132 
Herpetomonads in Mice 
mice has not shown the parasite in its blood. No symptoms were 
observed in the mice infected. 
This parasite resembles very closely Herfetomonas {Leptonionas) 
Biitschli (S. Kent). The figures given of this organism correspond very 
closely yfith our flagellate, except that in the mouse parasite there is 
not the marked tapering of the non-flagellated end of the body. 
Herpetomonas Butschli, however, inhabits the intestinal tract of Trilohus 
Gracilis, and not a vertebrate circrflatory system.” 
Considering these facts, it appears to us that the following conclusions 
are warranted: 
(1) That natural herpetomonads (or leptomonads) occur in mice. 
(2) That the origin of the infection is to be sought in a flagellate 
of an ectoparasite of the mouse. This flagellate is very probably 
Herpetomonas pattoni, a natural or specific parasite of fleas (especially 
rat fleas), which protozoon can adapt itself to life in the blood of mice. 
(3) Herpetomonads have been recorded from rat fleas, dog fleas 
and human fleas. Probably the flagellates are varieties of one species, 
H. 2 )attoni, which can live in the blood and certain internal organs of 
rats, mice, dogs and man. 
REFERENCES. 
Dutton, J. E., and Toun, J. L. (1903). “FlageHata in the blood of a mouse,” being 
part of Sect, vii of the First Report of the Trypanosomiasis Expedition to 
Senegambia (1902). Liverpool Sch. Trap. Med., Memoir XI, pp. 56, 57. 
Fantham, H. B., and Porter, A. (1914-1915). Some Insect Flagellates introduced 
into Vertebrates. Proc. Garnh. Philos. Soc., xviii, pp. 39-50. 1 Plate. 
Fantham, H. B., and Porter, A. (1915). Fruther Experimental Researches on 
Insect Flagellates introduced into Vertebrates. Proc. Canib. Philos. Soc., 
xvm, pp. 137-148. See also Cambridge Univ. Reporter, xlv, p. 323 (Dec. 1, 
1914) and xlv, p. 931 (May 26, 1915). 
