ABSTRACTS OF PAPERS 109 



Extinguisher ("Billings Butte") fauna, is probably capped by the Extinguisher 

 fauna; (b) Mount Rearguard ("Iyatunga"), stated to contain a well exposed 

 section of the Titkana, exposes in its place a fine section of the Lynx; and 

 (c) Mount Mumm, the type locality for the "Munim" formation, contains 

 neither the "Munim" nor its equivalent (the Tatei), but does expose, in the 

 described position for the "Munim," the "Hota" and the lower portion of the 

 Chetang. 



Evidence is presented for a number of other discoveries, the more important 

 of which are: (a) the stratigraphic position of the hitherto unplaced Extin- 

 guisher fauna; (b) the contact between the Upper Cambrian and the Ordo- 

 vician ; (c) the upper half of the Lynx formation; (d) the identity of the 

 Titkana and the "Hitka" ; (e) the identity of the Tatei ("Tatay") and the 

 "Mumm"; (/) the bewildering confusion, in the field and in the published re- 

 ports, of the Mumm, Hota, and Tah limestone formations; (g) the Middle 

 Cambrian age of the "Hota," for which the term Adolphus is proposed ; and 

 (h) the fact that it is the "Tah" limestone, for which the term Mural lime- 

 stone is proposed, and not the Hota or the Mahto, which is the source of the 

 drift blocks carrying the new Lower Cambrian subfauna described by Walcott 

 and the Paedeumias described by the writer. 



General fossil collections have previously been recorded and described from 

 three only of the eleven formations listed in the first paragraph. The new 

 conclusions are based on a very brief reconnaissance, but their accuracy is 

 attested by collections from numerous fossil horizons in all but the two basal 

 quartzites of the nine formations now known to occur in the district, as fol- 

 lows : Unnamed Ordovician (Robson?) ; Lynx (Upper Cambrian); Titkana, 

 Tatei, Chetang, and Adolphus (Middle Cambrian) ; Mahto, Mural limestone, 

 and an unnamed underlying quartzite series (Lower Cambrian). 



Presented by title in the absence of the author. 



TRENTON OF CENTRAL TENNESSEE AND KENTUCKY 

 BY PERCY E. RAYMOND 



(Abstract) 



The strata of Trenton age in Kentucky have been carefully studied by Doc- 

 tors A. M. Miller and A. F. Foerste and afford a standard with which to com- 

 pare the somewhat less known series in the Nashville dome. Physical condi- 

 tions differed in the two regions during the deposition of the rocks, so that a 

 satisfactory correlation of the various subdivisions can only be reached through 

 a careful study of the history of sedimentation in both. This history appears 

 to explain the migrations of a "recurrent fauna," and the correlation reached 

 varies in some respects from that generally accepted. 



Presented extemporaneously. 



Remarks were made by E. S. Bassler and E. 0. TTlrich, with reply by 

 the author. 



