70 The Ottawa Naturalist. 



" First " and " Second " " Rocky Points " the upper part of the Cat 

 Head beds are plainly seen in the lower beds of the cliff. 



UPPER MOTTLED LIMESTONE. 



Just above the yellow limestone beds, referred to as the Cat 

 Head beds, there is found a series of mottled limestones somewhat 

 similar to the lower limestone member. At the north end of the lake 

 the beds are very much harder and more dolomitic than farther south. The 

 section there is evidently much thinner, as between the base of the 

 cliffs at the first Rocky Point and the Silurian rocks at the mouth of 

 the Great Saskatchewan there can be only a very thin section which 

 must include not only the upper mottled limestone but the Hudson 

 River shales, etc. Farther to the south the section is slightly altered, 

 the lower beds of these mottled limestones resemble those to the north, 

 but higher up in the section the beds become darker in colour and are 

 there only impure earthy limestones which are evidently grading up to 

 the shales of the overlying Hudson River series. These lower beds are 

 to be found at a point about nine miles north from Clark's Point, while 

 at Clark's Point are seen the upper earthy limestones which with those 

 at the mouth of the Little Saskatchewan River, form the transition beds 

 to the Hudson River shales. The top of the upper mottled limestones 

 is thus somewhat similar in appearance and constitution to the lowest 

 member of the lower mottled and the top beds of the latter to the lower 

 beds the former. These upper beds are thus described by Dr. R. Pell* 

 as they occur on the Little Saskatchewan : 



" At tin- head of the four mile rapid there is a small exposure of thinly bedded 

 flat lying limestone; on the south side of the river and at the foot of the rapid, limestone 

 interstratificd with shale is seen on both sides of the river. It is of yellowish and 



nish grey colour and has a magnesian character. I noticed a large obscure Ortho- 

 ceras in one of the beds and collected a tolerably well preseived Pleurotomaria and a 

 Rkynchonella resembling the Hudson River form of A', uicrebescais (Hall). 



On the Fisher River the only beds seen are near the mouth and 

 they appear to be near the base of the upper mottled limestones not 

 far above the Cat Head beds. They are light coloured mottled hme- 

 stortes very much like those at East Selkirk and Lower Fort Garry. 



1 - ' .' / ' ; : ; i-1 .- - 1 ! - 



Report by Mr. R. Bell, Report of Progress, G.S.C, for 1874-5, PP- 3 s - 



