New York Agricultural Experiment Station. 469 



the thorax becomes strongly arched upward. (Fig. 32, c.) The young 

 nymph continues to work outward by muscular contractions of the 

 abdomen and by bending the body up and down and from side 

 to side. The unexposed parts are wrapped in a delicate membrane 

 which projects from the hole and clings to the body. The palpi 

 and first two pairs of legs become free first and are then exercised 

 in the air. (Fig. 32, d.) The body begins to straighten out again, 

 pulling the antennae with it. The head turns upward and a watery 

 swelling, formed to fit the end of the egg, then becomes a conspicuous 

 lump on the dorsal side. When the body is far enough out the 

 free legs grasp the wood and assist in relieving the remainder of the 

 body. The nymph holds the antenna? with the mouth parts and 

 gives an upward pull. This is repeated until these appendages are 

 released. (Fig. 32, e.) At about the same time the hind legs and 

 tip of the abdomen become free. The whole process usually requires 

 ten or twelve minutes, but a few of the insects never succeed in com- 

 pletely detaching themselves from the egg. The young cricket on 

 emerging immediately crawls from the eggshell, usually upward on 

 the branch. The watery lump on the top of the head continues to 

 show for twenty minutes after the insect escapes from the egg, but 

 within a short time after this period its disappears. 



In 1909 and 1912 the nymphs began to make their appearance 

 about June 14 and they continued to emerge until about the twentieth 

 day of this month. In 1913 eggs that had been kept in the laboratory 

 for five days commenced to hatch on June 6. 



During the summer of 1913 individuals of this species were col- 

 lected at intervals in the field in order to find out the normal time 

 of appearance of each instar. The record is summarized as follows: 



July 1. First specimen of nymph in second instar. 



" 11. Third instar in maximum numbers; some still in second and a few in 

 the fourth stage. 



" 16. Fourth instar outnumbered third by five to one. 



" 19. First appearance of fifth instar. 



" 23. Fifth instar in minority. 



" 25. Over half of insects in fifth instar, remainder in fourth stage. 



" 29. Adults heard singing at night. 



" 30. An adult which had just transformed collected in the field. 



Aug. 5. Adults and nymphs in about equal numbers. 



In the summer of 1912, which was colder than usual in New York, 

 adults were not taken until August 15, and eight days later were 

 about equal in numbers to the nymphs. On August 27 practically 

 all of the crickets had matured. 



