

ANATOMY AND PHYSIOLOGY 



it may be inferred that the scales serve to retard the evaporation of mois- 

 ture through the delicate integument of these insects. This inference is 



> V k 

 FIG. 97. Hairs and scales of a moth, Samia cecropia. 



supported by the fact that none of the scaleless Collembola can live long 

 in a dry atmosphere ; they soon shrivel and die even under conditions 



B 



FIG. 98. Development of butterfly scales. FIG. 99. Androconia of butterflies. A, 

 A. Vanessa; B, Anosia. b, basement mem- Pieris rapce; B, Everes comyntas. 



brane; /, formative cell; h, hypodermis; 5, 

 scale. After MAYER. 



of dry ness which the scaled species are able to withstand. In Lepidop- 

 tera the scales are possibly of some value as a mechanical protection; 



