342 SCOLYTID^. 



[LeConte. 



tignous; middle and hind coxae more or less separated; tibiae compressed, 

 toothed or with transverse ridges on the outer side; armed with a terminal 

 hook at the inner apical angle. Tarsi in some genera filiform and 5-jointed; 

 in others 4-jointed, with the third joint either narrow, or dilated and bi- 

 lobed; last joint long, with large, simple, divergent claws. 



The insects of tliis family are mostly of cylindrical form, and small size- 

 They are the most formidable enemies of trees, sometimes devastating the 

 forests, especially of conifere, by appearing in incredible numbers: the bur- 

 rows are chiefly betvveen the wood and the bark, though some genera pene- 

 trate more deeply (Xyloteres, &fc). The patterns made by them are complex 

 and vary according to genus and species; those of several European species 

 arc figured in the excellent work of Ratzeburg,* and since descriptions of 

 our species are now accessible, so that their identification is easy, I trust 

 that those interested in the preservation of our forest trees may direct their 

 attenti(m to this important subject. Specim-ns of the ravages of these in- 

 sects should be carefully collected, with individuals taken from the bur- 

 rows, and these should be deposited in some museum where they will be 

 carefully preserved for future study. 



Since the publication of my revision of this fauiily.f a few additional 

 species have been found, and a renewed study of the genera has rendered 

 necessarj' some modification of the chissification there proposed. 



The great difi'jrences exhibited by Platypus, and its allies, indicate the 

 propriety of separating them as a distinct sub-family, a course already 

 adopted by Lacordaire. 

 First joint of tarsi as long as the otliers united PLATYPODID^E. 



" " " much shorter tlian the others 

 united SCOLYTID^. 



Sub-family I. PLATYPODID^. 



Head large, not covered by the prothorax, front wide, oblique or vertical ; 

 labrum small, but distinct. Beak wanting; eyes rounded, not convex, 

 finely granulated in our species. Antennae witii large scape (elongated and 

 curved in some foreign genera), and large compressed solid club, which is 

 pubescent except for a small space at the bass; funicle composed of four 

 small joints. Prothorax elongate, truncate before and bisinuate behind; 

 subsinuate on the sides; flanks broadly excavated for reception of front legs. 

 Prosternum moderately long in front in the coxae, which are very large, 

 conical, exserted and contiguous in our species; space behind tlie coxae very 

 short. Pronotum considerably longer than the under surface; middle of 

 base notched for reception of the carina of tlie mcsonotum. Mesosternum 

 triangular, middle coxae narrowly separated; episterna very large, quad- 

 rate, occupying the space formed by the prolongation of the pronotum; epi- 



*Die Forst-Insecten, Vol. i. 



fSynopsis of the ScolyUdce of America, north of Mexico, bj' C. Zimmermann, 

 M.D., with notes and additions by J. L. LeConte, M.D. Trans. Am. Ent, Soc. IKKS, 



m. 



