23 



The pronotum is wider than long, 33:29, rather strongly arcuate on the 

 sides, and narrowly rounded on the middle line in front; sculptured and 

 pubescent almost exactly as in obesus, subconcentrically asperate in front, with 

 four median asperities on the apical margin; very finely rather closely punctured 

 behind. 



The elytra have nearly the same shape as obesus, but are slightly more 

 slender. The punctuation is nearly as in obesus, but the strial punctures are 

 relatively somewhat larger and rather widely separated; the interstrial punc- 

 tures at the base nearly as large as those of the striae and confused, elsewhere 

 on the disc very small, variably confused to nearly uniseriate, very densely 

 confused along the side margins. The declivity has the striae impressed; the 

 strial punctures larger than on the disc; the interspaces narrower than in obesus 

 and rather regularly uniseriately granulate, with few interspersed punctures; 

 the ridge of the seventh interspace well-developed and acute, but less so than in 

 obesus, more distinctly arcuate in outline, and bearing four or five small, widely 

 separated granules; with the caudo-lateral impressions as in obesus, The 

 pubescence is rather abundant, light coloured, long, slender, and erect. 



Description of the male. Length, 1 6 mm. ; smaller, more slender, and 

 distinctly more fragile than the male of obesus. 



The head has the front convex, coarsely, not closely punctured; the 

 epistoma depressed, densely punctured, with the usual fringe of hairs. 



The pronotum is subcircular, slightly wider than long, finely, not densely 

 punctured, with scattered small acute granules on the cephalic half, almost 

 exactly as in obesus, and similarly clothed with long slender pubescence. 



The elytra are wider than the pronotum, arcuate on the sides, widest 

 slightly before the middle, arcuately narrowed from there to the apex, elongate, 

 with the apex very narrowly rounded, very strongly convex, shaped practically 

 as in obesus; the striae hardly impressed, the strial punctures moderately coarse, 

 deep, more widely separated than in obesus; the interstrial punctures nearly as 

 large as those of the striae, the interspaces about the sides very densely punctured 

 and sub-granulate, those of the declivity faintly granulate; the pubescence as in 

 obesus, long, slender, curved, erect and longer about the margin. The ridge 

 of the seventh declivital interspace is obtusely carinate, not subacute as in the 

 male of obesus. 



Distinctive characters: The female is distinguished from obesus by the 

 constantly smaller size, slightly but distinctly more slender form, and chiefly 

 by the declivital ridge of the seventh interspace being less acute and without 

 the elongate serrations of obesus. The male is extremely rare and is represented 

 in our collection by four bred specimens. It appears to be rather more slender 

 than the male of obesus, and is very much smaller, with the front coarsely 

 punctured and the punctures of the elytral interstriae nearly as large as those of 

 the striae. 



Variations : The size is constant in our large collection of females. The chief 

 variations are in the details of the elytral punctuation and these are within 

 moderate limits. 



Ste. Anne de Bellevue, Que., in trunks of Populus. Abundant in weakened 

 and dying trees in the region about Montreal Island and in the Ottawa Valley. 



Xyleborus xylographus, Say. 



So far as we can learn the type is not in existence and has apparently not 

 been seen since the time of Dr. Harris. There is a single metatype in the Harris 

 collection at Boston, labelled, "744, N.C.," "Tomicus xylographus Say, 744, 

 teste Say." This specimen should apparently be accepted as fixing the species. 



Length 2-7 mm., rather slender, the pronotum rather strongly and closely 

 punctured behind, the punctures of varying size, the elytral striae slightly 



