THE REVISION OF THE SPHINGIDES, 9 



figures, it will be evident that we are well within the limits of simple 

 fact in regarding this portion of the work as a new departure, not so 

 much in method as in the thorough application of it. No doubt the 

 great majority of these plates are devoted to $ and $ genitalia, and 

 genitalia have been very satisfactorily dealt with in various mono- 

 graphs, but the series of draAvings of the armature of the aedoeagus 

 (penis-sheath) are such as we have not seen in regard to any other 

 group of lepidoptera. The drawings and their reproductions in these 

 plates have no need to fear even the most jealous hypercriticism. 

 The remaining 16 plates are of imagines, photographed of natural 

 size — seven in colours, the remainder in black and white. Those 

 in black and white, attributed by legend to S. G. Payne and Son, are 

 of remarkable success. 



Geographical distribution occupies the remaining 38 pages of 

 general matter. As a geographical barrier, it is pointed out that 

 there are not only oceans and mountains, but climatic differences 

 that foodplant, competitive species, and other forces may be equally 

 effective. The main portion of this section of the essay deals with 

 detailed items not admitting of brief presentation. The temperate 

 regions contain only one in seven of known species, and the tropical 

 species still to be discovered will probably reduce the proportion to 

 1 in 9. Chili has only two species of hawk moths. The summary of 

 the Palfearctic fauna is as under : — 



7 genera and 52 species are peculiar to the region. 

 4 ,, ,, 1 ,, occur also in the New World. 



1 genus is found in the Nearctic and Oriental regions. 

 13 genera ,, 16 species occur also in the Oriental region. 



6 ,, ,,3 ,, ,, ,, ,, and yEthiopian regions. 



2 ,, ,, ,, Ethiopian regions. 



2 ,, ,, 1 ,, are cosmopolitan. 



33 ,, ,,75 species. 



The northward extension of southern forms is much more marked 

 eastwards, as it is in the Nearctic region. The details of the several 

 genera and species emphasise the pytiiid facie view that the Sphint/ides 

 are not by any means native to the Palaearctic region, but have 

 immigrated at various times from various directions, and one ends by 

 being rather astonished that so many have succeeded in staying so 

 long and becoming more or less peculiar to the region. The most 

 peculiar item is that of the small remnant of the Sphimjulicae, perhaps 

 the nearest that remains to the primeval Sphingid, 6 species out of 11 

 should inhabit the eastern Pal^arctic area. 



We do not always find exact accordance between the table on 

 p. cvii and the detailed tables, but they are near enough. It appears 

 that the Neotropical fauna, in not far from its entirety, consists of 

 species, and to a large extent genera, that are special to it. The 

 Sesiinae are almost confined to the region, having 14 special genera, 

 and seven others that extend to the Nearctic region, leaving only 

 three outside it, which reach the eastern hemisphere, one of these 

 being also Palfearctic. The Choerocampinae are in almost the opposite 

 position, with 11 Old World genera, and only three reaching the 

 Neotropical region, of which two are special ; but these, though 

 presumably immigrants, have thriven, and possess 53 species confined 

 to the region, against 86 in the 11 eastern genera. 



