58 THE BUTTERFLIES OF THE BRITISH ISLES. 



The chrysalis is whitish, more or less tinged with green, but 

 having the oblique lines on the sides whitish ; the veins of the 

 wings also show up whitish. 



The caterpillar was well known to entomologists in this 

 country as far back as 1758, when, in May, four were obtained 

 from sallow at Brentwood in Essex. It usually occurs on 

 sallow, but an instance is recorded of it refusing to eat this 

 plant ; it would probably have starved if willow, upon which it 

 fed up, had not been substituted. A full-grown caterpillar was 

 on one occasion found at Raindene in Sussex on poplar, which 

 is a well-known food of the species on the Continent. Now and 

 then a full-grown caterpillar has been met with in October, and 

 Buckler reared two in the autumn from the egg almost to the 

 chrysalis stage, but they died before the change was effected. 



As befits his rank, the Emperor has lofty habits, and after 

 quitting the clump of sallow bushes, among which its trans- 

 formations from egg to the perfect insect were effected, it 

 resorts to the oak trees, around which it flies in July, and, 

 when not so engaged, rests on a leaf of the higher branches. 

 To capture the butterfly, when seen at such times, is not 

 altogether an easy matter, as for the purpose the net must 

 be affixed to the end of a pole about 14 or 15 feet in length. 

 The insect's rather depraved taste for the juices of animal 

 matter, in a somewhat advanced stage of decay, is a fact well 

 known to the professional collector and others who have taken 

 advantage of it to the monarch's destruction. This method of 

 attracting a butterfly for the purpose of capture is, however, not 

 exactly to be commended. It surely is a greater pleasure to 

 show one's friends a single specimen that has been captured by 

 dexterity with the net, than to exhibit fifty that were secured 

 by a device which is not only unsavoury, but unsportsmanlike. 

 The female, however, is not to be allured ; she must be sought 

 among the sallows, and when seen is not easy to net, as she 

 skims away over the tops of the bushes and is difficult to follow. 



