146 BRITISH BUTTERFLIES 



rich yellow around them, often appear of a greenish hue. The 

 butterfly receives its popular name from this circumstance. 



A careful observer, however, will readily find distinguishing 

 marks on the upper side, for here also the chief ' veins ' are more 

 or less accompanied with black scales, especially the extremities of 

 those of the fore wings, where little triangular blotches are often 

 distinctly formed ; and the dark veining of the under surface of the 

 hind wings frequently shows through. The under side of this 

 insect is shown on Plate I (fig. 5). 



This butterfly is not so abundant as the two preceding, but is 

 widely distributed throughout England, and is in most parts 

 decidedly plentiful. 



The first brood (for it also is double -brooded) appears during 

 April and May, and the second in Juty and August. 



The eggs are very similar to those of Rapce, resembling ribbed 

 and striated sugar loaves ; and the larvae are of the same rich glaucous 

 green, but may be identified by the black spiracles surrounded by 

 yellow rings. In our gardens we may find both eggs and larvae on 

 mignonette and horse-radish ; the other food plants of this species 

 include the water-cress (Nasturtium officinale), winter cress 

 (Barbarea vulgaris), rape (Brassica Napus), cuckoo-flower 

 (Cardamine >rafe?zsis), and Jack-by-the-hedge (Sisymbriuin 

 Alliaria). 



The pupa is greenish, and marked with small black dots. 



The Bath or Green-chequered White (P. Daplidice) 



There is no doubt that many butterflies migrate from one coun- 

 try to another across the seas ; and as the Bath White is very 

 common on the other side of the Channel, and has been taken very 

 sparingly in England almost exclusively in the south-east, it is 

 highly probable that the majority of those that have been captured 

 here are specimens that have taken a voluntary trip across the 

 water, or have been blown over during rough weather. 



This butterfly is one of our greatest rarities, and the capture of a 

 specimen in England is an event that must necessarily be recorded 

 in our entomological literature. It seems that Daplidice has bred 

 in England, for its caterpillars have been found at large on one or 

 two occasions, so I will give a short description of the various 

 stages of the insect, with a hope that some of my readers may be 

 fortunate enough to meet with it. 



