16 PROCEEDINGS OF THE NATIONAL MUSEUM vol. 81 



acetabulum the follicles form a transverse dorsal band across body ; 

 ventrally the follicles do not encroach on the testicular and uterine 

 fields; caudad of the testes the follicles coalesce in the median line 

 and completely fill the posttesticular zone. The uterus extends 

 anteriorly from Mehlis's gland in transverse loops to the acetabulum, 

 where it terminates in a well-developed vagina, the cuticular lining 

 of which is armed with spines similar to those of the cirrus. Eggs 

 91/x to lOOfx long by 54/* to 58fi wide, triangular in cross section, and 

 having a thickened posterior pole. 



Hosts. — Erignathus harbatus (= Phoca harhata) ; Phoca klspida. 



Location. — Gall bladder and liver. 



Distribution. — Europe (west coasts of Greenland and Spits- 

 bergen) ; North America (Canada — Bernard Harbor, Northwest Ter- 

 ritories — according to Cooper, 1921). 



ORTHOSPLANCHNUS FRATERCULUS Odhner, 1905 

 Plate 4, Figxtre 19 



Description. — rthosplanchnus : Body almost cylindrical, 3 mm to 

 4 mm long by 500/a to 600//, wide. Cuticular spines more abundant 

 than in O. arcticus. Oral sucker 370/^ to 440/a in diameter; aceta- 

 bulum 400/i, to 500/x in diameter. Pharynx 300/a to 330/a long by 200/i, 

 wide; esophagus 220/a long. Cirrus pouch as in 0. arcticus. Testes 

 deeply indented. Vitellaria do not unite to form a dorsal band an- 

 terior to acetabulum, and ventrally they encroach on the testicular 

 and uterine fields. Other characters as in O. arcticus. 



Hosts. — Odohenus rosniarusj Erignathus barbatu^. 



Location. — Gall bladder. 



Distribution. — Europe (Spitsbergen). 



Genus SYNTHESIUM Stunkard and Alvey, 1930 



Generic diagnosis. — Campulinae : Body long and slender. Suckers 

 of equal size. Digestive system as in Campula. Cirrus pouch long 

 and slender, inclosing seminal vesicle, pars prostatica, and spiny 

 cirrus; testes deeply lobed as in Lecithodesmus. Ovary spherical, 

 pretesticular ; vitellaria consist of small, grapelike clusters of fol- 

 licles and do not extend anteriorly as far as acetabulum ; uterus with 

 few coils; vagina lined with spines. Eggs with polar thickening. 

 Parasitic in intestine of cetaceans. 



Type species. — Synthesium tursionis (Marchi, 1873). 



SYNTHESIUM TURSIONIS (Marchi, 1873). new combination 



Plate 5, Figures 20-21 



Synonyms. — Distomuin tursionis Marchi, 1873, p. 304; Distonvmn 

 longissimum- Poirier, 1886, pp. 29-30, not D. longissimum von Linstow, 



