NO. 10 MORPHOLOGY OF GNATHOTRICHUS — SCHEDL I5 



C. Gnathotrichus sulcatus Lee. 



Cryphalus sulcatus Leconte, 1868. 

 Pityophthorus sulcatus Leconte, 1876. 



Common Names 



A. Gil. matcriai'ius Fitch. 



Pine timber-beetle (Fitch). 



Timber-beetle (Hopkins, 1893). 



Eastern pine wood stainer (Hopkins, 1904, Felt, 1906). 



B. Gn. retusus Lee. 



Timber-beetle (Hopkins, 1893, Swaine, 1914). 

 Pine hole borer (Swaine, 1914). 



C. Gn. sulcatus Lee. 



Western hemlock wood stainer (Hopkins, 1904). 



The Chitinous Skeleton of the Adult 



GENERAL APPEARANCE, VESTITURE, COLOR, AND SIZE 



The general form of all three species is slender in both sexes, 

 cylindrical, with the head concealed from above by the pronotum. The 

 pronotum is longer than wide with the sides parallel on more than 

 the caudal half and broadly rounded in front. The elytra are slightly 

 narrower or as wide as the pronotum, subparallel as far as the origin 

 of the declivity, sometimes slightly tapering posteriorly; moderately 

 broadly rounded behind. 



Length and relative proportions. (Dorsal aspect). — 

 Gnathotrichus materiarius Fitch. 



Length of the body (elytra and pronotum; head concealed 

 from above), 3.06 mm. 



The body is 3.11 times as long as the width of the pronotum. 



Width of pronotum, 0.98 mm. 



The elytra are 1.46 times as long as the pronotum. 



Examined specimens, 12. 

 Gnathotrichus retusus Lee. 



Length, 3.72 mm. 



The body is 3.23 times as long as the width of the pronotum. 



Width of the pronotum, 1.15 mm. 



The elytra are 1.54 times as long as the pronotum. 



Examined specimens, 10. 



