ECONOMIC ENTOMOLOCr. 83 



platform to examine them more carefully. This led to 

 conversation rather than discussion, but from which the following 

 information was gleaned : 



Twelve years ago when Professor Southwick assumed charge of 

 the entomological work in the parks of New York City, large 

 numbers of trees were defoliated by the Bag Worm ( Thyridopteryx 

 ephemerceforynis) . The trees looked as if a fire had swept through 

 them, so completely were their leaves eaten by this insect. With 

 his improved tools, made for this work, he collected nearly twenty- 

 two bushels of these insects in one season and destroyed them. 

 This method of dealing with them nearly extirpated the species 

 and it has since been easy to keep them in subjection. This was 

 done when the trees were leafless, and the insects' cases were 

 easily seen. The Elm Leaf Beetle {Oaleruca xanthome} cBna) 

 works on the leaves of the elm tree, the beetles eating round 

 holes in the leaves and the larvae consuming every vestige of the 

 parenchyma. Professor Southwick said that in May and June he 

 constantly watched the elm trees in the parks, and as soon as he 

 saw the beetles or larvfe at work he immediately sprayed the parts 

 affected, but did not attempt to spray the whole tree at that time. 

 From the middle of May to October the trees were sprayed 

 several times. The solution used was : London purple, one 

 pound ; flour, four or five quarts ; lime, three pounds ; and water, 

 one hundred gallons. The flour is added to make the poison 

 adhere to the foliage. The solution is sprayed on the under side 

 of the leaves as much as possible, from a fine cyclone nozzle. 

 This solution is carried from the force pump to the nozzle, through 

 a quarter-inch orifice, rubber canvas insertion hose. The canvas 

 makes the hose strong and light, so that when it is lashed to a 

 light bamboo pole, the operator can hold up fifty or more 

 feet of it without difficulty. Professor Southwick urged that the 

 larvae of the Elm Beetle should be destroyed when they come 

 down the trunks of the trees to pupate at its base, as this 

 would materially lessen the number of beetles for the next gener- 

 ation. In the case of large trees, the men climb into them, but if 

 they are not over fifty feet in height, an extension pole is used to 

 raise or lower the spray as is needed. These poles are fastened 

 to each other with bands and are hoisted up and let down with a 

 rope and pulley. The preparation used for destroying the larvae 

 and pupae at the base of the tree is : Soap, six pounds ; kerosene, 



