SILURIAN OF THE LAKE-DISTRICT. 



881 



grits, of no great thickness 

 and apparently unfossilife- 

 rous ; (b) a middle series of 

 calcareous, flaggy, fossilife- 

 rous grits, of a blue colour 

 and weathering to a rust- 

 brown (this subdivision is 

 about as thick as the subdi- 

 vision a) ; (c) an upper 

 series of gritty flags, of bluish 

 or greyish colour, weathering 

 green, finely laminated, and 

 containing few fossils (this 

 series is of great thickness, 

 forming, indeed, more than 

 half the thickness of the 

 whole of the Coniston-flag 

 series ; but nevertheless the 

 lithological characters of the 

 beds fully warrant these di- 

 visions, which are borne out 

 by the fossils). For the lower 

 division of the flags I propose 

 to retain the term Brathay 

 Flags of Prof. Sedgwick, as 

 they are excellently exhibit- 

 ed in the Brathay quarry. 

 Moreover, at the time when 

 the term " Brathay Mags " 

 was proposed, it seems to h ave 

 been applied to these beds, as 

 the relations of the higher 

 beds were somewhat obscure 

 (c/. also Cat. Camb.& Sil.Foss. 

 of Woodw. Mus. p. 78). 



To the middle subdivision 

 of the higher division the 

 termColdwell beds was given 

 by Prof. Sedgwick, and this 

 name was used for the same 

 beds by Mr. Aveline (Mem. 

 Geol. Surv. 98 N.E. p. 8); 

 but as this subdivision is evi- 

 dently connected with the 

 subdivisions above and below 

 it, the term might well be 

 extended to include the 

 three, all well exposed near 

 Coldwell quarry. 



The following section(fig.2) 

 shows, on an approximately 



true horizontal scale, the e- 

 lations of these beds. 



Q.J.G.S. No. 136. 



N.W. 



-Pull Beck. 



Road from Ambleside 



to Coniston. 

 -S.E. 



Brathay Quarry. 

 -5°W. ofH". 



-Hog-House Beck. 



•Coldwell Quarry. 



era" 

 to 



&> 



"3" 



Quarry 200 yards S. of 

 Coldwell Quarry. 



-Road. 



-Dan Beck. 



-Spicka Lane. 



_.— 50 E , f g. 



2p 



Side of Latterbarrow. 



3n 



