19fe 



'detail, occur from July to the third week in October, when pupation 

 generally takes place. The pupae are to be found on the ground 

 attached to fallen leaves, low bushes and shrubs ; sometimes, though 

 rarely, on branches. On the Continent of Europe, this pest specially 

 attacks beeches, though a long hst is given of deciduous trees and 

 shrubs which are attacked when beech leaves are wanting. The cater- 

 pillars have even been known to attack fir, larch and pine, while ash 

 and alder are apparently distasteful. Failure of food hastens the date 

 of pupation and reduces the size of the imago. 



The caterpillars of D. pudibunda are greatly influenced by cold, 

 wet weather, and in some years large numbers are thus killed ; many 

 fall victims to early night frosts, so that out of the three or four 

 hundred eggs laid by each female, the number of the surviving cater- 

 pillars rarely amounts to a plague ; this only occurs when the weather 

 conditions in late summer are favourable. If the weather be for a 

 time not only warm but damp, the mortality from bacterial and fungus 

 diseases is very great. Numbers were found at Elspeet dead of 

 " flacherie " on 6th October. Large numbers of the pupae are attacked 

 by a fungus, Isaria desa or Cordiceps militaris, and the following 

 parasitic Hymenoptera have been bred from them : the Ichneumons, 

 Pimpla instigator, P. pudibundae, Ichneumon hartigi, I. midticinctus, 

 and Anomalon excavatum, and the Proctotrupid, Cemphronal bipes. The 

 eggs are also infested by the larvae of the Scelionid, Telenomus 

 truncatus, Nees, {Teleas zefferstedti, Ratz.). These parasites, as well 

 as the fungi, generally make their appearance in force when the cater- 

 pillars are very numerous. Various predaceous animals also greatly 

 reduce the numbers ; the eggs are devoured by nuthatches, tits and 

 other birds ; cuckoos, jays and tits eat the caterpillars ; and the pupae 

 are devoured in winter by crows, rooks, magpies and tits , and also 

 by bark-beetles, and even wild pigs are to be regarded as useful in 

 consuming the pupae of Dasychira and other Lepidoptera. The 

 damage done by the caterpillars is not so great as might be expected 

 from their enormous numbers. The first signs of defoliation are 

 generally visible in the second half of July and in August, that is to 

 . say, at a time when the leaves have already to a large extent performed 

 their functions, so that the growth is not greatly interfered with. 

 The attack comes so late that the buds formed in the same year, even 

 ■on thoroughly defoliated trees, often open and the effect is thus different 

 from that resulting from the attacks of Melolontha, Lymantria dispar, 

 Euproctis chrysorrhoea, Malacosoma neustria, etc. It has been observed 

 that when a beech has been defoliated by Dasychira, the buds open 

 about eight days earlier in the following spring ; the foliage is however 

 less and the amount of beech mast produced is very small. When 

 one attack follows another for two or three years in succession, the 

 beeches suffer seriously in their growth and the whole of the crown of 

 a tree may die. The total defoliation of the trees causes a loss of 

 vegetable manure to the soil below, though the excrement of the cater- 

 pillars often forms a layer on the ground and encourages a gro\\i:h of 

 grass which may last two or three years, and this is especially injurious 

 in nurseries of one or two year old trees. The hairs of the cater- 

 pillars are carried by the wind and cause great annoyance and itching 

 to human beings, and produce lung and liver troubles in cattle, some- 

 times causing death. 



