I 



Wickhawh — Fossil Beetles from the Sangamon Peat. 139 



during this stage their formation may be sufficiently remote in 

 time to allow of some specific differentiation. We must take 

 into account also the rather wide separation in space of the 

 two places- — but I very strongly question if ten species of the 

 Carabidse, Dytiscidse, Staphylinidse and Chrysomelidse taken at 

 random in a recent Illinois bog would all be different from 65 

 species of the same families collected during the same year 

 and in similar surroundings at Toronto. I doubt if season has 

 much to do with the divergence in character of the fossils 

 since peat deposits v^ould continue forming all through the 

 warmer parts of the year and insect remains might readily be 

 preserved at any time. The fact that there is no evidence of 

 intrusion of southern types in the Mahomet collection would 

 suggest that the deposit was perhaps formed when the Illi- 

 noisan glacial movement was well advanced on its southward 

 route or at any rate previous to a far northward recession. 



The species and varieties described in this paper are all new 

 to science and are arranged by families as follows : 



Caeabidje Dttiscidje 



Carabus mseander sangamon Agabus savagei 

 Patrobus henshawi praelugens 



Platynus pleistocenicus Staphylinid^ 



subffelidus ^i , • i • i 



Q^\^\^\ Olophrum mterglaciale 



Chlsenius plicatipennis Chrysomelidje 



Donacia styrioides 



All of the types are to be found in the Museum of the Uni- 

 versity of Illinois. 



Carabus m^andee Fisch., var. sangamon new variety (fig. 1). 



Eepresented by part of a wing cover, evidently the inner 

 basal area of the left elytron, about G-OO""" in length by 2-35"'"" 

 in width, more or less damaged on all margins. The sutural 

 bead is like that of recent specimens ; immediately exterior to 

 it is a very fine, scarcely visible carina which corresponds to a 

 similar line (of great variability in distinctness) on the living 

 insect. The first row of tubercles has the basal one elongate, 

 as usual in modern individuals, while in the second row those 

 near the base are short as in most of the specimens in my 

 cabinet. The third row is not well preserved. The carina 

 between the first and second series of tubercles is interrupted 

 instead of being entire and this carina, as well as the tubercles, 

 is more irregular and less smooth than in any of my recent 

 examples. The carina between the next two rows ef eleva- 



