50 THE BUTTERFLIES OF THE BRITISH ISLES. 



In rearing this species from eggs laid in the autumn, a fairly 

 dry treatment appears to be the best. Protect the young cater- 

 pillars from frost, and do not water the plants during the winter. 

 When they become active again, about February, transfer them 

 to other growing plants, which should be kept ready for the 

 change. Do not water the plants much, or wet the foliage 

 at all, and keep a sharp look-out for earwigs. 



It seems pretty clear that this species passes the winter as a 

 caterpillar, and from the evidence available it appears equally 

 certain that the caterpillars would not survive an ordinary 

 winter in this country. Possibly, however, in very mild winters, 

 or in certain warm nooks on the south coast, some may be able 

 to exist until the spring, and then complete their growth and 

 reach the butterfly state. In such native-born butterflies the 

 ancestral migratory habit may be lost, owing to climate, and 

 they would not, therefore, wander far from the spot where they 

 emerged from the chrysalis, but found a colony, which probably 

 would be cleared off sooner or later by the severity of an English 

 winter. 



The Pale Clouded Yellow was not mentioned as an English 

 butterfly until Lewin wrote about it in 1795. He states that he 

 only met with it " in the Isle of Sheppey and on a hilly pasture- 

 field near Ospringe in Kent." He seems to have noted it in 

 different years at both places. Stephens, in 1827, referred to 

 it as a rare British species, and from that date until 1867 it 

 seems to have been common only in 183$, 1842, 1857, and 1858- 

 In 1868 it was abundant in the southern and eastern counties, 

 and was observed as far north as Lancashire and Yorkshire, 

 also in Ireland. It was common on the south coast in 1872, 

 and rather more so in 1875, when it spread into Essex and 

 Suffolk, and also inland. Until 1875 the butterflies seem only 

 to have been noticed in the autumnal months, but in that year 

 specimens had been seen in May and June. In 1876 the 

 species was pretty plentiful, but after that date it did not again 



