462 INSECT A. 



and all the joints of the tarsi are entire, and terminated 

 by single hooks ; the anterior tibiae are frequently broad and 

 triangular. Several males have the head furnished with horns. 

 Most of them inhabit the fungi on trees, or under the bark ; 

 some live on the ground, under stones. 



M. Leon Dufour has observed in certain subgenera of this 

 family, such as Hypophlaeus, Diaperis proper, Eledona or 

 Boletophagus, an excrementitious apparatus, and in the second 

 salivary vessels. The chylific ventricle of these Heteromera 

 is bristled with little piliform papillae. These characters, and 

 the conformation of the organs of generation, point out the 

 connexion between this and the preceding family(l). 



In some, the head is completely exposed, and never entirely 

 received into a deep notch in the anterior of the thorax. 

 This last is sometimes trapezoidal or square, and at others 

 almost cylindrical ; its sides, as well as those of the elytra, do 

 not extend remarkably beyond the body. 



This division will form the tribe of the Diaperiales, the 

 type of which is the genus 



Diaperis. 



Sometimes the antennae are generally stout, almost straight, and 

 mostly perfoliate, or terminated abruptly by a thick club. The body 

 is smooth, or the elytra are lightly striated. The sides of the tho- 

 rax have but a slight border, and are neither depressed nor dentated; 

 there is no remarkable separation nor hiatus between its posterior 

 angles and the base of the elytra. The two anterior legs are trian- 

 gular, and dilated exteriorly at the extremity, in a great number. 



Here the antennae enlarge insensibly, or at least are not abruptly 

 terminated by an oval or ovoid club, of which most of the joints are 

 larger than the preceding ones. 



In some, and the greater number, the body is oval or ovoid, some- 

 times even hemispherical, with the thorax either nearly square or 

 trapezoidal, most frequently transversal, but never long and narrow. 



(1) It is the same with the following one. The transition from Tenebrio to 

 Pluileria and Helops, is almost insensible, and consequently the characters of these 

 families, in some cases, are ambiguous. 



