408 



Observations on the various Insects 



form of woodlice {Onisci) as shown at fig. 15, but are black and 

 shininn^; comprising 13 segments, including the head, which is some- 

 what orbicular, with two impressions on the face ; and the mouth is 

 composed of 5 pieces: 2 mandibles or jaws (fig. 11), which are horny, 

 cleft at the apex, forming 2 sharp minutely serrated teeth, and inside is 

 a duplicate lobe (fig. 18), of similar form, but shorter ; this is a member 

 which I have not met with previously, and has no analogue in the 

 perfect beetle. Below the mandibles are two secondary jaws called 

 maxillae (fig. 19), which are articulated and terminated by a broad 

 hairy lobe, and to the outside is attached a longish palpus or feeler 

 (fig. g}^ which is 4-jointed, the apical joint conical ; between these is 

 placed the chin (fig. 20), with a short cleft lip (fig. h), and on either 

 side is a short stout tri-articulate palpus or feeler (ngs. i i) : the eyes 

 are composed of 4 minute lenses, situated above the antennae, which are 

 inserted in cups on each side of the head; they are rather short, slender, 

 hairy, and 3-jointed (fig. 21) ; the basal joint is cylindrical and scarcely 

 longer than the second, which appears to be notched inside near the 

 apex, the third is slenderer and elongated : the thorax comprises 3 seg- 

 ments, the first being the largest; they have the angles rounded, but 

 in the following segments they are acute and give the sides a toothed 

 appearance ; the apical segment, however, is furnished with an acute 

 spine on each side. It has 6 short legs, which are 5-jointed; being 

 formed of a iiip, trochanter, a thick thigh, slender shank, and a strong 

 acute claw (fig. 22). In some specimens the body had a narrow tawny 

 margin (fig. 15), whilst others were narrower and more elongated 

 (fig. 16;/, the natural length.) When full-grown the larvse bury them- 

 selves, and forming cells, change to pupa? in the earth, and from these 

 emerge the beetles called 



2. Silpha opacaby Linne, but De Geer named them S. tomerdosa, from 

 their being clothed with short, tawny, depressed hairs, which are generally 

 worn off in a short time, when they appear black, and exceedingly thickly 

 punctured all over, the hairs having been inserted in these minute pores : 

 the head is very much the form of that of the larva, and the organs of 

 the mouth are not very dissimilar,* but the eyes are large and oval, the 

 horns are twice as long, clubbed, and 1 l-jointed ; basal jointthe longest, 

 2nd longer than the third, 5 following more or less globose, the re- 

 mainder forming a sort of club, the terminal joint reverse — pear-shaped : 

 the thorax is twice as broad as the head, somewhat transverse-oval, the 

 surface undulating from impressions ; scutellum rather large and trian- 

 gular : wing-cases depressed, yet slightly convex, the outer margin 

 reflexed, and there are three fine sharp ridges down each, curved next 

 the hinder margin, which they do not reach, the outer one being consi- 

 derably the shortest, and beyond the middle is a bump between the 2nd 

 and 3rd striae : the wings are ample, and folded in repose : the 6 legs 

 are stoutest in the 7nale (fig. 23) ; the shanks are spiny and spurred at 

 the apex ; the feet are bristly and 5-jointed, the 4 anterior with the 4 

 first joints dilated in the male, especially the first pair ; 5th joint clavate, 



* Curtis's Brit. Ent., fob and pi. 742, where dissections and a coloured 

 figure of the beetle are given. 



