INSECT VARIETY. 193 



resembling those produced by scraping a piece of silk-woven 

 fabric, or a stiff tooth-brush, with one^s finger-nails. The 

 musical apparatus of these and other scorpions, from which notes 

 can be elicited in dry and alcoholic specimens by friction of the 

 parts, is stated to be dujjlicate. The clasp, thickly beset with 

 stout, conical, curved and sharj) spinules, is situated on a slightly 

 raised oval area, of lighter coloration than the surroimding 

 chitine, and placed outwardly, at the base of the basal joint of 

 the palp-fingers ; while the lima, crowdedly studded with minute 

 tubercles, shaped like the tops of mushrooms, is similarly situated 

 on the produced inner face of the corresponding joint of the 

 first pair of legs. 



Crustacea crepitate when alarmed, &c. Mr. Saville Kent found 

 that a small Spheroma, a species of the Isopodous order, which he 

 kept in a glass jar, made a sharp "tapping" sound, produced 

 three or four times consecutively with intervals of about one 

 second's duration ; but he failed to determine the cause, as on 

 being approached this little creature always eluded notice by 

 passing to the opposite side of his stalk of seaweed. Among the 

 Decapodous crustaceans, the genus Alplieus and allies produce 

 " clicking ■" noises beneath the water, by a sudden extension of 

 the terminal joint of their larger claw, familiar to those who 

 have searched for animals on coral-reefs, or dredged in tropical 

 seas. One collected by Mr. Kent in Guernsey, Alphem ruber, 

 emitted a " snapping " noise audible at a considerable distance, 

 that at once betrayed its lurking-place. The large sea crayfish, 

 or thorny lobster of the London and Paris fish-markets, is 

 stated to emit, on handling, a " shrill squeaking " sound by 

 rubbing together the spinous abdominal segments. The organs 

 of stridulation in Crustacea, according to Mr. Wood Mason, are 

 paired as in Arachnida and Insecta. In some the scrapers are on 

 the carapace, and the rasps on a pair of appendages, as in both 

 sexes of Matuta ; or the structures are transposed, as in the males 

 of Macrophtlialmus and allies, in which the scraper is formed by 

 a sharp-edged lamellar projection on the meropodite of each 

 cheliped, and the rasp is the crenulated infra-orbital margin. 

 In other species, the lima and clasp are on different parts of the 

 same appendages, as in male Ocypoda ; or on two pairs of 

 appendages, as in those of Platijonclim bipsutulosiis. 



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