102 OANKEB-WORM. 



gray color is produced by short black hairs and scales, on a whitish 

 ground. The thorax is hoary, usually with a distinct transverse black 

 line or narrow band. Some individuals have a distinct black dorsal 

 stripe extending the length of the body, but this is usually interrupted, 

 and often obsolete or wanting. Their general color is so similar to that 

 of the bark of the apple tree that they are easily overlooked, when not 

 in motion. The proboscis is obsolete in both sexes ; and these insects 

 take no food in their imago state. 



THE NATURAL HISTOEY 



of these insects may be briefly stated as followe : The female de- 

 posits her eggs upon various trees, but mostly upon the apple-tree 

 and the elm. These eggs hatch in the latter part of April or beginning 

 of May, or at about the time of the flowering of the red currant — the 

 time varying a week or two, according to latitude and the character of 

 the season. The caterpillars feed upon the foliage, and are often so 

 numerous as to defoliate whole orchards of apple-trees or whole parks 

 of elms. They attain their full growth in about one month, when they 

 let themselves down by a thread, and burrow from two to six inches 

 into the groond. Here they assume the chrysalis state, and remain^ 

 with a few exceptions, through the winter and until the first mild 

 weather of spring releases them, by removing the snow and frost from 

 the surface. They immediately make their way to the nearest tree^ 

 and crawl up its trunk. The winged males are now seen fluttering 

 about the wingless females, and, after pairing, the females deposit Ihtir 

 eggs and perish, thus completing the circle of their existence. 



RECORD OF 1871. 



I will introduce the practical treatment of this subject by a condensed 

 record of my observations upon this insect, during the spring and sum- 

 mer of 1&71. Such records, if carefully made, often pc ssess an intrin- 

 sic value, inasmuch as they present the actual facts and observations 

 upon which the opinions of the author are founded, and from wljich 

 others also can draw their own inferences, and we sometimes find it 

 convenient to refer to them for purposes which the author did not con- 

 template. 



In the summer of 1870 my attention was called to a small orchard 

 of apple trees, within less than a mile from my residence, which had 

 been stript of its leaves by some kind of caterpillar. Upon visiting ill 

 found the trees nearly bare of foliage, but not an insect could be found. 

 They had done their work of destruction and disappeared. I had no 



