Oral Spines Research Articles

A New Species of Microporella (Bryozoa, Cheilostomata) from Alaska

Microporella speciosa sp. nov. is described from Alaska, USA. The new species is characterized by the following combination of features: 1) semicircular orifice with slightly curved and faintly denticu-late proximal edge having a straight, shallow groove, 2) two distal oral spines, 3) laterally directed avicularian rostrum with a broad, channeled tip, 4) open frontal pores, and 5) completely calcified basal walls. Opercula, avicularian mandibles, the ancestrula, and early ontogeny are also described.

Fenestrulina Asturiasensis sp. nov. (Bryozoa: Cheilostomida) from the Northern Coast of the Iberian Peninsula

A new species of Fenestrulina Jullien, 1888, F. asturiasensis sp. nov., is described from the northern coast of the Iberian Peninsula. The main diagnostic features of this species are: four to five oral spines, a completely porous frontal wall and non-stellate frontal pores. These features have allowed the author to differentiate it from F. malusii (Audouin), another species of the genus Fenestrulina Jullien recorded in the same region.

The Fine Structure of Saprodinium dentatum Lauterborn, 1908 as a Representative of the Odontostomatida (Ciliophora)

The fine structure of the sapropelic ciliate Saprodinium dentatum is described based on phase‐contrast microscopy, silver‐staining techniques, cryo‐fracture scanning electron microscopy, and thin sections. The study concentrates on a detailed analysis of the somatic cortex and the oral ciliature of this highly asymmetric, laterally compressed ciliate. The cell shape is dominated by a number of site‐specific spines and the curving course of 10 somatic kineties (SK 1–10). The SK, composed of dikinetids, show an intrakinety differentiation that seems characteristic for other odontostomes as well. The anterior segment of the SK is mostly ciliated, followed by a non‐ciliated segment in which the kinetosomes lack all typical fiber systems. Except for SK 4–6, the posterior segment is ciliated again, forming the spine kinetics associated with particular caudal spines. The anterior segment of SK 3 through SK 7 form the frontal band, which together with the two frontal kineties constitutes the main locomotory organelle for a ciliate that creeps on the substratum. A short kinety with inverse polarity, not seen in earlier light microscopical studies, was observed near the oral spine. We made particular effort to find a logical explanation for the observed association of the SK with the various caudal spines. The oral ciliature consists of nine adoral organelles located in a tripartite oral cavity. The absence of a paroral ciliature together with the position of the cytostome anterior to the adoral organelles may be the result of rotational movement of the oral apparatus during the evolution of these bizarre ciliates. Results are discussed with special reference to the phylogenetic relationship of the Odontostomatida to the Heterotrichida and no conclusive answer was found in this first electron microscopical study of an odontostomatid ciliate.

Timoniella absita n.sp. (Digenea: Cryptogonimidae) from the saltwater crocodile (Crocodylus porosus Schneider) from Australia

Timoniella absita n.sp. is described from the intestine of the saltwater crocodile (Crocodylus porosus Schneider) from the Northern Territory of Australia. Timoniella absita is closest to Timoniella unami and Timoniella loossi, but can be distinguished from them by the number of oral spines and the posterior extent and arrangement of vitelline follicles, and possibly by the ratio of oral sucker width to pharynx width and the form of the seminal receptacle. The new species is the first representative of Timoniella to be described from the Indo-Malaysian – Australian region.

Frontal ambulacral and peribuccal areas of the spatangoid echinoid Echinocardium cordatum (Echinodermata): a functional entity in feeding mechanism

