( CSXIV ) 



Tlie lai'ger proiiortioii nf the genera and species occnrring in the Palaearctic 

 Region are of Oriental extraction. Those of the Atlantic Snbregion have come 

 over Afghanistan ami Persia, those of the Pacific Snbregion over China. Tea 

 of the genera do not occnr in the Oriental and Aethiopian Regions, to which 

 number mnst be added Haemorrliagiu, which is not of Tropical Old World origin, 

 and Dolbhin, which extends only into North India. Of the tea genera characteristic 

 of the Palaearctic Region, two are of American descent (Ili/loicus and Ilaemor- 

 rliagia). When discussing the Nearctic Spliingidae, we drew attention to the fact 

 that the trojiical Jfi/loicus are more generalised than the Nearctic ones. A similar 

 ])hpnouienou obtains in other genera. The European Manimba quercus is more 

 specialised than the Oiiental species of the genus and than sperchiiis. The 

 Syrian AMifsiu is more sj)ecialised than the Aethiopian Batocnema, its nearest 

 ally. The youngest member of ('(tUambuhjx is the Palaearctic tuturinoxi, the 

 Oriental nihricom being tlic oldest. The most aberrant species of Sphinx is 

 the Nearctic '/(tmaimisis {=gi'minutus), and the genus Sphinx has given rise in 

 North America to the specialised genus Calasi/mbolun. Of the various subspecies 

 of Sphinx cerisi/i, the Mexican one is the most generalised. The American 

 Pachi/sphinx, Monanla, and Cressonia are younger members of that same 

 branch than is the Palaearctic Amorpha, and this is much more specialised 

 than the Oriental CaUambubjx, The Syrian genus BeriUana and the Nearctic 

 genera Ampclueca and Darapsa are derivations from the Oriental genus Ampelo- 

 phaga. The southern Palaearctic species of llaemorrhagia (croatica, dentaia, 

 rubra, ducalis) have kejit the complete or nearly complete covering of scales 

 to the wings, which the mimetic sjiecies have lost ; tiie Atlantic Nearctic 

 llaemorrhagia gracilis and tki/sbe are also more generalised than diffinis and 

 brucei ; and Proserpiiius gaurac and jiianita more than the Pacific sjtecies of 

 the genus and its derivative Euproserpiinis. The most specialised sj)ecies 

 of tiie cosmopolitan genus Cderio arc Palaearctic, and the two genera which 

 have branched off from Cderio are Sonlh African and Palaearctic. Macro- 

 glossum stellatarum is in structure and colour one of the most specialised 

 species of this large Afro-Oriental genus. Orecta, inhabiting temperate South 

 America, but extending beyond the Tropic of Capricorn, is a derivation from 

 the essentially tropical genus Amplypterus. These cases show that the extra- 

 tropical Sphiiigidae are derivations from a tropical fauna, and that specialisation is 

 generally highest in the districts farthest from the original country. 



There are some apparent excei>tions which, on closer inspection, only prove 

 the rule. Dolba of North America is more generalised than Dolbogenn from 

 Mexico ; Dolbina incxai-la from North India more specialised than D. tancrei 

 from Amnrland and Japan ; Thamiioecha from North India more than the 

 Palaearctic Hgloicus, and Dolbinopsis from North West India more than the 

 essentially Palaearctic genus llolbi)ia. lu all these cases the southern Sphinx 

 is a derivation from the northern, these insects being acquisitions from the 

 Temjjerate Zone, existing only in the borderlands of the Tropics. 



The Oriental Region is not larger in extent than the Neotropical and 



