188 



ELEMENTAEY STUDIES IN INSECT LIFE 



morphosis. After the first molt she loses her legs, 

 antennae, and eyes, and remains stationary as a footless 



FIG. 157. Adult female scale insect (Kerm.es pubescens) living on oak twig. An 

 unprotected scale. Enlarged. Photographed from nature. 



grub upon the host, there to draw sustenance and re- 

 produce her kind. Some female forms of these insects, 

 however, retain the power of locomotion. Many of 



FIG. 158. Protected scale in- 

 sects. Scales under which fe- 

 male scale insects (Diaspis 

 snowii) live. These scales are 

 formed from a waxy substance 

 which is an excretion from the 

 back of the scale insect's body. 

 The scale does not adhere to 

 the insect's back. 



FIG. 159. Protected 

 scale insect. Scales 

 which cover the male 

 scale (Diaspis Snowii) 

 during its metamorpho- 

 sis. 



these footless females are well 

 protected by an outer scale 

 (Fig. 158), which is formed by 

 an excretion from the dorsal part 

 of the body. Others are naked. (Fig. 157.) To the 

 former kind belong the noted and injurious scale com- 

 monly known as the San Jose scale. 



