INSECTS AFFECTING PARK AND WOODLAND TREES 533 



states that there are five or six generations annually in the vicinity of 

 Washington. He recommends the collecting and burning of infested 

 leaves before thcinsects escape. 



Fitch's oak leaf miner 



Lithocolletes fitchella Clem. 

 This species works in much the same way as the preceding, except that 

 its tentlike mines occur on the under surface of the leaves and are visi- 

 ble on both sides. Professor Comstock states that it is a very common 

 species on all kinds of oak at Washington and records the insect from 

 Kirkwood Mo. 



Walking stick 



Diapheromcra fcmorata Say 



Green or brown, sticklike insects sometimes measuring, exclusive of the antennae, 3 

 inches in length, are more or less abundant in forests of deciduous trees in early autumn. 



This peculiar insect is a rather common form, though it frequently 

 escapes observation because of its general resemblance to a stick. The 

 young are green and closely mimic the color of the surrounding foliage, 

 while the adults as they age and the foliage turns, change from the green 

 to brown and toward the end of the season mimic brown sticks. On this 

 account, in particular, specimens arouse considerable interest in the mind of 

 the finder, and requests for identification and a brief account of its life 

 history and habits are not infrequently made. 



Early history. This deliberate, slender insect appears perfectly harm- 

 less and as a rule it causes very little damage. Occasionally it becomes 

 excessively abundant and has been known to strip large areas. Prof. C. 

 V. Riley, in his report for the year 1878, gives several abstracts from pub- 

 lished reports of about that date, which are of considerable interest, par- 

 ticularly as they relate to depredations occurring in New York State and 

 vicinity. Mr G. C. Snow of Yates county N. Y., published in the New 

 York Weekly Tribune, Nov. 11, 1875, following: 



I noticed about August 15th, in a reservation of young timber, mostly 

 white oak and hickory, a few trees having the appearance of being burned 



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