December 12, 1913] 



SCIENCE 



859 



former is Wisconsin while the latter is appar- 

 ently Kausan. Professor Todd evidently cor- 

 relates the deposit with the later Wisconsin 

 when he says : 



This was conclusive evidence that the region had 

 been occupied more or less by timber since the ice 

 had covered the regions, possibly while the second 

 moraine was in process of formation. 



The late work of the Iowa geologists, Cal- 

 vin, Shimek and others, indicates that the 

 underlying blue clay was laid down by the 

 Kansan ice sheet, and hence the fossil remains 

 must be regarded as post-Kansan and pre- 

 Wisconsin. 



From this new angle of view the fossils be- 

 come of great interest. The mollusks were 

 submitted by Professor Todd to Professor E. 

 Ellsworth Call, who recognized the following 

 species.^ 



LimnopJiysa palustris Say. 



Limnophysa decidiosa Say. 



Gyraulus parvus Say. 



Valvata sincera Say. 



Segmentina armigera Say. 



But five species are here recorded, although 

 Professor Todd refers to " nearly a dozen 

 species." 



In the material submitted by Mr. Over, 

 which is a part of the original lot, fifteen spe- 

 cies are recognized, as noted below: 



Fisidium compressum Prime. 



Pisidium variabile Prime. 



Fisidium medianum Sterki. 



Valvata tricarinata Say. 



Valvata lewisii Currier. 



Succinea avara Say. 



Fhysa sp. (immature). 



Galba palustris Miill. 



Lymncsa stagnalis appressa Say. 



Flanorhis trivolvis Say. 



Flanorhis iicarinatus Say. 



Planorbis iicarinatus striatus Baker. 



Flanorhis deflectus Say. 



Planorbis parvus Say. 



Flanorhis exacuous Say. 



Two species, Segmentina armigera and 

 Limnophysa (Oalba) decidiosa, mentioned by 

 Call, were not detected in the material re- 



2 Op. cit., p. 121, footnote. The old momencla- 

 ture is used. 



cently examined. Thirteen species are like- 

 wise included which were not mentioned by 

 Call, possibly because the material did not con- 

 tain them. Valvata sincera as identified by 

 Call also proves to be Valvata lewisii. 



The fauna is thus seen to have been large 

 and varied. The deposit was evidently the bed 

 of a large lake or river, and could not have 

 been a tamarack swamp as stated by Professor 

 Todd, because mollusks such as Valvata tri- 

 carinata and V. lewisii do not inhabit such a 

 station. The tamarack log and cones men- 

 tioned probably floated from the shore and be- 

 came buried in the mud. That this fauna 

 lived in or near the present Ajides Creek is 

 not at all possible, because such an assemblage 

 of life would scarcely be found in this kind of 

 a habitat. 



With just which interglacial stage this biota 

 is to be correlated is not yet clear. If it imme- 

 diately preceded the Wisconsin, which seems 

 probable, it may be Peorian (post-Iowan) ; or 

 if it became extinct before this stage it may be 

 the equivalent of the Sangamon (post-Hli- 

 noian) ; if it is to be classed as post-Kansan, as 

 it lies upon the Kansan till, it must be cor- 

 related with the Yarmouth stage. In the ab- 

 sence of equivalent loess deposits it is difficult, 

 if not impossible, to place this deposit in its 

 true position in the paleontologic column. A 

 restudy of the Grandview deposits from the 

 modern, multiple glacial standpoint would 

 assist greatly, doubtless, in solving this 

 problem. 



My thanks are due to Dr. Bryant Walker 

 and Dr. Victor Sterki for kind assistance in 

 the determination of doubtful material. 



Frank C. Baker 



The Chicago Academy op Sciences 



THE INDIANA ACADEMY OF SCIENCES 



The Indiana Academy of Sciences and the Indi- 

 ana Conservation Association met in joint session 

 in Indianapolis, October 24-25. Some of the im- 

 portant papers were as follows : 



President Donaldson Bodine 's address on ' ' How 

 to Increase the Efficiency of the Academy." 



"The Flood of March, 1913." 

 At Terre Haute, Charles B. Dryer. 

 At Fort Wayne, L. C. Ward. 



