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were on the north-east coast, in the neighbourhood of 

 Cromer, in the exact line of migration taken by so many 

 species of birds. As the records came in from various 

 districts, it was found that the insects spread first through 

 Norfolk and adjoining counties, going steadily further west, 

 until in about a week notices came from Herefordshire, 

 Worcestershire, and also from districts northward and south- 

 ward extending over the whole kingdom. He said that 

 Mr. Adkin had already touched upon the abundance and 

 disappearance of C. edusa and V. cardui ; it had been noticed 

 that the larvse resulting from an unusual abundance of either of 

 these species, fed exceedingly late in the season, and after 

 the pupal change frequently died in the winter. Probably 

 in warmer countries the species emerged earlier than with us, 

 and after arriving here there was not sufficient time for a 

 second brood to come to maturity. He remembered on one 

 occasion attempting to rear some Deiopeia pulchella, L., from 

 the South of France ; the larvae were fed in the sunshine, and 

 were feeding up rapidly, and one had become full-fed and 

 had spun up, when the weather turned wet and dull, and the 

 remainder of the larvae refused to feed, and died. Mr. 

 Carrington remarked that Mr. Barrett had made a very 

 valuable suggestion, when he stated that the females of 

 an immigrating species had not sufficient time to reproduce 

 their kind in the manner which was usual with individuals 

 of the same species inhabiting this country. That the 

 evidence as to birds invariably following certain lines, was 

 conclusive from the observations made by ornithologists, but 

 with regard to insects he thought it was extremely fragmentary, 

 and a good deal more attention would have to be paid to 

 insects before it could be accepted as finally settled that 

 insects in immigration followed the same lines as birds. 

 Mr. Barrett observed that it would be impossible to get the 

 same evidence with regard to insects as was obtainable in- the 

 case of birds. Mr. Adkin, in reply, said that it was quite 

 true as Mr. Barrett stated, that there was good reason tor 

 supposing that the migrations of Lepidoptera followed the 

 same tracks as those of birds, and he fully believed that it 

 would ultimately be proved that they did so. Although he 

 was unable at present to produce any conclusive evidence, 

 he thought the general bearing of what he had submitted, 

 taken as a whole, pointed very strongly to such a supposition 

 being correct. 



