FSYCHE. 



THE INFLUENCE OF METEOROLOGICAL COXDITIOXS OX 



IXSECT LIFE. 



BY CHARLES GOLDIXf; BARRETT, PEMBROKE, WALES. 



[Abstract, by B: Pickman Mann, Wasbington, D. C-. from Entoni. mo. mag.. June iSSj, 



V. 19. p. i-S.] 



'•The means employed by nature to a dozen of the hiryae sei'med to possess 



keep species within due bounds — check- sufficient yitality to feed. These were 



ing their inordinate increase or unnec- fetl on potted phxnts, grown in a sunny 



essarv decrease — are so certain and window, wliere they, covered witli 



reliable in their residts, and yet so gauze, ••grew rapidly, feeding with es- 



obscure and difficult to trace in their pecial eagerness when the sun was shi- 



modes of action, that almost any obser- ning on them. The weather happened to 



vations, however slight, which seem to be fine and the sun hot for two or three 



be reliable as data from which to ascer- 

 tain these means, are interesting and 

 worthy of being put on record. 



'• In every district and eyery climate 

 there are evidently manv species so 



weeks just at that time, and one larva 

 made such progress that in a fortnight it 

 was full-fed, when it spun a very slight 

 cocoon on the gauze and turned safely 

 to pupa. By this time tyvo more larvae 



peculiarly fitted to it that none of the were full-fed and left the food-plant for 

 periodical changes of weather and the gauze, the rest being fully half- 

 temperature materially aflect their num- grown, when a change of weather 

 hers, and from these little evidence can came, with wind, heavy rain, and a 

 be obtained. It is from those species total absence of sunshine. The lar\ae 

 which onlv casually and rarely extend were, of course, not e.xposed to the 

 themselves from their natural homes rain, but the etiect of the change 

 into climates unsuitable for them, or was that those full-fed made no attempt 

 from those which are alwa\s to be to spin up, and the rest ceased to feed, 

 found in a given locality, but sometimes and in a few days they all fi'll oft" the 

 rareh and always varying in numbers, gauze or the plants, dead. Aftei a 



that the most satisfactory evidence must 

 l)e expected. 



" In the first class of cases an exam- 

 ple occurred to me a few years ago 

 which seems very much to the point." 



From eggs of Deiopeia pulchella 

 received from the south of France some 

 moths were, by great care and assiduity, 

 reared to maturity in England, and 

 from these were olitained fertile eggs, 

 wiiich did\- hatched. Only about half 



fortnight of yvet weather it cleared up 

 and the one pupa produced the moth — 

 a male. 



'• This seems to supply a key to the 

 whole history of the eccentric casual 

 appearances" in England. " of this and 

 manv other inhabitants of warmer 

 climates. In nbedience to some sin- 

 gular instinct that impels insects when 

 becoming too numerous in their natural 

 homes to emigrate to ' fresh fields and 



