NORTH AMERICAN BOSTRICHIDAE 131 



brum transverse, subtruncate and densely ciliate with long, yellow- 

 ish hairs in front; maifdibles broad, more or less attenuate toward 

 apices; eyes large, oval, globose, strongly projecting. Antenna mod- 

 erately long, 10-segmented ; first and second segments robust, first 

 elongate, arcuate, slightly flattened on underside, second quadrate or 

 oval, much shorter than first ; third to seventh segments short, trans- 

 verse, compact, united shorter than first segment; last three seg- 

 ments forming a large, loose, compressed club, the segments densely 

 clothed with short, erect hairs, each with two round sensory depres- 

 sions on each surface, eighth and ninth segments oval, subequal in 

 length to each other, tenth elongate, longer and narrower than ninth. 

 Pronotum strongly convex, truncate in front, broadly, arcuately emar- 

 ginate at base, dentate anteriorly, not transversely depressed behind 

 anterior margin; sides not margined. Scutellum small, quadrate. 

 Elytra strongly convex, sutural margins scarcely elevated on apical 

 declivity; each elytron with two tubercles along anterior margin of 

 apical declivity. Legs short, subequal in length; tibiae flattened, 

 slightly expanded toward apices, dentate on exterior margins, each 

 with a moderately long, slightly arcuate spine at apex ; tarsi slender, 

 posterior pair as long as, or longer than tibiae, apical segment of each 

 shorter than preceding four segments united. Anterior coxae contigu- 

 ous. Middle coxae narrowly separated. Intercoxal process of abdo- 

 men lamellate. Last visible abdominal sternite long. Body short, 

 cylindrical. 



Genotype. — Sinoxylon quadrispinosum LeConte. (Monobasic.) 

 The females of this genus have a bimch of very long hairs extend- 

 ing backward from each side of the last visible abdominal sternite. 

 These hairs are attached on the inside of the sternite at the lateral 

 margins. 



KEY TO THE SPECIES OF XYLOBLAPTUS 



Tubercles along anterior margin of apical declivity of elytra spiniform at apices 



prosopidis, new species, p. 131. 



Tubercles along anterior margin of apical declivity of elytra mamilliform, rarely 



acute, but not spinose at apices quadrispinosus (Le Conte), p. 132. 



Xyloblaptus prosopidis, new species 



Male. — Brownish black to dark reddish brown, with basal half of 

 pronotum and elytra reddish or brownish yellow; underside of body 

 reddish brown, the antennae, palpi, and legs (except sometimes ante- 

 rior tibiae) , brownish yellow. 



Head slightly convex, with two small, obsolete, median tubercles on 

 front, and a small smooth space behind the tubercles, sparsely, finely 

 punctate on front and clypeus, with fine, longitudinal, parallel costae 

 on occiput, sparsely clothed with rather long, erect and recumbent, 

 white hairs ; clypeus vaguely depressed at middle along posterior mar- 

 gin ; clypeal suture distinct. 



Pronotum distinctly wider than long, widest along middle; sides 

 nearly parallel at middle, broadly rounded posteriorly and anteriorly, 

 with a small, broad tooth at apical angles; surface sparsely clothed 

 with short, recumbent and erect, inconspicuous hairs, which are more 

 numerous on apical part, indistinctly punctate on basal half, with a 

 few inconspicuous, cuneiform punctures on median part, rather 

 densely, irregularly dentate on apical half, the teeth broad, semierect, 

 variable in size, and rasplike, with two or three larger teeth on each 

 side near apical angles. 



