164 E. A. MINCHIN. 
Since my return to England, my two assistants, Dr. J. D. 
Thomson and Dr. H. M. Woodcock, have rendered me much 
service in various ways, and Miss H. Y. Thomson has been of 
great assistance in the tedious task of searching through 
blood-films for trypanosomes and making counts of them. 
To each and all of these I desire to express my obligations 
and return my best thanks. 
Methods of investigation.—I commenced my work, as 
I have said, by making a study of anatomy of Glossina 
palpalis. In undertaking this I was influenced largely by 
Schaudinn’s work (40) on Trypanosoma noctue, in 
which he describes extensive migrations of the trypanosomes | 
in the body of the invertebrate host. In tsetse-flies, how- 
ever, I never found trypanosomes outside the alimentary 
canal, in spite of much searching; in this point my results 
agree with those of Stuhlmann (41). 
My report on the anatomy of the fly (27) sonteined some 
errors which I desire to correct ; they have been corrected in 
the reprint in the Reports of the Sleeping Sickness Commis- 
sion. All through I used the term stomach for what should 
have been called the proventriculus; in this memoir I 
shall use the latter term. The true stomach in Glossina 
is represented by the first part of the digestive tract in the 
abdomen, that is to say, by the coils which in my figures and | 
description were numbered 5, 6, 7. It is this region which 
becomes congested with blood after feeding, and in which 
the blood retains its bright red colour. From the stomach 
the blood passes into the next coils of the ‘digestive tract, 
which constitute the true intestine, and here it becomes 
blackish in colour. Hence we may conveniently speak of the 
red blood, meaning that in the stomach, and the black blood, 
meaning that in the intestine proper. The red blood is thick 
and jelly-lke, very difficult to smear out unless broken up 
with salt-citrate solution!; the black blood, on the contrary, 
is very fluid and watery, the number of corpuscles i 18 more or 
1 Made up as recommended by Laveran and Mesnil (23) ; ; ‘5 gr. sodium 
chlorine + °5 gr. sodium citrate + 100 cc. HO. 
