NECESSITY FOR EXACT DATA 185 



daily is this true of Aedes. Many species of this genus develop only in the water 

 formed by melting snows and are to be found only in early spring, while others, 

 are partial to tree-holes or rock-pools. The species of Psorophora breed with 

 astonishing rapidity in the temporary puddles following showers, in which they 

 hatch and pass the four larval stages in a scarcely greater number of days. 



To follow the complete life-history of any species and to breed it from egg to 

 adult will require special experiment in each case. Many species have never been 

 thus bred. In fact, our collectors have all been too much hurried, and in en- 

 deavoring to breed as many isolated examples as possible in a limited time, have 

 been obliged to omit the full and careful study of individual species, so much 

 to be desired. Especially are we lacldng in knowledge of the habits of the adults, 

 their ordinary length of life, dispersal, swarming habits, etc., and these can only 

 be discovered by careful, unhurried observations in the field. 



COLLECTING EGGS. 



Eggs of many mosquitoes may readily be obtained by confining captured 

 females over water. Acdes will generally oviposit readily, but Culex less readily. 

 Bred specimens can not often be mated in captivity, on account of the peculiar 

 swarming habits, which seem essential to copulation, and which can not be 

 executed in a confined space. Doctor Dyar, however, bred two generations cf 

 Aedes atropalpus in a quart jar. Adults confined for oviposition require food. 

 All will eat sugared water, preferably soaked into cotton, or they may be fed with 

 raisins or figs. Many thrive best on mammalian blood. There are, however, few 

 species that absolutely require that article of diet. Speaking broadly, mosqui- 

 toes are fiower-insects, living upon honey. The habit of taking mammalian 

 blood, while common, is not universal, and seems to be obligatory only in the case 

 of a few species. The group in general suffers in reputation from the vicious 

 habits of a minority of its members. We are far, however, from wishing to imply 

 that mosquitoes are negligible or harmless to man ; only we can not emphasize 

 too strongly the need of specific study of the different forms in order to direct 

 our efforts against the dangerous or noxious species only, and not waste time 

 and labor in destroying hannless or even beneficial forms. 



