1907.] Insect, Fungous and Other Pests. 



157 



To kill the mites that issue from eggs, therefore, a second 

 fumigation with sulphur should follow in ten days. 



Dust Beetles. — Some specimens of old oak timber forwarded 

 from Southampton during March were found to have been 

 attacked by one of the so-called " dust " beetles, the species 

 probably being Anobium tesselatum, one of the largest. This 

 beetle is 6 mm. or more in length, and is dark brown in colour 

 with yellowish or whitish pubescent patches or spots. It lays 

 its eggs in timber, and the grubs, on hatching out, continue 

 the tunnelling. The beetle is often termed the Death-watch, 

 owing to the ticking noise caused by the beetles striking the 

 wood with their hard jaws. This they do in order to attract one 

 another, but the noise has given rise to various superstitions. 

 A characteristic point in the work of these beetles is that the 

 actual exterior wood (save for the flight' holes of the adult 

 beetles) may not show the damage, which is internal, and the 

 damage may, therefore, remain unnoticed for a time. In mov- 

 able furniture the pest may be combated, but in a wide-spread 

 infestation, for instance, in a roof, treatment is difficult. If the 

 infestation is limited, infested planks should be removed and 

 burned. Where it is possible to run paraffin into the burrows 

 this treatment would kill both beetles and larvae. As a protective 

 measure against such beetles the wood may be painted (or, 

 better and surer still, impregnated) with corrosive sublimate 

 dissolved in methylated spirit, or copper vitriol, chloride of 

 zinc, or arsenious acid. If any of these are used it should be 

 noted that they are dangerous poisons. 



In dissecting the specimens of timber two beetles which act 

 as followers of Anobium were found, viz. : one called Crypto- 

 phagus and one Anthrenus. The former belongs to an obscure 

 family, the larvae having been found in both old wood and. 

 dried straw. The species of the genus Anthrenus possess the 

 characteristic of living on any dried material, such as old wood,, 

 furs, dried specimens of plants and animals, horse-hair in 

 furniture, &c. In the timber under notice the active agent 

 of destruction was Anobium tesselatum, Cryptophagus and 

 A nthrenus acting as scavengers. 



' Wasps. — The question of the harm done by wasps and the 

 desirability of their destruction has been raised by corre- 

 spondents in the Isle of Wight and Cambridge, one of whom. 