Echinocardium cordatum (Pennant, 1777) were collected in Normandy, France, in March and November 1985. The grooved frontal ambulacrum of the burrowing echinoid E. cordatum functions in transferring surface sediment from the apex to the mouth of the echinoid. Particles that fall down the burrow's chimney accumulate between the spines of the apical tuft and are taken over by specialized groove spines. Due to the slope of the groove and the type of floor spines it harbours, four successive regions can be recognized, namely the adapical region, the fasciolar region, the ambital region, and the adoral region. As a general rule aboral floor spines (i.e. club-shaped, golf-club-shaped, and isodiametric spines) function in gathering particles while propelling them mouthwards; they simultaneously embed particles in a mucous string. The oral floor spines (i.e. spatulated spines) function in hauling and guiding the mucous string towards the peribuccal area of the echinoid. Once facing the peribuccal area, particles are picked up by the peribuccal tube feet that either transfer them into the esophagus or scrape them out against the peribuccal spines. Spine-retained particles are either sucked up by the pumping action of the esophagus or fall to the burrow's floor where the tube feet may pick them up again. Together the apical tuft, the frontal groove, and the peribuccal area form an efficient food-collecting system that transfers trapped surface particles from the echinoid apex down to the mouth. Compared to that of most other spatangoids the frontal ambulacrum of E. cordatum is highly specialized. Such specialization is related to colonization of fine sediment, as is the occurrence of a chimney linking the burrow to the sediment surface. Actually the burrow's chimney is the only route for oxygen and food supply; it acts as a real ecological umbilical cord for spatangoids buried in fine sediment.

Studies on the Metagonimus fluke in the Daecheong reservoir and the upper stream of Geum river, Korea

The prevalences of the fluke belonging to genus Metagonimus have been reported along the upper stream of inhabitants by several workers since 1980, however the taxonomical problems of the fluke was not yet settled. The larval flukes; cercaria and metacercaria as well as their intermediate hosts, and adult were studied in order to identify the Metagonimus in the areas. The results obtained are summarized as follows: The snails, Semisulcospira globus were collected from the three different localities along the upper stream of the River. The cercariae were found from 125(7.2%) out of 1,730 snails by natural emerging method, and were identified into 5 species including Metagonimus sp. (3.7%), Pseudexorchis major(1.4%), Cercaria nipponensis (0.9), Cercaria incerta (0.6%) and Cercaria yoshidae(0.6%). Cercariae of Metagonimus species had four to five oral spines on its anterior of the first line. The cercariae of Metagonimus were experimentally exposed to goldfish. Infection rate was 22.9% out of 105 goldfish, and the encysted metacercariae were found in fins(86.7%) and on scales (13.7%) of the fishes, but not in their muscle, head or visceral organs. Seven species of fish were caught in the Daecheong reservoir and the upper stream. Infestations with metacercaria of Metagonimus were found 100% in Opsariichtys bidens and the parasitized numbers of the metacercariae were observed from 250 to 2,400 per fish. In the upper stream, Zacco temmincki, Z. platypus and Pseudogobio esocinus were infected 100% with the metacercaria, on the other hand, the fishes caught in the reservoir showed the lower infestation rates, and a few metacercariae found in the fishes Carassius carassius and Cyprinus carpio in the reservoir and the stream. The majority of metacercariae was detected only on the scales of fishes. In order to know the infectivity and the distribution patterns in the intestine of hosts, rats and dogs were infected with the metacercariae obtained from O. bidens and Z. platypus. In addition the metacercariae obtained from Z. temmincki, P. esocinus and goldfish were given to the rats. The recovery rates of the worms in the small intestine of dogs were higher (63.3-65.8%) than those of the rats (3.5-31.6%). The flukes were found mostly in the middle and the lower part of small tntestine of the rats and the dogs, but no worm was collected in the upper part of the intestine of rats. The size of adult flukes varied by the hosts. In the adult flukes, oral sucker was smaller than ventral sucker, and the right and left testes were located diagonally, the uterine tubules circled around the upper left testis. The average egg size was 29.1 x 17.7 micro-meter. According to the above results, the flukes belonging to genus Metagonimus distributed along the Geum River was concluded to be identical with Miyata type of M. yokogawai as that Saito had proposed.

