﻿388 The Philippine Journal of Science w" 



tian malarial parasites. He was furthermore able to transmit 

 the disease by allowing the experimentally infected mosquito to 

 bite a healthy man who had volunteered to submit to the experi- 

 ment. Banks now considers the Myzomyia ludloivii with which 

 he experimented to be identical with Anopheles (Myzomyia) 

 7'ossii. 



In 1910 De Vogel infected and secured development of the 

 malarial parasites up to the oocyst stage in mosquitoes bred 

 from the larvse collected at Samarang, Java. He failed to follow 

 the development of the parasites in the mosquitoes further 

 because of the difficulties in keeping the mosquitoes alive suf- 

 ficiently long in captivity. Infections were obtained with indi- 

 viduals bred from larvae collected from brackish or salt water 

 and not with individuals of the same species bred from the larvse 

 obtained from fresh water. De Vogel first identified the mos- 

 quitoes breeding in brackish or salt water as Anopheles vagus 

 Donitz, which is considered by some as a synonym of Anopheles 

 rossii Giles. Specimens were submitted to Professor De Meyero 

 of Amsterdam, and he declared them to be Myzomyia rossii. 

 Individuals hatched from the same lot of larvse as those infected 

 were submitted to Theobald, who likewise pronounced them to 

 be Myzomyia rossii. 



Strong (1910), in the discussion of De Vogel's paper at the 

 first biennial congress of the Far Eastern Association of Trop- 

 ical Medicine held at Manila in 1910, made the following 

 statement with reference to the transmission of malaria by 

 Anopheles ludloivii or rossii in the Philippine Islands : 



During the past year in connection with the work in the courses of trop- 

 ical medicine in the Philippine Medical School relating to the study of 

 malaria, we attempted to infect numerous specimens of Myzomyia rossii by 

 exposing patients suffering with severe cases of aestivo-autumnal and tertian 

 malaria to their bites. However, although these experiments were extensive 

 and were carried on over a period of several months during the autumn, 

 they were entirely unsuccessful. In no case did the dissection of any of 

 these mosquitoes, although a large number were examined, reveal any 

 oocysts in the walls of the stomach, and in the study of stained sections made 

 of the salivary glands no sporozoites could be detected. Later attempts to 

 infect other human beings by the bites of specimens of Myzomyia rossii, 

 which had been previously fed on the blood of patients suffering with severe 

 malaria and whose blood certainly contained gametes, also failed. The 

 larvffi of these mosquitoes were collected in the estuaries about the city. 



Strong states that it is now known that Myzomyia ludlowii 

 and M. rossii are one and the same species. 



Christophers (1912) found Anopheles (Nyssomyzomyia) lud- 

 lowii, a species which breeds in and about salt swamps and which 

 is not found at a greater distance than a kilometer and a half 



