344 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 



tending to be arranged in a straight, linear row on each side. Posterior 

 limit of vitellaria always (in 54 specimens) more than ys body length 

 from the anterior end and often at midbody level or beyond. Mehlis' 

 gland between testes. Uterus not extending anterior to ovary but does ex- 

 tend posterior to genital pore. Eggs light yellow, fairly thin shelled, 24 to 

 27 by 12 to 17 fi, usually about 25 by 17 /x. 



Testes large, subspherical, chiefly postovarian, diagonal, and not far 

 apart, sometimes almost tandem. Cirrus sac large, typical for genus, usu- 

 ally overlapping posterior testis but not reaching to this testis in 20 of 54 

 specimens. Genital pore some little distance anterior to posterior end of 

 body. Excretory pore terminal; excretory vesicle extending to anterior 

 testis. 



Measurements of the type specimen are: Length 1.350; width 0.352; 

 rhynchus diameter 0.215; mouth to anterior end 0.615; pharynx 0.060; 

 cirrus sac 0.427 by 0.113; eggs 24 to 27 by 12 to 14 [x. 



The name, pacificuSj is for the locality. 



Comparisons. P. pacificus differs in its large rhynchus from such spe- 

 cies as P. squamatus, P. grandis, P. aculeatus, P. ozakii, and P. viagnio- 

 vatus. It differs from P. crucibulus in separated rows of vitellaria, more 

 anterior mouth, more narrow eggs, and more tandem testes. It differs 

 from P. scalpellus, P. faciliSj and P. apertus in that the uterus does not 

 extend anterior to the ovary. An undescribed species of Prosorhynchus 

 from several species of Mycteroperca at Tortugas, Florida, is very similar 

 to P. pacificus, the only important difference being in size and color of the 

 eggs. It is interesting to note that of 3 species of Prosorhynchus from 

 Mycteroperca studied by the writer, this species is much more similar to 

 Atlantic collections than to its neighbor, P. gonoderus, from the Pacific. 



PROSOSTOMATA Odhner, 1905 



Gyliauchenidae Ozaki, 1933 

 Megasoleninae Manter, 1935 



The new genus described below is related to Apocreadium Manter, 

 1937 and is another allocreadid-like distome with lymphatic vessels. Oza- 

 ki (1934) reported the first distome, Petalocotyle nipponica, with a lym- 

 phatic system. At that time, Ozaki considered Petalocotyle in the family 

 Allocreadiidae. Manter (1935) discovered that Megasolena Linton and 

 Hapladena Linton both have well-developed lymphatic vessels and her- 



