27 



liavc ii marked inllucnce upon mosquito activity, especially in long- 

 distance flights. Ordinarily these take place with a slow-moving, warm, 

 damp wind, but modifications in direction of flight may be due to 

 mountain ridges and possibly other unknown factors. 



Might, therefore, may seriously interfere with projects for keeping 

 a specified locality free from mosquitos, and })lans and estimates for 

 eradication measures must be based on a study of the mosquito breeding 

 places within a specified area and must include an analysis of mosquitos 

 on the wing throughout that locality for at least one summer season. 

 A thorough knowledge of adult mosquitos will also enable a distinction 

 to be made between local breeding and invasions, and the latter should 

 be traced and the sources eliminated. 



Symposium on Mosquito Control. — Pyoc. Sixth Ann. Meeting, New 

 Jersey Mosquito Extevniination Assoc, Trenton, 1919, pp. 19-55. 

 [Received 2nd December 1920.] 



The records of mosquito work during 1919 in the various counties 

 of New Jersey are almost entirely concerned with the acreage of salt 

 marsh that has been drained in each mosquito-infested locality. In the 

 inland counties, where the salt marsh mosquito problem does not exist, 

 infestation of fresh water occurs in scattered localities, and there is not 

 much attempt at co-operation in dealing with them. 



Headlee (T. J.). Summary of the State and County Work. — Proc. 

 Seventh Ann. Meeting, New Jersey Mosquito Extermination Assoc., 

 Trenton, 1920, pp. 69-75. [Received 2nd December 1920.] 



In summarising the reports of the State and county workers on 

 mosquito problems, the author remarks that during seven years' 

 experience in anti-mosquito measures he has found no more efficient 

 organisation than that now existing in New Jersey. The point of 

 difference from other large organisations is the part played by local 

 units, the working of which is described. Eleven counties are now 

 actively employed in anti-mosquito work, while ten are more or less 

 inactive. The expenses incurred and the work done are briefly reviewed. 

 Inspection or patrol work was carried out over some 320,000 acres 

 of upland and about 115,000 acres of salt-marsh. Oil was used as a 

 supplementary measure, and about 5,000 acres of salt-marsh and a 

 very large acreage of upland marsh were drained. The towns and 

 villages within the protected area suffered very little from mosquito 

 invasion, while man}'- of those outside were heavily infested. In most 

 of the. counties where drainage has been done not a single brood of 

 salt-marsh mosquitos appeared. 



The problem of securing larvicides for future work i s becoming 

 acute, and further experimental work must be done with the object 

 of developing a larvicide to take the place of oil. The constant changing 

 of the relative importance of various species of mosquitos indicates 

 that their biology is not sufficiently understood. It is possible also that 

 an investigation of the agencies attracting the mosquito to man might 

 reveal other methods of attacking the problem. 



Howard (L. O.). Efforts at Mosquito Control in Different Parts of the 



World. — Proc. Seventh .inn. Meeting, Nca.' Jersey Mosquito 

 Extermination Assoc, Trenton, 1920, pp. 16-28. [Received 

 2nd December 1920.] 



The literature that has been published and the chief lines of work in 

 mosquito extermination that have been carried on in all parts of the 

 (1794— B) d2 



