TRYPANOSOMIASIS IN THE ANGLO-EGYPTIAN SUDAN 157 



the examination liave already been described (p. 139). Is it possible that a rapid destruction 

 of the parasites occurred, resulting in a liberation of the toxines, the stress of which fell 

 upon the central nervous system ? 



Exp. 20. Gerbil 10. Weight 34 grams. April Sfl>. Found infected. Mostly long 

 forms. 



April 9ffi. 10 in. sat. sol. chrysoidine snbcntaneonsly. 



Apnl 10th. Fresh and stained films examined. No change noted. 10 m. given. 



April llth. No change noted. 15 m. given. 



Apnl 12th. No increase in number. Very few long forms present. No marked 

 change in appearance. 20 m. given. 



April I'Sth. Marked change. Many involution forms. In the fresh blood few forms 

 were seen and these were very sluggish, not moving about at all, but all stationary, and 

 presenting what may be called " rippling " movements. Vacuolation and change in shape 

 noted on staining. Animal well. 20 m. given. 



April lith. Only two trypanosomes found per cover-slip preparation. These were 

 long but sluggish forms. On staining, a decrease in number was evident. 20 m. given. 



April Ibth. An evident increase. Trypanosomes more lively. Some involution forms. 

 20 m. given. 



April IQth. Animal well and lively, 20 m. given. 



April 18fh. Blood swarming. Forms with broad posterior ends and huge undulating 

 membranes —probably prior to division — found. Animal fairly well. 



April 19fh. Found dead — decomposing. 



Foxt-nwrtfm. Bacterial invasion. Spleen enlarged. It may be mentioned here that 

 these chrysoidine solutions were centrifuged before use. 



Exp. 22. Gerbil 12. This animal was treated with the so-called soluble chrysoidine — 

 chrysoidine extra of the Anilin Manufacturing Company of Berlin, being the same preparation 

 as employed by Weyl in his pharmacological experiments. 



April 15fh. 10 ni. of a saturated solution of soluble chrysoidine given on this the 

 r)th day after inoculation. Blood swarming. 



April Idfh. Blood full of trypanosomes, mostlv broad, sluggish forms. On staining, 

 forms in process of division and some with huge undulating membranes seen. 15 m. given. 



Ajiril llth. Motionless forms present in the blood. Also curious involution types. 

 Many active parasites seen. 20 m. given. 



April 18'//. No change. 20 m. given. 



April 19th. A very interesting blood. In fresh films many motionless forms seen 

 On staining, normal looking trypanosomes were apparent together with many curious 

 dead forms ; some spherical, some with very blunt posterior ends, and many vacuolated. 

 Leucocytosis was present, but no phagocytosis was observed. 20 m. given. 



April 20th. Much as on the 19th, but the peculiar forms still more abundant. The 

 animal died in tlie afternoon. 



Pust-morfeiH. The tissues generally, and specially the brain, spinal-cord and nerve 

 trunks were stained yellow. The spleen was slightly enlarged. No redenm or hypertrophieil 

 glands. 



Smeors. The heart's blood contained the remarkable forms above mentioned. These 

 were also present in the liver smear together with forms very like Leishman-Donovan bodies 

 and apparently the young i-esistant types described by Lingard. The nuiin rlifterence from 



