CHAP. xxi. j INSECTS. 487 



Palasarctic has 2, but none peculiar ; the Ethiopian 13, with 11 

 peculiar ; the Oriental 8, with 3 peculiar ; the Australian 9, with 

 2 peculiar; and the Neotropical 15, with 10 peculiar. The 

 connection between South America and Australia is shown by 

 the latter country possessing 9 species of the characteristic 

 South American genus Tetracha, as well as one of Megacephala. 

 The small number of peculiar genera in the Oriental and. Aus- 

 tralian regions is partly owing to the circumstance that two 

 otherwise peculiar Oriental genera have spread eastward to the 

 Moluccas and New Guinea, a fact to be easily explained by the 

 great facilities such creatures have for passing narrow straits, and 

 by the almost identical physical conditions in the Malayan portion 

 of the two regions. The insects of Indo-Malaya were better 

 adapted to live in the Austro-Malay Islands than those of 

 Australia itself, and the latter group of islands have thus ac- 

 quired an Oriental aspect in their entomology, though not with- 

 out indications of the presence of an aboriginal insect-fauna of a 

 strictly Australian type. The relation of the Australian and 

 Neotropical regions is exhibited by this family in an unusually 

 distinct manner. Tetracha, a genus which ranges from Mexico 

 to La Plata, has 9 species in Australia ; while Megacephala has 

 2 American and 1 Australian species. Another curious, and 

 more obscure relation, is that between the faunas of Tropical 

 America and Tropical Africa. This is also illustrated by the 

 genus Megacephala, which has 4 African species as well as 2 

 South American ; and we have also the genus Peridexia, which 

 has 2 species in South America and 2 in Madagascar. 



Several of the sub-regions are also well characterised by pecu- 

 liar genera ; as AmblycJiila and Omus confined to California and 

 the Eocky Mountains ; Manticora, Ophryodera, PlatycKile, and 

 Dromica, characteristic of South Africa; Megalomma and Pogonos- 

 toma peculiar to the Mascarene Islands ; and Caledonica to the 

 islands east of New Guinea. The extensive and elegant genus 

 Collyris is highly characteristic of the Oriental region, over the 

 whole of which it extends, only just passing the limits into 

 Celebes and Timor. 



The Cicindelidse, therefore, fully conform to those divisions of 



YOL. II 32 



