242 



H. M. WOODCOCK. 



Section IX. Comparative Account or the Life-cycle. 



(a) Life-history of Trypanosoma ziemanni com- 

 pared with that of Trypanomorpha. 



Besides demonstrating a complex life-cycle in the case of 

 Trypanomorpha^ Schaudinn has shown that another para- 

 site of Athene noctua, Trypanosoma ziemanni, also 

 has a similar history, and undergoes much of its development 



Fig. 30. — Growth and nietamorpliosis of an indifferent ookinete 

 of Trypanosoma ziemanni. (After Schandinn.) 



in the same Invertebrate host, Culex pipiens. While 

 agreeing in its main features with that of the first-named 

 parasite, the life-cycle of this form presents certain important 

 differences, which may now be considered.* 



The most remarkahle modification, and one wliicli hears forcibly npon the 

 relationship of the Ilajmosporidia to this group, occurs almost .at the com- 

 mencement of tlie life-history. Instead of passing at once into the Try- 

 panosome stage, all three types of ookinete first enter upon a period of 



' For the general account of the life-history the reader is referred to 

 the description of Trypanomorpha, and to the tabulated summajy of 

 the principal stages given on p. 180. 



