122 
were present, though less numerous than the * stumpy,’ in blood 
inoculated into the goat. Case No. XXXIII. sheep XL. and m 
ill which the ‘ tadpole ' forms were reproduced. 
Rats were infected hy blood containing all forms. ‘Tadpole' 
forms predominated throughout the first few days of the disease, 
while the ‘ stumpy ’ became more numerous towards death. 'Long' 
forms were very rare, but were seen in those inoculated from an ox, 
a goat, and a guinea-pig; but they were not seen after inoculation 
from a dog or a second goat infection. It is to be remarked, 
however, that a thorough examination of all slides has not been 
possible. 
We have here, then, a trypanosnnie wliose prevailing type in 
na urally and experimentally infected animals is short, measuring 
only 9;5 to 15-3^, and from which there is a relative absence i/r 
Hagellum. This type under the influence of a different host, or u* 
a con itions in the same animal, assumes a distinct form whid 
asures rom 25 to 31/i in length, and possesses a flagellum which 
ava^M T ‘he knowledge a. preseu. 
Trvi ^ hesitation in ascribing the name 
d^m^"''" Dutton and Todd, ,904 to such . 
dimorphic organism. 
fresh cover-elasTtre^^^^^f^^*^ movement of this orgamsm 
effecl produced by the^pTssage a and 
and of no greater ma > ^ o^puscular displacement being transit 
hair across the su^al ^stih w” ^ “ 
one organism in the field by mo ‘ f ^"'Possible to retain a 
mechanical stage is not em,M ' 
its direction w'ith bewilH ‘ ^ Parasite crossing and alteri 
been kept for 
sluggish, and in fields wher*- ^ movements of some become mo 
to be due to a rotatorv m f scanty, progression is sei 
a wavy undulating memh ^ ° whole body, to the exclusion ■ 
flagellum. ^ ‘he vibrations or lashings of a fn 
* 
