PARASITISM IN RELATION TO BIRDS. 49 



Family Hymenolepidid^;, genus Monopylidium. 

 Generic Diagnosis. 



DlPHYLLIN^. 



(1) Kostellum armed with a double or single crown of hooks. 



(2) A single set of reproductive organs in each segment. 



(3) Genital pores irregularly alternate, rarely unilateral. 



(4) Genital canals pass between the longitudinal excretory 



vessels and dorsal of the longitudinal nerve, or dorsal 

 of both excretory vessels. 



(5) Testicles numerous (20-40 or more) behind the female 



glands, or also lateral on both sides of the latter. 



(6) Vas deferens coiled ; seminal vesicle absent. 



(7) Uterus breaks down into egg-capsules, each containing 



one or several eggs. 

 Adults in birds : Starling. 



Family Hymenolepididje, genus Anomat-enia (Cohn). 



Generic Diagnosis. 



Diphyllin^. 



(1) Eostellum with double crown of hooks, with long dorsal 

 and short neutral root and long blade. 



(2) Genital pores irregularly alternate near the anterior 



margin. 



(3) Genital canals pass between the longitudinal excretory 



vessels and dorsal of the nerve. 



(4) Vas deferens coiled ; seminal vesicle absent. 



(5) Testicles numerous in posterior position of segment. 



(6) Uterus sac-like. 



Adults in birds and mammals : Thrush. 



Type species : — (1) Anomatcenia constricta in Thrush ; (2) A. 

 nymphaa in Curlew. 



As will be seen from the above, the Starling is the bird which 

 seems to be infested by the greatest variety of Cestodes. 



The number of Cestodes collected was numerous, but the 

 identification became very uncertain, due to the difficulty of 

 making out the precise positions of the genital ducts and genital 

 organs in general, owing to the fact that time did not permit of 

 the microtoming of the segments, which in the majority of cases 

 is essential for identification of the species. 



