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Note on Developmental Forms of Trypanosoma brucei (pecaudi) in 

 the Internal Organs, Axillary Glands and Bone-marrow of 

 the Gerbil (Gerbillus pygargus). 



JBy George Buchanan, Senior Laboratory Assistant, Wellcome Tropical 

 Kesearch Laboratories, Gordon College, Khartoum. 



{Communicated by Col. Sir David Bruce, C.B., F.B.S. Beceived May 12, — Bead 

 June 15, 1911.) 



[Plate 3.] 



The transmission and maintenance of the trypanosome strains being under 

 my care, ample opportunities were afforded of noting the progress of the 

 disease induced by them in experimental animals and the structural changes 

 in the trypanosomes themselves at varying periods. But it was mainly the 

 cultural work associated with this trypanosome that led to further investiga- 

 tion of these developmental forms and thereby established the observations 

 forming the subject of this note. 



On beginning the culture work, inability to recognise if certain forms met 

 with in cultures were either developmental or degenerative phases, suggested 

 a study of the changes which the parasite undergoes, both in the body of the 

 gerbil after death and in citrated blood, and the comparison of these changes 

 with the forms found in Novy and MacNeal and Nicolle's media. With this 

 in view, a gerbil was inoculated with infected blood and chloroformed on the 

 fifth day after injection. Cultures from the heart's blood and smears from 

 the various organs were made, all being examined at regular intervals for 

 comparison. Light was thereby thrown on the point in question, but, in 

 addition to this, attention was drawn to what undoubtedly looked like 

 trypanosome forms in the red blood corpuscles in the spleen. Some of these 

 were identical with those figured by Chagas in his paper on Schizotrypanum 

 cruzi, which appeared at the time this work was being conducted. 



In order to confirm the observations made, a series of inoculations was 

 carried out in gerbils. In the first of the series, five gerbils were employed, 

 these receiving subcutaneous inoculation in the flanks, In each of the two 

 later series, however, it was found necessary to use eight gerbils at least, the 

 injection being given intraperitoneally as recommended by Chagas. The 

 amount of infected blood in citrate inoculated into each animal was 

 10 minims, all the eight forming one series receiving the injection at the 

 same time. A gerbil of the series was then chloroformed on each succeeding 



