524 



INSECTA. 



In the Geotrupides the antennae are generally 11-jointed, the mandibles are generally exposed and 

 curved, and the upper lip more or less exposed ; the species are generally of black or red colours, with 

 the elytra smooth or simply striated ; the males are often cornuted. They chiefly feed upon 

 excrementitious matter. 



AZgialia, Latr. (having the body short, thorax transverse and abdomen gibbous, and composed of [a single small 

 British species, found upon our sandy coasts.] Ps. arenarius, Gyll., &c.) and 



Chiron, Mac Leay, (Diasomiu, Dalm.), having the body narrow, long, and subcylindric, [and consisting of several 

 exotic species, and placed by Mac Leay amongst the Lucanidae], are both distinguished by having only nine joints 

 in the antennae ; the others have eleven joints, which are, however, sometimes difficult in computation, the joint 

 preceding the club being sometimes apparently confounded with the basal joint of the club. 



Lethrits differs from the rest in having the club obconical and the mandibles exposed, very large, serrated inter- 

 nally, and with a large tooth in the males. Lethrus cephalotes, Fabr., according to Fischer, is destructive to young 

 buds and leaves, which it bites off, whence, in Hungary, it is called " the Schneider," and where it does much 

 injury to the vines, crawling backwards, with its food in its jaws, into its hole, each of which is occupied by a male 

 and female ; but in the pairing time a strange male sometimes intrudes, when a battle ensues which only ends in 

 the death or flight of the stranger. 

 The others have the joints of the club of the antennae of the ordinary form, and leaf-like. 



Geotrupes, Latr., has the labium advanced and transversely square, the jaws are curved and very compressed, and 

 with the club of the antennae oval or ovoid, the anterior tibia; long and multidenticulate, and the clypeus lozenge- 

 shaped : ficarabams stercoral ius, Linn., [the common Dor, or Shard- 

 borne Beetle. One of the commonest British insects ; there are several 

 others, natives of this country.] Those species which have the thorax 

 of the males cornuted form the [genus Typhaus, Leach], Ceratophyus, 

 Fischer. Type, Scarabteus typhieus, Linn., [or the common English 

 Bull-comber]. 



Ochod<eus, Meg., has the labrum strongly notched, the mandibles 

 elongate, triangular, and the fore-tibiae with only two teeth on the 

 outer edge. Melolontha chrysomelina, Fab. [Germany]. 



Those species with the club of the antennae large, orbicular, or sub- 

 globose, the middle joint being encased between the two outer ones, 

 form three subgenera. 



At /iy reus, Mac Leay, approaches the Coprophagi in having the middle 

 feet wider apart than the others. 

 Elephastomus, Mac Leay, has the clypeus produced into a thick, 

 square horn, furcate at tip, and the maxillary palpi very long. Scarab, proboscideus, Schr. [New Holland]. 



Bolbocerus, Kirby (Odontitis, Zeigl.), has one of the mandibles simple, and the other bidentate at the tip ; the 

 maxillary palpi scarcely larger than the others. S. mobilicornis, Fabr., a small [rare British species, the male of 

 which has a long erect horn on the head]. 



Hybosorus, Mac Leay, (having the basal joint of the antennae obconical and elongated, the tibiae narrow and elon- 

 gated), and 



Acanthocerus (having the basal joint of the antenna? very large, dilated above, and the tibiae lamellar and con- 

 cealing the tarsi), have ten joints in the antennae, the last joint of the palpi elongate, and the mandibles not or but 

 slightly toothed. The species of both are very small [and exotic]. 



In the second division of the Arenicoli, or the Trogides, the antennas are always composed of ten 

 joints, the labrum and mandibles but slightly exposed, the maxillae armed with teeth ; the body is 

 dingy-coloured, and tubercular above ; their fore-legs are advanced, their thighs covering the head 

 beneath. These insects produce a stridulation by the action of the mesothorax against the sides of the 

 prothoracic cavity. 



Trox, Fabr. — These insects are found in the earth or sand, where they appear to devour the roots of vegetables. 

 [Trox arenarius and two other British species, of small size.] Mr. Mac Leay has separated the apterous species 

 with the sides of the thorax dilated, under the name of Phoberus. 



Cryptodus and Mcechidius, Mac Leay, have the extremity of the body not covered by the elytra, and nine joints 

 to the antennae: Maechidius appears to me to approach the Melolonthae. [Mr. Mac Leay has subsequently discovered 

 that Cryptodus belongs to the Cetoniidae. Both subgenera are Australian.] 



A third section, Xylophili, {Geotrupes and certain Cetonice, Fabr.), has the scutellum distinct, the 

 extremity of the abdomen not covered by the elytra, the claws of the tarsi often unequal, the antennae 

 always 10-jointed, the last three forming a leaf-like mass, the middle leaf never being entirely concealed 

 by the outer ones ; the mandibles horny as well as the maxillae, which are straight and often toothed. 

 All the feet are inserted at equal distances apart. [This section comprises two divisions, corresponding 

 with the families Dynastidce and Rutelidce, Mac Leay.] 



The first division (comprising the Geotrupes of Fabricius) comprises those species, the males of which 



Fig. 69. — Geotrupes Blercorariul. 