Experimental evaluations of substrate types as barriers to sea urchin (Strongylocentrotus spp.) movement

Descriptive evidence that sandy surfaces and rock ledges inhibit progress of grazing sea urchins prompted an experimental investigation of physical obstacles to urchin movement in a subtidal area of reef and kelp off southern California in 1980. In laboratory experiments, we found that both red (Strongylocentrotus franciscanus) and purple (S. purpuratus) urchins can negotiate sand using their oral spines, although purple urchins are slower and more hesitant to do so. In field experiments, we observed the fates of starved red urchins transported to replicate plots within stands of sand-or rock-based understory kelp (Pterygophora californica). Urchins in rock plots retreated to nearby crevices from where they ate attached kelp. After finding kelp blades, urchins soon disappeared from sand plots because individuals in small groups may have difficulty holding and eating attached kelps on unconsolidated surfaces. In another experiment, red and purple urchins reached kelp on a rock ledge by mounting an artificial ramp. We conclude that by using their tube feet, individuals of both species move best over flat, hard surfaces, although soft substrate may constitute a major barrier only to purple urchins. In the absence of effective predator control, urchins can surmount most sand or rock barriers when water motion subsides. Hence, their ability to coordinate spine movements to negotiate soft substrates may be an adaptation to invade kelp refuges during quiet periods if preferred drift food is unavailable.

Revision of the Acanthostominae Poche, 1926 (Digenea: Cryptogonimidae)*

The digenean subfamily Acanthostominae is redefined and revised. Those 36 species exhibiting (1) lateral, follicular vitellaria, (2) a prepharynx, (3) a spinose tegument, (4! tandem or obliquely tandem testes contiguous in the hindbody, (5) a preacetabular pit, (6) an acetabulum not associated with a ventrogenital pit, (7) ceca extending near the posterior end o(the body, (8) a spherical or subspherical ovary, located near to and anterior to the testes, (9) an immediately preacetabular genital pore, (10) a genital pore not located in the preacetabular pit, (11) cpitheliated esophagus and ceca, non-epitheliated prepharynx, (12) a Y- or V-shaped excretory vesicle with postacetabular bifurcation, and (13) a terminal oral sucker armed with a single row of spines all belong in the Acanthostominae. Acanthostomes and their relatives are considered members or the Cryptogonimidae. Neotropicotrema bychowskyi and Allomacroderoides lepisostei ate transferred to Perezitrema and, along with Perezitrema viguerasi, represent plagiorchiform rather than opisthorchiform digeneans. Available names serve to partition acanthostomes into six genera. Acanthostomum (s.s.) contains the species spiniceps, absconditum, knobus, niloticum, minimum, gnerii, astorquii, americanum, and megacetabulum. The speciespavida, caballeroi, marajoaru. and brauni comprise Caimanicoia. Gymnatrema contains two species, gymnarchi and pambanense. Eight species, coronarium, productum, vicinum, gonotyl, atae, elongatum, crocodili, and nicolli, comprise Proctocaecum. Alrophecaecum contains the species burminis, indicum, pakistanensis, slusarskii, proctophorum, asymmetricum, and sunhai. Lastly, Timoniella contains imbutiforme, praeterita, scyphocephala, loossi and unami, as well as a new species from Venezuela previously misidentified as Acanthostomum scyphocephalum. The new species has smaller oral spines and exhibits blindly-ending ceca rather than ceca opening to the exterior near the posterior end of the body like T. scyphocephala. Haplocaecum is a synonym oi Atrophecaecmn. Acanthostomum bagri is a synonym of A. absconditum, A. nuevoleonensis is a synonym of A. megacetabulum, A. acuti is a synonym of Caimanicoia marajoara, A. diploporum is a synonym of Proctocaecum coronarium, Atrophecaecum hindusthanensis and Acanthostomum (Alrophecaecum) alii are synonyms of Atrophecaecum burminis, and Timoniella atherinae is a synonym of T. praeterita. Acanthostomum spiniceps knobus is elevated to A. knobus based on shape and mean number of oral spines, and on body proportions. A replacement name, nicolli, is proposed for a species of Proctocaecum originally designated Acanthochasmus quaesitus, a nomen nudum. Paracanthostomum and Ateuchocephalus are most closely related to Atrophecaecum but their status is not completely resolved pending description of an undescribed species recently collected by another worker. Numerical phylogenetic analysis of all species based on 25 characters in addition to the 13 which characterize the subfamily as a whole suggests that each recognized genus constitutes a monophyletic lineage. Biogeographical and coevolutionary relationships predicted by the genealogical hypotheses indicate that acanthostomes originated as piscicolous parasites occurring throughout Gondwana prior to the Cretaceous and that adaptive radiation featured invasion of aquatic reptilian hosts, primarily crocodilians, in three major instances involving four acanthostome genera.

