-li- 

 on an insect which is not an essential link in the chain of 

 infection. (Shortt et al_., 1930, p. 929) 



It appears that this final report was written before all the results 

 were in, for on February 19, 1931, the following telegram from New 

 Delhi was received by Nature magazine: "Lieut-Col. Shortt reports 

 successful transmission of Leishmania donovani to Chinese hamsters by 

 bites of artificially infected Phlebotomus argentipes . Hamster bitten 

 repeatedly during twelve months; generalized infection found seventeen 

 months after experiment began" (Shortt, 1931, p. 308). Their 

 persistence had paid off. 



The kala-azar commission continued its efforts to transmit kala- 

 azar to man by bite of P. argentipes but met with uniformly negative 

 results (Swaminath et aj_., 1942). It was only after Smith et al. 

 (1940) devised the technique of keeping the flies alive after 

 oviposition by feeding on the juice of boiled raisins that Swaminath 

 et aj_. (1942), using this technique, were able to forge the final link 

 of evidence incriminating P. argentipes as the insect vector of kala- 

 azar in India. They suggested that feeding the flies on fruit juices 

 acted either by increasing the virulence of the parasites or 

 increasing the parasitemia, thus enabling them to reach the anterior 

 part of the midgut (cardia) more rapidly. 



Leishmania donovani infantum (infantile visceral leishmaniasis). 

 The coincidental distributions of visceral leishmaniasis and the sand 

 fly P. chinensis Newstead in China north of the Yangtze River, pointed 

 to this insect as the vector of the disease. Young and Hertig (1926), 

 in North China, dissected hundreds of field-caught P. chinensis , P_. 

 sergenti , and P_. perturbans de Meijere and examined them for the presence 

 of flagellates; all specimens were negative. They also attempted to 



