The Shield Bearfrs

Another large group of the katy did family is the subfamily Dectii-inae, mostly cricketlike insects that h^e on the ground, but which have wings so short (Fig. 32) that they are poor musicians. 'hey are called 'shield bearers" because the large back plate of the first body segment is more or less prolonged like a shield over the back. Most of the species live in the western parts of the United States, where the individuals sometimes become so abundant as to form large and very destructive bands. One such species is the Mormon cricket, Anabrus simplex, and another is the Coulee cricket, Peranabrus scabncollis (Fig. 32), of the dry central region of the State of Washington. The females of these species are commonly wingless, but the males have short stubs of front wmgs that retain the stndulati ng organs and enable them to sing wi th a brisk chirp.

Still another large subfamily of the Tettigcnndae is the

Ftc 32. The Coulee cncket, Veranabrus scabricollis, male and female, an example of a cn ;ketlike member of the katydid family

Rhadophorinae, including the insects known as "camel crickets." But these are all wingless, and therefore silent.

The Cricket Family

The chirp of the cricket is prcbably the mcst familiar note of all orthcpteran music. But the only cricket com monly known to the public is the black field crcket, the 'i/ely chirper of our yards and gardens. His European cousm, the house cricket, is famous as the "cricket on the hearth" on account of his fondness for fireside warmth which so stimulates him that he must express his animation m song. This house cricket has been known as Gryllus since the time of the ancient Greeks and Remans, and his name has been made the basis for the name of his family, the Gryllidae, for there are numerous other crickets, some that live in trees, some in shrubbery, some on the ground, and others in the earth

The crio.Kets have long slender antennae like those of the katyd:do, ana also striulating organs on the bases oi the vs mgs, and ears in their front legs. But they differ from the katydids in having only three joints in their feet (Fig. 17 C). The cricket's foot in this respect resembles the foot of the grasshopper (A), but usually differs from that of the grasshopper m having the basal joint smooth or hairy all around or with only one pad on the under surface In most crickets, also, the second joint of the foot is very small

Fig. 33 The wings of a tree cricket

A, right front wing of an immature female, show.ng normal arrangement of veins Sc, subcosta; R, radius, M, media; Cui, first branch of cubitus; Cut, second Dranch of cubitus; J A, first anal. (From Comctock and Netdham,)

B, front w.ng of an adult female of the narrcw-winged tree cricket

C, front wing of an immature male, showing widening of inner half to form % .braung area, or tympanum, and modification of ve.ns in this area. (From

Comstock and Needham)

D, right front w.ng of adult male of the narrow-winged tree cricket; the second branch of cub.tus {Cut) becomes the curved file vein (fv); j, the scraper

Fig. 33 The wings of a tree cricket

A, right front wing of an immature female, show.ng normal arrangement of veins Sc, subcosta; R, radius, M, media; Cui, first branch of cubitus; Cut, second Dranch of cubitus; J A, first anal. (From Comctock and Netdham,)

B, front w.ng of an adult female of the narrcw-winged tree cricket

C, front wing of an immature male, showing widening of inner half to form % .braung area, or tympanum, and modification of ve.ns in this area. (From

Comstock and Needham)

D, right front w.ng of adult male of the narrow-winged tree cricket; the second branch of cub.tus {Cut) becomes the curved file vein (fv); j, the scraper

Some crickets have large wings, some small wings, some no wings at all. The females are provided with long ovipositors for placing their eggs in twigs of trees or in the ground

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