442 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 2 



The name mantae is for the generic name of the host. 



Comparisons. This species differs from P. vaginicola in possessing 

 accessory suckers in the oral sucker, in anterior extent of vasa efferentia, 

 in more anterior genital pore, in shape of the genital atrium, in posterior 

 extent of the testes, and, if Dollfus' identification of the ovary is correct, 

 in the shape of the ovary. 



Discussion. The genus Paronatrema was named by Dollfus in 1937 

 from two immature specimens from the oviduct of Squalus (?) sp. from 

 New Guinea. Dollfus named the genus and the species (P. vaginicola) 

 tentatively because of the scarcity and immaturity of the material. He 

 noted relationships to the genus Otiotrema. The writer agrees with such 

 indicated relationship and includes Paronatrema in the family Syncoe- 

 liidae. 



The location of the trematodes on the surface of the ray (a large se- 

 lachian approximately 14 feet in diameter) is unusual for a distome. The 

 sex of the host was not recorded, and the reproductive ducts were not 

 examined. It is quite possible that the specimens collected had migrated 

 from the oviducts. 



The peculiar accessoiy suckers arranged in a ring around the periph- 

 ery of the acetabulum were noted by Dollfus. In P. mantae their numbers 

 in 3 specimens are 29, 34, and 37, respectively. Each accessory sucker (fig. 

 131) is a subspherical body (muscular) with the free end cup shaped- 

 Each is attached at the angles formed by a scalloping of the muscular 

 border of the acetabulum. 



A similar ring of small accessory suckers occurs just within the mouth 

 cavity near the edge of the oral aperture. The anterior edge of the body 

 surmounting the oral sucker is irregularly scalloped or indented, but the 

 ring of suckers is internal just within the oral cavity. The number of these 

 suckers is 41, 45, and 47 in 3 specimens. As compared with the acetabular 

 suckers they are smaller, more numerous, and of different shape. They 

 are flat, cuplike, pedunculated structures (fig. 130). They were not 

 described for P. vaginicola. 



The tips of the ceca come in very close association with the excretory 

 vesicle. Dollfus suspected the ceca connected with the vesicle, and all my 

 specimens suggest the same thing. Not even good frontal sections, how- 

 ever, conclusively show such a connection. The tip of each cecum becomes 

 very thin at a spot in contact with the vesicle, and there is probably a 

 fine connection. 



