100 [October, 



ON THE HYPONOMEUTA OF THE APPLE. 

 BT CHAS. G. BAERETT, T.E.S. 



The apple trees on this side of London have been terribly in- 

 fested this year with the larva of a Hyponomeuta, which ought to be 

 the continental malineUus, but is here held to be merely a form of 

 the common padellus. I obtained some larvae and a large number of 

 pupae from apple trees at the end of June. The larvae were about the 

 size of those of cognatellus, dark greenish, with the usual conspicuous 

 black spots, spinning webs in the usual loose fashion of the genus 

 among the apple leaves. The pupae w^ere spun up in little clusters of 

 cocoons, laid closely side by side in the hollows of curled-down apple 

 leaves, and were, therefore, very easily collected from the trees. 



A few days later, I found ordinary larvae and pupae of padellus 

 in a hawthorn hedge, the larvae smaller and darker than those on 

 apple, and the pupae in cocoons suspended upright, and singly, in the 

 loose silken web. 



The moths from apple began to appear on July 8th, and came out 

 rapidly, most of them having emerged by the 15th, on which day the 

 first of those from hawthorn appeared. 



Nearly all the moths from the apple-pupae were larger than those 

 from hawthorn, and their tendency is decidedly to a lighter colouring, 

 but while some of them are of as clear a silvery white as cognatellus, 

 the great majority are clouded more or less with grey, and some are 

 entirely grey, being of the precise shade of colour of the normal form 

 from hawthorn, which varies in the opposite direction ; the majority 

 being unicolorous grey, but many specimens clouded with silvery- 

 white, and occasionally a specimen is entirely of the latter colour. 



The dots in the two forms are identical in position, both on the 

 thorax and the fore-wings, and vary in number in the same manner, 

 except that in the apple-form the majority have a cluster of small 

 dots, composed of two irregular lines, towards the apex of the fore- 

 wings, and the minority have but a single row, while in the hawthorn 

 feeder the majority have but the single row and the minority the 

 cluster. Both agree in the white colour of the head and the uni- 

 colorous dark hind-wings. 



Thus it appears that the two forms differ in the larva, the mode 

 of pupating, the time of appearance, and to some extent in the 

 colouring of the imagines. Yet there seems to be no reliable 

 character by which the latter can be separated — indeed, I am very 

 sure that when mixed together it would be impossible to separate 



