THE GENERA HERPETOMONAS AND CRITHIDIA 243 



Neither conjugation nor mode of infection has been observed 

 in connection with these parasites, and the caution which Novy, 

 MacNeal, and Torrey express in regard to the possible confusion of 

 such flagellates of insects, with developmental stages of human or 

 other vertebrate blood parasites, is certainly well grounded, but we 

 cannot indorse their view that all such parasites are to be looked 

 upon as developmental stages in the life history of trypanosomes. 



