COLEOPTERA. 75 



orbicular. The elytra are frequently somewhat inclined laterally, or 

 tectifonn, flattened, and rounded. These Insects simulate death when 

 they are seized, and several, thus situated, produce a caustic yellowish 

 liquid of a penetrating odour, from the articulations of their feet ; 

 the organs which secrete it have not yet been detected. 



Various species — Meloes, Mijlabres, Cantharides — are employed 

 externally as epispastics, and internally as a powerful stimulant; the 

 latter use of them, however, is extremely dangerous. 



This tribe is formed of the genus 



Meloe, Lin., 

 Which has been divided into several others. The anatomical ob- 

 servations of M. Leon Dufour, Avith the highly interesting experi- 

 ments of Dr. Bretonneau, of Tours, on the vesicating property of the 

 Insects of this tribe, and of several other Coleoptera, enable us to 

 arrange these generic sections in a natural order, Avhich differs but 

 little from that we have already adopted. The latter gentleman has 

 ascertained that the Sitares do not possess the property in question, 

 and the former found but four biliary vessels in the same Heteromera, 

 instead of six, which exist in the other Insects of this tribe. Indepen- 

 dently of this, Sitaris resembles Zonitis in the whole ensemble of the 

 organization, and these latter are contiguous to the Cantharides. 

 These Insects thus occupying one of the extremities of this tribe, it 

 is easy, by a comparative study of their other relations, to follow the 

 series until we reach the opposite extremity — it accords with the 

 progressive changes in the form of the antennae. 



In some, those of both sexes consist of but nine joints, the last of 

 which is very large, and in the form of an ovoid head * ; those of the 

 males, as well as their maxillary palpi, are very irregular. The body 

 is depressed. Such is the 



Cerocoma, Geoff. Schceff. Fab. 



These Insects make their appearance during the summer solstice, 

 and frequently in great numbers in the same spot ; they are found on 

 flowers, particularly on those of the wild Chamomile, the Milfoil &c. 

 C. Schcefferi ; Meloe Schrefferi, L. ; Oliv., Col,, III, 48, i, 1. 

 Green or bluish-green ; antennae and feet of a wax-yellow f. 



In all the others, the palpi are identical and irregular in both sexes. 

 The antennae usually consist of eleven joints, and when there is one 

 or two less, they ahvays terminate regularly in a club. The body is 

 tolerably thick, and the elytra are somewhat inclined. 



In these, the antennae, always regular and granose in both sexes, 

 sometimes appearing to be composed of nine or ten joints |, and 



* All the Insects of this tribe with clavate antennae, or such as are larger near 

 the end, are foreign to New Holland and America. 



t See Lat., Gener. Crust, et Insect., II, p. 212; Olivier, Fabricius, Schoenherr, 

 and Fischer, Entomog. Imp. Ross., II, xli, 1, 2, 3. 4. 



X The two or three last ones appear to be confounded or intimately united, at 

 least in the females ; for the articulations of the claube more distinct in th 

 males. 



g2 



