246 E. A. MINCHIN. 
the larger forms the relative position of » and N varies 
greatly (see p. 190). Dividing stages were very rare; one is 
figured (fig. 180). 
The smears! from the proctodeum showed free font and 
all stages of encystment. The free forms show two types: 
(1) larger, broader forms, resembling the small forms seen in 
the black blood (figs. 183, 186); (2) slender, Herpetomonas- 
like forms with narrow bodies pointed posteriorly, and very 
long flagella, faintly stained (figs. 184, 185, 187, 188). The 
encysting forms, though forming a continuous series, may be 
divided into (3) forms with flagellum recognisable (fig. 189- 
193); (4) pear-shaped with flagellum retracted (figs. 194— 
198) ; (5) ripe cysts, more or less spherical (figs. 199-202). 
A count gave the following results : 
iF 2. 3. 4, 5. Cenee 
Encyst-  Fla- 
Ordi- ing gellum Ripe Round Dividing 
H-like. : te 
nary. flagellum re- cysts. forms. forms. 
present. tracted. 
Number . 412 60 38 62 30 2 1 
—— 
bo 
Percentage. 17:48 25°58 16°22 26°42 12:82 -84 -4 
Nov. 15th (288 hours after infection)—Two flies, the 
last survivors of the batch, were dissected, one a male, the 
other a female, containing a larva. Both were gorged with 
blood, red in the stomach, black in the intestine, of both the 
proventriculus, stomach, intestine, proctodeeum, genitalia, and 
in the female the larva were examined, but no trypanosomes 
were found. 
Stomoxys Hxperiments. 
Nov. 17th.—A batch of Stomoxys sp. fed on Monkey 
510, which was showing a fair number of trypanosomes. 
Noy. 18th.—Four flies dissected and examined ; in all try- 
Although the proctodeum contained no blood, my smears show a few 
blood-corpuscles. I think these must have.come from the serum used in 
making the preparations. 
2 One, and only one, of this number had z behind WN. 
