214 REPORT OF STATE GEOLOGIST. 



ings. Something must give way, and that something is his skin. He 

 casts it aside, however, with but little reluctance, for a new one is 

 ready to take its place, and immediately begins to satiate his appetite 

 once more. Five successive times his skin gets too small for his body 

 and is east aside. Between each of these moults the wings are grow- 

 ing, and when the fifth skin is shed he emerges a mature and full 

 fledged insect. 



However, all locusts do not pass the winter in the egg state. Three 

 or four species hatch in early autumn and the young in various stages 

 can, in suitable localities, be seen jumping vigorously about on any 

 warm sunny day in mid-winter. If their presence at such a season 

 comes to the attention of a newspaper reporter, the press of the fen- 

 tire State is apt to teem with warnings of a coming "grasshopper 

 plague," of which the youngsters are thought to be the advance 

 guard. These hibernating young arc the first to reach maturity the 

 next spring, usually becoming- full grown about the 30th of April. 



A number of species of Acrididas, especially of those belonging to 

 the genus Melanoplus, possess, in the adult stage, only rudimentary 

 tegmina and wings, and resemble immature insects or nymphs in 

 appearance. A close examination will show, however, that these 

 adults have the tegmina in the proper position, while in the immature 

 stages of these and other forms, the tegmina and wings are inverted, 

 being twisted about so that the faces and-margins are just the oppo- 

 site of what they are in the perfect insect. 



About 540 species of Acrididcc are known from the United States. 

 These are divided among four sub-families, all of which are repre- 

 sented in the Indiana fauna, 63 species having been taken in this 

 State. These sub-families may be separated by the following table: 



A SYNOPSIS OF THE SUB-FAiULIES OF ACRIDID.E KXOWX TO OOCUR IX 



IXDIAXA. 



. Size, very small; pronotum extending to or beyond the end of ab- 

 domen; tegmina represented by small scales oi* lobes on the sides 

 of the body; claws of tarsi without a pad or cushion between 



them Te TTiGiN.E. p. 215 



. Size, larger; pronotum never extending over the abdomen; tegmina 

 usually well developed, but sometimes abbreviated or even want- 

 ing; claws of tarsi furnished with a small cushion or pad between 

 them. 



6. No spine or tubercle on the presternum between the front pair 

 of legs. 



c. Face or front head very obliqne. usually meeting the ver- 

 tex at an acute angle; the fastigium horizontal or a little 



