COMMON BUTTERFLIES OF THE PLAINS OF INDIA. 37 



individnais are naturally >!mall, and oenerally li^lit in oolonr and 

 inarkings, when usual, tend to disappear. 



Sufficient has now been said in the way of Introduction. Be- 

 low will be found the keys to the families, sub-families, genera and 

 species dealt with in these papers. These keys have been formed as 

 much as possible on well defined and clearly visible qualities of shape, 

 markino- and colouration and as little recourse as possible has been 

 had to the more obscure characters of venation of the wings, form of 

 legs, sexual characters, &c. It has been found unavoidable altogether 

 to steer clear of them, however, in several cases and it is feared that 

 this may offer difficulties to the uninitiated. Any wav, it cannot be 

 helped and it is hoped that, with the use of benzine and a good lens, 

 combined with patience, these difficulties may not prove unsur- 

 mountable. The best form of lens for the examination of the wing- 

 veins, &c., is a " Coddington " which can be purchased for a few 

 rupees and is small and portable. 



The Plates are three-colour prints from original handpaintings 

 by Mr. Horace Knight which are perfection itself if we except the 

 shade of Papilio daksha 9 — it is not dark enough and was probably 

 taken from a somewhat faded specimen — and Catochrysops straho 

 where the small subcostal spot beyond the discocellulars on the under- 

 side of the forewing has been omitted. The shade of the prints is 

 always somewhat too dull and they in no case do justice to the origi- 

 nals in purity of colour and clearness, although this in no way inter- 

 feres with the fact that the insects figured cannot be mistaken for 

 anything but what they are : which is all that is required. The light 

 blue colour, particularly, always comes out too dark in the prints. 

 The wood-cuts are nearly all reproductions of those used by Colonel 

 Bingham in his work and the blocks were kindly lent to the Society 

 by the courtesy of the Secretary of State for India. 



Most of the descriptions of the imagines or perfect insects are taken 

 from Colonel Bingham's work, as far as available. 



Butterflies are classed under the following six families in India. 

 Those treated of in these papers are representative of all six. Colonel 

 Bingham's key to the families is as under : — 



A. Antennae close together at base ; hind tibiae with 

 only a terminal pair of spurs ; one or more veins 



