1822 ARBORETUM AND FRUTICLTUM. PART III. 



a red headland about Hin. 

 long. In this state it con- 

 tinues four years, during 

 which time it commits the 

 most destructive ravages on 

 the roots, not only of grass, 

 but of all other plants and 



young trees. When full )/ jC^H 



grown, the \ar\vc dig in the 

 earth to the almost incredible depth of 5 ft. or 6 ft., spin a smooth case, 

 and then change into a chrysalis. In this state they remain till the fol- 

 lowing spring, when the perfect insect comes from the ground, and com- 

 mences an immediate attack on the leaves of trees ; and, according to 

 Salisbury, the leaves of the oaks in Richmond Park were, during one sum- 

 mer, so eaten by it, that scarcely an entire leaf was left. The most remarkable 

 account of the ravages of these insects is, however, given by Molyneux, in 

 one of the early volumes of the Philosophical Transactions^ in which their ap- 

 pearance in the county of Galway, in Ireland, in 1688, is narrated. They 

 were seen in the day-time perfectly quiet, and hanging from the boughs' in 

 clusters of thousands, clinging to each other like bees when they swarm ; but 

 dispersing towards sunset, with a strange humming noise, like the beating of 

 distant drums ; and in such vast numbers, that they darkened the air for the 

 space of two or three miles square ; and the noise they made in devouring the 

 leaves was so great, as to resemble the distant sawing of timber. In a very 

 short time the leaves of all the forest trees, for some miles were destroyed, 

 leaving the trees as bare and desolate in the middle of summer as they would 

 have been in winter : they also entered the gardens, and attacked the fruit 

 trees in the same manner. Their multitudes spread so exceedingly, that they 

 infested houses, and became extremely offensive and troublesome. They were 

 greedily devoured by the swine and poultry, which watched under the trees 

 for their falling, and became fat on this unusual food : even the people adopted 

 a mode of dressing them, and used them as food. Towards the end of the 

 summer they disappeared suddenly, and no traces were perceived of them the 

 ensuing year. (P/iil. Trans., xix. p. 743., &c.) About the middle of the last 

 century, 80 bushels of these beetles were gathered on one farm near Norwich. 

 (See Encyc. of Agri., ed. 2., p. 1116.) The best method of destro}'ing these 

 insects is to shake the branches on which they hang at noonday, when they 

 are in a state of stupor, and then to sweep them up and carry them away; or, 

 torches may be held under the trees, which will stupify the beetles, and 

 occasion them to fall. Birds are very useful in destroying these noxious insects. 

 In the Magazine of Natural Histori/, vol. v. p. 65., a story is told of a gentle- 

 man, who, finding his oak trees stripped of their leaves in the middle of sum- 

 mer, suspected some rooks of having destroyed them. "That the oaks were 

 nearly bare was beyond dispute ; and he had himself seen the rooks settling 

 on them, and pecking away right and left with their bills. War was therefore 

 declared against the rooks; but, fortunately, before hostilities were commenced, 

 the gentlemen was convinced, by some one who knew more of natural history 

 than himself, that the rooks were not in fault : on the contrary, they had only 

 flocked to the trees for the sake of devouring the myriads of cockchafers, anil 

 of the larva; of moths, which were the real depredators." Blackbirds act in 

 the same manner ; and the Rev. W. T. Bree relates an instance of these birds 

 stocking up the grass to find the larvae of the cockchafer, in a garden where 

 there was plenty of ripe fruit. (See Mag. Xaf.JIist.,\ol. vi. p. 518.) The leaves 

 are also devoured by the larvJE of one of the species of flea weevil (Orch^stes 

 quercus). A'grilus viridis, Cryptorhyncus qucrcus, and Acalles roboris are also 

 coleopterous insects found among the leaves of the oak. Aleyrodes proletella, 

 a minute but very interesting homopterous insect, also feeds upon the leaves 

 of the oak. (licaumiir, Alcmoires, tom.ii. pi. 25.) 



The young Stems and liuds of the Oak are also infested by various species of 



i 



