850 E. O. ULRICH CORRELATIONS OF CHESTER FORMATIONS 



ously developed in Monroe County. Locally, as to the north or northeast 

 of Prairie clu Rocher, it is wanting where it would be if present. Now, 

 I have no information regarding this sandstone at the supposed Renault 

 crinoid locality which lies about 3 or 4 miles to the southeast of Burks- 

 ville; but this place is not far off the line on which the Aux Vases is 

 locally wanting, so that the true Renault rests directly on older forma- 

 tions. Perhaps this is the case at the crinoid locality. If so, then this 

 crinoid bed may not be Renault in age, but pre-Aux Vases, which would 

 help paleontological correlation very greatly. 



This suggestion may prove in error, but in the meantime there is much 

 in favor of it besides the direct testimony of the crinoids themselves. 

 (1) So far as I know, none of these crinoids occur in exposures of the 

 typical Renault that are underlaid by Aux Vases sandstone. (2) The 

 material in the Springer Collection from the locality southeast of Burks- 

 ville contains only one species of Talarocrinus, and this I have not suc- 

 ceeded in distinguishing from the Shetlerville variety of T. trijugis, 

 whereas it does seem to differ from all of the three or four species of the 

 genus that I have collected from unquestioned outcrops of the Renault. 

 (3) Platycrinus huntsvillce , which is rare in the Upper Ohara of Ken- 

 tucky and Indiana and probably failed entirely before reaching Illinois, 

 does not occur in the questioned Monroe County Renault collections 

 available to me, but Dizygocrinus persculptus, which I based on speci- 

 mens from the Sainte Genevieve limestone in western Kentucky, does 

 occur in the Monroe County collections as well as in those from the 

 Upper Sainte Genevieve of Indiana, Kentucky, and Alabama, in all of 

 which it is associated with the Platycrinus. (4) The genus Pentremites 

 is but sparingly represented in the questioned Renault of Monroe County, 

 and the few specimens present are not of kinds found in the true Renault 

 of Missouri or like those commonly met with in the Lower Gasper of Ken- 

 tucky, but rather of Ohara forms. Finally (5) none of the other classes 

 of fossils that are associated with the crinoids at the questioned Renault 

 locality include anything that might not be expected in an Upper Ohara 

 zone as well as in one of post- Aux Vases age. 



In my 1917 report (page 181) I listed 9 species from the vicinity of 

 Huntsville, Alabama, as Gasper oolite fossils, with the statement by 

 Doctor Springer that he has "all of these species also from the Renault 

 formation in Monroe County, Illinois." At that time I had no reason to 

 doubt the age of the crinoid bed near Burksville to which Doctor 

 Springer's statement refers. Besides, the position of the crinoid beds in 

 the Huntsville section was not exactly known. Indeed, it was believed 

 that crinoids like those in the supposed Renault of Monroe County oc- 



