FOSSIL COLEOPTERA rj 



Tachys Schaum. 



T. HAYWARDi n. sp. (Plate I, Fig. 1.) Form scarcely elongate for this 

 genus. Head of moderate size, eyes normal, antennae wanting, front finely 

 punctured. Prothorax broader than the head, about one and two-fifths 

 times as broad as long, widest slightly in front of the middle, median line 

 indicated but not deep, base a little narrower than the apex, sides nearly 

 regularly arcuate, not sinuate, angles not prominent, thoracic disk punctu- 

 late, basal and marginal beads fine. Scutellum small. Elytra much wider 

 than the prothorax, sides rather strongly rounded, apices pointed, surface 

 scarcely perceptibly striate except that one elytron shows a trace of a stria 

 near the outer tip which may represent the strong groove found in that 

 position in many of the recent species. Legs wanting. Length, 2.85 mm. 



This seems to answer very well to the characteristic appear- 

 ance and small size of the genus Tachys, and is the first species 

 described from the Florissant Tertiaries. I do not feel that it is 

 safe to try to indicate its relationships with the numerous modern 

 forms. The name is given in memory of my friend, Roland 

 Hayward, whose paper on Tachys is a most helpful contribution. 



Platynus Bon. 



P. FLORISSAXTEXSIS n. sp. (Plate I, Fig. 2.) Form similar to that of 

 the recent P. melanarius. Head of moderate size, antennae slender, extend- 

 ing back to the basal third of the elytra, eyes not well defined. Prothorax 

 strongly and regularly rounded on the sides, the width equal to a little less 

 than twice the length of the median line, base not well defined so that the 

 hind angles cannot be made out, but they are apparently rounded into the 

 sides and base, or at least extremely indistinct. Elytra about equal in 

 length to one and one-half times their conjoint width, very finely striate 

 and with no visible interstitial sculpture though the striae themselves show 

 indications of being finely punctate. Legs wanting, excepting a portion 

 of one of the hind pair which shows nothing of importance. Length, from 

 front of head to elytral apex, 8.85 mm. 



Compared with recent species, this would remind one of P. 

 placidus by the fine striae and of P. melanarius by the size and 

 form. It does not resemble the fossil P. tartareus of these shales. 



Hydrobius Leach. 



H. TITAN n. sp. (Plate II, Figs. 4, 5.) Form more narrowed anteriorly 

 and posteriorly than in the recent H. fuscipes. Head of moderate size, 

 finely and closely punctate over the entire upper surface. Palpi with the 

 terminal joint larger than the one preceding. Prothorax narrowed an- 

 teriorly, the sides rather regularly arcuate to the base which is the widest 