The structure and arrangement of echinoid tubercles

Tubercles and spines of 33 species of extant irregular echinoids were studied to provide data for interpreting tubercle structure and arrangement in fossil echinoids. Tubercle morphology is analysed functionally. It is possible to infer much about the posture, movement and function of the associated spine from tubercle morphology. The development and direction of areole enlargement and the structure of the platform are the most important features in this respect. Surface stereom porosity is used to differentiate tubercles and miliaries, which bear either spines or pedicellariae, from granules, which have no such appendages. Tubercles of regular echinoids are usually radially symmetrical and can be broadly separated into fixed-pivot and sliding-pivot systems. In irregular echinoids, spines are usually modified for a particular function and tubercle morphology is correspondingly varied. The power stroke of the oral spines is radial in pygasteroids and holectypoids, whereas, in clypeasteroids and cassiduloids, it is posterior. This is reflected in their different burial and locomotory behaviour. Oral spine and tubercle arrangement in Cassidulus resembles that found in spatangoids and this again is reflected in its behaviour. Spine and tubercle differentiation becomes quite pronounced in certain clypeasteroids. It is argued that lunules and notches are modifications which allow sand dollars to feed on the organic-rich surface layer of sediment while remaining infaunal. Tubercle and spine diversity is most pronounced in the spatangoids and is described in detail for Echinocardium. Each group of spines with a particular function is associated with morphologically distinct tubercles. Tufts of spines are readily recognizable from the tubercle arrangement. The considerable variation in the arrangement of spines and tubercles within the anterior ambulacrum is thought to reflect the varying emphasis placed on adoral transportation of sediment. Fasciole arrangement shows no correlation with depth of burial or grain size of the substratum. Aboral tubercle density is correlated with sediment grain size. To maintain a water-filled space between the tip of the spines and the test surface, echinoids increase spine density and develop a uniform covering of spines with either distally swollen or spatulate tips. In spatangoids, a more effective coverage is achieved by development of curved or oblique aboral spines, and the aboral mucous coat prevents fine particles from falling between spines and clogging the burrow. The structure and arrangement of tubercles can be extremely useful in palaeobiological studies.

Trematodes of Marine Fishes from South Australia. 6. Monostephanostomum manteri gen. et sp. n. (Acanthocolpidae)

