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again, and in seven hours there were counted thirty-two cells which 
measured 8/* in diameter. In seven hours and a half, forty-one cells 
were counted, though there were probably more. 
The next change occurring in these cells is the acquirement of a 
flagellum. Each becomes ovoid, then pear-shaped, and from the 
more rounded end a flagellum is produced (fig. 18); there are always 
one or two parasites in each colony which remain spherical and 
develop no further. The colony of cells now takes on a lively 
motion. After a while the young trypanosomes become free and 
their movements increase in rapidity. 1 hey divide rapidly by 
splitting in their longitudinal axis, and thus in the field containing 
the original cells, and for many fields around are seen large numbers 
(io to 15 to a field) of young actively-moving trypanosomes. 
The young trypanosomes when first formed from the cell by the 
acquirement of a flagellum, had the shape and size (x 1,000) indicated 
