DIGENETIC TREMATODES — MANTER AND VAN CLEAVE 319 



distance 0.380 to 1.219 mm. or about one-third to one-fourth body- 

 length and about twice length of forebody. Prepharynx short; 

 pharynx 0.051 to 0.095 mm. long by 0.051 to 0.102 mm. wide; 

 esophagus 0.119 to 0.153 mm. long or about II/2 times length of 

 pharynx ; intestinal bifurcation near anterior edge of acetabulum ; 

 ceca uniting and opening through a ventral anus (a, fig. 3) slightly 

 anterior to posterior end of body. 



Genital pore slightly to the left, opposite anterior half of esopha- 

 gus, varying from near base of pharynx to about midesophageal 

 level. Testes rounded to elongate, smooth, tandem, almost always 

 separated by vitellaria (only one apparent exception) ; anterior 

 testis about at midbody level. Cirrus sac (cs, fig. 5) elongate 

 pyriform, 0.102 to 0.110 mm. long in medium-sized specimens, 

 mostly anterior to intestinal bifurcation, containing a short cirrus 

 (cir), a tubular prostatic vesicle, and a few inconspicuous gland 

 cells (fig. 5) surrounding male tube immediately outside cirrus 

 sac; seminal vesicle (sv) external, tubular, sinuous, extending a 

 short distance posterior to acetabulum. Ovary indistinctly 3-lobed ; 

 seminal receptacle lacking; uterus preovarian; eggs 49 to 59 by 

 25 to 38^; uncollapsed eggs near ovary 49 to 59^ by 32 to 38/*; 

 collapsed eggs 51 to 56/a by 25 to 32/*. Anterior extent of vitelline 

 follicles varying from base of cirrus sac to posterior edge of acetab- 

 ulum; follicles almost always interrupted opposite one or both 

 testes and usually opposite ovary, almost always confluent between 

 testes and usually between ovary and anterior testis, filling post- 

 testicular space. The vitelline follicles are unusually variable in 

 this species. Excretory pore terminal ; excretory vesicle extending 

 to near ovary. 



Hosts. — Clinocottus analis australis Hubbs, tide-pool woolly 

 sculpin; Girella nigricans (Ayres), the common opaleye. 



Location. — Intestine. 



Tijpes. —Holotyve and paratye, U.S.N.M. Helm. Coll. No. 37143. 



Discussion. — The following 12 species of Opecoelus have been 

 named: elongatus Ozaki, 1925; gonistii Yamaguti, 1938; inimici 

 Yamaguti, 1934; lobatus Ozaki, 1925; mexicanus Manter, 1940; 

 minor Yamaguti, l^M', mutu Yamaguti, 1940; ozakii (Layman, 

 1930) Yamaguti, 1938; quadratus Ozaki, 1928; sebastodis Yama- 

 guti, 1934; sphaericus Ozaki, 1925 (type species) ; xenistii Manter, 

 1940. 



Of these species, three (sphaericus, minor, and sebastodis) are 

 extremely similar. Yamaguti himself (1934) confused O. minor 

 and 0. sebastodis, finally deciding (1940) that the latter differed 

 from the former only in shorter acetabular papillae and larger 



