1H(VJ.] 187 



Description of some new North American Coleoptera. 

 BY GEO. H. HORN, M. D. 



The publication of isolated species has always been deemed objection- 

 able by entomological writers. In palliation, the only excuse is, that the 

 several genera and groups to which the species belong, have been but 

 recently monographed by various authors. The species have been de- 

 rived from many localities, of which the insects have been studied and 

 for the most part been known in distinct publications. 



TEOGOSITA. 



T. marginata, picea, eubnitida, depressa, capite thoraceque grosse punctatis 

 hoc postice parnm angustato, lateribus vix rotundatis, margine modice reflexo, 

 angulis posticis acutis parvis, basi rotundata, elytris oblongis, basi vix emargina- 

 tis, humeris rectis, striis punctatis, interstitiis modice convexis, parce rugulosis, 

 biseriatim siibtiliter punctulatis, abdomine confertim subtiliter punctulatis, an- 

 tennis pedibusque piceis. Long. .20-25. 



T. marginata Beauv. Ins. Page 125. PI. 32, fig. 3. 



With some doubt I refer this species to the one indicated by Beauvois. 

 The figures of this author are for the most part recognisable, his descrip- 

 tions not in the least so. This species resembles the pleuralis Horn, 

 from which it difi"ers by its less depressed form, and less rounded sides of 

 the thorax. The head and thorax are more closely punctured. The color 

 is dark brown, with a pale margin to the thorax and elytra. The antennae 

 and legs are pale rufous. Its position in the arrangement of the species 

 of Trogosita, adopted by me in the February number of the Proceedings 

 of the Acad. Nat. Sc, is in advance of the pleuralis. 



For the privilege of studying this species I am indebted to Mr. Henry 

 Ulke, of Washington. It appears to be not uncommon in Ohio and Lou- 

 isiana, whence these specimens were obtained. 



MARGARINOTTIS.* 



M. guttifer, ovalis. convexus, niger, obscurus, ore antennisque rufis, punctatissi- 

 mus rugosus, tuberculis ovalis Isevibus nitidis; pronoto duplici serie transversa, 

 4, 6, elytris lineis longitudinalibus irregularibus, propygidio 5, pygidio 2, tibiis an- 

 ticis 4 dentatis, j^osticis biseriatim spinulosis. Long. .26, lat. .18. 



The difi"erences between this and the only other known species, 

 s caber Fabr., are so striking as scarcely to need comment. In shape it 



* This genus is scarcely distinct from Hister. The sculpturing of the elytra is 

 the character on which Marseul appears to place most reliance, in his enumera- 

 tion of generic differences. 



