DIGENETIC TREMATODES — MANTER AND VAN CLEAVE 331 



lobes all close together; slightly to right of midline; not far pos- 

 terior to acetabulum. Mehlis' gland anterior to ovary, between 

 ovary and seminal vesicle ; seminal receptacle lacking ; uterus short, 

 preovarian; eggs few, rather thin shelled, variable in size (owing 

 to abnormal shapes) , normal eggs 59 to 67/x by 40 to 45,.. Genital 

 pore (gp) median, immediately preacetabular. Vitelline follicles 

 (v) close together, extending from slightly posterior to acetabulum 

 to posterior end of body, covering most of the ceca; confluent pos- 

 terior to testes. Excretory pore terminal; excretory vesicle I- 

 shaped extending to posterior end of ovary where it flares out 

 laterally to receive the collecting tubes. 



Host.—Cynoscion nobilis (Ayres), white sea bass. 

 Location. — Intestine. 



Types.— Rolotyve and paratype, U.S.N.M. Helm. Coll. No. 37148. 

 Discussion.— The genus PleorcJiis contains three other species : 

 P polyorchis (Stossich, 1892) Railliet, 1896; americanus Luhe, 

 1906; and sciaenae Yamaguti, 1938. Manter (1949) has indicated 

 that P. mollis (Leidy, 1856) Stiles, 1896, almost certainly does not 

 belong in the genus. Pleorchis oligorchis Johnston, 1914, was 

 transferred to the genus Sc/iisiorcMs by Yamaguti (1942). P. cali- 

 forniensis differs from all three species in possessing many more 

 testes (almost twice as many as occur in any of the other species) . 

 It has a much shorter esophagus than does P. americanus. The 

 vitellaria do not reach to the acetabulum as they do in the other 

 three species. The ovary is more deeply lobed than in P. sciaenae. 

 The family Pleorchidae was named by Poche (1926) to include 

 Pleorchis Railliet and Schistorchis Luhe, 1906. Cable and Hun- 

 ninen (1942) pointed out that these two genera seemed unrelated 

 and that Pleorchis should be considered in the family Acantho- 

 colpidae. Schistorchis, with its unspined body and presence of a 

 seminal receptacle, seems more closely related to Decemtestis 

 Yamaguti, 1934. Since Pleorchis is the type genus of the Pleor- 

 chidae, its transfer to the family Acanthocolpidae forces the fam- 

 ily Pleorchidae to become a synonym of Acanthcolpidae. Pleorchis, 

 at least superficially, suggests the subfamily Campulinae (family 

 Fasciolidae). Similarities include such characters as large size, 

 body spines, H-shaped ceca, lack of seminal receptacle, l-shaped 

 excretory vesicle, preovarian uterus, and extensive vitellaria. The 

 testes are entirely different and the Campulinae are parasites of 

 marine mammals. Probably an important difference is the pres- 

 ence of very definite eyespots on Pleorchis, the cercariae of which 

 must therefore be oculate. Eyespots are lacking in all the known 

 life cycles of Fasciolidae. The H-shaped ceca may have developed 

 independently in Pleorchis and in Campulinae as well as in the 

 Accacoeliidae. 



