosts. The sharks examined were collected from 1967-72, either by trawl nets of commercial fishing boats, operating from Papudo to Talcahuano, Chile, or from fishermen at San Antonio, Coquimbo, Antofagasta, and Archipielago de los Chonos. MATERIALS AND METHODS Whenever possible, the specimens were examined alive in seawater and relaxed in 10% magnesium chloride solution; they were then fixed and stained by methods already described (Carvajal and Goldstein, 1969, 1971). Drawings were made with the aid of a Leitz drawing tube. The tetraphyllideans from Mustelus mento were examined by Dr. Louis Euzet at the University of Montpellier, who corroborated my identifications. Measurements of the new species are in microns, unless otherwise indicated.

Der juxtaglomeruläre Apparat der Nieren bei Diabetes insipidus

Introduction: Several investigations of the pathophysiology of the renin-angiotensin-aldosterone-system in diabetes insipidus (DI) have recently appeared in the literature. Elevated plasma renin activity had been found in decompensated as well as in compensated DI. In our study, a correlation between the pathophysiologic findings and the extent of enlargement of the juxtaglomerular apparatus (JGA) was investigated. Material and Methods: 8 cases of clinically proven DI were examined. In all cases a neurogenic DI (tumors of the mesencephalon or the hypothalamus in 7 cases, and a purulent basal leptomeniningitis in one case) was present. The examination of the kidneys was done on H & E-stained frozen sections, 14–20 μ thick, fixed in 4% formalin. To determine normal values we chose 25 cases from our current autopsy material in which an activation of the renin-angiotensin-aldosterone-system could be eliminated on the grounds of clinical data and autopsy findings. A cytologic evaluation of the JGA by one of the conventional methods was impossible on our frozen sections. Therefore, we decided to measure the cut surfaces of the JGA in the histologic sections. For this purpose we used a drawing tube at × 1500 magnification. The microscope image was projected onto paper and the JGA were drawn by tracing the pictures with a pencil. The surface area of the drawn JGA was then measured with a planimeter. By shifting the slides under the microscope 50 JGA were measured at random and the total surface area was ascertained. Results: In the 25 control cases the normal range of the cut surface areas of 50 JGA was determined (Tab. 1). The results of our measurements in 8 cases of clinically proven DI show a clear enlargement of the JGA in 6 cases (Tab. 2 and fig. 2). The values in the 2 remaining cases lie in the high-normal range. Discussion: The present study shows that in most cases of DI the JGA is enlarged. Using the clinical data, we attempted to find relationships between the extent of JGA enlargement and clinical parameters, such as the duration of the DI state, extent of fluid deficit, and electrolyte disturbances. It was found that the extent and duration of decompensation of the water and electrolyte balance correlated best with the degree of JGA enlargement. This enlargement appears to be very dynamic. In case 5 the enlargement had developed in 4 days. In case 1 the size of the JGA was high-normal three months after neurosurgical correction of DI.

Use of the Camera Lucida to Directly Label Photomicrograph Negatives

ABSTRACT By using a camera lucida (drawing tube) positioned below the photo tube, many transmitting or reflected light microscopes may be set up so that all film log information is recorded on the film, eliminating much record-keeping.

Cathetocephalus thatcheri gen. et sp. n. (Tetraphyllidea: Cathetocephalidae fam. n.) from the Bull Shark: A Species Demonstrating Multistrobilization

Cathetocephalus thatcheri gen. et sp. n. is described from the spiral valve of the bull shark, Carcharhinus leucas (Valenciennes), taken in the Gulf of Mexico and the Atlantic coast of Florida. A new family is erected for the new genus. The species most closely resembles Pillersium owenium Southwell, 1927, in that both possess a scolex which is perpendicular to the long axis of the strobila. It differs, however, in having a single neck and holdfast organ rather than a bifurcate neck with 2 bothridia. Also, the surfaces of the scolex differ from those of P. owenium by possessing fleshy pa- pilliform structures on the leading and trailing edges rather than leaflike folds. Specimens with sev- eral strobilae are figured and discussed. A heavy infection of cestodes was found in the spiral valve of two specimens of the bull shark, Carcharhinus leucas (Valenciennes), that had been collected in Galveston Bay, Texas. The sharks had been flown to Sea World, San Diego, California, and died several days later. Additional specimens were also recovered from the same species of host at Mi- ami, Florida. The presence in those worms of a unique multistrobilate condition in some specimens prompted this study. The species does not have the typical tetraphyllidean scolex, but is considered here as representing a new genus in a new family in the order Tetraphyllidea. Worms were fixed in AFA, Bouin's fluid, or 10% formalin. Whole mounts were stained with cellestine blue B or Semichon's carmine. Sections of other specimens were cut at 6, 8, and 10 Au and stained with hematoxylin-eosin or Mallory's trichrome stain. All material was dehydrated in ethanol, cleared in xylene, and mounted in Piccolyte. Drawings were made with the aid of a drawing tube and stereo- scopic microscope. Average measurements are given, with ranges in parentheses. They are in millimeters unless otherwise indicated.

