No. 4.] SHADE-TREE INSECT PROBLEM. 83 



honors with the willows and poplars as the characteristic 

 tree of our river valleys and seaboard. This abundance of 

 elms along our streams long ago defined the areas in which 

 the beetle etui breed to the best advantage, and where it will 

 doubtless become a permanent resident. The swarms of 

 beetles which invaded this State from the south by way of 

 the Housatonic and Connecticut valleys have passed north- 

 erlv into southern Vermont and New Hampshire, while 

 lateral swarms have ascended the valleys of the Westfield, 

 Deerfield and Ware rivers. Another invasion of a later 

 date has occurred along the line of the Blackstone River. 

 The beetle has also worked eastward around the coast and 

 ii}) the Merrimac River to Haverhill, Lawrence and Lowell. 

 The main lines of railroads probably have contributed in no 

 small degree to the diffusion of the beetle, which with the 

 approach of cold weather frequently enters freight cars for 

 the purpose of hibernation. Finally, the compact plantings 

 of elms in the centres of our towns and cities have given the 

 insect the best kind of an opportunity to develop as a local 

 pest. 



The life history of this insect is similar to that of other 

 members of the great family Chrysomelidoe. The beetles 

 hibernate in large numbers in sheltered localities, under 

 roofs, shingles, clapboards and in empty buildings. As 

 soon as the warm weather starts the buds of the elm, these 

 beetles emerge and feed greedily upon the young leaves, 

 which soon become perforated as if by charges of fine shot. 

 After feeding for a week or ten days, egg-laying is com- 

 menced, and by this time the leaves are nearly developed. 

 The beetle feeds and lays alternately over a period of several 

 weeks. Two female beetles observed by Dr. E. P. Felt for 

 four weeks laid respectively 431 and 623 eggs. Because of 

 the similarity, any one familiar with the eggs of the potato 

 beetle will readily recognize those of the insect under dis- 

 cussion. The yellow, spindle-shaped eggs of the elm-leaf 

 beetle are laid in small compact masses on the under surface 

 of the leaf. In a week's time the eggs hatch and the young 

 larvae commence feeding upon the tender foliage. 



While the damage caused by the feeding of the mature 



