It is possible, as Swellengrebel (1908) suggested, that the stainable 
line is a form of degeneration. However, on the exact significance 
of the stainable band seen in such trypanosomes I prefer not to 
pronounce a definite opinion at present. 
THE METAMORPHOSIS OF LATENT BODIES 
INTO TRYPANOSOMES 
This process was observed in life on several occasions, though 
the complete passage from a rounded body to a fully flagellate 
moving trypanosome was only rarely seen (three times), for it is 
difficult to imitate precisely the natural conditions favourable to 
such a metamorphosis. However, by taking rounded bodies, usually 
obtained from the spleen of an infected rat, in a little physiological 
salt solution, and adding thereto an equal quantity of fresh 
normal, uninfected) rat’s blood, some of the rounded bodies were 
seen on a warm stage (25° to 3s 0 C.) to grow, each becoming larger 
and sending out a process (text-fig. 2). This pseudopodium-like 
process lengthens, and a flagellum is formed from an area close t( 
I f xi ni,. 2 represents diagrammatically the metamorphosis of a rounded, latent or non-flagdh 1 ' 
,nto . a fl . a ge»ate trypanosome (T. gambieme). The rounded bodies, obtained fro® 
. j f , en 0 . an tnfcctcd rat, were placed in warm, fresh, uninfected rat’s blood and watt - - 
e nllcr °scope. 7 lie total time taken for the metamorphosis was about one hour. 
