286 -NEW YORK STATE MUSEUM 



Description. The adult beetle is moderately robust, olive brown, and 

 is from s/j^ to nearly y< inch long. The general form of the insect is well 

 represented in the accompanying illustration. The white pupa is about y^ 

 inch in length, rather slender, and tapering to tip of the abdomen. The 

 grub or larva is nearly i^ inch in length, creamy white in color and with 

 dark mouth parts. It will be observed that the flattened head is only 

 slightly wider than the abdominal segments. The tip of the larva is armed 

 with a pair of linear, serrate chitinous bars. 



Distribution. The distribution of this insect as given by Mr Chitten- 

 den is as follows: Mt Washington, Boston, and Jamaica Plain Mass.; 

 Adirondacks, Elke Lake and elsewhere in New York ; Alleghany Pa. ; 

 Lake Superior, Marquette, Detroit, Agricultural College and Port Huron 

 Michigan ; .Stony Creek \'a., and Province of Quebec near Ottawa. 



Life history and habits. The larvae or borers winter under the bark. 

 They begin to transform to pupae in the early part of May. Mr Adams 

 states that larvae had straightened out though none had assumed the pupal 

 form May 5, 1900, and that on the 27th some had changed color. Most of 

 the pupae were a pure white on this later date, though a very few had 

 commenced to color. June 3, no beetles had emerged, and more of the 

 pupae had assumed a dark color. j\Iay 29, 1899, he removed some adult 

 beetles from birch, and found many pupae, and few larvae. June 2, beetles 

 began to issue from dry sticks, and on July 14, he found some young larvae 

 about I4 inch in length at work in the cambium layer, at which time they 

 had traveled some distance. The presence of this insect may be detected 

 by the reddish discoloration of about y^ inch in width, caused by the 

 e.xudation of sap and the ejection of excrement. The dying of the tops 

 of infested trees is another characteristic [pi. 40, fig. i]. The borer 

 first attacks the tops, killing the upper limbs, while the lower branches 

 remain green. Its presence is also indicated by uneven, wavy appearances 

 on the bark, showing more or less regular spiral ridges on the smaller 

 branches. The burrows of this insect are very irregular and interlace in a 

 most perple.xing manner. Plate 40, figure 2, is a photograph taken by 



