1912.] On the Extrusion of Granules by Trypanosomes. 



385 



in which the further development may proceed. The body may enlarge 

 slightly, develop a true flagellum from the neighbourhood of the micro- 

 nucleus, and then become longer. This increase in length continues, and 

 the macro- and micro-nucleus in this process become further separated ; the 

 flagellum comes to lie along the margin, and this form can now be recognised 

 as an early immature trypanosome. There is no undulating membrane, but 

 development proceeds till the adult form is reached. 



On the other hand, the circular form may enlarge to a greater degree, 

 and show a larger amount of a pale-blue staining cytoplasm that seems 

 characteristic of young forms. The nucleus and micronucleus then undergo 

 division by schizogony, but remain within the single mass of cytoplasm. 

 The time of appearance of the flagellum seems to be variable, but ultimately 

 all the pairs of macro- or micro-nuclei come to have a flagellum with a fan- 

 shaped origin usually projecting beyond the margin of the cytoplasm. 



Plate 11 shows forms with two, four, and eight macro- and micro-nuclei 

 and flagella. We have seen indications of similar forms in vital pre- 

 parations, but the latter cannot show the same detail as fixed and stained 

 preparations. We have no knowledge as to the conditions which determine 

 either of these events — possibly in the latter case there may be some sexual 

 process either in the cells or fluids. 



Many of these bodies are identical with the Plimmer and Bradford bodies, 

 which they described in 1902,* and we have found them in preparations 

 made from many different animals and from man, of glands, internal organs 

 and bone-marrow. They show when living undoubted motility, but the 

 early granule shows much more active movements than these later forms. 

 The fact of their showing this vital property, however, precludes any possibility 

 of their being degeneration forms. 



In a few cases of sleeping sickness in man some other bodies have been 

 seen by the vital method in fluid obtained by liver puncture. In the 

 majority of instances some blood was mixed with the liver juice ; this diluted 

 the fluid and the bodies were very scanty, but the appearances presented 

 suggested that some process of division was going on. Protoplasmic masses 

 were seen containing four or eight small ovoid bodies taking on nuclear 

 stain, but there was no nuclear differentiation. These were seen only in wet 

 preparations, and could not be preserved. 



Another form was seen as a fusiform body lying round a segment of the 

 periphery, apparently of a mononuclear cell. It suggested an immature 

 trypanosome, and this idea was confirmed by the presence of similar bodies 

 free in the liver juice showing slight sluggish movement. 



* 'Quart. Journ. Micros. Sci./ February, 1902. 



