CHAPTER XIX 



TRYPANOSOMID^ 



Preliminary remarks — Trypanosomidae — Herpetomoninae — Trypanosominae— ^ 

 Incertae sedis — Leucocytozoon — Spirochaetacea — References. 



PRELIMINARY REMARKS. 



In this chapter we complete the study of the Monozoa by considering 

 the forms allied to Herpetomonas and to Trypanosoma, which 

 have been gathered together into one family, the Trypanosomidae 

 of Doflein, and follow this by a description of Leucocytozoon and 

 the Spirochaetes, of which the classification is uncertain. 



FAMILY TRYPANOSOMID^ Doflein, 1901. 



Definition. — Monozoa possessing one fiagellum, without a collar 

 and with the kinetonucleus separate from the nucleus . 



Classification.— This family may conveniently be divided into 

 two subfamilies as follows : — 



{a) Undulating membrane absent or rudimentary and the kine- 

 tonucleus on the flagellar side of the trophonucleus- — 

 Subfamily i, Herpetomonince Castellani and Chalmers, 

 1919. 



(h) Undulating membrane well developed and the kineto- 

 nucleus on the afiagellar side of the trophonucleus- — 

 Subfamily 2, Trypanosomince Castellani and Chalmers, 

 1919. 



SUBFAMILY HERPETOMONIN^ Castellani and Chalmers, 



1919. 



Definition.— Trypanosomidae in which the undulating membrane 

 is either rudimentary or absent, and in which the kinetonucleus is 

 situate on the flagellar side of the trophonucleus and remains there. 



Type Germs.— Herpetomonas Saville Kent, 1881. 



Classification. — ^The various genera which used to be gathered 

 together in the family Herpetominidse were— 



1. Herpetomonas Kent, 1881. 



2. Leptomonas Kent, 1881. 



3. Crithidia Leger 1902, emendavit Patton, 1908. 



4. Leishmania R. Ross, 1903. 



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