N. J. Mosquito Extermination Association 53 



THE COI.I.ECTION WEB. 



This plan contemplates the establishment of a web of collect- 

 ing points over the area to be protected. The size of the meshes 

 of this web must depend upon the type of information desired. 

 A very large meshed web will answer for the detection of inva- 

 sions and for the detection of extensive and intensive breeding 

 within the area, but an exceedingly small meshed web will be nec- 

 essary to detect the presence of intensive breeding on very limited 

 areas. The large meshed web is probably the only one which 

 is practicable under present conditions in county-wide work be- 

 cause the number of reliable collectors required would be so large 

 as to carry the expenses beyond the point where the effort would 

 be worth while. In dealing with the problem of protecting a 

 very densely populated area the minute web might justifiably be 

 used. 



SUBSTITUTION OF A MECHANICAL APPARATUS FOR THE HUMAN 



COI.I.ECTOR. 



The two factors in the utilization of a minute web which are 

 most difficult to solve and the one factor in the utilization of a 

 large meshed web which is most difficult to solve are evaluation 

 of the collector on the one hand and the provision of a sufficient 

 number of competent collectors on the other hand. 



With the idea of substituting for the human collector a me- 

 chanical apparatus sufficiently cheap to permit the utilization of 

 large numbers, an investigation of the substances which attract 

 the mosquito to man was undertaken during the latter part of 

 last summer by the Bio-chemist in the Department of Entomol- 

 ogy of the N. J. Experiment Station. Since the mosquito is 

 attracted to and induced to fly across considerable distances it is 

 evident that the attractive force is something which passes 

 through the atmosphere and inasmuch as the heat of the human 

 body would not appreciably increase the temperature at points 

 as distant as those from which the mosquito is attracted to 

 man, it is evident that heat is not the essential attractive agent. 

 The emanations which serve to attract the mosquito- are in all 

 probability odors or something of a similar character. Odors of 

 the human body are the results of its excretions and secretions. 

 The breath, the sweat, the sebaceous secretion, the urine and the 

 feces must one or all be playing a part in these attractive emana- 

 tions. It is a well-known fact that all of these secretory and ex- 

 cretory products in their final decomposition result in the forma- 



