Cockroaches, Locusts, Grasshoppers, and Crickets 161 
much reduced, being nearly lost, and as this cricket crawls rather than 
leaps, the hind or leaping legs are not so disproportionately larger than the 
others as in the above-ground crickets. The males make a sharp chirping 
loud enough to be heard several rods away. The common species, called 
the northern mole-cricket, Gryllotalpa borealis , has the wing-covers less than 
half the length of the abdomen, while the wings extend 
only about one-sixth of an inch beyond them. A less 
common species, G. Columbia , the long-winged mole- 
cricket, has the hind wings extending beyond the 
tip of the abdomen. The mole-crickets like rather 
damp places near ponds or streams, where they make 
channels with raised ridges which resemble miniature 
mole-hills. These “runs” usually end beneath a stone 
or small stick. The insects are infrequently seen, as 
they remain mostly underground, only occasionally 
coming out at night. The female deposits from two 
hundred to three hundred eggs in masses of from 
forty to sixty in underground chambers, and the young 
are about three years in reaching maturity. When 
present in any region in large numbers mole-crickets Fig. 230.—The Porto 
become seriously destructive because of their attacks 
on plant-roots. In Porto Rico a mole-cricket, Scap- lus. (After Barrett; 
teriscus didactylus (Fig. 230), called “changa,” dam- natural size.) 
ages tobacco, sugar-cane, and small crops to the value of more than 
$100,000 annually and is by far the most serious insect 
pest in the island. 
Much smaller than the true mole-crickets are the 
pygmy, burrowing crickets of the genus Tridactylus, 
of which several species occur in the United States. 
The largest species, T. apicalis (Fig. 231), is about 
^ inch long. They resemble the mole-crickets in general 
body characters, but are more brightly colored, and the 
fore feet, although broad and flat for digging, differ in 
being curiously armed at the end with three spurs; hence 
Fig. 231. Tndactylus the generic name. They can leap amazingly, so that 
apicalis. (After & . . / r • i 
Lugger; natural size they seem, on jumping, to disappear most mysteriously, 
indicated by line.) the eye not being able to follow them in the air. 
The most aberrant of all the crickets are the tiny flat and broad-bodied 
species of the genus Myrmecophila, which live as commensals or mess¬ 
mates in the nests of ants. They are found only in ants’ nests, have no 
compound eyes, and the hind femora are much swollen and enlarged. 
