THE HJIMOFLAGELLATES. 173 



comes to lie between the ectoplasm and the endoplasm of the 

 Trypanosome/ becoming greatly distended and elongated, 

 and more or less spindle-shaped (fig. 33 c). The nucleus of 

 the corpuscle also becomes drawn out and band-like. The 

 ectoplasm of the parasite is apparently then transformed into 

 a protective envelope, and finally cast off with the remains of 

 the leucocyte at the close of this period. 



There are, as well, one or two important observations show- 

 ing that Mammalian Trypauosomes also may come into rela- 

 tion with the blood-corpuscles. Voges (119) often noticed 

 individuals of T. equinu m attached by the non-flagellate end, 

 and also by the side (cf. Trypanomorpha nocture above), 

 to red blood-corpuscles. In some cases, moreover, it appeared 

 as if the parasite had actually penetrated the corpuscle and 

 was destroying it. Similarly Buffard and Schneider (14), 

 in the case of T. equip erdum, frequently observed the tem- 

 porary fixation or attachment of the parasites by the non- 

 flagellate extremity. On the other hand, Prowazek (1. c.) 

 could find neither endoglobular nor ectoglobular phases of 

 T. lewisi, and considers that the habitat of this parasite is 

 restricted to the plasma. 



With regard to the distribution of the Trypauosomes 

 throughout the body, they are to be met with practically 

 wherever the blood circulates. They are frequently more 

 numerous in the spleen, bone-marrow, kidneys, and liver, 

 than elsewhere^; and Schaudinn finds, in the case of his 

 Avian forms, that it is when passing through the capillaries 

 of these organs (especially of the h^ematopoetic ones), where 

 the circulation is more sluggish, that the parasites usually 

 leave one host-cell, or seek a fresh one. Danilewsky, again, 



' The author does not explain further how this feat is accomplished. 

 Remarkable it certainly is ; for the ectoplasm appears to be a well-defined 

 layer without anything in the nature of a mouth-orifice, and normally, of 

 course, the parasite absorbs food osmotically. 



^ One or two other points in connection with the distribution are more 

 conveniently noticed below, when considering the pathogenic effects caused 

 by the parasites. 



