COLEOPTERA. — GEOTUUPID.T;. 



201 



Petalocera, which must be clearly unnatural ; whilst, on the other 

 hand, if we look at the groups per se, and as of equal rank, we find 

 the Xylophili composed of a most heterogeneous assemblage. I sliall 

 therefore adopt the groups proposed by Mr. MacLeay, observing only 

 that they appear to be of equivalent rank with the divisions of the 

 Carabidse, and which it would be more convenient (in order to retain 

 the Linnaean name Scarabaeus, in its Linngean extent) to regard as 

 subfamilies, in the same manner as I have dealt with the Brachinides, 

 &c. 



The first of Mr. MacLeay 's families, GEOXRUPiDyE, is distinguished 

 by the membranaceous structure of the maxillary lobes (^(/. 20. 4.), 



Fit/. 20. 



ir, 



by the porrected, curved, and horny mandibles (Jiff- 20. 2, and 20. 3.), 

 the elytra rounded behind, and entirely covering the abdomen ; the 

 tibiae broad and toothed ; the labruni exposed (Jig. 20. 2.), as well as 

 the labium, which is bilobed (Jig. 20. 5. and 20. G.) ; the fleshy tongue, 

 large and internal (y/^/. 2Q. 6.) ; antennae 10 or 11-jointed, the club 

 large, subglobose, and 3-jointed, the middle joint of the club encased 

 in the preceding (Jig. 20. 7, 8.) ; the body short, thick, and convex, 

 generally of a black colour {Jig. 20. i. Geotrupcs vernal is) ; the 

 elytra smooth, or simply striated ; the males, in some species, are 

 furnished with horns, or other sexual peculiarities ; the thorax is 

 broader than long ; the scutellum generally distinct. 



These insects perform an important part in the economy of nature, 

 by feeding upon and burrowing under newly fallen dung ; thus not only 

 diminishing the quantity of cxcremcntitious matter, by devouring it, 

 but also contributing to its dissemination in the earth, by the burrous 