Monostephanostomum manteri gen. et sp. n. (Acanthocolpidae) is described from Arripis georgianus from Port Willunga and A. trutta from Adelaide, South Australia. It is similar to Stephanostomum Looss, 1899, but it differs in having a single complete row of circumoral spines. The trematodes described below were received from the Australian Helminthological Collection (see Kruse, 1979), University of Adelaide, South Australia, as fixed specimens stored in glycerin alcohol. The glycerin was removed by placing the digenes in several changes of 70% EtOH over a period of time. Whole mounts were stained in Mayer's hematoxylin, dehydrated in EtOH, cleared in xylene, and mounted in Canada balsam. Drawings were made with the aid of a camera lucida; measurements are in micrometers with averages in parentheses. Monostephanostomum gen. n. Generic diagnosis: Acanthocolpidae; Stephanostominae. With the characters of Stephanostomum except for oral sucker with single row of a few, large, uninterrupted circumoral spines. Parasitic in intestine of marine fishes. Type and only species: M. manteri. Monostephanostomum manteri sp. n. (Figs. 1-4) Hosts and localities: Arripis georgianus (Cuvier and Valenciennes); Arripidae; Tommy Rough (type host); Pt. Willunga, 1934; Gulf St. Vincent, 1962; A. trutta Whitley; Australian Salmon; Adelaide, 1937. Location: Intestine. Types: Holotype--South Australian Mus. No. V1911. Paratype-Australian Helminth. Coll. No. S306; USNM Helminth. Coll. No. 75503; Univ. Nebraska State Mus., Manter Lab. No. 20980. Description (basedon5mature specimens): Body 1,691 to 2,470 (1,951) long by 248 to 456 (308) wide at midbody; tapering toward each end. Oral sucker terminal, 96 to 125 (104) long; circumoral spines 16 or 18, in uninterrupted row, 61 to 64 (62) long. Acetabulum 128 to 176 (152) long; '/3 to almost /2 body length from anterior end; sucker length ratio 1:1.33 to 1.6 (1.46). Conspicuous circular muscles in short, unspined postoral region; body spines 46 to 53 (50) long anteriorly, then decreasing in size, while increasing in number before disappearing at about midbody. Pigment granules in forebody. Prepharynx 330 to 422 (371) long; pharynx 96 to 144 (113) long by 42 to 86 (59) wide; esophagus 16 to 35 (26) long; ceca joining excretory vesicle posteriorly to form uroproct. Genital pore median, immediately preacetabular. Testes elongate, tandem, subequal, in posterior half of hindbody; anterior testis 21 to 26 (24) long by 10 to 13 (12) wide, posterior testis 28 to 34 (32) long by 11 to 14 (13) wide; posttesticular space 107 to 355 (216). Cirrus sac sinuous with swollen base near anterior end of ovary; 348 to 536 (464) long by 48 to 80 (59) greatest width; containing saccate seminal vesicle, pars prostatica with scanty prostatic cells, and long cirrus with knoblike protuberances. Genital atrium short. Ovary smooth, wider than long, immediately pretesticular; 181 to 402 (272). Seminal receptacle absent. Uterus preovarian, turning backward from acetabulum to join metraterm near ovary. Metraterm sinuous, as long as cirrus sac; unspined. Vitelline follicles large, circumcecal, uninterrupted, confluent anterior to acetabulum and in posttesticular space. Eggs 80 to 94 (86) by 35 to 48 (42). Cloacal pore terminal; excretory vesicle extending to ovary. The name Monostephanostomum refers to the single row of oral spines.

On the morphology and life-history ofStephanostomum caducum(Looss 1901) Manter 1934 (trematoda, acanthocolpidae)

Abstract The cercaria of Stephanostomum caducum (Looss 1901) Manter 1934, develops in redia in the marine prosobranch Natica alderi. The ocelate cercaria has two alternating rows of oral spines and a stylet. The distal part of the tail is able to invaginate and function as a sucker. The cercaria is probably identical with Cercaria obtusicaudata Pelseneer 1906. The cercariae encyst below the epidermis of the mouth of fish belonging to the family Gobiidae. The nietacercariae have 24 or 25 oral spines in each of the two rows. S. caducum developed in the pyloric caeca of cods fed on experimentally infected gobies. Cod, Gadus morhua, is the natural final host for S. caducum in Danish waters. The different developmental stages were studied using the scanning electron microscope.

A comparative study of the life style of two Jurassic irregular echinoids

The irregular echinoids Plesiechinus ornatus (Buckman) (Pygasteroida) and Galeropygus agariciformis (Forbes) (Cassiduloida) occur together in beds of the murchisonoe Zone, Bajocian, outcropping in the Cheltenham region of Gloucestershire. These species were largely restricted to different lithofacies within the carbonate shelf environment. Both adopted a hidden mode of life but achieved this by different techniques. Plesiechinus had fairly short spines and strongly muscular podia over the whole corona and was able to cover itself with coarse substrate particles. The oral tubercles are bilaterally symmetrical and are radially arranged. The oral spines are thought to have pulled sediment out from beneath the test, excavating a small depression for it. Galeropygus bore a dense covering of very small spines and its tube feet were differentiated into aboral respiratory podia and oral suckered podia. It had a preferred anterior direction of locomotion and is thought to have buried itself completely by excavating and ploughing into the substrate as it moved forward. Plesiechinus fed using only its lantern and postulated peristomial tube feet, whereas Galeropygus was a continugus sediment swallower and used its phyllode tube feet and peristomal lip spines in transferring particles towards the mouth.

