Platynin^ . 3 



In the present paper I have Hmited investigation solely to the 

 old composite Platynns of our lists, the genera with fimbriate 

 ungues being omitted. Olisthopus, having simple ungues as in 

 Platynus but differing in having no mentum tooth, has been previ- 

 ously reviewed (Mem. Coleop., IV, p. i68) and is therefore also 

 omitted. The species are extremely numerous and are probably 

 at least a thousand in number in North America, and, so far as 

 known to me at present, may be assigned to fifteen genera as 

 defined below, of which five are entirely neotropical. Only inci- 

 dental reference is made to the grouping of LeConte (1. c, p. 40) 

 or to that of Zimmermann (Tr. Am. Ent. Soc, 1869, p. 244), as I 

 preferred to work out as nearly as possible an original scheme, 

 which by comparison with the others, will furnish additional co- 

 ordinated data to aid future students of this very difficult subject. 

 The elaboration of this review of the species of my collection has 

 involved a great deal of hard work, and its completeness has been 

 aided materially by a number of friends to whom I return sincere 

 thanks in the name of future students of the various genera. Prof. 

 Wickham sent a particularly interesting collection and Mr. Loding, 

 of Mobile, sent some rare or local forms that I had long wanted, 

 such as Platynus quadrimaculatiis and picticornis, both very peculiar 

 and isolated types. Mr. Knaus also sent a number of valuable 

 specimens, and to others, among whom are Prof. Cockerell, Mr. 

 Leng, Mr. Tom Spalding and Mr. Beutenmiiller, my thanks are 

 due for lesser but none the less appreciated favors. 



The genera may be tabulated as follows: 



Pubescence of the antennae beginning on the fourth joint 2 



Pubescence beginning on the third joint; body very small, rather 



convex 1 1 



2 — Body apterous, depressed, elongate, the legs and antennae long and 



slender, the third antennal joint distinctly longer than the fourth.. 3 

 Body winged, except in some subgenera ol Anchomenus; surface less 



depressed, generally convex 4 



3 — Elytra shining, frequently with irregular interstitial punctures, the 



striae deep, the intervals convex; prothorax long, subcordiform, 



The type has been compared carefully with the same sex of pusillus and I have 

 scarcely any doubt of the specific validity of puncticeps; pusillus is present in ample 

 series in my collection from Rhode Island to Montana, and is invariably smaller and 

 much narrower than puncticeps, but the head toward base frequently becomes almost 

 as conspicuously punctate. 



