LEISHMANIA DONOVANI 415 



inoculated twelve dogs either intravenously or intrahepatically. Five of these 

 became infected. Two others were infected by inoculation with both cultures and 

 spleen material from a heavily infected monkey. The conrse of the disease resembled 

 that produced by the Mediterranean virus. In two cases keratitis was observed. 



Xicolle (1909) succeeded in infecting monkeys {Macacus sinicus and M. cyno- 

 molgus) with the Mediterranean virus in Tunis, while Laveran (1917), with the same 

 virus, inoculated fourteen monkeys {31. sinicus, M. cynomolgus, and M. rhesus), 

 of which two acquired a fatal infection, seven only a slight one, while five did not 

 become infected. Marshall (1911), working in the Sudan, succeeded with five 

 monkeys {Cereopithicus sabceus) out of seven inoculated with the Sudan virus. 

 Archibald (1914) also infected a monkey of the same species. Monkeys infected may 

 die in a couple of months, or the disease in them may run a chronic course terminating 

 in recovery. The infection shows the same irregularities as in the dog. With the 

 Indian virus. Row (1912) produced a general infection in M. sinicus and 31. cyno- 

 molgus. Of especial interest are the results obtained by this observer after local 

 inoculation of the skin. A 31. sinicus was inoculated with material from the spleen 

 of a case of kala azar by scarification of the skin, and another by subcutaneous 

 injection of a culture. In both cases local nodules appeared at the sites of inocula- 

 tion several months later. Leishmania were present in these nodules, one of which 

 was excised and used for further inoculations. With the material thus obtained 

 another monkey was inoculated in the skin, with the production of a local infection, 

 while two mice and a monkey injected intraperitoneally acquired a general infection. 

 Exjjeriments of a similar kind were carried out by Korke (1914). He noted, how- 

 ever, that subcutaneous inoculation sometimes gave rise to a local skin lesion, and 

 at others to a generalized infection. In some cases where a local lesion was produced, 

 a generalized infection occurred at the same time. Tyzzer and Walker (1919) 

 produced a purely local lesion by inoculating a monkey cutaneously with cultures of 

 the Mediterranean virus. In this case, there was an incubation period of four 

 mouths. Laveran (1913, 1917), working with the Indian virus, infected monkeys 

 in Paris, and found the course of the infection similar to that produced by the Medi- 

 terranean virus. Shortt ( 1923&) inocu^lated thirteen monkeys with virus from man or 

 other monkeys, and obtained infection in ten. Laveran and Pettit (1909a) were the 

 first to produce an infection in mice with the IMediterranean virus. Successful results 

 were also obtained by Yakimofi and Kohl-Yakimoff (1912) and Rutelli (1914) in 

 Italy. Continuing his experiments, Laveran (1920) noted that the virus could be 

 handed on from mouse to mouse, but that the depreciation in virulence was very 

 marked. He gives the following results of the passage of a strain of L. donovani 

 of canine origin through mice: 



Numher of 

 Mice Infected. 



1st inoculation . . . . 17 



2nd ,, . . . . 13 



3rd ,, .. .. 16 



4th ,, . . . . 19 



5th ,, .. .. 14 



6th ,, .. .. 6 



It th\is appears that with successive passages through mice, though infection usually 

 takes place, the percentage of natural recoveries increases. The infected mice 

 became anaemic, showed marked enlargement of the spleen, and degeneration of the 

 testicle. Mice examined over a year after inoculation were in some cases still 

 infected, while in others, though no parasites could be found, the characteristic 

 lesions were still present. 



