MOSQUITOES AND FLEAS. 



11 



This is all Avell enough where the species and the conditions are identi- 

 cal, but when, as is the case with such an insect as that under observa- 

 tion, the principal observations were made upon a different, though 

 congeneric, species, and in another part of the globe, where climatic 

 and other conditions differ, the custom is unfortunate. There is not, in 

 any of our published Avorks, a thoroughly satisfactory figure of a well- 

 determined species of mosquito, or of its earlier stages. The statements 

 quoted in the text-books and manuals date back, in general, to the time 

 of Eeaumur, one hundred and fifty years ago. These observations were 

 made in the month of May, upon a species (Culex pipiens) which does 

 not occur in ^North America, and in the one locality of Paris, France. 

 The notes made upon C.pungens at Washington possess, therefore, some 

 scientific importance. 



Fig. 2.— Culex pungens: Egg-mass above in center; young larva, greatly enlarged, at right; young 

 larvae, not so much enlarged, below; enlarged eggs above at left (original). 



The operation of egg-laying was not observed, but it probably takes 

 place in the very early morning hours. The eggs are laid in the usual 

 boat-shaped mass, just as those of G. pipiens, as described by lveaumur. 

 We say boat-shaped mass, because that is the ordinary expression. A s 

 a matter of fact, however, the egg masses are of all sorts of shapes. 

 The most common one is the pointed ellipse, convex below and concave 

 above, all the eggs perpendicular, in six to thirteen longitudinal rows, 

 with from .'> or 4 to 40 eggs in a row. The number of eggs in each batch 

 varies from liOO to 400. As seen from above, the egg-mass is gray brown ; 

 from below, silvery white, the latter appearance being due to the air 

 film. It seems impossible to wet these egg masses. They may be 

 pushed under water, but bob up, apparently as dry as ever. The egg 

 mass separates rather regularly and the eggs are not stuck together 



