180 SPOLIA ZEYLAT^^ICA. 



a flagellum from their blunt ends. I have over and over again 

 watched this part of the development under an immersion lens, and 

 all that I can say is that a little blunt stiff process simply appears. 

 This gradually lengthens and becomes motile, but at first it is quite 

 unable to move the body of the creature. Finally, it can be observed 

 that the attachment of the flageUum is no longer quite at the blunt 

 end, but has shifted slightly to one side, and a small protoplasmic 

 ridge, which I take to be the first sign of the membrane, is to be 

 detected. The four little flagellates separate and move actively 

 about. This short description does not take into account the 

 considerable variation in detail which occurs. This tr3rpanosome 

 is true to the versatile traditions of the genus, and many slight 

 differences, especially in the relative times at which the processes 

 occur, are to be observed. 



The intermediate host for this species is another little water leech. 

 The trypanosome undergoes the above development at once upon 

 being taken into the crop of the leech, and further divisions after 

 the two mentioned seem to occur. The creature finally develops 

 into a slender trypanosome of very varying size with a narrow 

 membrane and a short flagellum ; the Idnetonucleus very generally 

 lies very close and just anterior to the trophonucleus. It is, I 

 think, important to note that they are to be found in large numbers 

 in infected leeches at the close of digestion, when there is no blood 

 left in the alimentary tract. 



Many interesting experiments were tried with the big horse leech, 

 but I have not space to describe them here. The horse leech, by 

 the way, has distinctly catholic tastes, as one specimen started to 

 feed eagerly upon my owti hand, and upon being persuaded to desist, 

 took equally kindly to the tortoise. In the blood of the Emyda 

 vittata, the tr3rpanosome infection is almost invariably associated 

 with a haemogregarine infection. 



The haemogregarine shows two distinct types — a long slender 

 recurved individual with pale faintly reticulate protoplasm and a 

 dense nucleus ; and a broad type with deep blue staining protoplasm 

 and a very characteristic loose meshed nucleus. This nucleus is 

 not like that of any other hsemogregarine that I have ever seen,. and 

 is much more suggestive of the nucleus of a large resting trypano- 

 some, not that I wish to imply that there is a connection between 

 the two infections. 



These broad hsemogregarines show a very interesting feature, 

 namely, two large oval bodies which stain from a pale pink to a deep 

 slightly brown red with Giemsa's stain. They are not present in 

 all the broad specimens, especially not in the smaller ones, but they 

 are a very characteristic feature of the larger broad forms. At 

 first they were very suggestive of structures with kinetonuclear 

 affinities, but from their highly refractive appearance in the live 

 state and the variability in their staining properties, I am rather 



