OX THE TEYPANOSOME OF THE LITTLE OWL. 
167 
Using the standards of measurement previously adopted 
(loc. c it.), the total length of these forms, as they appear on 
smears made by the first (Romanowsky) method (figs. 1-3, 
14), is from 26 to 28 /u, and the greatest width 3 to 4 n, while 
the length of the free flagellum is usually about 8 to 9J /u. 
The troplionucleus is situated about the middle of the body, 
or at most is only slightly nearer to the aflagellar end than to 
the other. 
Comparing these forms as they are seen in wet films (i.e. 
films made by the second method), the length of the parasite 
appears uniformly somewhat less, averaging about 25 jjl. 
There is no doubt that the body of the trypanosome is always 
rather contracted or shrunk by the wet method of prepara- 
tion. This can be clearly seen to be the case by comparing 
figs. 32-35 of these small parasites on wet films with the 
figures of individuals of the same type on Giemsa smears. It 
will be noticed also that, in the former case, the flagellar 
border of the parasite frequently appears more crinkled and 
ang’ular-looking than in the individual on “dry” smears; this 
being the result of a shortening of the body cytoplasm to a 
greater extent than the flagellar border (though the latter, 
and of course the free flagellum, is also somewhat contracted). 
The next type of the parasite, the medium-sized form (figs. 
7, 8, 20, and 21), is distinguished by its long, finely tapering 
aflagellar region, and also by the conspicuous undulating 
membrane, the folds of which are broad and high. The 
folds, it may be noted, frequently show the delicate endo- 
plasmic intrusion, as described in the first memoir. The 
aflagellar end may be very narrow and attenuated (figs. 7 and 
20). The free flagellum is relatively long. The entire length 
of these forms, in the above typical instances, is from 44-47 p, 
the greatest width varies from 5 to 5 A ju, the length of the free 
flagellum is 11 to 13 /x, while the aflagellar prolongation of the 
body, measured from the kineto nucleus, is usually 5 to 6J , h 
but in the individual of fig. 7 it is as much as 9 fx. In this 
type the trophonucleus is always in the aflagellar half of the 
the body, i.e. it is nearer to the kinetonucleus than to the 
