360 INSECTA. 



larva; are pilose, and mostly feed on the exuviae or carcasses of animals. Several 

 are very injurious to entomological collections. 



Those then in which the legs are not completely retractile, the tarsi being 

 always free, and the tibiae elongated and narrow, form our seventh tribe, that 

 of the DERMESTIM, and the great genus 



DERMESTES. 



In Dermestes, properly so called, the antennae are similar, or differ but very 

 slightly in both sexes ; the length of the last joint is never much greater than 

 that of the preceding ones. 



Some of the species do great injury among furs, and devastate our collections 

 of natural history. De Geer calls them dissectors, and in fact the Dermestes 

 Inrdarius cuts to pieces the Insects of the cabinet into which it has penetrated. 

 The others devour the dead bodies of all kinds of animals. 



D. lardarius, Lat. Black ; base of the elytra cinereous and dotted with black. 

 The larvae is elongated, insensibly tapered from head to tail, of a chestnut- 

 brown above, white beneath, furnished with long hairs and two squamous 

 horns on the last annulus. 



There are various other Dermestini arranged in different genera, such as 

 Attagenus, Megatoma, Anthrenus, &c. 



The eighth tribe, that of the BYRRHII, differs from the preceding in the 

 perfect contractility of the legs; the tibiae are susceptible of being flexed on 

 the thighs, and the tarsi on the tibiae, so that when thus folded and pressed 

 against the body, the animal seems to be inanimate and entirely destitute of 

 feet. The tibia? are usually broad and compressed. The body is short and 

 convex. 



This tribe is chiefly composed of the genus 



BYRRHUS, Linnaeus. 



The mentum of the true Byrrhii is of an ordinary size and interlocked (at 

 least partially) by the praesternum, whose anterior extremity is dilated. 



In some, the antennae enlarge insensibly, or terminate in an elongated club 

 formed of from five to six joints. 



B. pittda, L. From three to four lines in length ; black beneath, blackish- 

 bronze or soot-colour and silky above, with little black spots mingled with 

 lighter ones arranged in lines. 



All the Byrrhii remain on the ground in sandy localities. 



It is impossible to describe the Clavicornes of our second section, although a 

 very natural one, but by the reunion of several characters. 



The body of these Insects is generally ovoid, and their head plunged to the 

 eyes in a trapezoidal thorax, with a recurved lateral margin, and terminating 

 posteriorly in acute angles; the prtesternum is dilated anteriorly and the legs 

 are imperfectly contractile. They are found in the water, under stones in the 

 virinity of shores, and frequently in the mud: some of them Dryops are 

 allied to the Gyrini by the structure and shortness of their antennae. 



