212 Annals Entomological Society of America [Vol. X, 



The great problem yet remaining is to free the sea shore and 

 rural communities of southern New Jersey from the mosquito 

 incubus by draining the remaining acreage of salt marsh. 



Until 1912 the sole official agencies at work were the boards 

 of health and the New Jersey State Agricultural Experiment 

 Station, and for various reasons little was accomplished by 

 the former. Since that year the County Mosquito Extermina- 

 tion Commissions and the New Jersey Experiment Station 

 have worked on the problem in close co-operation. 



In 191G, under the able and effective leadership of Dr. 

 Haven Emerson, Commissioner of Public Health of the City 

 of Greater New York, all salt marshes lying within its borders 

 (except those on Staten Island, which were drained some years 

 ago), have been drained or are now in the process of being 

 drained. Under the authority of an act of 1916 a mosquito com- 

 mission was organized in Nassau County, which lies in Long 

 Island just east of the Brooklyn and Queens Division of Greater 

 New York, and the work of draining the salt marshes, which had 

 already been begun on the south side by private subscription, 

 was undertaken in a systematic manner. The amount of work 

 involved in Greater New York and Nassau County is shown 

 by the fact that more than 5,000,000 lineal feet of narrow trench- 

 ing or its equivalent have been cut or contracted for cutting. 

 In addition to this, a certain amount of upland control work 

 has been done, but with its exact nature and extent the writers 

 are not familiar. 



For the purpose of unifying the mosquito control work of 

 the three states concerned, an Inter-State Anti-Mosquito 

 Committee was formed under the leadership of Dr. Emerson. 

 The committee consists of representatives of Connecticut, New 

 York and New Jersey. 



Having laid this basis the writers will now turn attention 

 to some of the striking changes that have been made in response 

 to the practical needs of mosquito control work. 



CHANGES IN SALT MARSH DRAINAGE. 



In 1904 at the close of the preliminary investigations of the 

 problem it was thought to be necessary to drain only the marsh 

 where breeding was found in such a way as to cause the water 

 to flow in and out with the tide and to afford the killifish ingress 

 at all times to all parts of the salt marsh known to breed. In 



