68 



To-day I received at this hotel a letter from one of the sound- 

 est and sanest physicians in the city of San Antonio, who writes 

 me as follows : 



"It must be said that Dr. Campbell has proven conclusively, 

 first, that the bat is one of the greatest natural enemies of the 

 mosquito, and, second, that malarial disease can be largely con- 

 trolled, if not almost eliminated from the community, by follow- 

 ing bat culture." 



He sends me the minutes of the Bexar County Medical So- 

 ciety of April 30th, 1 9 1 4, endorsing the bat-roost idea as a con- 

 troller of malaria. He sends me copies of affidavits from cer- 

 tain people who live near Mitchell Lake, south of San Antonio, 

 near which the bat roost has been erected, who testify that down 

 to 1910 mosquitoes were very abundant and malaria was rife; 

 that since the erection of a bat roost there have been very few 

 mosquitoes. 



Dr. L. O. Howard, on special request, then made some re- 

 marks on the recent work of the Bureau of Entomology in re- 

 gard to mosquitoes. 



He first called attention to the fact that, of the two most preva- 

 lent mosquitoes of the genus Anopheles occurring in the United 

 States east of the Mississippi River, namely Anopheles quad- 

 rimaculatus and Anppheles punctipennis, only the former had 

 until recently been definitely proved to carry malaria. Former 

 inoculation tests with punctipennis carried on by Doctor Smith 

 and Doctor Berkely in New Jersey, and Doctor Hirshberg in 

 Maryland, had failed; and it was becoming the general opinion 

 that the latter species does not carry the disease. Within the past 

 few months, however, one of the experts in the Bureau of En- 

 tomology, Dr. W. V. King, has shown at New Orleans that this 

 species of Anopheles, everywhere abundant, in that latitude at 

 least, will carry not only tertian malaria but aestivo-autumnal 

 malaria, the latter being the kind of malaria with which the 

 northern experimenters had failed. This .discovery widens the 

 field of necessary anti-mosquito work in all anti-malarial efforts. 

 Lantern slides were shown from the photographs made of 

 microscope slides showing the malarial organism in the stomach 

 and salivary glands of Anopheles punctipennis. 



