LIBRARY

102 COLLEGE ENTOMOLOGY
most abundant. In the Americas the snowy tree cricket, O. nivelts (De Geer),
a very pale green or yellowish species, the Argentina tree cricket, O. argentinus
Saussure, a pale species, and the black-horned tree cricket, O. nigricornis
Walker, a dark species, are by far the best known species although a number
of others also occur in different localities.
Family GRYLLOTALPIDlE Brunner 1882 (Gryl'lo-talp'i-dre, from the Latin
gryllus, a cricket, + talpa, a mole). Mole Crickets.
These insects are among the most astonishing members of the order. As
the common name implies, they resemble miniature moles because of their
large digging fore tibire and their burrowing habits. It is remarkable that
such large, robust, and sluggish-looking nonsaltatori'al creatures, which tunnel
FIG. 41. The pigmy mole cricket. Ellipes minuta Scudder.
deep into the soil, are also able to fly with alacrity, nearly all species being
winged. The colors are usually brown or black, and the bodies are covered
with short, fine hairs. Auditory and stridulating organs are usually absent
although the latter may be present. The tarsi are two- to three-segmented,
the ovipositor is not protruded, and the unjointed cerci are long or short.
The tegmina are short, and the true wings protrude behind like tails. Although
there are only six genera and 43 species, mole crickets occur throughout the
entire tropical and temperate world. The common mole cricket, Gryllotalpa
gryllotalpa (Linnreus) (G. vulgaris Latreille), which is about 2 in. long, is the
only European species. It has also been introduced into North America. The
African mole cricket, G. africana Beauvois, is the most widely distributed
member and occurs in Africa, Asia, Japan, Philippines, Australia, New Zealand,
and Hawaii. It is a powerful burrower, digging three or four feet into the soil,
and a strong flier. G. coarctata Walker is the common species in Australia; G.
ornata Walker in India; G. unispina Saussure in Turkestan; G. siamensis
Giebel in Straits Settlements, Siam, and China; G. hexadactyla Perty (G. borealis
Burmeister) throughout most of North America, Central America, and South
America; and G. cultiger Uhler in the southwestern parts of the United States.
These insects are often responsible for considerable injury to cultivated crops.
An interesting group belonging to the genus Cylindracheta, including C.
kochi Saussure, in Australia and Patagonia, are slender, elongated, apterous
forms appearing somewhat like embiids which burrow into the stems of plants.
Their tarsi are two-segmented.