INSECTS: STINGS AND OVIPOSITORS 163 



a pair of scissors near its origin, and then, taking it be- 

 tween the thumb and the finger at the point of section, 

 work it gently to put the files in motion. 



"Besides the muscles necessary for the movement of 

 the files, the handle of each is terminated by a curve 

 of the same hard horny substance as itself, which not only 

 furnishes the muscles with a sort of lever, but serves to 

 press, as with a spring, the two files close to the central 

 piece." 1 



The use of these instruments is the same as I have 

 already alluded to in the case of the saw-flies. The female 

 Treehopper deposits her eggs in holes which she bores 

 in dead twigs by means of these files and lancets. The 

 branches chosen are said to be recognizable by being 

 studded with little oblong elevations, caused by the par- 

 tial raising of a splinter of wood at the orifice of the hole, 

 to which it serves as a cover. These are arranged in a 

 single line, the holes which they protect being only half 

 an inch in length, and reaching to the pith, whose course 

 they then follow. Not more than six or eight eggs are 

 laid in each hole, but an idea of the labors of the indus- 

 trious and provident mother will be formed from the fact 

 that each lays six or seven hundred eggs in the course of 

 the summer. 



1 "Insect Architecture," 149. 



