60 CLASSIFICATION OF THE SUBFAMILY CRYPHALINA. 
Genus XYLEBORUS Eichh. 
Antennal funicle 5-jointed, joint 5 short and broad; club short, 
broad, anterior face obliquely truncate, with one or two recurved 
sutures, posterior face without sutures; pronotum longer than 
broad, with sides parallel or slightly narrowed toward base, apical 
margin broadly rounded, without serrations; eyes elliptical, emar- 
ginate. 
Norre.—This revised description is based on specimens of Xyleborus monographus 
(Fab.) (Pl. IV, fig. 45), which is the type of the genus Xyleborus Eichhoff. The 
principal characters distinguishing this more restricted genus from those of Euwallacea, 
Ambrosiodmus, and Anisandrus are the more elongate body, the thorax broader than 
long, anterlor margin smooth, and the absence of sutures on the posterior face of the 
antennal club. The genus Xyleborus, as heretofore considered, is far too large, and 
the range of characters is so wide that it is practically impossible to treat it in a. 
synoptic table or key which would indicate natural affinities, but with this separation 
the treatment is simple. It is true that the genera, as here distinguished, might be 
considered subgenera, but the author fails to recognize the advantage or real need of 
the designation of the subgenus or subspecies, believing, as he does, that if a form 
has sufficient distinctive characters to make it worthy of a name it should represent. 
a species or a genus, and that subspecies, especially in insects, will contribute to 
confusion rather than advancement, while genera can be readily separated into 
primary divisions and subdivisions which will serve the purpose obtained by a sepa- 
ration into subgenera. | 
Only species found in America north of Mexico are included in the following 
table and descriptions: 
Apex of elytra obtuse, with a prominent acute granule each side......... Division I. 
Apex of elytra broadly to subacuminately rounded, without prominent granule 
or tooth each) side of the apex 2-25 cc aes se se cee eee ae Division IT. 
DIVISION I. 
Declivity opaque to subopaque.e.. 4.2 222 a eereeereee eee Subdivision A. 
DechyitySbining-. 0-50) eee ciao ee eee ene eer Subdivision B. 
SUBDIVISION A. 
a1. Declivity with interspace 1 unarmed, interspace3 armed with acute granules 
toward apex. 
Baxtervalle; Miss.1m Quercus sp cae See eer eee re quercus, page 63. 
a2. Declivity with interspaces 1 and 3 armed with row of granules. 
61. Elytral interspaces faintly rugose and subopaque, declivity with inter- 
space 2 not strongly impressed and interspace 1 not strongly 
elevated, punctures of strie 1 and 2 obscure..-...... saxesent Ratz. 
62. Elytral interspaces smooth and shining. 
Declivity with interspace 2 scarcely impressed, and interspace 1 scarcely 
elevated, strize 1 and 2 with punctures obscure. 
Waynesboro, Mass. 1m icoria pecan =: 322222 2 eee eee pecanis, page 63. 
Declivity with interspace 2 strongly impressed and interspace 1 strongly 
elevated, strie 1 and 2 with punctures distinct. 
mterprise- ila sccc eo ONS are eee meer floridensis, page 63. 
