149 



conclusion, and up to January, 1909, had not been recorded as 

 having been confirmed by experiments ; but it would appear that 

 the embryoes of the parasite pass through the wall of the alimentary 

 canal of the fly and collect in its head, where the larval development 

 is completed within the muscles, and that the adult larva makes its 

 way into the labium of the Stomoxys, and thence into the definitive 

 host. It is interesting to note that numerous dissections of 

 " Hcematobia " (almost certainly Lyperosia), which, according to 

 Noe, are found in swarms on the cattle in the Agro Romano, the 

 collected flies looking from a distance like large black blotches, 

 all proved negative and failed to reveal embryoes of the Filaria, 

 although Noe states that the " Hcematobia " persecute the cattle to 

 a much greater extent than does S. calcitrans. 



II. Trypanosomiases. 



(1) Surra. In Java, according to Schat,* Stomoxys calcitrans, 

 L., and Lyperosia exigua, de Meijere, are the chief agents in the 

 transmission of surra. Writing of the same malady in the Philippine 

 Islands, Musgrave and Cleggf state that it has been " conclusively 

 shown " that Stomoxys calcitrans and certain other biting flies 

 transmit the disease. 



(2) Other Trypanosomiases (in Africa). Some three years 

 ago it was proved experimentally by Dr. G. Bouffard, at Bamako, 

 in the French Sudan, that a species of Stomoxys is capable of 

 transmitting Trypanosoma cazalboui, Laveran, the pathogenic 

 agent in a disease called souma, which causes great mortality among 

 cattle, horses, and donkeys in the French Sudan, but is 

 incommunicable to monkeys, dogs, and rodents. J The experimental 

 transmission was in all probability direct, since a non-infected and 

 an infected calf and forty of the flies were placed in the same stable, 



* Cf. P. Schat, " Verdere Mededeelingen over ' Surra ' " : Mededeel. Proefstation 

 Oost-Java, 3e Ser., No. 44 (1903). 



f Cf. W. E. Musgrave, M.D., and Moses T. Clegg, " Trypanosoma and Trypano- 

 somiasis, with Special Reference to Surra in the Philippine Islands," p. 86 (Manila 

 Bureau of Public Printing, 1903). 



J Cf. G. Bouffard, " Sur 1'Etiologie de la Souma, Trypanosomiase dn Soudan 

 Francais": Comptes Rendus des Seances de la Societe de Biologie, T. LXII. (Seance 

 du 19 Janvier, 1907), p. 71 et seq. (1907). 



