on Mosquito Extcnnination. 35 



City, and of all sections of any city whose Health Department 

 adopts this policy in mosquito work. I feel that even the 

 beginning which we have made here would not have been 

 possible without the public interest and co-operation which 

 we succeeded in arousing. This ought to be the keynote in 

 anti-mosquito enterprises begun by private owners. They must 

 have the co-operation of all citizens if they are to succeed. 

 We do not need any further law about the matter. We should 

 not need the interference of official authority if all private 

 owners were equally public spirited. The strict function of the 

 Health Department, therefore, would seem to be to work, 

 for the general good, upon certain selfish property owners who 

 are not sufficiently careful of the interests of the greatest 

 number to see that their own unoccupied lands are properly 

 drained. Such men should feel the weight of official authority 

 and be made to comply wath the orders of Boards of Health. 

 To all others the Department should be an aid and educational 

 force rather than an instrument merely of menacing authority. 



Respectfully, 



Ernst J. Lederle, President. 



Chairman : We wall now be addressed by Dr. William N. 

 Berkeley, of New York, Author of Works on Mosquitoes. 



THE EXACTNESS OF PROOFS OF TRANSMISSION OF 

 MALARIA BY MOSQUITOES. 



By William N. Berkeley, A.M., M.D. 



Mr. President, Ladies and Gentlemen : 



The relation of mosquitoes to malaria is no longer a hypo- 

 thesis comparable to the famous theories of Newton and Dar- 

 win. It is a demonstration. The evidence is (A) scientific, 

 and (B) practical, and, omitting technicalities, it may be easily 

 summed up in the allotted time. 



(A) Scientific. — Laveran, the French military surgeon, 

 stationed at Algiers during 1880, first noticed in the blood of 

 persons showing the clinical symptoms of ague a peculiar para- 

 site. He published his discovery, calling his parasite the Plas- 

 modium of malaria. Competent observers all over the tern- 



