this matter from any standpoint. This is a very valuable paper. 

 Discussions will be limited to five minutes. 



Mr. LeK^ — I would like tO' ask through you, Mr. Chairman, 

 whether Mr. Brooks is of the opinion that this circulatory sys- 

 tem that he has suggested wiould be necessary in the meadows 

 of counties other than Essex. 



PiiESiDENT Darnai,!^ — Any further questions or discussion? 



Dr. He:adi,kk — Mr. Chairman, if I miay I would like to add 

 a word to this paper. I believe that it represents a discussion oi 

 perhaps the next step in properly handling the diked salt marsh. 

 We unquestionably have had breeding in the ditches in our diked 

 salt marshes, and the problem is how to prevent it. It has been 

 the theory of a number of us that the establishment of the cir- 

 culatory system on these marshes would take care of the breed- 

 ing. Mr. Brooks has tried to show how such a system might be 

 put in. 



There is another way in which this problemi is met in Hudson 

 County. A centrifugal pump pulls the water out of the ditches 

 at such a rate that any mosquitoes that happen to be breeding in 

 it are carried with it and thrown by the pumps over into the 

 main drains. 



The diking of a salt marsh to control mosquito breeding is 

 limited in application. The cost is prohibitive. The demiands 

 of the population do not make it necessary. I believe that the 

 diking method of controlling mosquito breeding is going, for a 

 number of years at least, to be limited to those areas which are 

 especially difficult to handle, and to those areas which lie near 

 great populations. Other parts of the marsh must be cared for 

 by a series of ditches which open all parts of the marsh tO' the 

 penetration by killifish and the consumption of the wrigglers 

 by these fish. In other words, the great part oi the marsh is 

 going tO' be kept free fromi breeding, or reasonably free fromi 

 breeding, by turning one natural force against another. The 

 natural force that we wish tO' eliminate is the mosquito. The 

 natural force that we use to eliminate that is the killifish. 



2 MO 



