Nectar From Bark and Plant Lice. 333 



I have described this insect (Fig. 140) under the name 

 of Lecanium Tulipifera. In 1870 it did no small injury 

 to our tulip trees here at the college. It has seriously in- 

 jured this tree in the states bordering the Ohio river. The 

 tulip is often called poplar, which is quite incorrect. The 

 poplar belongs to the willow family, the tulip to the mag- 

 nolia. This louse is of double interest to bee-keepers. It 

 ruins one of our best honey trees, and supplies a poor sub- 

 stitute for plant nectar to the bees. All bark lide, which 

 include the orange tree scale lice of the south, are best 

 destroyed by use of kerosene oil. This latter is best ap- 

 plied in the form of an emulsion, with soap. To make 

 the kerosene and soap emulsion I make a very strong suds, 

 using one-fourth pound of whale oil soap, or one quart of 

 soft soap, and two or three quarts of water. To this is 

 added one pint of kerosene oil and all churned by use of a 

 force pump till it is thoroughly and permanently mixed. 

 I then dilute with water till the kerosene oil forms one- 

 fifteenth of the whole. Whitman's fountain pump is admi- 

 rable for making such applications. 



I have also seen the bees thick about several species of 

 plant lice. One, the Erisoma imbricator. Fitch, works on 

 the beech tree. Its abdomen is thickly covered with long 

 wool, and it makes a comical show as it wags this up and 

 down upon the least disturbance. The leaves of trees 

 attacked by this louse, as also those beneath the trees, are 

 fairly gummed with a sweetish substance. I have found 

 that the bees avoid this substance, except at times of extreme 

 drouth and long protracted absence of honeyed bloom. 



Another species, Thalaxes ulmicola gives rise to certain 

 solitary galls, which appear on the upper surface of the 

 leaves'of the red elm. These galls are hollow, with a thin 

 skin, and within the hollows are the lice, which secrete an 

 abundant sweet that often attracts the bees to a feast of fat 

 things, as the gall is torn apart, or cracks open, so that the 

 sweet exudes. This sweet is anything but disagreeable, 

 and may not be unwholesome to the bees. The larch 

 louse, Lachnus laricis, secretes a liquid that is greedilv 

 taken by the bees. 



Another of the aphides, of a black hue, works on the 



