Twelfth Eeport of the State Entomologist 245 



*' From the present appearance of the elms throughout the towns of 

 Central Illinois, where I have had an opportunity to examine their con- 

 dition, and from the rapid progress which this pest has made among them 

 during the last two or three years, it seems extremely likely that it will 

 totally exterminate the trees unless it be promptly arrested by general 

 action." A serious attack is recorded upon the elms at Frankfort, Ky., 

 in 1892, when several were killed and a number badly injured. The 

 insect has also been very destructive to elms in Albany and in Glovers- 

 ville, N. Y. It does not appear to be so injurious in Canada as in the 

 United States. It has been found infesting a dead maple by Mr. 



Harrington. 



Description of the Insect. 



The beetle is an innocent appearing slate-colored insect with dull 

 orange markings as follows : a curved line behind each eye, a line on each 

 side of the thorax, and margined wing-covers with three nearly equidistant 

 points extending from the border. They vary in length from about one- 

 third to one-half an inch. The females are considerably stouter and 

 with shorter antennae than the males (PI. VII, fig. 2). 



The borers (the larvae of the beetles), are similar in form and general 

 appearance to the notorious round-headed borer of the apple, belong- 

 ing, indeed, to the same genus. They rarely exceed three-fourths of an 

 inch in length, are destitute of feet, and have the usual enlargement of 

 the first segment of the body immediately behind the head. (Forbes.) 



The larva is white, subcylindrical, a little flattened, with the lateral 

 fold of the body rather prominent; end of the body flattened, obtuse, 

 and nearly as wide at the end as at the first abdominal ring. The head 

 is one-half as wide as the prothoracic ring, being rather large. The pro- 

 thoracic segment, or that next to the head, is transversely oblong, being 

 about twice as broad as long ; there is a pale dorsal corneous transversely 

 oblong shield, being about two-thirds as long as wide, and nearly as lung 

 as the four succeeding segments; this plate is smooth, except on the pos- 

 terior half, which is rough, with the front edge irregular and not extend- 

 ing far down the sides. Fine hairs arise from the front edge and side of 

 the plate, and similar hairs are scattered over the body and especially 

 around the end. On the upper side of each segment is a transversely 

 oblong ovate roughened area with the front edge slightly convex, and 

 behind slightly arcuate On the under side of each segment are similar 

 rough horny plates, but arcuate in front, with the hinder edge straight. 

 (Packard.) 



The larva differs from the allied linden borer, Saperda vestita Say, in 

 its shorter, broader, and more hairy body, and having the tip of the abdo- 

 men hairy and more depressed. The prothoracic segment is broader and 

 flatter, and the rough portions of the dorsal plates are larger and not so 

 transversely ovate. The mandibles are much longer and more slender, 

 and the antennae much smaller than in S. vestita. 



