ClCINDELID^: 19 



Collaris Csy., is distinct from horni in its generally narrower and 

 more elongate outline and usually stouter and sometimes much 

 more elongate antennae. In the elongate form of the body it re- 

 sembles temperatus and allied forms, but the elytral punctures are 

 always much coarser and closer. The following three may be 

 regarded as subspecies of collaris: 



Omus collaris ssp. antennalis nov. Male stout, but more parallel and 

 less ventricose than in horni, rather shining; head slightly narrower than 

 the prothorax, coarsely but very obsoletely rugulose, nearly smooth and 

 not at all punctate anteriorly; labral lobe very broadly rounded, not 

 prominent; antennae notably long and rather thick; prothorax obtrape- 

 zoidal, a fourth wider than long, the oblique part of the sides nearly 

 straight; thin side margins rather elevated, especially near the base, 

 which they attain by rapidly curving inward; surface medially perfectly 

 smooth, rugulose apically and basally and with transverse rugae laterad; 

 elytra more than two-fifths wider than the prothorax, with parallel and 

 feebly arcuate sides, rapidly converging in apical two-fifths; punctures 

 internally large but shallow, the granule of each small but very con- 

 spicuous; anterior tarsi broadly dilated and very eccentric, the third 

 joint as large as the second; apex of the copulatory spicule long, straight 

 and but feebly deflexed. Length 16.0 mm.; width 6.2 mm. California 

 (Mariposa Co.). 



This is a distinct modification of the collaris section in its unusu- 

 ally long and at the same time thick antennae, somewhat as in 

 ambiguus, almost evenly rounded labral lobe, more truncate 

 apically in the female, and very strongly, subequally dilated an- 

 terior tarsal joints of the male. The male type was taken on July 2, 

 1905, by J. C. Huguenin and the female on June 12, 1914, by Nunen- 

 macher. The female is similar to the male in every detail of 

 sculpture and habitus, but is stouter and with more transverse pro- 

 thorax; the antennae are similarly stout but shorter. 



Omus collaris ssp. trapezicollis nov. Male less heavily built than 

 the male of antennalis and with more slender antennae than in either that 

 or collaris, the elytral punctures smaller and rather deeper than in either, 

 the small acute granules therefore less differentiated though evident; 

 lustre rather opaque, the elytra shining; head distinctly narrower than 

 the prothorax, moderately rugulose throughout, obscuring the feeble 

 anterior punctures; antennae slender, only moderate in length; labral 

 lobe large, prominent, feebly truncate medially; prothorax obtrapezoidal, 

 a fifth or sixth wider than long, the oblique sides subsinuate medially, 

 the acute side margins not quite attaining the base; surface centrally 

 smooth but with fine and very obsolete anastomosing lines, rugulose 

 peripherally; base bisinuate; elytra oblong-oval, two-fifths wider than 

 the prothorax, gradually arcuately narrowing behind the middle; punc- 



