No spot can be pointed out where one can expect to meet with this fine insect; but it has appeared singly at intervals in the following localities among others:—Scotland, Ayrshire; Durham; Scarborough; York; Darlington; Sheffield; Manchester; Lake District; Appleby; Coventry; Peterborough; Oxford; Burton-on-Trent; Norfolk; Lincolnshire; Suffolk; Bristol; Ely; Shrewsbury; Plymouth; Teignmouth; Kent; Ashford; Bromley; Tenterden; Ramsgate; various places in neighbourhood of London; Epping; Hampshire; Isle of Wight; Lewes; Worthing.
On the Continent this is a common butterfly, in many places being the most abundant of all the Vanessas.
THE LARGE TORTOISESHELL BUTTERFLY. (Vanessa Polychloros.)
([Plate IX]. fig. 1.)
The beginner often has a slight difficulty in finding a good and permanent distinction between this species and the next (V. Urticæ). At the first blush, the superior size of this seems to be a sufficient mark, and then the orange of the wings has usually a much browner, or more tawny hue, than that of Urticæ; but as I have seen specimens of Polychloros absolutely smaller than some very large Urticæ's, and as the colour of both occasionally varies, so that they approach each other in this respect also, it is evident we must look for some better mark of distinction; and here is one. In Polychloros, all the light markings between the black spots on the upper edge of the front wing are yellow, whereas in Urticæ the outer one next the blue and black border is pure pearly WHITE. The two other marks on the front edge are yellow. Polychloros has also, near the lower corner of the front wing, an extra black spot, not found in Urticæ.
The blue spots on the border are in this species almost confined to the hind wings.
The caterpillar generally feeds on the elm, whence the butterfly is occasionally called the "Elm Butterfly," but it has also been found on the willow, and on the white beam-tree. Mr. Boscher of Twickenham informs me that the specimens he has bred from caterpillars fed on the willow have been all far below the average size. The caterpillar is thorny, and of a tawny colour, broadly striped with black along each side.