Apbil 16, 1909] 



SCIENCE 



637 



Age and Relations of the Sankaty Beds: H. W. 

 Shimee, Boston, Mass. (Introduced by W. O. 

 Crosby.) 

 Then the following paper was read: 



Some Features of the Wisconsin Middle Devonic: 



H. P. CiELAND, Williamstown, Mass. 



This paper gave the results of a study of all the 

 outcrops, as far as known, of the Wisconsin 

 Devonic and their contained faunas. In it were 

 discussed : ( 1 ) the relation of the strata to those 

 above and below, (2) the unconformities, (3) the 

 lithological characters and (4) the character, re- 

 lationships and geographical distribution of the 

 faunas. 



Professors Charles Schuehert, A. W. Grabau 

 and H. M. Ami participated in the discussion of 

 this paper. 



The next paper read was: 



Ice-horne Bowlder Deposits in mid-Carhoniferous 



Marine Shales: Joseph A. Tapf, Washington, 



D. C. 



Great numbers of bowlders and other erratic 

 fragmental rock debris occur in the Caney forma- 

 tion of the Ouachita Mountain region in south- 

 eastern Oklahoma. The erratic material consists 

 of bowlders, cobbles and small rock fragments of 

 three general classes, namely : ( 1 ) limestones, 

 siliceous, argillaceous and magnesian; (2) flints, 

 cherts and (3) quartzites. 



The limestones are of various textures and 

 colors, some of which partake of the nature of the 

 quartzites, while others are argillaceous; others 

 yet appear to be dolomitic or perhaps dolomites. 

 Many of the limestone bowlders are massive and 

 homogeneous, while others are distinctly strati- 

 fied and contain two or more classes of limestone, 

 or strata of limestone and flint. 



Flint and chert bowlders are also of common 

 occurrence, and in places are even more abundant 

 than the limestone bowlders. Certain of these 

 flints are stratified or bedded and are black or 

 bluish in color, while others are massive, chalce- 

 donie in character and contain inclusions of drusy 

 quartz. Among these are many of conglomerate 

 and brecciated nature. 



The third group in the general classification of 

 these erratics includes quartzites of dark and red- 

 dish hues. 



These erratic bowlders vary in size from small 

 pebbles to bowlders of enormous size, a few of 

 which attain lengths of more than fifty feet. 

 Many of the smaller bowlders are more or less 

 rounded, while a few are quite perfectly so. The 

 larger ones are, as a rule, angular. 



At three separate localities in the Ouachita 

 Mountain region certain of the limestone and 

 flint bowlders contain grooves and stria as if 

 produced by the action of shore ice. Certain of 

 these strijE also resemble the markings of slicken- 

 sided surfaces. The evidence as to the origin of 

 these gouged surfaces is not conclusive. 



The erratic bowlders contain a comparatively 

 abundant Ordovieian and Silurian fauna. The 

 bowlders are promiscuously scattered in the 

 Caney formation of black and blue shale with 

 local beds of sandstone in the upper part. 



The Caney formation is several hundred feet 

 thick and contains limy concretions or segrega- 

 tions, associated with the erratic bowlders and 

 elsewhere, that contain an abundant fauna of late 

 Mississippian or early Pennsylvanian age. 



The area of bowlder-bearing beds of the Caney 

 formation, as now known, is within the Ouachita 

 Mountain uplift in Oklahoma that extends within 

 a few miles of the Arkansas line to the west end 

 near Atoka. 



The structure of the region is typically Ap- 

 palachian, the rocks being closely folded and 

 thrust northward. 



Upon comparison, both lithologically and fau- 

 nally, the erratic bowlders are found to contain 

 identical characteristics in the Cambro-Ordovician 

 and Silurian rocks in the Ouachita Mountain re- 

 gion of Oklahoma and in the Cambro-Ordovician 

 section in north-central Texas. There are evi- 

 dences of emergence of the rocks of mid-Carbon- 

 iferous time in the western part of the Arbuckle 

 uplift and in the Texas region to the southwest 

 that afi'eet the Cambro-Ordovician and Silurian 

 rocks. The tentative conclusion is that the bowl- 

 ders were transported from a land to the south 

 by the agencies of ice. 



This paper was discussed by Messrs. David 

 White, W. C. Alden and J. A. Taff. 



The last paper on the sectional program was: 



Relationships of the Pennsylvanian and Permian 

 Faunas of Kansas and their Correlation with 

 Similar Faunas of the Urals: J. W. Beede, 

 Bloomington, Ind. 



Owing to physical changes which occurred dur- 

 ing the close of Pennsylvanian time, there occurred 

 a great reduction of Pennsylvanian species, fol- 

 lowed by the introduction of Permian species. 

 This introduction of new species becomes very 

 noticeable in the Elmdale formation and its base 

 is considered the base of the Kansas Permian. 

 The Permian, as here understood, includes the 



