98 The Ottawa Naturalist. [December 



from this road corner westward across the farm lands, the following 

 section was measured approximately, with a Locke level : 



Base of cherty Richmond. 



Interval, upper part consisting of argillaceous 



Richmond, lower part not exposed 57 ft. 



Very coarsely granular limestone 5 ft. 



Clay shale with some indurated clay layers and 



some very thin limestone layers interbedded 21 ft. 



The clay shale here mentioned contains Bollia permarginata, at 

 various levels. Clidophorus noquettensis and Rafinesquina alternata- 

 varicosa occur chiefly in the five-foot limestone section. 



Three-quarters of a mile south of the Stratton store the base of the 

 cherty Richmond is 32 feet above the level of the bay; directly west 

 of the Stonington post office this interval is 23 feet, and at the Skaug 

 Brothers store it is 19 feet. The dip evidently is southeastward. 



The greatest thickness of the cherty Richmond known at present 

 is 14 feet, and this is exposed directly west of Stonington post office, 

 but the top of this part of the Richmond is not exposed here, so that its 

 total thickness is unknown at present. Only the upper part of the 

 underlying argillaceous Richmond was readily accessible at the time 

 of my visit. This presented the following section at the home of 

 Andrew Rheinholdson, three-quarters of a mile south of the Stratton 

 store : 



Cherty Richmond, cream-colored limestone 5.5 ft. 



Argillaceous Richmond, abundantly fossiliferous, 

 and readily accessible. At the very base of 

 the section Streptelasma ( ? ) divaricans and 

 Strophomena sulcata were collected, and at the 

 very top Dinorthis subquadrata occurred. 

 Thickness 11 ft. 



Indurated clay layer, spalling off in larger 

 masses, containing Pholadomorpha pholadi- 

 formis and specimens related to Modiolopsis 

 concentrica 2 ft. 



Fossiliferous grey-blue argillaceous limestone 

 carrying the same fauna as the overlying 

 layers 6 ft. 



Directly west of Stonington post office, the Pholadomorpha layer 

 is 16 feet below the base of the cherty limestone, and only 5 feet above 

 the bay. At no locality were the exposures below the Pholadomorpha 

 layer well exposed for collecting and practically all the fossils de- 

 scribed from the argillaceous Richmond were obtained above the level 

 of this layer. 



