ORTHOPTERA 



251 



what like a hand or a foot of a mole ; they are terminated by strong 



blade-like teeth, termed the dactyls (Fig. 274). 



Two of the tarsal segments are blade-like and so situated that 



they can be moved across the dactyls like the 



cutting blades of a mowing machine (Fig. 275). 



Sharpe ('95) states that this organ enables the 



mole-cricket to cut the small roots it meets in 



digging its burrows ; but this is doubted by Morse 



('20), who believes that the roots are cut by the 



powerful mandibles. 



The antennse of mole-crickets are much shorter 



than the body; the hind femora are but little 



enlarged, not well fitted for jumping; and the 



ovipositor is not visible externally. The name of 



the type genus, Gryllotalpa, is from Grylhis, a 



cricket, and talpa, a mole. 



Two genera of mole-crickets are found in the 



United States: Gryllotalpa, in which the front 



tibias are furnished with four dactyls; and Scap- 



tenscus, in which each fore tibia bears only two 



dactyls. Each of these genera is represented in 



our fauna by several species. 



Our best-known and most widely distributed 



species is Gryllotalpa hexaddctyla (Fig. 274). This 



species has been generally known in this country as Gryllotalpa 



horedlis; but this name is now be- 

 lieved to be a synonym. The 

 range of this species extends from 

 British America to the southern 

 part of South America. The 

 length of the body is 20-30 mm. 

 The mole-crickets are not 

 common insects in this country; 

 but occasionally they are found 

 in great numbers in a limited lo- 

 cality. They make burrows in 

 moist places from six to eight 

 inches below the surface of the 

 ground, and feed upon the tender 

 roots of various plants, and also 

 on other insects. The eggs are 

 deposited in a neatly constructed 

 subterranean chamber, about the 

 size of a hen's eee. 



Fig. 274. — Gryllotal- 

 pa hexadactyla. 



Fig. 275. — Front leg of a mole-cricket; 

 A, inner aspect; B, outer aspect; e, 

 ear-slit. (Prom Sharp.) 



Subfamily TRIDACTYLIN^ 



The Pigmy Mole-Crickets 



The members of this subfamily resemble the mole-crickets in the 

 form of the body and in their burrowing habits; but they are much 