The feeding activity ofEchinostrephus molaris(de Blainville) in the central red sea

Echinostrephus molaris (de Blainville) is a small Indo‐pacific echinoid which burrows in coral reef limestone. Normally individuals do not leave the burrows so they cannot graze on algae growing around the burrow mouth. E. molaris catches floating algal particles with its long aboral spines. When a particle touches one of these organs or a tube‐foot in the area, the surrounding spines converge and grip it. Captured fragments are lowered to the test by further tube‐foot and spine action and are then passed across the ambitus towards the mouth. They are held by the oral tube‐feet and the shorter curved oral spines which aid ingestion. The behavioural and structural modifications shown for this habit are discussed. Burrowing and particle collecting have allowed E. molaris to occupy a particular niche on the reef. A similar method of food gathering is reported for Echinometra mathaei (de Blainville).

Glaucivermis spinosus gen. et sp. n. (Digenea: Zoogonidae) from the Southern Kingfish, Menticirrhus americanus (Linnaeus), in the Coastal Waters of Mississippi

Glaucivermis spinosus is described from the intestine and pyloric ceca of Menticirrhus americanus collected near Ocean Springs, Mississippi, in the Gulf of Mexico and adjacent waters. The genus is characterized primarily by having a preacetabular intestinal bifurcation, a preacetabular sinistral genital pore, a bilobed vitellarium, a swelling of Laurer's canal to form the seminal receptacle, and tandem to diagonal testes. It is most similar to the genus Diphtherostomum from which it differs primarily in the arrangement of the testes. Specimens of a new species of zoogonid trematode were collected during the spring and autumn of 1970 from Menticirrhus americanus in water of both high and low salinity near Ocean Springs, Mississippi. Because of the unique arrangement of the testes, a new genus is erected for the worm. Living trematodes were fixed in hot AFA solution and subsequently stained with Van Cleave's hematoxylin. All measurements are given in microns. Glaucivermis gen. n. Diagnosis: Body small, spinose; oral spines present. Oral sucker terminal. Prepharynx short. Bifurcation of esophagus preacetabular. Ceca terminating in or slightly posterior to acetabular zone. Acetabulum without prominent lip. Genital pore sinistral, preacetabular. Testes tandem to diagonal, usually completely in hindbody. Cirrus sac extending into acetabular level; containing large prostatic vesicle and bipartite seminal vesicle. Cirrus with minute papillae. Ovary between anterior and lateral to forward testis, seldom overlapping it. Seminal receptacle a swelling of Laurer's canal. Vitellarium bilobed, near posterior portion of ovary. Uterus filling most of hindbody. Metraterm well developed. Eggs containing miracidia without eyespots. Parasites of marine fishes. Type and only species: Glaucivermis spinosus sp. n. (Figs. 1-5) Description (based on 18 mature specimens): Body usually spindle-shaped, with forebody attenReceived for publication 8 December 1970. * This study was conducted in cooperation with the Department of Commerce, NOAA, National Marine Fisheries Service, under Public Law 88-309, Project No. 2-85-R. uated and posterior end of body usually more pointed than anterior; 412 to 795 long by 119 to 175 in maximum width (at acetabular level). Tegument completely spinose; spines of hindbody short and fine; spines of forebody robust and thornlike, somewhat smaller anteriorly and very short around oral sucker except most anterior row on dorsal side with 9 to 11 (10 on 16 specimens) large globular spines. Numerous small elongated gland cells opening externally, primarily in forebody. Oral sucker funnel-shaped, 51 to 79 long by 49 to 70 wide. Acetabulum weakly developed, 63 to 91 long by 61 to 81 wide. Sucker width ratio 1:1.0 to 1.4. Forebody 45 to 57% of body length. Prepharynx short when evident. Pharynx 28 to 37 long by 19 to 23 wide, with 4 inconspicuous anterior lobes. Esophagus 1.7 to 7.2 times length of pharynx. Testes smooth to somewhat irregular, usually contiguous but occasionally well separated; anterior testis 70 to 98 long by 37 to 81 wide, usually postacetabular, sometimes at acetabular level; posterior testis 67 to 112 long by 44 to 67 wide. Posttesticular space 6 to 17% of body length. Genital pore at or near margin of body. Cirrus sac arcuate, 112 to 216 long by 33 to 44 wide, or 3 to 5 times longer than wide, extending to anterior margin or middle of acetabulum; cirrus when retracted a little more than 1/3 length of sac. Ovary smooth, 58 to 88 long by 42 to 70 wide, usually somewhat dextral, overlapping posterior portion of acetabulum. Vitellarium deeply bilobed, either larger or smaller than ovary. Uterus with proximal end usually filled with sperm, distal end having muscular portion before joining metraterm. Metraterm (= terminal organ) conspicuous, muscular, with fine delicate papillae, 61 to 88 long by 21 to 44 wide, or about 2 to 4 times longer than wide, with conspicuous outpouching near distal end, joining to short genital atrium by short narrow muscular duct. Eggs 24 to 30 long by 12 to 16 wide in mounted specimens, 26 to 34 by 16 to 19 in living ones; egg shell prominent, operculated. Excretory vesicle saccular, epitheliated, usually

