VORTH AMERICAN COLEOPTERA. 125 



disc behind ^the anterior margin with a slight depression in front of which is a 

 slight pyramidal elevation of the margin, flat and smooth in front. Elytra wider 

 than the thorax, about one-fourth longer than wide, scarcely broader behind, sur- 

 face vaguely seven-striate, with large variolate punctures rather closely placed, 

 the fouth and sixth intervals wider with irregular variolate punctures with others 

 at the base of the second interval, sides of elytra beyond the seventh row of punc- 

 tures, coarsely and irregularly punctured. Pygidium sparsely and rather finely 

 punctate. Abdomen smooth at middle, coarsely punctured at the sides. Anterior 

 tibise with the outer edge regularly arcuate the anterior face coarsely punctured 

 (except along the outer margin) and with a carina extending nearly the entire 

 length ; tip of tibia obtuse. _Length .8 inch ; 21 mm. (PI. 4, fig. 5.) 



The genus Orizabus was founded by Fairmaire (Rev. et Mag. Zool. 

 1878) for certain Mexican forms closely related to the Australian Chi- 

 roplat^^s, and from which no characters of moment have been given to 

 separate them. In our own fauna Ligyrus and Aphonus are its closest 

 allies, and the species resemble those genera greatly in form and sculp- 

 ture. The anterior tibiae in the species described by Fairmaire are with- 

 out teeth on the outer side, but in one of them, isodonoides, the follow- 

 ing expression is used : tihiifi (iiit.icis . . . extus leviter bismuatis. This 

 latter expression indicates a tendency of the tibia to become dentate, 

 which the following species fully illustrates. 



The two specimens before me were collected by Prof. Snow in New 

 Mexico-. Of the four species described by Fairmaire they seem most 

 closely related to marginatus. 



O. lig.yroides n. sp.^Dark castaneous, shining, beneath clothed with short 

 reddish brown hair. Head densely punctured and opaque, frontal suture sinuate, 

 clypeus in front narrow, the margin reflexed and acutely notched, obtusely biden- 

 tate, a slight elevation at the middle of the clypeal suture. Thorax about one- 

 third wider than long, narrower in front, hind angles broadly rounded, sides fim- 

 briate, base with a distinct marginal line; apical margin thickened and slightly 

 elevated at middle, surface coarsely and rather densely punctured along the apical 

 third, gradually more sparsely posteriorly, a smooth median space posteriorly and 

 one each side nearer the lateral margin. Elytra wider than the thorax, scarcely 

 a fourth longer than wide, slightly broader posteriorly, the surface with seven 

 vague striae indicated by rows of coarse variolate punctures, the intervals 2-4-6 

 broader and with irregularly placed punctures, sides of elytra beyond the seventh 

 row of punctures coarsely and deeply punctured, the punctures arranged in vague 

 rows. Pygidium very finely aad sparsely punctured. Abdomen finely and 

 sparsely punctate. Anterior tibise coarsely punctured, except along the outer mar- 

 gin and apex, a distinct carina extending from base two-thirds to tip, outer edge 

 vaguely tridendate. Length .S<S iuch; 22 mm. (PI. 4, fig. 6. J 



In comparing this species with Snowii we find the form more robust, 

 the sculpture throughout deeper and more pronounced. The thorax is 

 not depressed in front and the apex of the clypeus narrower. 



