12G-H 



Canadian Arctic Expedition, 1913-18 



riocephalus. The body is depressed and ligulate, the margins being parallel for 

 almost the whole length and the posterior end gradually tapered to a diameter 

 slightly smaller than the tip of the scolex. 



On the whole these larvse resemble others that I have taken from cysts in 

 the wall of the stomach of Lota maculosa (LeSueur), the burbot, at Port Credit, 

 Ontario, near Toronto, and at Charlevoix, Michigan, and which may be similar 

 to those Nickerson (1906) found in fishes from the Great Lakes but suspected 

 might belong to species other than Di-phyllobothrium latum, the broad human 

 tapeworm. Incidentally the writer is conducting feeding experiments with the 

 larvae from the burbot in an endeavour to ascertain whether they are young of 

 D. latum and whether the cases of infection with this cestode in America can be 

 accounted for in this direction. 



Genus II Pyramicocephalus Monticelli 1890 



PjTatnicocephalus phocarum (Fabricius 1780) 



This species, described by Linstow (1905:14-15) under the name of P. antho- 

 cephalus (Rud.), was collected from Eriynaihus harhatiis (Erxleben), bearded 

 seal, as follows : 



THE OCCURRENCE OF PYRAMICOCEPHALUS PHOCARUM IN ERIOXATHUS 

 BARBATUS IN ARCTIC AMERICA. 



The largest specimen, one from Station 4Qt,u, measured 900 mm. in length 

 by 6 mm. in maximum width and its scolex, 4 mm. in length, 2 in width and 3 in 

 depth. Another from the same lot was 320 mm. by 5 in dimensions. The eggs, 

 when measured in the sections, were found to varj- from 58 to (35^ in length by 

 34 to 39 in width. Linstow gave their measurements as 65 by 39/i. 



Two larvaj, as well as adults, were -found in the material from Station 

 4:0t,u, while another larva was all that w;is taken from a specimen of common 

 rough seal, Phoca hispida Schreber, at ( 'ollinson point, Alaska, on September 7, 

 1913, at Station 27j. 



Subfamily III Cyathocephalinae Ltihe ISOO, c.p. Cooper 1919 



Genus I Cyathocephalus Ke.ssler 1868 



Cyathocephalus americanus Cooper 1917, e.p 



1917: Cyathocephalus americanus.. .Cooper 1917: 35 



(Type host, Coregonus clupeijorniis, whitefish, Georgian Bay, Lake 

 Huron) 



1919: Cyathocephalus americanus.. .Cooper 1919: 341 



Specific diagnosis. — With the characters of the genus. Small cestodes, 

 attaining a length of at least 16 mm. with a maximum breadth of 1-7 mm. 

 Scolex funnel-shaped, • 3 to ■ 9 mm. long and ■ 5 to 1 • 50 broad, with a revolute 

 margin. Neck 1-0 to 3-0 mm. in length. Segments twice as broad as long, 

 terminal one rounded. 



