118 THE SCOLYTID BEETLES. 



punctures and with striis distinctly impressed and finely punctured ; 

 otherwise as in female. 



Typical male labeled, name label, "Hopk. 1/22/08, H. S. 40, $ , 

 Grand Ledge, Mich., 20.5" ( = May 20). 



Variations. — The length varies from 3.5 to 5 mm., with the average 

 about 4.7 mm. The color varies from reddish to reddish-brown, with 

 the head and thoracic segments ranging from hght to dark brown, 

 and nearly black. The epistomal characters are more constant in 

 this and the next species, otherwise the usual variation in the sculp- 

 ture and vestiture of the head, pronotum, and elytra prevails. The 

 greatest variation, other than size, is found in the punctures of the 

 pronotum and in the strial punctures and interspacial rugosities of 

 the elytra. 



Distinctive characters. — The characters which distinguish this 

 species from the following, to which it is more closely allied, are the 

 much smaller average size of the individual and the coarser and 

 deeper punctures of the pronotum. 



Revisional notes. — The original description was based on two male 

 specimens labeled "Canada," which havebeen examined by the writer 

 and found to agree with the common species which lives in the 

 eastern larch. The comparison in the description with D. ohesus 

 must refer to D. yseudotsugx Hopk., representatives of which were 

 then confused with the true D. ohesus (Mann.) . The smooth intervals 

 on the declivity referred to is a male character. The reference to a 

 much deeper sutural stria relates to what is now recognized as 

 stria 1. The revision relates to the type specimens. With our 

 present knowledge of the specific characters, those given in Le Conte's 

 tables are only partially applicable. It is evident that no other 

 species were confused with this one in Le Conte's description and 

 revision, but it was involved in the revision under D. ohesus (1868) 

 andi>. similis (1873). In 1900 it was in Le Conte's collection under 

 D. ruji-pennis, labeled ''Lake Superior" and "Tex.," and under 

 D. similis, labeled "Lake Superior" and "Can." In Dietz's revi- 

 sion, the specimens from Colorado and California were evidently 

 D. pseudotsugse, but did not involve any confusion in the description, 

 except in the length, 6.2 mm., which was evidently based on a 

 specimen of D. pseudotsugse. 



The species was found to be represented in the Horn collection by 

 one specimen, under simplex, labeled "Can.," and two specimens 

 under D. similis, labeled "Can." 



Pupa. — In addition to the generic, divisional, and subdivisional 

 characters, the apex of the front and middle femora has a minute 

 subapical granule. Abdominal tergite 1 with very small and 2 to 6 

 with stout, prominent pleural spines, 1 without dorsal or lateral, 2 

 without dorsal, 3 to 6 with prominent dorsal spines, becoming larger 

 toward 6, 2 to 6 with two lateral spines each side, becoming more 