Journal article

A critical issue in quantitative neuromorphology is the accuracy and subsequent reliability of the tracing techniques employed to characterize neuronal components. Historically, the camera lucida was the only option for such investigations. In 1987, MBF Bioscience, Inc. (Williston, VT) developed the integrative Neurolucida computer-microscope system, replacing the camera lucida drawing tube with a Lucivid cathode ray tube, thereby allowing computer overlays directly on the view through microscope oculars. Subsequent advances in digital cameras have allowed the Lucivid system to be replaced so that microscope images can be traced by viewing the digital image on a computer monitor. Indeed, the camera systems now outsell Lucivid systems 9 to 1 (J. Glaser, personal communication, 08/2008). Nevertheless, researchers seldom note which of these configurations are being used (which may confound the accuracy of data sharing), and there have been no published comparisons of the Lucivid and camera configurations. The present study thus assesses the relative accuracy of these two hardware configurations by examining reconstructions of human pyramidal neurons. We report significant differences with respect to dendritic spines, with the camera estimates of spine counts being greater than those obtained with the Lucivid system. Potential underlying reasons (e.g., magnification, illumination, and resolution, as well as observer ergonomic differences between the two systems) for these quantitative findings are explored here, along with qualitative observations on the relative strengths of each configuration.

Two New Species of Cestoda from California Rays

Acanthobothrium olseni sp. n. (Tetraphyllidea: Oncobothriidae), characterized by number of testes and segments, size of hooks, cirrus sac, and ovary, was found in two of four shovelnose guitarfish from Newport Beach, California. Discobothrium myliobatidis sp. n. (Lecanicephalidae) is characterized by number of testes, length and shape of strobila, and distribution of vitellaria. It was found in one of three bat stingrays from Long Beach, California. The genus Discobothrium is discussed. From November 1966 through May 1968 150 elasmobranchs, representing five families of rays and 11 families of sharks, were examined for helminth parasites. This report is the first in a series on the findings of this survey. Specimens were removed from the spiral valve of the hosts, fixed in AFA, stained in Semichon's carmine, dehydrated in ethanol, cleared in xylene, and mounted in Piccolyte. Drawings were made with the aid of a drawing tube. All measurements are in microns unless otherwise stated. Average measurements are given with ranges in parentheses. Acanthobothrium olseni sp. n. (Figs. 1-4) The following description is based on 16 specimens found in the spiral valves of two shovelnose guitarfish, Rhinobatos productus Ayres, 1854 from Newport Beach, California. The species is named in honor of Dr. 0. Wilford Olsen.

Hydroxysteroid dehydrogenase activity in human skin. I. Histochemical techniques for the demonstration of 3-beta-hydroxysteroid dehydrogenase, and a method for the semiquantitation of its activity.

SUMMARY. A method has been established to estimate semiquantitatively the activity of HSD enzymes and is described in detail. In the main, the method depends on demonstrating NAD-dependent hydroxysteroid dehydrogenase by using nitro-BT as a hydrogen acceptor leading to the deposition of blue diformazan particles. The latter are then counted in a sebaceous gland by means of a Wild M20 microscope with a drawing tube attachment. The method is limited in use as a semi-quantitative comparison of enzyme activity in a few adjacent sections of a sebaceous gland.

Drepanidotaenia watsoni sp. n. (Cestoda, Hymenolepididae) from the Wild Turkey of Arkansas

Drepanidotaenia watsoni, a new hymenolepidid tapeworm from the small intestine of the wild turkey (Meleagris gallopavo), is described and compared with all known members of the genus. A key is presented to differentiate the 14 described species of the genus Drepanidotaenia. Distinguishing characteristics of D. watsoni are a flared region in the anterior end of the strobila, ten rostellar hooks, and the presence of hairlike projections on the outer embryonic membrane of mature oncospheres. Data are presented concerning the incidence and distribution of this cestode among wild turkeys of Arkansas. The reported cestodes of turkeys in the United States comprise 13 known species in six genera. Although the majority of these tapeworms infect both domestic and wild turkeys (Meleagris gallopavo), a few have been recorded from only the wild host (Reid, 1962). Little study has been given to helminths infecting wild turkeys, and it was not until 1963 that Maxfield et al. reported on the incidence and distribution of gastrointestinal helminths among wild turkeys of the southeastern United States. In that survey 32% of 31 turkeys were found infected with a hymenolepidid tapeworm which was limited in distribution to four counties in Arkansas (Arkansas, Dallas, Grant, and Lee counties). These collections were made during the spring gobbler hunts in April 1961. The cestode did not conform morphologically to known genera of the family Hymenolepididae previously found in turkeys. Additional viscera from 43 wild turkeys were obtained during the first half of the annual hunt (1-4 April 1963). These included 17 wild turkeys from Arkansas County, 19 from Grant County, four from Hot Springs County, and three from Lee County. Viscera were preserved in toto in a solution of alcohol and glycerine as described in Maxfield et al. Received for publication 25 January 1965. * This study was sponsored by the Southeastern Cooperative Wildlife Disease Study, School of Veterinary Medicine, University of Georgia through funds made available by the Eightyeighth Congress of the United States and administered through the Bureau of Sport Fisheries and Wildlife of the Department of the Interior through Contract No. 14-16-0008-676. Additional funds were provided by Grant No. G12,999 from the NSF. t Journal Series Paper No. 410, College Experiment Station, University of Georgia, Athens. (1963). Since tapeworms obtained by this method were unsuitable for detailed microscopic studies, four freshly killed birds were obtained from Grant County during the second half of the annual hunt (17-18 April 1963). Approximately 60 specimens with scolices intact were collected and fixed in steaming 10% formalin. Upon return to the laboratory, only four of the fragile scolices could be recovered, the others having disintegrated in transit. D scription of the adult tapeworm was based upon four scolices and 15 hematoxylinstained whole mounts. With exception of scolices, a minimum of 25 measurements was made of each structure. Drawings were facilitated with a Wild drawing tube and measurements were made with a calibrated ocular