NORTH AMERICAN COLEOPTERA. 277 



Notes and Descriptions of Pselaphidte, witb Remarks 

 on the Scydiuieuidie. 



BY E. BRENDEL, M.D. 



Mons. Acliille RafFray took for a diagnostical base of the genera 

 of the tribe Tyrini the length of the last joint of the maxillary 

 palpi, which necessitated the establishment of quite a number of 

 genera consisting, until now, of a single species. Pytna Casey and 

 Tyrus do not differ by any other property. Hamotus and Cercocenis, 

 aside from the different form of the antennae, are differentiated by 

 the length of that last palpal joint which separates Upoluna from 

 Cercocenis, and takes Hamotus elongatus {Tyrus elongatus Brendel) 

 from Hamotus, making a Cercocerus. I hope future discoveries will 

 bring on a justification one way or the other. 



Tj'Chus ludovicianus n. sp. — Form and color of T. longipalpus Lee. 

 and somewhat larger; pubescence not long, sparse. Length 1.9 mm. Head and 

 protborax like T. longipalpus. Elytra more convex ; antenual joints rounded, 

 visibly longer than wide, fifth perceptibly larger, eighth as long as wide, ninth 

 and tenth transverse ; the % anterior trochanters, near the coxal articulation, 

 are armed with a small conspicuous thorn ; metasteruum tumorous in the middle 

 before the posterior coxae, the tumor is divided posteriorly by a wide prismatic 

 groove, the two parts crowned by a large mastoid sharp thorn ; first ventral with 

 a deep digital impression, the last with a deep circular fovea near the apex, the 

 posterior coxae mutually as distant as the width of the capital front; the third 

 palpi joint as long as the last, the inner edge not angulate as the T. longipalpus 

 from Ohio, Illinois and Missouri, which latter has the metasternal tumor not 

 armed, and the antennal joints not rounded, but oblong-conical. 



Louisiana, Mississippi near the Gulf shore (Hugo Soltau). 



Tyclius microptlialnius n. sp. — Unicolorous brown, coarsely, not 

 densely pubescent, impunctate. Length 1.4 mm. %. — Form like T. puperuliis. 

 Head on the eyeline as wide as long, vertex but slightly convex, transversely, 

 longitudinally straight and the supraautennal tubercles but little elevated ; eyes 

 very far below the vertex, consisting of about eight facettes; antennae longer 

 than the head and protborax; palpi of the form of those of T. cognatus ; the 

 base of the pronotum with five or seven very small punctures ; anterior trochan- 

 ters with a very strong, curved spine. 



Canon City, Col. (Wickham) The female is not known, and is 

 perhaps without any eyes. 



Pselajytrichus belongs to the Bythinus group, and should be placed 

 between Tychus and Machcerites. A change of the name Machterites 

 (from ij-ayatpa a knife) into Mach(Brodes is unnecessary, as the tuber- 

 cles of the second palpal joint are absent in some European species, 

 and present in our M. tychoides. 



TEANS. AM. ENT. SOC. XX. OCTOBER, 1893. 



