52 



FIFTH REPORT OF THE ENTOMOLOGICAL COMMISSION. 



mouth-parta mncb as in Orthosoma. Dorsal prothoracic plate and the segment be- 

 neath as in Orthosoma, but on each side iu front of and above the prothoracic feet is 

 a large hairy tubercle of which Orthosoma has no traces. The remaining segments of 

 the body above and beneath are almost identical in form iind markings with those of 

 Orthosoma. The callosities on the upper side of the abdominal segments differ 

 slightly iu having the transverse areas not divided by a median impressed line, as 

 they are in Orthosoma (see PI. xxxv, Fig. 1). The thoracic feet as in Orthosoma, but 

 the spiracles are much larger in proportion. 



Head as in Orthosoma, except that the front edge of the epicrauium next to the 

 clypeus is smooth and straight, not dentate, as in Orthosoma (PL xxxv, Fig. la). 

 Clypeus and labrum identical iu form with those of Orthosoma, but the stiff bristles on 

 the front edge of the labrum are considerably longer. Antennae three-jointed and as iu 

 Orthosoma, as is the shape of the labium with its two-jointed palpi; the latter, how- 

 ever, much stouter, though not reaching beyond the eud of the labrum. Maxillae 

 as iu Orthosoma, but the four-jointed palpi are a little stouter. Length of body, 

 87mm (3|g inches); breadth of prothoracic segment, 20""". 



2. THE BROAD-NECKED PRIONUS. 



Prionus laticollis (Drury). 



Fig. 13.— Broad-necked Prionus, it.s larva and pupa. After Eiley. 



Though usually living in the roots and trunks of the poplar and balm- 

 of-Gilead, Mr. F. Clarkson states that at Oak Hill, Columbia County, 

 N. Y., this borer infests the black oak, the beetle emerging at twilight 

 during the first two weeks in July. 



Their presence is quickly realized by the odor of the female, which is very power- 

 ful, and can readily be detected 20 feet distant. I placed a female immediately 

 after emergence in an uncovered jar, and wherever I positioned it, on the piazza or 

 elsewhere, the males were attracted from every direction. I captured twenty males 



