THE YOUNG NATURALIST. 



235 



ing fruit-trees in several places), though partial to hawthorn and lime, it is 

 also of a roving turn, and frequently travels from tree to tree. By rearing a 

 good many larvse of 0. gonostigma I came to the conclusion that the species 

 in its larval stage is rather nervous, if the word is admissible, at least any 

 noise, or the shaking caused by the wind, soon startles them from their food. 

 When very young, they often fall to the ground therefore, and have difficulty 

 in getting back to the bushes before their strength is exhausted. It was un- 

 fortunate indeed for this species, that the ground close t© its habitat should 

 be taken for the rifle practice of volunteers. Another circumstance that tells 

 against its increase is the hybernation of the larva, and it is not protected by 

 any social or solitary web, but simply reposses on the twigs near the earth 

 through the winter, when many die in damp seasons. The number of the 

 eggs, however, is much greater than in 0. antiqua, which species winters in 

 the egg state. Probably both species in warmer climates are double-brooded ; 

 0. gonostigma can be made so in confinement. Perhaps some London col- 

 lector can tell us whether Wimbledon Common still yields this species, I know 

 the frequent popping on shooting days was far from favourable to the increase 

 of some of the choice Lepidoptera that used to occur between the Common 

 and Croombe Wood. I might add that the female goriostigma very dexter- 

 ously denude their bodies, while egg-laying, of the thick down that clothes 

 them, using it as a nidus for the eggs, though it appears odd they should do 

 this, since the larvae hatch out in two or three weeks. — J. E. S. Clifford, 

 Gravesend. 



A Plague of Plies. — Hearing reports of " a plague of flies," so-called, 

 which were much annoying the rustics of some of North Kent villages, by 

 entering the eyes,, noses, and mouths of persons working in the open air, I 

 went to see, and found, as I suspected, a late migration of Aphides was going 

 on. The examples I took chiefly belonged to a large black species, and they 

 were travelling westward in goodly numbers. It was thought by the late 

 Prancis Walker, that these Aphis journeys were seldom for any distance, but 

 I had proof in a summer migration last year, that a host of individuals started 

 from the fields of Essex, crossed a line of marsh, then the Thames, and the 

 town of Gravesend and its adjacent gardens, to spread themselves over the 

 hop grounds. Many died en route, doubtless, those, however, that reached 

 their destination must have travelled three or four miles. No doubt this 

 October exodus was prompted by the long continued dry weather, and the 

 fact that after a dry's rain there were still Aphides journeying suggested that 

 these had come some distance. 



Many journals have remarked, that the common housefly has been un- 



