154 



On proservation by killing in water anrl picklinp: in five 

 per cent, formalin, the whole strobila is more transparent 

 and thinner in the tnrbot than in the brill, and in the 

 latter case the edg-es of the proglottides are very nsually 

 more or less crennlated. These differences are very 

 obvious and are g-enerally constant. The smaller head 

 of the cestode from the brill is, in particular, a very 

 striking- jioint of diiference. 



Teteafhyllidea. 



Oncobotheiid^. 



Oncobothrium uncinatum, Rud (Figs 12). 



Hosts : Raid rnacalatd and R. microceUata, Cardigan 

 Bav : and /?. cfacafa, Bahama Bank. 



Fj(,. 12. Oncobuthriiiin uncinatiiin. RucTolphi. A : the scolex 

 seen from above, mag. 82 dia. ; B: the scolex seen from the side, 

 mag. 2] dia. : C : hooks. 



This species has been recorded by van Beneden from 

 the coasts of Belgium as a parasite of Raia clavata, and 

 Trygon ■pastinaca, while Linton records it from the 

 Wood's Hole region from Trygon ceutrura. According to 

 van Beneden it is very rare. I have obtained five 

 specimens altogether. 



