200 



BIOLOGY FOR BEGINNERS 



greater need of one controlling region, so that all the body's nu- 

 merous functions could operate in harmony and as a result the 

 need of a brain developed. Its location, as explained above, was 

 almost of necessity in the " head " or anterior end of the animal. 



FIG. 64. Developing stages, after hatching, of a locust, Mdanoplus femur- 

 rubrum, a, just hatched, without wing-pads; 6, after first moulting; c, after 

 second moulting, showing beginning wing-pads; d, after third moulting; e, 

 after fourth moulting; /, adult with fully developed wings. (After Emerton; 

 younger stages enlarged; adult stage, natural size. From Kellogg.) 



Life History. The eggs are fertilized internally, and are deposited 

 in two masses, protected by a gum-like substance, in holes which 

 the female digs in the earth with her ovipositor. From twenty to 

 thirty eggs are thus deposited in the fall, and hatch the following 

 spring. This illustrates a twofold advantage of egg reproduction, 

 for, not only is the number of individuals increased, but they pass 



