458 Report of the Department of Entomology of the 



general descriptions of life stages of tree crickets. 



Egg. — The eggs of the species belonging to the genus (Ecanthus are 

 elongate, cylindrical, and slightly curved. At the time of deposition 

 they are semi-transparent, but later they grow more opaque and 

 become slightly swollen. The cephalic end possesses a whitish 

 opaque cap, which is covered with minute projections, arranged in 

 spiral rows after the fashion of the scales of a pine cone. At the 

 extreme base of the cap, only shallow rhombic depressions occur, 

 but above the first few rows short projections appear between the 

 indentations and gradually increase in size in each successive row. 

 The entire surface of the egg, exclusive of the cap, is etched with 

 what appears to be very minute, cross-hatched scratches. The 

 number and size of the spicules vary considerably with different 

 species and are useful characters for distinguishing the eggs of 

 certain of the crickets. 



Nymph.— First instar (Plate XXVIII, fig. 1) : The newly-hatched 

 tree crickets are pale and delicate creatures, with slender legs and long 

 antennae. After feeding, the size of the abdomen is increased and 

 the contents of the alimentary canal show through the body wall, 

 giving the insects a slightly darker color and more robust appearance. 

 The pronotum, when viewed from above, is rectangular in form, 

 a little wider than long, with sides broadly rounded and margined 

 with a scant fringe of small bristles. The meso- and metanotum are 

 each about equal to the pronotum in width and a little more than 

 half as long. The hind margins of both bear a few small bristles 

 which are directed posteriorly. The cerci are conical, about four 

 times as long as width of base. This stage may be distinguished 

 from the succeeding instar by two characters: (1) The antenna) 

 have thirty-four segments. (2) The sides of the meso- and metano- 

 tum do not project, and extend downward scarcely as far as do the 

 sides of the pronotum. (Fig. 26, a.) 



Second instar (Plate XXIX, fig. 2): This stage differs but little 

 from the preceding instar. The side margins of the pronotum flare 

 outward slightly. The metanotum is a little longer than the 

 mesonotum. Both extend down the sides as far or slightly farther 

 than the pronotum; the side margins are free and lap over the pleura. 

 (Fig. 26, b.) The number of antennal segments is about double that 

 of the preceding stage. The females show the anlage of the ovipositor 



