THE STATE ENTOMOLOGIST. 123- 



surface of the ground, so that it is possible that this ladybird only 

 attacks them when it can get at them above ground; though, judging 

 from analogy, I strongly suspect it also seeks them out in their finder- 

 ground quarters. 



Artificial Remedies.— The best mode to get rid of the Apple root 

 Plant-louse is to drench the roots of the infested tree with hot water. 

 But to render this process effectual, the water must be applied in 

 quantities large enough to penetrate to every part of the infested 

 roots. There need be no fear of any injurious result from such an ap- 

 plication of hot water; for it is a very general rule that vegetable or- 

 ganisms can, for a short time, stand a much higher temperature than 

 animal organisms, without any injury to their tissues. In laying bare 

 the roots for the better application of the water, a sharp eye should 

 be kept for the friends above described, and when espied they should 

 be tenderly laid aside till after the slaughter of the enemy. Mulching 

 around the infested trees has been found, by Mr. E. A. Riehl and 

 others, of Alton, Illinois, to have the effect of bringing the lice to the 

 surface of the ground, where they can be more easily reached by the 

 hot water. 



THE WOOLY ELM-TREE WVSE—Eriosoma vlmi, N. Sp. 

 (Homoptera Aphidae.) 



The White elm is subject to the attacks of a woolly plant-louse 

 belonging to the very same genus as the preceding. This insect ap- 

 pears to be quite common in our State as well as in Illinois, for I have 

 known several elm-trees on Van Buren street in the city of Chicago,. 

 to be killed by it, and every tree of this description, around the court 

 house in St. Louis was more or less affected with it last summer. 

 The lice congregate in clusters on the limbs and the trunks, and cause 

 a knotty unnatural growth of the wood, somewhat similar to the 

 knots produced on the roots of the apple-tree by the other species. 

 They are mostly found sunk in between the crevices formed by these 

 knots, and the punctures of their little beaks cause the sap to exude 

 in the shape of little silvery globules, which may generally be found 

 dispersed among the knots. The down or wooly matter is secreted 

 by them from all parts of the body, but especially from the posterior 

 part of the back. It is of an intense white color, and is secreted ia 

 such profusion that it usually covers and hides the lice, and when they 

 are numerous, gives the limbs from a distance the appearance of 

 being covered with snow. They make their appearance during the lat- 

 ter part of May, and by the latter part of June the winged individu- 

 als may be found mixed up with the larvae and pupa?. I have experi- 

 mentally found that a washing with a weak solution of cresylic acid 

 soap will kill them all instantly, and they are thus easily exterminated. 

 They are also preyed upon unmercifully by the larv£e of an unde- 

 scribed species of Lacewing fly (Chrysopa eriosoma- of my MS,), 



