22 AGRICULTURAL EXPERIMENT STATION. 



terminal gills or paddles. If we examine the thickened or 

 hunched up end we find ourselves able to trace the outlines of 

 the future adult all covered by the pupal shell and glued together 

 closely. 



We make out a black spot where the future eye will be found, 

 and curving above and behind it we see the future antenna, the 

 joints already indicated. The wing-pads, forming the largest 

 part of the enlargement, are plainly to be recognized, and, folded 

 up ag'ainst them so closely as to almost defy separate recognition, 

 are the cases for the long, jointed legs. 



rumloets 

 lorGatliino tube 



SUJimmm 

 loaddles 



Figure 3. 



A mosquito pupa with the parts named. (Original.) 



On the upper surface of the enlarged portion are two breathing 

 tubes, varying in length and form, through which the insect gets 

 its supply of air. Although still an aquatic creature which will 

 die if removed from the water, it is even more dependent upon 

 atmospheric air than the larva, for some larvae have gill struc- 

 tures that enable them to secure oxygen directly from the water. 

 Only in the Corethrincu, which are not really true mosquitoes at 

 all, are the pupse able to^ remain submerged for any length of time. 



It follows that oily coverings on the water surface are quite 

 as effective against the pupa as against the larva. As the pupa 



