INJURIOUS INSECTS, FUNGOUS DISEASES, ETC. 167 



mass will soak in and kill the eggs. The following prepara- 

 tion was used in the work against the gipsy moth in Massa- 

 chusetts: Creosote oil, 50 per cent., carbolic acid, 20 per 

 cent., spirits of turpentine, 20 per cent., and coal-tar 10 per 

 cent. The last was added to color the compound and thus 

 show at a glance what clusters had been treated. 



Advantage may be taken of the migrating habit of the 

 caterpillar during the daytime by tying burlap bands around 

 the tree-trunks and then turning down the upper portion 

 of the burlap over the string. The bands can be lifted 

 daily and the caterpillars beneath killed. 



The larva is quite resistant to arsenical poison, and it 

 requires a large dose to kill it. Arsenate of lead should be 

 used as soon as the leaves are well grown, as the young cat- 

 erpillars are most susceptible to the insecticide. 



Brown Tail Moth {Euproctis chrysorrhcea Linn.). The 

 brown tail moth is the other species that has been in- 

 troduced into Massachusetts within recent years and is 

 scarcely second to the gipsy moth in destructiveness. 

 About the middle of July the moths are on the wing, and 

 each female lays from two hundred to three hundred eggs 

 in an oblong cluster on the under side of the leaf, near the 

 end of a branch, covering them with a dense mass of brown 

 hair. The eggs hatch early in August. While still young 

 the caterpillars make a nest in which they hibernate during 

 the winter. This is constructed at the ends of the twigs and 

 made by drawing together a few leaves, lining them with 

 silk and surrounding them with a mass of silken threads. 

 The tents are so firmly secured to the twigs that they can 

 be removed only with considerable force. 



The young caterpillars cease feeding and retire into these 

 tents late in September, and there they remain during the 



