ORTHOPTERA. 99 



tain Iccust in the act of ovipositing. Certain species make holes with 

 their ovipositor in a similar manner in fence-rails, logs, stumps, and 

 other masses of wood, in which they deposit their eggs. After the 

 eggs are laid, the entrance to the hole in the wood is closed with a 

 little plug of gummy matter. 



The transformations of three of our more common species of 



' tnoplus have been carefully studied by Riley.* These will & 

 to illustrate the metamorphoses in this family. In each case there 

 are five nymph stages. In the first of these (Fig. 8), although the 



ct would be readily recognized as a young locust, there is a 

 marked difference in the proportions of the body from those pre- 

 sented by the adult. This is especially noticeable in the large size 

 of the head, the relatively stouter thorax and hind femora, and in 

 the short abdomen. From this form to that of the adult ther 

 presented by the other nymph stages a very regular series of grada- 

 tions. The most striking change in the course of the development 

 of these insects is the growth of the organs of flight. In the first 

 nymph stage there is no indication whatever of wings ; in the 

 second stage the caudo-lateral angles of the mesonotum and nieta- 

 notum are very slightly prolonged (Fig. 9). In the third stage these 

 prolongations are more marked, and are easily recognized as rudimen- 

 tary wing-pads (Fig. 10). In the fourth stage a remarkable change 

 has occurred in these organs: up to this point they have projected 

 downward and backward ; they are now turned up so that what 

 their lower edges now meet on the narrow back, and the sid 

 each which was next to the body is now turned outward (Fig. ll). 

 While in this position the second pair of wing-pads is outside of the 

 first the reverse of the relative positions of the full\ 

 wings. In the fifth sta^e the wing-pads are longer, being now about 

 as longasthcpronotum (Fig. 12). Up to this point the development 

 of the wings has been very gradual, the most pronounced ch.i 



organs between the third and fointli 



'} the moult, which occurs at the end of the fifth sta^r. tin ii 



the adult form 13). Tli have now i 



greatly elongated ; they are again re ..that : 



primitive position, with the second pair folded lx n< ath tin first. 



\hich these organs pass. 



So f single i -n of 



I of locust during a year. In the majority of c 



See First Report of the U. S. Ent. Com., Plates I., II , and III. 



