672 MURIEL ROBERTSON. 
these early phases. In some cases the animal broadens 
considerably and adopts the spiral shape, the turns of the 
spiral fuse together, and the most grotesque dumpy creature 
is produced, which keeps up a slow corkscrew or revolving 
motion (text-fig. 2). 
Another appearance of rather a curious character is that 
where the screw movement backwards and forwards is kept 
up but very slowly, and the body no longer preserves its 
Trxt-F1G. 1—Sketches of live Trypanosomes to show early 
phases in the rounding off of the parasites. A and B are one 
individual, so also ¢ and pb. 
regular fusiform shape, but bulges now in one direction now 
in another (text-fig. 1, a and s). The movement is difficult 
to convey, but is best described as very metabolic euglenoid 
mevement associated with a slow screwing backwards and 
forwards. During this movement the myonemeta can still 
be very clearly seen, and besides these at the non-flagellate 
end circumferential lines running round the creature can be 
seen, especially during the screw forward. 
