462 PROF. E. J. GARWOOD OX THE LOWER CARBONIFEROUS [DeC. I912, 



eastern districts and occur chiefly at a definite stratigraphical 

 level — the Brownber Pebble-Bed. This bed has proved of great 

 value in determining the exact horizon of the lowest Carboni- 

 ferous deposits in the Westmorland Pennine District. In the 

 Kendal District, layers of china-stone occur locally near the base 

 of the sub-zone, crow^ded with Calcisjyherce and allied forms. 



Fauna. — In these beds fossils are usually scarce, and many of 

 the dun limestones and dolomites are apparently unfossiliferous : 

 they contain, however, ostracoda and foraminifera. 



Of the four bands established in this sub-zone, enumerated above 

 (p. 459), the three upper bauds serve to link the lower beds of the 

 type districts with those of the Westmorland Peunines on the east 

 and with the Kendal and Grange Districts on the west ; while the 

 basal Algal Band has been traced in many of the districts. 



Geographical distribution. — This sub-zone is well deve- 

 loped along the western escarpment of the Shap and Ravenstone- 

 dale Districts, where it reaches a maximum thickness of about 

 300 feet. At Meathop, in the Arnside District, about 80 feet of 

 these beds are present, and contain a coral fauna of special interest. 

 Their distribution in the Kendal, Grange, and Furness Districts is 

 shown in dark green on the accompanying maps (Pis. LIII-LY). 

 In the Westmorland Pennines, and at Lupton Eow in the Kirkby- 

 Lonsdale District, only the higher portion of this sub-zone has 

 been met with. 



(6 3) The Productus-gloiosus and RliynchoneJla- 

 faiucettensis Band. 



The algal layer at the base of this band is of great interest, 

 and is best developed in the Shap and Ravenstonedale Districts. 

 It consists of a layer of shaly dun-coloured dolomite a few feet 

 thick, in which are embedded dark calcareous nodules of a 

 compact porcellanous texture weathering to a pale grey. These 

 nodules average from 1 to 2 inches in diameter, and represent 

 the thalli of calcareous algae (see PI. XLYII, fig. 2). In the 

 district between Fawcett Mill and Ravenstouedale village, this shale 

 is underlain by a more compact bed composed of reef-like masses of 

 alg£e, disposed in undulating layers, forming hemispherical domes 

 with intervening depressions 3 to 4 inches in diameter. At least two 

 different forms of algce appear to be present in this layer, which 

 can be traced at intervals between Shap Abbey and Ravenstonedale. 

 It occurs also at the same horizon in the Kendal District; at 

 Meathop in the Arnside District; and in the outliers between 

 Kendal and Kirkby Lonsdale. It is of especial value for the 

 correlation of the beds, in districts where Productus glohosus itself 

 has not been found. 



The Productus-glohosus Band marks a constant horizon 

 throughout the Shap and Ravenstonedale Districts. It is not, 

 however, clearly traceable in the districts to the west, and in the 



