INSECTA. 569 



the legs are flattened, and formed for swimming, as Hydro- 

 philus, Spercheus, Elophorus, and Hydraena. In the 

 Spheridiada*, the five joints of the tarsus are distinct, as in 

 Spheridium and Cercyon. 



VI. PENTAMERA LAMELLICORNUA. The insects of this 

 division are readily recognised by their club-shaped an- 

 tennae, the extremity of which is divided into laminae, ca- 

 pable of receding or approaching at pleasure. The Lu- 

 canidae differ from all the rest of this tribe in the lamina? 

 of the club of the antenna?, being placed (not as in the 

 other families, approximating at the base, and opening and 

 shutting like the leaves of a book, but) like the teeth of a 

 comb, perpendicular to the axis, as Lucanus, Sinodendron, 

 Esalus, Lamprina, Platyceres, and Passalus. In the Co- 

 pridae, the membranaceous termination of the maxillae is 

 large and transverse ; the antennae have eight or nine 

 joints ; the labrum is concealed by the semicircular margin 

 of the head ; the mandibles are soft ; and the last joint of 

 the labial palpi comparatively small, as Copris, Aleuchus, 

 and Aphodius. The Geotrupidae have the terminal joint 

 of the labial palpi as large as the preceding one ; the an- 

 tennae have eleven joints, and the mandibles are horny, as 

 Geotrupes, Lethrus, and Typhaeus. In the Scarabeidae 

 the antennae have nine joints. The labium is concealed by 

 the mentum, as Scarabeus, Trox, Egialia, Oryctes, Hexo- 

 don, and Rutella. The Melolonthadae have the mandi- 

 bles greatly concealed by the head and the maxillae, as 

 Melolontha and Anoplognathus. In the Glaphyridae the 

 labium is advanced and divided into three lobes, as Glaphy- 

 rus, Amphicoma, and Anisonix. The Trichiadae have 

 membranaceous mandibles, as Trichius, Goliathus, Ce- 

 tonia, and Crematoschalus. 



II. COLEOPTERA HETEROMERA. The insects belong- 

 ing to this great subdivision have the tarsi of the fore and 



