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the autumn, and this is precisely the season in which Phlehotomus 

 abounds. The Arabs call the disease the date boil, indicating the 

 coincidence of its prevalence with the ripening of the dates in 

 September. The lesions are almost always on exposed parts of the 

 body and a considerable number may occur on one individual ; both 

 these facts are consistent with the attacks of a winged insect and 

 especially of Phlebotomus. The authors raise an objection to their own 

 theory, namely, that in Algeria the disease is only known in Biskra, 

 whereas Phlebotomus swarm all over the North of Africa and have 

 been sTjecially studied in places where the malady was thought to be 

 quite unknown. It is now believed to be far more widespread than 

 was supposed, and a list of widely separated places is given, in which 

 Oriental sore is known to exist. In order to explain why all areas 

 w^here Phlebotomus occurs are not infected with oriental sore, two 

 hypotheses are put forward, (1) the existence in certain places only 

 of a reservoir of Leishmania tropica and (2) the aptitude of 

 certain species only of Phlebotomus to transmit the disease. Man 

 himself cannot be considered the reservoir, nor, in spite of Gonder's 

 researches, can the disease be considered as one of the general system. 

 The number of organisms circulating in the peripheral blood is hardly 

 sufficient to infect biting insects and these never settle on, or feed 

 upon, the sores; even other flies can hardly be regarded as carriers, 

 because the exudations from the sores contain but very few Leishmania 

 bodies and no biting insects would attack the hard crust at the edges 

 of the sore Avhere these bodies are very numerous. The reservoir must 

 therefore be sought amongst animals capable of being bitten by 

 Phlebotomus. Lutz and Nelva have remarked that horses in desert 

 places in Brazil are more frequently bitten than their riders ; Roubaud 

 found P. minutus var. africanus living in swarms in company with a 

 lizard, Agama colonomm, biting it without apparently causing gi-eat 

 annoyance ; Howlett has recorded the gecko as the natural host of 

 P. mmutus [see this Review, Ser. B, i, p. 211]. According to Townsend, 

 in South America Phlebotomus will bite almost any warm-blooded 

 animal, as well as reptiles ; Schannon and Bartsch have seen P. vexator 

 biting snakes in Maryland and Virginia ; and Roubaud has lately noted 

 P. minutus var. africanus attacking a captive python in Senegal, and. 

 he regards these insects as specially attacking reptiles. P. -jxipatasii 

 and its congeners, on the other hand, specially affect man, and 

 P. minutus also attacks the Algerian gecko, Tarantola mauritanica. 

 Howlett has shown that the distribution of P. minutus coincides with 

 that of the geckos, and it may be further said that the distribution of 

 Oriental sore is the same. The Algerian gecko is common in all the 

 houses in Biskra and three species of Phlebotomus are found there, viz. : 

 P. papatasii, Scop., P. perniciosus, Newst., and another species which 

 is regarded as identical with P. minutus, Rond., var. africanus, Newst. 

 Cultures of the organs of the gecko have yielded bodies closely resembling, 

 if not identical with, the leptomonads of Oriental sore. At Beni-ounif- 

 de-Figuig, where the disease is unknown, Phlebotomus is very abundant, 

 but of 203 insects captured, 202 proved to be P. pajMtasii and only 

 one P. minutus var. africanus; six geckos examined yielded lepto- 

 monads resembling those found in the geckos of Biskra. Other 

 comparative studies have been set on foot at various places and will 

 be continued when circumstances permit. 



