INSECTA. 567 



domen is embraced by the elytra, as in Mastigus and Scyd- 

 manus. In others, the neck is concealed, as in Malachiu- 

 sidae, which exhibit, as a peculiar character, four vesicles 

 divided into lobes, under the thorax and the base of the 

 abdomen, which can be withdrawn or exerted and inflated 

 at pleasure. The Melyridae have the palpi filiform, as Me- 

 lyris, Dasytes, and Drilus; while in Clerusidas, the palpi 

 are securiform as Clerus, Tillus, and Enoplium. 



In those families where the body and elytra are firm and 

 crustaceous, the Ptinusidae have the head and thorax nar- 

 rower than the abdomen, witli the antennae about the length 

 of the body as Ptinus and Gibbium ; and the Anobiume- 

 dae, having the thorax of the size of the abdomen, and the 

 antennae much shorter than the body, as Anobium, Ptile- 

 nus, and Dorcatoma. 



There are several genera which agree with some of the 

 preceding in the softness of their bodies, but having man- 

 dibles entire at the apex. In some of these, the palpi 

 are filiform, as in the Cebrionidae, which have tarsal joints 

 entire, as Cebrio and Hammonia ; and in Scirtesidae, which 

 have the penultimate joint of the tarsus bifid, as Scirtes, 

 Elodes, Rhipicera, and Dascillus In others, the palpi, 

 especially the maxillary ones, become thicker towards the 

 extremities. In the Lampyridas the antennae are approxi- 

 mate at the base, and the maxillary are longer than the 

 labial palpi, as in Lampyrus, Lycus, and Omalisus. In 

 the Telcphoridae, the antennae at the base arc remote, and 

 the labial and maxillary palpi are nearly of equal length, 

 as in Telephorus and Malthinus. 



IV. Pentamera Clavicounua. — The antennae arc 

 here obviously club-shaped, pcrfoliated or solid, generally 

 exposed at the base, and longer than the maxillary palpi. 

 In a few genera, forming the family Dryopsidae,^ the first 

 and second joints of the antennae are enlarged, and the re- 



