12 TETTIGID.^E OF NORTH AMERICA 



end of the abdominal ajjpendages {Tetlix), is thrust away from 

 the body by a rapid kick of the hind tibia. 



In the middle of May (Illinois) the first eggs are laid in 

 the ground, the female accomplishing this act by making a 

 shallow burrow with her ovipositor. The young larvae hatched 

 from this brood mature by fall, passing the following winter 

 in the adult state. The broods hatched in late June and early 

 July are often immature by the time winter arrives, and we 

 find them hibernating in the pupa state. Thus it is that the 

 Tettigidae are about the earliest insects to be found in the 

 Spring, appearing as early as March. The time of incubation 

 varies with the temperature, the early broods of Tcttix hatch- 

 ing in twenty-three days, but as the days become warmer this 

 period is shortened to sixteen days. The number of eggs of 

 Tt'/y/xand Paratcttix vary considerably, but they are more often 

 ten, thirteen, or sixteen in each burrow; in Tettigidca varying 

 from twelve to twenty-six. A departure from the habit com- 

 mon to the larger AcrididjE, is the laying of eggs irregularly 

 together in a pear-shaped mass instead of an egg-pod. (See 

 Plate XI., Figure 2.) In depositing the eggs, they are laid, 

 one by one, side by side, as shown in the accompanying 

 illustration, forming a round mass at the bottom of the bur- 

 row, the attenuated extremities directed upward vertically. 

 A glutenous secretion which is excreted after each egg passes 

 from the vagina holds the eggs together. The burrow is 

 round, rather shallow in Tcttix, deeper in the genus Tettigidea, 

 usually from five to ten millimeters below the surface; 

 and after the eggs are deposited the opening is covered up by 

 particles of earth scraped up with the hind tarsus (Tettix) or 

 the ovipositor {Tcttigidcu). The acutely pointed extremity 

 in the eggs of Tcttix serves admirably for protection. Owing 

 to the shallowness of the burrow the tops of the eggs are quite 

 near the surface, and sometimes exposed, though the female 

 usually endeavors to conceal the eggs with various particles 

 of earth. In certain situations, as when they are deposited 

 in lichens or moss, an insect enemy might easily pass the 

 exposed pointed extremities without molestation. Again 

 the pointed pole of the eggs would be more difficult to destroy 



