6 1 6 TR YPANOSOMI ASIS 



Reference may here be made to the views put forward by 

 Schaudinn regarding the relationship of certain spirilla to the 

 trypanosomes. In the athene noctua, besides the Tr. noctuse 

 already referred to, there is a protozoal parasite infesting the 

 leucocytes known as spirillum Ziemanni or leucocytozoon 

 Ziemanni, whose invertebrate host is also the culex pipiens. 

 Ziemann had described the male and female forms in the owl, 

 and microgametes had been observed forming from the micro- 

 gametocytes. Schaudinn observed the formation of an ookinete 

 in the mosquito ; in certain cases this ookinete elongates, and 

 the vermicule rolls itself up into a ball with great proliferation 

 of the nucleus. Each little nucleus attaches to itself a portion 

 of the protoplasm, and, becoming a miniature trypanosome, 

 swarms off and becomes free. These minute trypanosomes 

 elongate and develop into typical spirilla by rolling their ribbon- 

 shaped bodies spirally along their longitudinal axes, the 

 individuals possessing male, female, or indifferent characters, 

 just as in Tr. noctme. These spirilla multiply by longitudinal 

 division, and often after fission the two individuals remain 

 attached to each other by their posterior ends, and in this way 

 there is made possible what is often seen in spirilla, namely, a 

 capacity to move in either direction. The spirilla often divide 

 so frequently that ultimately the individuals become invisible by 

 means of the microscope, and can only be seen when lying in 

 clumps. In this stage Schaudinn thinks the organism would be 

 able to pass through a Chamberland filter, and this may be a 

 very important observation, as throwing light on the etiology of 

 certain diseases, such as yellow fever, in which no visible parasites 

 have been found. 



Schaudinn's views on the trypanosomal characteristics of Sp. Ziemanni 

 raised important questions regarding the morphology of other similar 

 forms which have been long familar, such as Sp. Obermeieri, and 

 also of the Spirochrete pallida which Schaudinn himself discovered. 

 It is as yet too soon to express any opinion on the ultimate effect of 

 these views. According to Schaudinn, a trypanosomal spirillum consists 

 of a central thread which represents the posterior nucleus of the 

 trypanosome ; round this thread the undulating membrane is spirally 

 wound, and the principal nucleus is represented by minute chromatin 

 dots sometimes seen in the course of the spiral. Whether all spirilla 

 have this structure must be left for future investigation to determine. 

 Difficulties arise with regard to the significance of an undulatory 

 membrane as a spirillary characteristic, and also with regard to the 

 terminal flagellum which Schaudinn himself found in Spiroclisete pallida, 

 and which he had previously thought did not occur in protozoal spirilla. 

 It is possible that two groups of organisms have hitherto been classed 

 together under the name spirillum, and that one of these may still 

 have to be placed with the bacteria. 



