THE yOUNG 



NATUEALIST. 



383 



Varieties. — Extreme varieties are not 

 rare. Fig. 2 is from my own collection- 

 Figs. 3, 4, and 5 are from specimens in Mr. 

 C. S. Gregson's collection. Sometimes the 

 red-brown spots are collected into a large 

 brown patch at the large end. I have seen 

 one with the ground colour nearly white. 

 Others are recorded of a uniform pale blue 

 resembling those of the thrush, without 

 spots. Mr. Doubleday noticed that most 

 of the blackbirds in one part of Epping 

 Forest laid blue eggs. 



ECONOMIC ENTOMOLOGY. 



By S. L. MosLEY. 

 {Continued from page 375.) 



VII.— Insects injurious to Forest 

 Trees. 



Ash. ■ — AsH-BARK Beetle (Hylesiniis 

 fraxini). — This beetle and its larva injure 

 ash-trees, sometimes to a considerable ex- 

 tent, by boring galleries between the wood 

 and bark. 



Remedies. -Remove all decaying branches, 

 keep the trees as healthy as possible, and if 

 small holes like shot-holes be observed in 

 the bark, stop them up by giving a coating 

 of soft soap. 



Elm. — Elm-bark Beetle (Scolytus dis- 

 tructorj, — This beetle injures elm in the 

 same way as that on ash. 



Remedies. — Never allow felled trunks to 

 remain about with the bark on. When a 

 :ree is badly attacked, it has been found of 

 jervice to pare off the outer bark and brush 

 )n a mixture of lime and cow-dung. 



I Oak — Cockchafer {Melolontha vulgaris). 

 This and a smaller species is sometimes 

 injurious in the larva state to roots of young 

 rees and other crops, but does not often 

 xist in sufficient quantities to be of great 

 njury. 



Remedies. — In gardens, digging up the 

 :rubs and destroying them ; and on farms, 



all birds which follow the plough, such as 

 rooks and gulls, should be encouraged. 



Galls. — A large number of galls may be 

 found on the oak, but it is questionable if 

 they have any great deteriorating effect 

 upon the trees. 



The Pea-green Moth {Tortrix viridana) , 

 and the larvae of several geometers of the 

 genus Hybernia, &c., sometimes entirely 

 strip the oak-trees of their leaves. 



Remedies.— The encouragement of all 

 insectivorous birds should be encouraged. 

 Thrashing the boughs over a sheet or in- 

 verted umbrella will also dislodge a great 

 many. 



Pine. — Pine Beetle {Hylurgus piniper- 

 da). — This beetle injures young trees by 

 boring tunnels up the centre of young shoots, 

 and also by mining between the wood and 

 bark. 



Remedies. — Clearing the ground of all 

 loose branches or bark ; nipping off infested 

 branches and burning them. 



Several species of Tortrices also injure 

 young pine in a similar way by eating the 

 young shoots, and no better plan of remov- 

 ing them seems to be known than hand- 

 picking. 



Sirex Gigas. — The larva of this large fly 

 bores galleries into the solid wood of pine 

 and fir, but seldom appears in sufficient 

 numbers to cause any alarm. 



Remedies. — When a tree is found to be 

 badly infested, the best plan is to cut it 

 down and cut up the timber at once, des- 

 troying the grubs inside. 



Poplar. — Hornet Clearwing {Sesia 

 hemheciformis) . — The larva of this insect is 

 very destructive to poplars in some districts, 

 boring into the solid wood. 



Remedies. — The best plan is to look for 

 the newly-emerged moths on the trunks 

 early in the morning in July, and also for 

 any brown eggs that may have been de- 

 posited on the bark. 



{To bs contimied) 



