STRATIGILVPHIC TAXONOMY 589 



stone, which formation or group I place at the hase of tlie Chesterian, 

 while Keyes and Weller, in the publications already cited, refer it to the 

 top of the Meramecian. Essentially the same considerations are involved 

 as in the case of the Warsaw. Had Keyes and Weller observed the stratig- 

 raphic break between the Sainte Genevieve and the underlying Saint Louis 

 limestone, they would probably have given less weight to the fact that 

 both are limestones and more to the well marked f aunal differences. Dis- 

 regarding the Spergen element in the Sainte Genevieve fauna — which may 

 well be done considering that it reappears in equal strength at least twice 

 afterward — the remaining constituent, as I have shown elsewhere,'^* is 

 decidedly Chesterian. ' Warping and consequent shifting of seas undoubt- 

 edly took place following the Saint Louis, so that the distribution of the 

 Sainte Genevieve in the Mississippi and southern Appalachian valleys dif- 

 fers widely from that of the Saint Louis. In the Cumberland Plateau 

 and the southern Appalachian region the Saint Louis is commonly absent 

 and in some places, as near Huntsville, Alabama, the little that was de- 

 posited of it appears to have been locally eroded away. The Sainte Gene- 

 vieve in this general region, therefore, rests rather generally directly on 

 the Spergen. 



As to the Cypress sandstone, which Keyes and Weller place at the base 

 of the Chester, this seems to be a local lithological development confined 

 to areas adjacent to the eastern shore of Ozarkia. It doubtless indicates 

 local movement, but, despite close search, no evidence of such movement 

 was detected to the southeast in the Monte Sana section, near Huntsvillo. 

 Here no satisfactory evidence of a stratigraphic break was observed be- 

 tween the top of an 0-6-foot wedge of Saint Louis limestone and the top 

 of unquestionable Tribune limestone. Almost the whole of this interval, 

 comprising perhaps 150 feet of beds, consists of oolitic and crinoidal 

 limestones, the upper third or so containing characteristic Tribune spe- 

 cies, the lower third good Sainte Genevieve fossils. Between these two 

 zones are some 45 feet of beds in which neither of these faunas was recog- 



'* Professional Paper, U. S. Geol. Survey, No. 36, 1905, p. 45 : Analysis of the Ste. 

 Genevieve fauna herein listed brings out the following facts : Out of a total of 75 species 

 8 are confined to and. so far as known, strictly diagnostic of the Ste. Genevieve ; .'i? 

 species are found in the Spergen beneath and in the Tribune limestone above, while all 

 told 58 species are common to the Ste. Genevieve and the Tribune. Further. 17 species 

 of the 75 range from the Spergen through the St. Louis and Ste. Genevieve and, with 

 one or two exceptions, on into middle and upper Chester beds. These long-ranged species 

 therefore, much like the Spergen forms, are to be counted as Tennessean fossils and as 

 having no bearing on the problem beyond the determination of the period. Finally. 26 

 middle Chester species appear for the first time in the Ste. Genevieve, while only 6. in 

 part doubtfully identified species, come up from the St. Louis and are unknown above the 

 Ste. Genevieve. At the best, then, the faunal alliances of the Ste. Genevieve may be ex- 

 pressed by the ratio of 26 for the Chesterian to 6 for the Meramedau. 