Some observations on the locomotion and feeding of the sand dollar, Dendraster excentricus (Eschscholtz)

Dendraster excentricus was observed at Alki Point, Seattle, Washington, at a maximum density of 629 animals/m 2 during the summer of 1967. The animal usually remains half buried subvertically with the anterior end downwards at high tide and buries itself completely during low tide. There is no uniform orientation in relation to the tidal current; the animals lie randomly. Young animals of less than 15 mm in diameter move mainly by their suckered tube-feet; they can climb an aquarium wall. In the adult, primary oral spines are the major locomotor organs. Forward movement (progression) is the dominant pattern of locomotion, although a reversed movement is possible. The animal can bury itself within 15 min and right itself within 2 h. Young animals can bury and right themselves much faster than the adults. Suspended matter, composed mostly of diatoms, is first swept to the test surface and then to the food tracts by ciliary currents. In the food tracts the particles are caught in the mucus which is secreted by the mucus glands in the floor of the tracts. These mucus strings are then carried by the ambulacral tube-feet into the peristome where they are finally collected into the mouth by the teeth with the help of buccal tube-feet and oral spines.

A REVISION OF THE SUBFAMILY HAPLORCHINAE LOOSS, 1899 (TREMATODA: HETEROPHYIDAE). I. THE HAPLORCHIS GROUP.

Earlier schemes of classification of the family Heterophyidae have been based in large part on such features as shape of body, presence of oral spines, number and position of testes, and distribution of vitellaria (Witenberg, 1929; Ciurea, 1933; Mueller & Van Cleave, 1932). Price (1940a) was the first to make extensive use of features of the ventrogenital complex (ventral sucker, gonotyl, genital pore, terminal male duct) and excretory bladder, and produced the first reasonable classification of both the family Heterophyidae and the superfamily Opisthorchioidea. In despite of the obvious significance of the rationale of Price's approach, later authors (Morozov, 1952, 1955; Yamaguti, 1958) have largely ignored the ventrogenital complex and recently discovered life-history data, and have used much the same sorts of features as earlier authors.

Variation in the Number of Oral Spines of Phagicola longicollis Kuntz and Chandler, 1956, and the Description of P. inglei n. sp. (Trematoda: Heterophyidae)

