434 MR. W, P. KIRBY ON THE GEOGRAPHICAL DISTRIBUTION OF 



cies of birds as about 650, or one species for each 21,000 square 

 miles. The proportion of butterflies is apparently somewhat less, 

 being one species for each 22,222 miles. This is no doubt partly 

 owing to incomplete observations, and partly to butterflies being, 

 for various reasons, more local than birds. It appears, however, 

 that butterflies are really less abundant in the Palsearctic region 

 than birds ; for Dr. Staudinger's last Catalogue, which takes in the 

 whole district except Japan, Thibet, and North China, enume- 

 rates only 456 species, whereas Dr. Sclater enumerates 581 birds 

 as inhabitants of Europe alone. 



II. JEthiopian or Western Ealcsotropical Region. 



"Extent. — Africa south of the Atlas range, Madagascar, Bour- 

 bon, Mauritius, Socotra, and probably Arabia up to the Persian 

 Gulf, south of 33° north latitude; an approximate area of 

 12,000,000 square miles." 



Characteristic forms. — Amattris, Gnophodes, Leptoneura, Bicy- 

 clus, Heteropsis (Madagascar), Ccenyra, Acrcea, Lachnoptera, 

 Precis, Salamis, Crenis, Euxanthe, Amphidema, Eseudacrcea, Ca- 

 tuna, Euryphene, Euphcedra, Hamanumida, Aterica, Cymothoe, 

 Meneris, Charaxes, Palla, Pentila, Liptena, U JJrbania, Axiocerses, 

 Aphnceus? Capys, Ehytala, Epitola, Heivitsonia, Deloneura, Eseu- 

 dopontia, Belenois, Idmais, Teracolus, Callosune, Abantis, Ceratri- 

 chia, JLeucochitonea, Caprona, Cyclopides. 



Africa possesses a great number of peculiar s forms, which com- 

 pensate in some measure for the absence of most of the charac- 

 teristic Palsearctic or Indian genera, and for the very sparing 

 manner in which most of the remainder are represented (by one 

 or two species only): especially remarkable is the small number of 

 Satyrince (barely fifty species) known to inhabit the Ethiopian 

 region. Strange to say, Madagascar and the adjacent islands 

 possess very few characteristic groups among the Mhopalocera. 

 Nearly all the species belong to well-known African genera, and 

 are in many cases identical with those of the mainland. The 

 fauna of Africa and Madagascar has more affinity with that of 

 India than with that of Europe, but is far more removed from either 

 than they are from each other. I must not forget to allude here 

 to the moth Chrysiridia rhipheus, which, though a Mascarene in- 

 sect, has no very close affinity to any Old-World species, but is 

 nearest allied to the Tropical- American genus Urania *. Similarly 



* Since the above was written, a second species of Chrysiridia lias been de- 

 scribed from Zanzibar (C. Croesus, Grerst.). 



