APPENDIX ON PROTOZOOLOGY 735 



patient's stools, in rabbits infected therefrom and in cultures. The 

 culture medium used was bouillon acidified with about 0*05 per cent, 

 acetic acid and the cultures were maintained at 30 C. 



Trichomonads occur in the digestive tracts, for example, the caeca 

 of rats and mice (fig. 422). In man allied flagellates can occur in 

 similar situations, as well as in other parts of the intestine. 



FIG. 422. Trichomonas from caecum and gut of rat: , nucleus; 

 bl y blepharoplast ; Jl, flagella ; ax, axostyle ; /, undulating membrane ; 

 l>, line of attachment of undulating membrane to the body. X 2,000 

 approx. (Original.) 



Other trichomonad-like organisms have been recently described 

 from the faeces of man, more particularly from cases of chronic 

 dysentery in the tropics. Derrieu and Raynaud 1 (July, 1914), working 

 in Algeria, found a flagellate possessing five free flagella anteriorly 

 and an undulating membrane apparently lateral. They named the 

 parasite Hexamastix ardin-delteili, but the generic name Hexamastix 

 is pre-occupied. Chatterjee 2 (January, 1915), working in India, found 

 probably the same flagellate and called it Pentatrichomonas bengalensis. 



Chilomastix (Tetramitus) mesnili (see p. 57). Alexeieff 3 (1914) 

 now places the parasite originally called Macrostoma mesnili, by 

 Wenyon (1910), in the genus Chilomastix, Alexeieff. The differential 

 characters of the genera Tetramitus and Chilomastix are not especially 

 well marked. According to Alexeieff, Tetramitus is characterized by 

 four unequal flagella (which he figures anteriorly), a ventral cytostome 

 in the form of a linear cleft and a pulsatile vacuole in front of the 

 anterior nucleus. Chilomastix, according to the same author, has 



1 Bull. Soc. Path. Exot., vii, p. 571. 



2 Ind. Med. Gaz., 1, p. 5. 



3 Zool. Anzeiger, xliv, pp. 203, 206 ; and ibid., xxxix, p. 678. 



