182 



NATURAL HISTORY OF ARTHROPODS. 



several occur in Europe and in the United States. The tree-crickets are brightly colored, 

 and resemble at first glance some of the smaller Locustidse which live among trees. 

 They all lay their eggs above ground, either upon the plants on which they most fre- 

 quently occur, or upon some other plant in close proximity. The mode of egg-laying 

 differs greatly in the various genera, and sometimes among the species of a single genus. 

 The Snowy Tree-Cricket ( (Ecanthus niceus) is of a delicate greenish, semi-trans- 

 parent white, though some specimens have a blackish shade. This cricket, although 

 known to devour plant-lice, and likewise the eggs of some moths, 

 is injurious to vegetation, gnawing the stems of grapes so as to 

 cause them to fall, and puncturing, for purposes of oviposition, the 

 twigs of various plants. Among plants chosen are the vine, rasp- 

 berry, blackberry, peach, white willow, and soft maple. In deposit- 

 ing she makes a straight, longitudinal, contiguous row of punctures, 

 each puncture about the size of that which would be made by an 

 ordinary pin. From each of these holes a yellowish elongate egg 

 FIG. 256. (Ecanthus runs slantingly across the pith, as shown in the accompanying 



nii'eus, tree-cricket. ' J 



illustration. The twigs or canes thus punctured almost invari- 

 ably die above the punctured part. The chirp of this species is intermittent, re- 

 sembling a shrill " te-reat, te-reat, te-reat," with a slight pause between each. 



The Broad-winged Tree-Cricket ((Ecanthus tatijjcn/iis) is 

 much like the preceding, but larger, and the female lays her eggs 

 chiefly in grape-canes, drilling a single hole at intervals of about 

 one-third of an inch. The jaws are first used to slightly tear 

 the outer bark. With the antennas stretched straight forward, 

 and the abdomen bent up so as to bring the ovipositor at right 

 angles with the cane, she then commences drilling, working the 

 abdomen convulsively up and down about twice each second. 

 The eggs are laid lengthwise in the pith, but always in two sets, 

 one each side of the hole. The number varies according to the 

 size of the cane, and the distance between the holes is also 

 variable. The hole is usually filled up with a white mucous secre- 

 tion, though there is very little of it about the eggs. This secre- 

 tion also doubtless serves to facilitate the drilling. The same 

 female will lay over two hundred eggs, and will sometimes 

 puncture the same cane at intervals of one-third inch for one 

 and a half feet or more. 



The shrill cry of latipennis is continuous and recalls the 

 trilling of a high-pitched dog-whistle in the distance. The key 

 varies, however, and is sometimes much less high and more 

 musical than at others. The commingled shrills of this species 

 recall also the distant croaking of frogs in spring. The broad 

 wings are thoroughly elevated during the act, or even bent for- 

 ward, and the vibration is so rapid that there appears to be no 

 motion. 



Orocharfs saltator, which is found throughout the warmer parts of the middle and 

 eastern United States, is of a pale yellowish-brown color. The female differs from the 

 male in possessing a long ovipositor and in having the wings more rounded and less 

 ribbed and veined. She lays her eggs in the corky, rough bark of the trunk and older 



FIG. 257. a b, Stem of 

 blackberry with eggs of 

 (Ecanthus niveus ; c, egg 

 enlarged ; (/, ornamen- 

 tation of egg. 



