THE ELM-LEAF BEETLE IN NEW YORK STATE 15 



numerous secure crevices in which the final changes may be 

 effected. At this time the trunks of infested trees present an 

 interesting sight as thousands of the grubs crawl up and down 

 the shaggy bark. Occasionally their numbers are so great as to 

 give a distinct character to the surface they are moving over, 

 presenting a peculiar grayish yellow mass of motion enlivened 

 here and there with an orange yellow pupa. A few days later 

 the light yellow pupae are more numerous on the trunk and 

 around the base of the tree and adjacent shelter, where they 

 may be found in golden layers nearly an inch in depth inter- 

 spersed here and there with a dark larva. It will be found that 

 many larvae do not descend the older trees but take refuge in 

 the crevices of the bark, or, if there are overhanging limbs, they 

 may drop in numbers from the tips of the branches. Many are 

 content to transform in the gutters, others seek shelter in the 

 crevices of the sidewalks and large numbers cross wide spaces 

 and pile themselves up against a wall, fence or around any shel- 

 tering bush or weed. 



SPECIES OF EliMS ATTACKED 



It will be observed in most localities that the American elm, 

 Ulmus Americana, is comparatively exempt from the attacks of 

 this insect. Sometimes the beetles will make their way from 

 adjacent European elms and seriously injure the American spe- 

 cies and, after they have once become established, the but par- 

 tially migratory habit of the beetle ensures attack for a few 

 successive seasons at least. In most cases the English elm, 

 Ulmus campestris, and the Scotch elm, Ulmus montana, suffer most 

 seriously from the pest, while our native species are but little 

 affected. This was very noticeable in Troy and Lansingburg. 

 In the former, European elms are numerous and the work of the 

 elm-leaf beetle is conspicuous over a greater part of the city, but 

 as one proceeds northward into Lansingburg the American elms 

 abound almost to the exclusion of the foreign species and evi- 

 dences of this pest are comparatively rare. Again, in 1895 the 

 American elms of Albany showed very little injury by the insect. 



