PARASITIC WORMS LRII'KU AND ATKINSON. 30 



surface, behind the oral sucker, from which it is separated by a lip. It is at a deeper 

 level than the sucker. It consists of a thick ring surrounding the cirrus-opening 

 and the wider vaginal opening (text-tig. ">,/<). The yolk-glands (I'l. III. fig. Ifi, //) vary 

 greatly in number, from ten to eighteen occurring on either side. The variation in 

 the sixe and shape of the ovary (Fig. Ui, nr) is also marked, as will be seen Irom 

 text -figure (i (a. b, c. d. e, f. g). Tin- shell-gland is a. thin structure immediately in 

 front of the ovarv. and is composed of large cells with a small nucleus. 



The posterior ending of the rugae seems to be in a small punctate opening. 



The occurrence of this parasite may serve to throw some light on the much 

 discussed (piestion of the specific identity of whales found in widely separated localities. 



K;. (>. Ogmogagter plicatus : The ovary, outlined from seven specimens, to show variation in contour. 



The occurrence of Cirixx/i-iiin/it crassicauda in a Northern Rorqual, as described 

 liy ( 'replin, and in a specimen of a Humpback (Megaptera) caught off New Zealand, 

 also has some bearing upon this matter. 



CESTODA. 



( )RDER PSEUDOPHYLLIDEA. 

 FAM. BUTHRIOCEPHALIDAE. 



/)!/ii>f/tri<i<;'ji/i<l/i/x, Liihe. IS'.)'.). 



I'.). Dibothriocephalus mcibilis, Keiinie and Reid, 1!)1 % 2. 



This minute (Jestode occurred in large quantities in the stomach and in the upper 

 part of the small intestine of all the specimens of Weddell's Seal examined. 



The average length, including the head, is I'd mm. There is no neck, and 

 segmentation liegins immediately In-hind the head. The segments increase in breadth 

 about the middle, and diminish, tending to become more elongate, towards the tail-end. 