During the course of investigations on a species of Phagicola from Mugil cephalus L., the Striped Mullet, and M. curema Cuvier & Valenciennes, the White Mullet, we have had the opportunity to examine numerous specimens of Phagicola longicollis. Through the courtesy of Allen McIntosh, Parasitologist, Animal Disease and Parasite Research Branch, U. S. Department of Agriculture, the type slide, U. S. National Museum Helminthological Collection No. 38169, was obtained. This slide contains a number of specimens of P. longicollis (Fig. 1), two P. ascolonga (Witenberg, 1929) Price, 1932, and several Heterophyes heterophyes (Siebold, 1852) Stiles & Hassall, 1900. Phagicola longicollis can be readily separated from the 2 specimens of P. ascolonga by the fact that in the former the uterus never extends posteriorly beyond the testes while in the latter the uterus always extends beyond the testes. Other differences include shape of body, structure of gonotyl, and posterior extent of the oral appendage. We observed, on the type slide, some specimens (syntypes) of P. longicollis with 14, others with 15, and three with 16 oral spines in a single row. Some damaged specimens had less than 14 oral spines. The original description of this species by Kuntz and Chandler (1956) states: Mouth surrounded by single circle of 14, sometimes 15, spines, . The late Dr. A. C. Chandler, in a personal communication (1957), stated: ... I counted the oral spines on several dozen specimens of Phagicola longicollis and found 14 in most, 15 in some, and thought I counted 16 in a few, but decided I had made an error. However, it is quite possible that there is a variation from 14 to 16 in this species, so some of the specimens on which you found 16 spines may belong to this species.... Dr. Chandler kindly sent us most of his specimens of P. longicollis and P. ascolonga for examination. Included in this material were specimens of a species of Phagicola that were obviously not P. ascolonga. Except for 1 specimen (Fig. 3) having a coronet of 17 oral spines in a single row and others having 16 oral spines they conform with the original description of P. longicollis. We feel, therefore, from the observations stated above, the description of P. longicollis should be expanded to include a variation of from 14 to 17 oral spines. Stunkard and Uzmann (1955) discuss the Ascocotyle-Phagicola complex. They conclude, Decision on the taxonomic status of Phagicola should await more complete information, especially on the developmental stages of its members. Additional information may show that Phagicola is not a valid genus. However, it has

Two Flukes, Phagicola macrostomus n. sp. and Phagicola byrdi n. sp., from the Turkey Vulture (Trematoda: Heterophyidae)

Diagnosis. Small, spatulate worms about 0.5 mm long and half that broad. Body divided by a slight constriction at the level of the acetabulum. All but the posterior surface covered by semicircular cutaneous scales. Oral sucker diameter about one-fifth of body length, with no dorsal anterior prolongation. Acetabulum slightly more than one-half the diameter of oral sucker, center just anterior to middle of worm. Eighteen thick, blunt-pointed oral spines evenly spaced in a single row around oral opening, length about one-third of oral sucker diameter but somewhat variable. Oval diverticulum thick-walled, straight, overlapping pharynx for short distance. Prepharynx nearly as long as oral diverticulum. Pharynx muscular, twice as long as wide, divided by circular constriction. Esophagus shorter than pharynx. Ceca

Stamnosoma armatum <i>Tanabe</i>ノ發育史知見補遺

1) The author confirmed that the first intermediate host of Stamnosoma armatum is Thiara (Melania) libertina Gould on the following grounds:a) The author obtained characteristic metacercariae (encysted cercariae) which are morphologically identical with that of Stamnosoma armatum by infection-experiment to noninfected fishes (goldfish, Zacco platypus and Acheilognathus limbata) with a sort of cercariae which were found in the liver of Thiara libertina and belong to the “Cercaria B of fulvopunctata group (by Kobayashi's classification).”b) The author brought up characteristic adult worms which are morphologically identical with that of Stamnosoma armatum from the above mentioned metacercariae by feeding-experiment to noninfected dogs.2) The above mentioned cercaria is rich in yellowish-brown pigment in the body and has a pair of eye-spots. Its body measures 0.098 (0.084-0.119) mm in length and 0.056 (0.049-0.063) mm in breadth; its tail 0.111 (0.091-0.133) in length and 0.015 (0.014-0.018) mm in breadth on an average.3) Moreover proved the author experimentally the following facts:a) Opposite to the Nishigori's description a group of larger spines which are situated on the dorsal side of the mouth of this cercaria is not the anlage of the “head spine” of the metacercaria, but it seems highly probable that it is a sort of apparatus which functions mechanically to assist the penetration of the cercaria into the second intermediate hosts. The author termed those spines “oral spine” instead of “head spine”.b) This cercaria encysts and develops to a complete metacercaria not only in the gills but also rarely in the fins of certain fishes.