ART. 13 TREMATODE PARASITES OF MARINE MAMMALS PRICE 13 



Genus ZALOPHOTR'EMA Stunkard and Alvey, 1929 



Generic diagnosis. — Campulinae : Body flattened, somewhat atten- 

 uated posteriorly and rounded anteriorly. Oral sucker terminal, 

 larger than acetabulum. Intestinal ceca as in Gampula; posterior 

 ceca without anal openings. Excretory pore terminal ; excretory 

 vesicle tubular and extending to ovary. Cirrus pouch extending 

 caudad of ovary; cirrus unarmed. Ovary indented but not lobed, 

 pretesticular and slightly to right of median line; seminal receptacle 

 absent; Laurer's canal present. Vitellaria as in Camjyula. Uterus 

 coiled. Eggs with thickening at posterior pole, circular in cross 

 section. Parasites of pinnipeds. 



Type species. — Zalophotreina hepaticum Stunkard and Alvey, 

 1929. 



ZALOPHOTREMA HEPATICUM Stunkard and Alvey, 1929 



Plate 3, Figures 13, 14 



Description. — Zalophotrema: Body elongate and flattened dorso- 

 ventrally, 11 to 13 mm long by 3 to 3.6 mm wide, and from 

 600/A to 1 mm thick, the thickness decreasing abruptly imme- 

 diately caudad of testes. Cuticle armed with spines, which vary 

 from 14^ to 35/i, in length. Oral sucker 700/^ to 800//, long by 800/a 

 to 1 mm wide; oral opening slightly subterminal. Acetabulum 

 570/A to 620/A in diameter, situated one-fifth to one-sixth of the body 

 length from the anterior end. Pharynx piriform, 550/u, to 600/x long 

 by 380ja to 420/A wide. The digestive system bifurcates a short dis- 

 tance caudad of pharynx into two laterally directed branches, each 

 of which bifurcates into a short anterior and a long posterior cecum ; 

 the anterior ceca terminate near the anterior end of pharnyx; the 

 posterior ceca are provided with many median and lateral diverticula, 

 and terminate near the posterior end of the body. Excretory pore 

 terminal ; excretory vesicle extending anteriorly as a simple sac to 

 the region of the ootype. Cirrus pouch relatively weakly developed, 

 extending from genital pore to level of ovary, according to Stunkard 

 and Alvey (1930), and containing a coiled seminal vesicle, prostate 

 cells, and an unarmed cirrus. Testes large and deeply lobed, tandem 

 in position, and occupying the equatorial third of body. Ovary 

 lobed, 500/A long by 1 mm wide, situated at caudal end of anterior 

 third of body ; Mehlis's gland posterior and dorsal to ovary ; seminal 

 receptacle absent; Laurer's canal present. The vitellaria consist of 

 masses of follicles, which extend in the lateral areas of the body 

 from the level of the pharynx to the posterior end ; they tend to be 

 dorsal in position in the anterior part of body, almost meeting in 

 the median line cephalad of genital pore, while caudad of testes 

 they are both dorsal and ventral in position and invade the median 



