192 



SCIENCE 



[X. S. Vol. XXXH. No. 814 



Discussed by D. W. Johnson, F. E. Matthes, 

 W. M. Davis and the author. 



Meanders and Scallops: Maek Jeffebsox, Ypsil- 



anti, Mich. 



Meanders, or balanced swings in river courses, 

 occur from source to mouth, though most fully- 

 developed in the plains part. The embayments or 

 scallops produced in their upper course by mean- 

 ders that come in contact with the bluff are of 

 identical measurement with the meanders and 

 serve to estimate the ancient volume of the stream. 



Beach Cusps: Mabk Jeitebson, Ypsilanti, Mich. 

 Beach cusps are the points of gravel or sand 

 that occur at times on almost all beaches where 

 these materials exist. Perspective foreshortening 

 gives them a fictitious appearance of regularity. 

 They are caused probably in various ways, by 

 waves that play squarely on shore, either under 

 on-shore winds, or in still weather after storms 

 when the diminishing waves accommodate them- 

 selves more and more to the shape of the bottom 

 and the configuration of the shore. 



Beach Cusps: D. W. Johnson, Cambridge, Mass. 

 This paper presented the results of studies of 

 beach cusps found on various types of shorelines. 

 The character and occurrence of the cusps were 

 described. Several theories advanced by previous 

 writers to account for the formation of the cusps 

 were reviewed, but do not seem competent to 

 explain the observed phenomena. An alternative 

 theory was proposed, which receives support from 

 the artificial production of beach cusps. 



A Progress Geological Map of Oklahoma: C. N. 



GiouLD, Norman, Okla. 



The paper indicated by means of charts and 

 otherwise the work that has been and is now 

 being done in the study of the geology of the 

 state. 



Discussed by Arthur Keith. 



Salt Marsh Formatkm near Boston, and its Geo- 

 logical Significance: Chables A. Davis, Wash- 

 ington, D. C. (Introduced by David White.) 

 A description of some of the salt marshes near 

 Boston, including newly discovered facts regard- 

 ing the way in which they are formed and their 

 bearing on geological history. These marshes have 

 not been formed in depressions behind barrier 

 beaches as the result of filling by plants and sedi- 

 ments in the resulting ponds, but ha,ve quite a 

 different origin which is plainly indicated in their 

 structure, and in the character of the plant ma- 

 ■ terial contained in them. The marshes contain 



easily interpreted records of a continued post- 

 glacial coastal subsidence that is still going on 

 at a steady and uniform rate that it is possible 

 to determine. The interpretation of these deposits 

 also has an important bearing on the theories of 

 formation of coal. 



Remarks were made by A. W. Grabau. 

 Observations on Mate of Sea Cliff Erosion: 



Chables P. Bebket, New York, N. 1'. 

 The Permo-carbonic Conglomerates of South 

 Brazil: J. B. Woodwobth, Cambridge, Mass. 

 The bowlder-bearing Permian beds of south 

 Brazil for which Derby proposed a glacial origin 

 in 1888, and sagaciously likened to the deposits 

 of India, were searched in 1908 for evidences of 

 glaciation not previously found. Striated stones 

 including probable fragments of disrupted glaci- 

 ated flows were found in tillite beds on the Rio 

 Jaguaricatu in northern Parana, and similar phe- 

 nomena, especially striated stones, in the states 

 of Sao Paulo and Santa Catharina. Much of the 

 bowlder-bearing group demands floating ice at 

 sea-level, as shown by a depauperated marine 

 fauna between bowlder beds in the valley of the 

 Rio Negro. Certain tillite beds seem best ex- 

 plained as ice-laid deposits derived from an 

 easterly source through ice-action capable of dis- 

 rupting and transporting seaward certain readily 

 recognized rocks of the series inferior to the 

 glacial beds. The paper as presented was illus- 

 trated by stereopticon views showing geology and 

 topography of the area, as a part of the results of 

 the first Shaler Memorial Expedition. 



Discussed by Bailey Willis and I. C. White. 

 Age of the " Caldferous " Formation of the Mo- 

 hawk Valley, N. Y.: E. 0. Ulbich and H. P. 

 CuSHiNG, Washington, D. C, and Cleveland, 0. 

 The Little Falls dolomite of the Mohawk Valley 

 is found to consist of two distinct formations, the 

 lower a dolomite formation of Ozarkian age, the 

 upper a limestone of lower Beekmantown age, 

 with a distinct unconformity between the two. 

 The Beekmantown thins to the west so that west 

 of Little Falls, the Lo-n-ville lies on the Ozarkian. 

 The unconformity can be followed into the Cham- 

 plain Valley, reappears in the St. Lawrence re- 

 gion, and is believed to mark the line of division 

 between the two formations everywhere in north- 

 ern New Y'ork. Locally, about Saratoga, a very 

 fossiliferous limestone lens appears in the basal 

 portion of the dolomite formation. 



Edmund Otis Hovet, 



Secretary 

 {To be continued) 



