8 MEMOIRS ON THE COLEOPTERA 



larly punctate, the punctures becoming gradually feebler and sparser 

 internally, but with the large sparse fovese less diffuse and more sharply 

 marked; anterior tarsi (9 ) short, stout, with many spiniform hairs, the 

 second joint barely two-fifths longer than wide. Male unknown. 

 Length (excluding mandibles) 19.0-20.5 mm.; width 7.6-8.0 mm. 

 Washington State (Seattle). 



Differs from dejeani as above stated ; the surface lustre in dejeani 

 is almost invariably piceo-subcupreous, but there is no trace of this 

 in the subsidiary form, where the elytra also are broader and more 

 shouldered. 



Omus dejeani ssp. foveatus nov. Form narrower than in dejeani and 

 rather smaller in size, the head and prothorax especially being notably 

 smaller; surface lustre and general sculpture similar, except that the 

 elytral fovese are somewhat larger and deeper and the general punctures 

 deep, more sharply defined and much less close-set; the elongate-oval 

 form of the elytra, with obsolete humeri, is almost similar; anterior tarsi 

 ( 9 ) much more slender than in the preceding but not evidently more so 

 than in dejeani. Male not much more slender than the female. Length 

 18.0-18.7 mm.; width 6.8-7.3 mm. Oregon (Bull Run, Clackamas Co.). 



In dejeani the male is decidedly smaller and less stout than the 

 female and the head and prothorax relatively much larger than in 

 foveatus, being similar in this respect to robustus. Dejeani is moder- 

 ately abundant from northern California apparently to Alaska; 

 at least one example before me is labeled with the latter locality. 



Subgenus Omus in sp. 

 Group I (audouini) 



Since my last revision of this group a rather striking character 

 distinguishing Omus parvulus as a species has come to light. The 

 basal joint of the antennae in both sexes is smaller and shorter than 

 in any of the allied species and, on its posterior face, there is a 

 large and nebulously denned bright testaceous area; this latter 

 feature sometimes occurs in audouini however, in less definite 

 degree and is also described in vandykei. There are numerous new 

 forms in this group as follows: 



Omus audouini ssp. brevicornis nov. Form rather slender, strongly 

 convex, rather shining; head and prothorax as in audouini, except that 

 the rugulosity of the former is rather less pronounced and the labral 

 lobe more broadly and subevenly rounded; antennae notably shorter and 

 even more slender; elytra almost exactly as in audouini throughout, 

 except that they are less elongate; anterior tarsi somewhat more broadly 



