CHAP. XXI.] INSECTS. 4 83 



North and South America ; Snurinthus (29 sp.), all regions 

 except Australia. Our Death's Head Moth (Acheroiitia atropos) 

 ranges to Sierra Leone and the Philippine Islands. 



General Remarks on the Distrihiition of the Diurnal Lejndoplcra 

 and Sphingidea. 



The Diurnal Lepidoptera or Butterflies, comprehend 431 

 genera and 7,740 species, arranged in 16 families, according to 

 Mr. Kirby's Catalogue published in 1871. The Spliingidea con- 

 sist of 135 genera and 1,255 species, arranged in 7 families, 

 according to the British Museum Catalogue dated 18G4 ; and as 

 this includes all Mr. Bates' collections in America and my own 

 in the East, it is probable that no very large additions have 

 since been made. 



The distribution of the families and genera of Butterflies 

 corresponds generally with that of Birds — and more especially 

 with that of the Passerine birds — in showing a primary division of 

 the earth into Eastern and Western, rather than into Xorthern and 

 Southern lands. The Neotropical region is by far the richest and 

 most peculiar. It possesses 15 families of butterflies, whereas the 

 other regions have only from 8, in the PaUearctic, to 12 in the 

 Ethiopian and Oriental regions ; and as none of the Old World 

 regions possess any peculiar families, the New World has a very 

 clear superiority. In genera the preponderance is still greater, 

 since the Neotropical region possesses about 200 altogether 

 peculiar to it, out of a total of 431 genera, many of which are 

 cosmopolitan. Comparing, now, the Eastern regions with the 

 AVestern, we have two peculiar families in the former to 4 in the 

 latter ; while the Southern regions (Australian and Neotropical) 

 possess not a single peculiar family in common. 



In the Sjjhingidea the same general features recur in a less 

 marked degree, the Neotropical being the richest region ; but 

 here we have one family (Castniida^) which appears to be con- 

 fined to the two southern regions, — the Australian and Neo- 

 tropical. 



The distribution of the genera affords us some facts of special 

 interest, which must be briefly noticed. There are several 



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