lyS TETTIGID.E OF NORTH AMERICA 



which may live for a time and enter the micropile of the succession of ten 

 to fifteen eggs that may afterwards develop. The transmission of many 

 lines of descent to the same brood through the male have an important 

 bearing on the causes of variation. 



A 15ROOD OF TWENTY-FOUR TETTIGIDEA PARVIPENNIS 

 HATCHES, PIGMENTATION ACQUIRED IN FIFTY MINUTES. 



A brood of twenty-four Tettigidea parvipennis came out of the 

 ground at twenty minutes of four o'clock p. m., leaving all the little folded 

 amnions near the hole where they emerged. The Tettigidea larva is 

 much larger than Tettix, and at once recognizable. The adult parents 

 were placed in the jar May 23, and were from Windsor Park, 111. Within 

 three minutes the larvaj were all out of the burrow; in less than an hour 

 (fifty minutes) they began to take on a clouded appearance of sufficient 

 depth of pigmentation to easily escape detection. June 13, 1897. 



TETTIGIDEA PARVIPENNIS, EIGHTEEN DAYS' INCUBATION. 



Some eggs laid by Tettigidea parvipennis on June 28, hatched July 15 

 (igoi), or in eighteen days. Seventeen eggs were laid in this mass. 



PERSISTENCE OF THE SEXES REMAINING TOGETHER 

 DURING CONJUGATION. 



For three days the male of Tettigidea parvipennis has, with only 

 short intervals of a few hours, kept on the female's back, copulation being 

 almost constant. June 15, 1898. 



TETTIGIDEA PARVIPENNIS OVIPOSITING, THE MALE SEEK- 

 ING THE FEMALE AFTEKWARDS-TWELVE EGGS LAID. 



At 3:40 p. m. Tettigidea parvipennis started to oviposit between the 

 stalks of grass, but seemed dissatisfied, and made no further effort to lay 

 her eggs until 5:30 p. m., when she selected a lichen-covered spot. In the 

 operation of ovipositing she continued as late as nine o'clock p. m., and 

 when I last saw her at night she still had her abdomen buried in the ground. 

 The following morning on looking in the jar I found her in copulation with 

 the male. The eggs were laid five millimeters below the surface, and the 

 egg-mass contained twelve eggs. June 22, 1898. 



TIME OF INCUBATION IN TETTIGIDEA PARMPENNIS, 

 EIGHTEEN DAYS. 



At 1:30 p.m. si.\ eggs which I had left in vivarium hatched. The young 

 larvie are distinctly larger than Tettix. The parents of these eggs, Tetti- 

 gidea parvipennis, were introduced into the jar June 3, and on the 5th, the 

 female oviposited, making the time of incubation eighteen days. The 

 weather has been favorable to hatching. June 23, 1898. 



