3 6 1 
Detection of Trypanosomes. —The most certain 
method is by culture ; this may be positive when 
repeated blood examination has been negative. Dani- 
lewsky states that, while rare in the blood (as is generally 
the case), trypanosomes may be abundant in the bone 
marrow. 
Trypanosomes of Invertebrates 
1. 7 ". grayi. —p. 342. 
2. T. tullochi. —p. 343. 
3. 7 ". piscicolae. —Common in leeches, together 
with trypanoplasmata. 
4. 7 " . Christopher si. —Found in one specimen of 
Eu. sanguineus (the Indian dog-tick). It is larger than 
Herpetomonas and Crithidia forms. 25 by 2*4/c 
Flagellum 8-12/c U.M. well developed. Blepharo- 
plast close to the nucleus. 
Flagellates in the Gut of Insects, etc. 
Besides the true trypanosomes natural to the 
tsetse fly already described, allied flagellates are found 
in the gut of various insects. These are generally 
assigned to two different genera, though the definition 
of these genera is at present somewhat vague. 
Crithidia. —Includes two forms : (a) short, oval 
or pyriform flagellates, rounded posteriorly, somewhat 
truncated anteriorly, with a short straight flagellum 
(‘pears’). The nucleus and blepharoplast are posterior. 
(b) Longer forms, rounded at each end or tapering 
slightly at one end (not at both as in Herpetomonas), 
with a long flagellum (‘cigars’). The nucleus is median 
and the blepharoplast half-way between it and the 
anterior end. The flagellum (may have a fine 
extension of the periplast over it. There is no 
