J. H. WOODGKR 



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is entirely separated from the parasite. The head, attached by a narrow- 

 neck to the somewhat shrunken bladder, bears four suckers and a 

 club-shaped rostellum, armed with a single row of small booklets. 



It will be noted that there are certain differences between the two 

 specimens figured in Fig. 3. The hooklets are smaller and more numerous 

 in one than in the other; and the shape of the rostellum is also different 

 in the two specimens, but this is probably merely the effect of different 

 conditions of contraction. The separated vesicle V also is smaller in 

 one than in the other. 



Fig. 3. Two mature cysticercoids (Stage III) from the same fly; with vesicle lying free 

 in cavity of cyst. 



6. Feeding Experiments. 



With such a small amount of material very little could be done in 

 the direction of experimentally infecting a vertebrate host, but the few 

 experiments that were tried are perhaps worth mentioning. 



On April 2, 1918, some fresh cysts were introduced by means of 

 a pipette into the gullet of a lizard (Ophiops elegans var. meizolepis). 

 The animal died on the 6th of the same month, probably as a result of 

 too much exposure to the sun; examination of intestine and faeces 

 revealed nothing. 



On April 23 a similar attempt was made to infect two other lizards 

 of the same species, also with negative results. 



On April 24 some fresh cysts were introduced into the gullet of a 

 young rabbit. Twelve examinations in the course of 25 days of the 



