312 Herpetomonas [Leishmania] Donovani 
June 30th Col. Robertson punctured the spleen of another case of Kala 
Azar and I obtained 6 c.c. of blood rich in parasites ; Dogs A and B 
were each inoculated intra-peritoneally with 3 c.c. of this blood. 
Dog B was killed on August 4th, when it weighed 514 grams. The 
following are the post mortem findings: 
Spleen. Weight 12^ grams, it appeared quite healthy; eight 
smears were made from different parts of the pulp and stained with 
Giemsa’s stain. I was unable to find any parasites in them. 
Liver. Weight 118 grams, there were no macroscopic appearances 
to be noted; eight smears were made from different situations, and 
were stained with Giemsa’s stain. No parasites could be found. 
The kidneys, lungs, intestines and peritoneum were quite healthy, 
and no parasites could be found in the bone marrow. 
Dog A was killed on August 11th, when it weighed 1272 grams. 
Spleen. Weight 26 grams, no macroscopic changes; 12 smears were 
made as above, but no parasites were found. 
Liver. Weight 255 grams, healthy; eight smears were made, but 
they contained no parasites. 
All the other organs were healthy. 
Dog C is at present in the Institute at Madras. 
From these experiments it would therefore appear that the dog is 
not susceptible to Herpetomonas donovani. The few dogs I have had 
the opportunity of examining in Madras have never harboured this 
parasite, and Christophers, who has had a much larger experience with 
these animals, does not record its occurrence. 
Should it eventually prove to be the case that no animals are 
susceptible to the parasite of Kala Azar, it would further support the 
view that the Indian and Assam species is distinct from the Tunisian 
organism. I have been unable to collect any evidence in Madras that 
would support the view that dogs play any part in the transmission of 
Kala Azar. In Madras it is essentially a house disease and few of the 
people in Georgetown, where it is very prevalent, keep dogs. 
The Genus Herpetomonas 1 . 
Believing as I do that the parasite of Kala Azar and its two allies 
belong to the genus Herpetomonas, I have for the last two years made 
a special study of this genus. These flagellates are parasitic in the 
1 This portion of the paper should be read in conjunction with my description of 
Herpetomonas lygaei in the Archiv fur Protistenkunde, Yol. xm. p. 1, 1908. 
