A large number of genera have been established by various authors, but their limitations and affinities are not very well made out. Those which seem best established are the following:--
(2107-2112) _Picumnus_ (22 sp.). Tropical South America to Honduras; (2113) _Vivia_ (1 sp.), Himalayas to East Thibet; (2114) _Sasia_ (2 sp.), Nepal to Java; (2115) _Verreauxia_ (1 sp.), West Africa; _Picoides_ (5 sp.), northern parts of Nearctic and Palæarctic regions, and Mountains of East Thibet; _Picus_ (42 sp.), the whole Palæarctic, Oriental, Nearctic, and Neotropical regions; (2123) _Hyopicus_ (2 sp.), Himalayas and North China; (2124) _Yungipicus_ (16 sp.), Oriental region, and to Flores, Celebes, North China, and Japan; (2127-2129) _Sphyrapicus_ (7 sp.), Nearctic region, Mexico, and Bolivia; (2130-2133 2139) _Campephilus_ (14 sp.), Neotropical and Nearctic regions; _Hylatomus_ (1 sp.), Nearctic region; (2137 2140) _Dryocopus_ (5 sp.), Mexico to South Brazil, Central and Northern Europe; (2134) _Reinwardtipicus_ (1 sp.), Penang to Borneo; (2135 2136) _Venilia_ (2 sp.), Nepal to Borneo; _Chrysocolaptes_ (8 sp.), India and Indo-Malaya; _Dendropicus_ (16 sp.), Tropical and South Africa; _Hemicercus_ (5 sp.), Malabar and Pegu to Malaya; _Gecinus_ (18 sp.), Palæarctic and Oriental regions to Java; (2151-2156) _Dendromus_ (15 sp.), West and South Africa, Zanzibar, and Abyssinia; (2157-2159) _Mulleripicus_ (6 sp.), Malabar, Pegu, Indo-Malaya, and Celebes; _Celeus_ (17 sp.), Paraguay to Mexico; _Nesoceleus_ (sp. 8833) Cuba; (2162) _Chrysoptilus_ (9 sp.), Chili and South Brazil to Mexico; _Brachypternus_ (5 sp.), India, Ceylon, and China; (2165 2166) _Tiga_ (5 sp.), all India to Malaya; (2167) _Gecinulus_ (2 sp.), South-east Himalayas to Burmah; _Centurus_ (13 sp.), Nearctic Region to Antilles and Venezuela; _Chloronerpes_ (35 sp.), Tropical America, Hayti; (2171) _Xiphidiopicus_ (1 sp.), Cuba; _Melanerpes_ (11 sp.), Brazil to { 304}Canada, Porto Rico; _Leuconerpes_ (1 sp.), Bolivia to North Brazil; _Colaptes_ (9 sp.), La Plata and Bolivia to Arctic America, Greater Antilles; _Hypoxanthus_ (1 sp.), Venezuela and Ecuador; (2187) _Geocolaptes_ (1 sp.), South Africa; _Miglyptes_ (3 sp.), Malaya; _Micropternus_ (8 sp.), India and Ceylon to South China, Sumatra and Borneo.