ABSTRACTS 651 



carried on in Mahaska and Keokuk counties and reported upon in 

 Volume IV. The Coal Measure areas are more limited, the areal 

 development of the Augusta is greater, and the Kinderhook comes in. 

 The latter is described as being made up of the Wassonville lime- 

 stone, English River gritstone and Maple Mill shale, of which the 

 latter may possibly be at once the upper continuation of the Devonian 

 and the downward extension of the Carboniferous. The close rela- 

 tionship between the two systems is emphasized. The Pleistocene beds 

 include the Kansan drift, loess-silt and the alluvium. The lowan does 

 not extend into the county and the loess-silt is an extension of the 

 fossiliferous loess of the lowan drift border. 



Appanoose county is of interest in that the Coal Measures show 

 an unusually regular phase of development. The Appanoose beds, as 

 they have been called, include limestone, shales and a coal seam, which 

 maintain their thickness and general character throughout an area of 

 about 1500 square miles in Iowa and Missouri. The conditions of 

 deposition were remarkably uniform and indicate a considerable 

 change from the turbulent and rapidly varying conditions usual in 

 the Des Moines terrane. It has been possible in this county to 

 accurately map the coal-bearing area and a section from Ottumwa 

 southwest indicates the probable presence of lower coal beds, a fact of 

 considerable economic import. The Pleistocene problems are much 

 the same as in Warren and Washington counties and the beds present 



are the continuations of those described in those counties. 



H. F. B. 



MonoclDiic Pyroxenes of New York State. Heinrich Ries. (Cont. 



Min. Dept. Columbia Univ., Vol. VI, No. 6; Annals New York 



Acad. Sci., Vol. IX, pp. 124-178, pis. XIII-XVI. New York, 



1896.) 



The pyroxenes of New York occur in the following conditions : 



(i) as primary constituents of igneous rocks ; (2) along the contact 



zones between the limestones and intrusive rocks ; (3) in crystalline 



limestones in areas of regional metamorphism ; (4) associated with iron 



ore bodies. The present paper includes results of crystallographic, 



chemical and optical investigations of all the monoclinic pyroxenes of 



the state, with the exception of Wollastonite. The crystallographic 



forms found to occur are few in number, but the combinations and the 



relative development of the faces are in most instances quite character- 



