3^3 
visible in most Herpetomonas forms, so that practically 
a spindle-shaped flagellate, with anterior blepharoplast, 
is a Herpetomonas. The undulating membrane is, if 
present, only slightly developed and difficult to see. 
There is, therefore, little, if any difference, between a 
Herpetomonas and the forms taken on by trypanosomes 
in culture. Further, the Herpetomonas assumes a 
resting gregarine form, attached to epithelial cells of 
the gut by their flagella, e.g., in the pyloric dilatation of 
the larva, developing into free forms in the mid-gut 
of the mosquito. 
1. H. muscae-domesticae (Burnett) in the gut 
of house flies, e.g., Muse a domestic a, Homalomyia 
scalaris, etc. Also a similar one in the gut of 
Stomoxys calcitrans. 
2. H. sarcophagae (Prowazek), in Sarcophaga 
haemorrhoidalis, the meat-fly. 
3. H. algeriense , in the gut of C. pipiens and S. 
calopus. It is 12 by 2*5/4, flagellum 4*5/4, blepharo¬ 
plast posterior. Non-motile forms also occur, 5*5/4 
in diameter, with flagellum 17/4. Resting (gregarine) 
forms without flagellum also occur. 
4. H. culicis (Novyl—-In C. pipiens , etc. Actively 
motile: (1) long, 25-35/4 by 1 -1 *5/^; flagellum, 
5-10/4; (2) medium, 15-25 by 1 *5-2*5/4 ; flagellum, 
3-8/4 (male type) ; (4) Wide form, 20 by 2 *5 -3/4 ; 
flagellum, 5-8/4 (female type). They all have a double 
body (diplosome) situate posteriorly (Fig. 111). 
These forms also become spherical, about 5/4 in 
diameter. H. culicis can be grown on Novy and 
McNeal’s medium. The forms in culture resemble 
those in the mosquito. 
5. H. pulicis. —In the gut of fleas; P. cleopatrae 
(Balfour) and Ctenocephalus felis (Patton). 
6. H. subulata. —In Pabanus glaucopis and Hae- 
