The arrangement dependent on the number of tarsal segments - the order being divided into tribes Pentamera, Tetramera, Heteromera and Trimera - was suggested by E.
Sharp (1899), who divides the order into six great series of families: Lamellicornia (including the chafers and stag-beetles and their allies with five-segmented feet and plate-like terminal segments to the feelers); Adephaga (carnivorous, terrestrial and aquatic beetles, all with five foot-segments); Polymorpha (including a heterogeneous assembly of families that cannot be fitted into any of the other groups); Heteromera (beetles with the fore and intermediate feet five-segmented, and the hind-feet four-segmented); Phytophaga (including the leaf-beetles, and longhorns, distinguished by the apparently four-segmented feet), and Rhynchophora (the weevils and their allies, with head prolonged into a snout, and feet with four segments).
Lameere (1900) has suggested three sub-orders, the Cantharidif ormia (including the Phytophaga, the Heteromera, the Rhynchophora and most of the Polymorpha of Sharp's classification), the Staphyliniformia (including the rove-beetles, carrion-beetles and a few allied' amilies of Sharp's Polymorpha), and the Carabidiformia (Adephaga).
The most interesting of the Heteromera, and perhaps of all the Coleoptera, are some beetles which pass through two or more larval forms in the course of the life-history (hypermetamorphosis).
Towards this Lycoid centre have converged Coleoptera (beetles) of the sub-order Lamellicornia (Copridae), Phytophaga; Heteromera (Cantharidae) and Longicornia; Hemiptera of the families Pyrrhocoridae, Lygaeidae and Reduviidae; Lepidoptera of the families Arctiidae and Zygaenidae; Diptera of the family Asilidae; and lastly Hymenoptera of the families Braconidae, Pompilidae, Crabronidae and Eumenidae.
Heteromera, the narrow pinnae are dichotomously branched almost to the base (fig.