J. H. WOODGER 



347 



The total number of infected flies found was only five out of the 

 338 dissected from the localities mentioned (i.e. all except British and 

 Indian latrines), — a percentage of nearly 1-5 per cent. 



5. Description of the Parasite. 



The following description and accompanying figures are taken from 

 live specimens examined fresh in saline. Three developmental stages are 



Fig. 1 a. The parasite in Stage I : S, scolex, X, points at which constrictions are appearing. 



b. Parasite in Stage II: 8, scolex, V, vesicle. 



c. The same parasite, drawn one hour later. 



represented, the specimens of each being from different flies, since all 

 the parasites from the same fly were found to be in approximately the 

 same stage. All figures magnified approximately 145 times. 



Stage I. Fig. 1 a represents the earliest stage seen. The cyst-wall 

 enclosing the embryo appears to consist of a single transparent, gela- 



23—2 



