14 



The substance to be used in these spraying operations may be Paris 

 green, London purple, or arsenate of lead. The directions for the use 

 of these substances have been so often repeated, that it is not worth 

 while to mention them here. 



The other remedy — the destruction of the descending larvae and the 

 quiescent pupae— is, as above stated, and must always be, incomplete. 

 The standard kerosene emulsion, diluted one part to five parts of 

 water, will destroy the insects in either of these stages. This has been 

 successfully used in several New England towns the past season, par- 

 ticularly in New Haven. It must be applied to the base of the trunk 

 and under the entire limb spread of the tree. The rough bark must 

 be removed to a slight extent (the writer does not advocate severe 

 scraping), leaving as few crevices as possible which may harbor the 

 pupating insects. If a tree is very large, it will pay occasionally to 

 climb into the main crotch and destroy such individuals as may have 

 collected at that point. Experience leads us to the estfmate that on 

 large trees not more than one-half to two-thirds of the larvae reach the 

 base of the trunk and transform at that point. The extent to which 

 larvEe drop from overhanging branches has been questioned, and it is 

 sometimes a difficult matter to decide. The city forester of Spring- 

 field, Mass., however, called our attention to a peculiar and eminently 

 satisfactory case where the drooping branches of a large elm extended 

 completely over a house on the other side of which there were no elm 

 trees. On the far side of the house, beneath the tips of the overhang- 

 ing branches, the larvae and pupae were collected in large numbers in 

 the summer of 1895. 



THE WHITE-MARKED TUSSOCK MOTH. 

 ( Orgyia leucoBtigma Smith and Abbot. ) 



Original home and present distribution. — This insect is a native of 

 North America. It ranges from Jacksonville, Fla., to Nova Scotia, 

 on the eastern coast, and extends west certainly as far as Keokuk, 

 Iowa, and probably farther, although the records at command include 

 no actual captures beyond this point.' It does not occur in California, 

 so far as learned. • 



Food plants. — It attacks almost every variety of shade, fruit, and 

 ornamental trees, with the exception of the conifers. In the city of 

 Washington it seems to select by preference the poplars, soft maples, 

 the elms, alders, and birches, as well as the willows. It is also found 

 here on apple, pear, cherry, plum, peach, other varieties of maple, 

 locust, box elder, ash, catalpa, rose, horse-chestnut, persimmon, syca- 

 more, mulberry, and a number of other trees. 



Life history and huh i,t>i. —This insect passes the winter in the egg 

 state. The overwintering eg^a are laid by the female moth in the latter 



' Prof. L. Bruner has since reported this species from Omaha and Lincoln, Nebr. 



