S2 



TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



Acanthobothrium and differs in that the accessory suckers 

 are absent. It is similar to the latter forms in that double 

 hooks are present, one pair on each bothrium. The hooks 

 are represented in fig. 2 13. Each consists of two long, 

 slightly curved, slender spines fused together by their 

 bases. This fused median part is not nearly so prominent 



Vagina--- 



Genital-- 

 aperture 



JTes tis 



Vitellarium 



i/esicula 

 seminans 



ma 



Vag 



ma 



Recebtaculurp- 

 r 5emims 



Fig. 3. Prosthecobothrium dujardinii, (van Beneden); Terminal 

 proglottis. Mag. 51 dia. 



as is represented in van Beneden's figure. The hooks 



stand well out from the face of the bothrium. 



The terminal proglottis — the only one in the strobila 



which was mature— is represented in fig. '■>. The posterior 



