96 
occurrence, and 1 nly met with than the other species 
Sometimes one would obtain two or three stomachs consecu- 
tively which containe megastoma, an any 
was more rarely met with than H. microstoma, H. 
being the most common, and usually found in each stomach 
examined. UT 
or the purposes of the subject under investigation it 
was considered that any detailed study of the adult forms 
was unlikely to give any useful information. 
o detailed study of the development of the worm larvae 
in the*fly larvae, pupae, and adults was made, as, oi neces- 
sity, a limit had to be placed on the scope of the investigation. 
The following is a brief outline of the observations made 
on the embryos and larvae of the three species of Habronema 
and examination of adult flies: — 
THE LIFE-HISTORY OF Habronema muscae (Carter, 1861). 
Ransom has already shown that embryos of Habronema 
muscae, passed along with the faeces of the horse, gain entrance 
to the larvae of Musca domestica, probably through being 
swallowed by the fly larvae. The embryos gain the body 
e 
observed may have been larvae of Habronema megastoma. 
i experiments undertaken in 1916 under artificial con- 
ditions conti ansom's conclusions. i 
|» Embryos of H. muscae.—Embryos that have been pas". 
out from the female have been found to be enclosed in à thin 
(o mensure from 
