SEA-FISHERIES LABORATORY. 



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free, cut, or frilled as the worm grows weak, or when 

 placed in fresh water or alcohol." 



From this diagnosis it appears that Crossobothrium 

 is closely related to Phyllobothrium, and indeed the 

 cestode figured here resembles greatly Ph. thridax. The 



Rostellum 



BoThriui 



HM , 



Auxiliary 

 acetabulum 



Fig. 18. Crossobothrium laciniatum, Linton. Scolex seen from above. 



Mag. 100 dia. 



differences, however which Linton emphasises as consti- 

 tuting the distinctive features of the genus are (1) the 

 bothria pedicelled here, instead of being sessile as in 

 Phyllobothrium, and (2) the absence of a distinct neck. 



I refer a worm obtained from the large intestine 

 of Rata batis very doubtfully to this species. The 

 specimen is indeed very different in appearance from 

 Ph. thridax, but in dealing with such highly variable 

 structures as the bothria of these cestodes too much 



