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Schaudinn has described the development of these 
parasites in the stomach of Culex pipiens , where they 
eventually become trypanosomes and finally minute 
spirochaetes. Infection then takes place during biting 
Fig. 76 b. Shewing development of the ookinet of H. ziemanni into 
trypanosomes and then spirochaetes , in the mosquito (after Schaudinn) 
and after again passing through a trypanosome stage 
they infect the blood cells again. This has not been 
confirmed, and it must be borne in mind that owls are 
