224 



SCIENCE 



[N. S. Vol. XXXII. No. 815 



The Fauna of the Girardeau Limestone and of the 



Edgewood Formation: T. E. Savage, Urbana, 



111. 



The Girardeau limestone is exposed over a small 

 area in the southwestern part of Illinois and 

 adjacent portions of Missouri. It consists of thin- 

 bedded, fine-grained, dark-colored limestone, hav- 

 ing a maximum thickness of thirty-five feet. The 

 Edgewood formation rests unconformably upon 

 the eroded surface of the Girardeau limestone. 

 It outcrops in Illinois along the Mississippi River, 

 north of the town of Thebes, where it has a total 

 thickness of about thirteen feet. It is composed 

 of a limestone conglomerate at the base, which is 

 succeeded by a few feet of alternating shale and 

 limestone layers followed by massive, coarse- 

 grained limestone' at the top. Twenty-seven spe- 

 cies of fossils found in the Girardeau limestone 

 and twenty-two species collected from the Edge- 

 wood formation are recorded. Ten of these are 

 new. In these faunas are genera considered char- 

 acteristic of the Silurian. Since the formations 

 underlie strata in this region which correspond 

 with the Clinton beds of Indiana and Ohio, they 

 are referred to a position at the base of the 

 Silurian, below the horizon of the Clinton. 

 The Phylogeny of Certain Cerithiidce: Elviba 



Wood, Waltham, Mass. 



In order to determine the proper application of 

 the term Cerithium, a genotype must be selected 

 as a starting point. The ontogeny of this type 

 gives a clue to the history of the phyliun. By a 

 comparison of ontogeny in recent and fossil forms 

 the phylogeny of the group is worked out. By 

 employing these standards Cerithium as now in 

 use is shown to be a polyphyletic genus. With 

 either Cerithium nodulosum or G. tuberosum, as 

 genotype a large number of species now classed 

 with Cerithium may still be retained in that 

 genus, and as thus restricted Cerithium becomes 

 a monophyletic genus. 

 Mode of Life of the Eurypterida: John M. 



Clarke and Rudolf Rxiedemann, Albany, N. Y. 



Deduced the life habits of these creatures from 

 their anatomy and mode of occurrence. 

 A new Cystid from the Clinton Formation of 



Ontario: W. A. Pabks, Toronto, Canada. 



In Vol. I. of the " Paleontology of Ohio " 

 Meek describes Lepocrinites moorei. This form 

 differs from all other cystids in having pectini- 

 rhombs on plates 15 and 10 in addition to the 

 ordinary ones. Carpenter, Jaekel and Bather con- 

 sider this feature of generic value. The priority 

 of generic names rests with Carpenter (Lepado- 



cystis) . The new species described as Lepado- 

 cystis clintonensis differs in minor details only 

 from the genotype. As Meek's description was 

 based on a single specimen, we have in the present 

 form the second specimen of the genus ever found, 

 and also the type of a new species. 

 Some New Fossils from tlie Cambrian of South 



Attleboro, Mass.: W. B. Hall. (Introduced by 



R. S. Lull.) 

 Notes on the Upper Carboniferous iti Southeastern 



Neio Mexico and Western Texas: G. B. RlCH- 



AEDSON, Washington, D. C. 



A number of sections were described and corre- 

 lated. It was shown that the Upper Carbonifer- 

 ous in southeastern New Mexico and western 

 Texas consists of a variable sequence of strata 

 which are delimited above and below by major 

 unconformities. The stratigraphic position of the 

 disputed " Guadalupian " beds was also shown. 

 The Correlation of the Guadalupian and Kansas 



Sections: J. W. Beede, Bloomington, Ind. 



The Guadalupian limestones of western Texas 

 and southern New Mexico are overlain by the 

 Pecos Valley Redbeds. These beds present the 

 same lithologio features and are of similar .succes- 

 sion as the Redbeds on the eastern side of the 

 Llano Estacado and carry a fauna closely related 

 to them. The gypsums appear to be the equiva- 

 lents of the Greer gypsiuns as exposed in Okla- 

 homa and Texas. If this correlation is correct, 

 then the base of the Capitan limestone is on the 

 same stratigraphic level, approximately, as the 

 base of the Elmdale formation of Kansas and the 

 base of the Guadalupian series on the level of the 

 base of the Cherokee shales. The five thousand 

 feet of Hueco beds would fall below this level. 



The election of the following officers for the 

 year 1910 was announced: 



President — Charles Schuchert, New Haven, 

 Conn. 



First Tice-Presideni — E. 0. Ulrich, Washing- 

 ton, D. C. 



Seeond Yioe-President—S. W. Williston, Chi- 

 cago, 111. 



Third Vice-President — F. H. KJnowlton, Wash- 

 ington, D. C. 



Secretary — Ray Smith Bassler. 



Treasurer — W. D. Matthew, New York, N. Y. 



Editor — Charles R. Eastman, Cambridge, Mass. 



The next meeting of the Geological Society will 

 be held at the Carnegie Museum, Pittsburgh, 

 beginning Tuesday, December 27, 1910. 



Edmund Otis Hovet, 



Secretary 



