ECONOMIC IMPORTANCE OF MOSQUITOES 329 



It is fair, therefore, to consider the mosquitoes of great economic 

 importance, and as serious drawbacks to any community from three 

 points of view : 



First, their influence, direct and indirect, upon the health and well- 

 being of the inhabitants. 



Second, their influence upon the development of the agricultural 

 resources, preventing or limiting the profitable use of infested territory 

 for certain purposes. 



Third, their influence upon land values due to the drawbacks men- 

 tioned under 1 and 2. 



Having determined these points, it remains to determine whether, 

 in any stage, any species of mosquito is of any value to man, directly 

 or indirectly. The adult is a feeder upon juices of plants and animals ; 

 it produces nothing of use to us and removes nothing that is detri- 

 mental. It is of absolute importance to the continued existence of 

 those microzoa that pass one stage of their existence in the mosquito 

 body and nowhere else; but no one will argue that it is desirable to 

 continue these organisms, and if the destruction of the mosquito is 

 accompanied by the elimination of Plasmodia, Trypanosomes; Filaria 

 and others of similar ills, a double good will have been accomplished. 



In the larval stages the species are feeders upon the microorgan- 

 isms, animal and vegetable, that occur in more or less stagnant waters. 

 In a way they are scavengers, and it can not be definitely said that they 

 may not destroy or limit some organisms that might otherwise be or 

 become harmful to man. Could it be proved then that these stagnant 

 water areas are necessary, it might be a question whether it is wise to 

 war on mosquitoes until we have a more definite knowledge of the food 

 of the wrigglers. But are these stagnant waters of any use to man, 

 and is it necessary to retain them ? On this point also it seems to me 

 the answer must be against the insects, leaving absolutely no evidence 

 that they are of any use or benefit whatever to the human race, directly 

 or indirectly, as larva or adult. 



The legislature and governor of New Jersey are sufficiently con- 

 vinced of the injurious effects of the mosquito upon the development 

 of the state to venture an investment of $350,000 in the effort to secure 

 the practical elimination of the pest. 



