﻿398 



MR. L. EICHARDSON ON THE RH^TIC AND [Allg. I905, 



small anticline running rather south of east, and are traversed by several small 

 faults, all probably branches from the Coldknap Fault.' 



A sketch-section is given by Mr. Strahan {op. cit. p. 64). 

 the O.s'tfrm-limestones are the following beds : — 



Beneath 



Thickness in feet inches. 

 Paper- Shales. 

 ( Marl,bluish-grey , with harder bands 5 



I Calcite-layer 



| Band of indurated marl 



A. ■{ Marl, bluish-grey 



Layer composed of the valves of an 



Ostrea 



l v Marl, bluish-grey 2 



B. Limestone in two beds, bluish -grey 



weathering yellow. The lower 

 bed in particular resembles the 

 Sun-Bed, and exhibits a con- 

 choidal fracture 







/ 1. Shales, bluish-grey, calcareous. 

 Bubbly limestone, with more 

 compact limestone imme- 

 diately below, weathering 

 yellowish. Fossils most 

 abundant in the upper 

 portion 



3. Shale 



cm 



4. Limestone, yellowish 







V 



I I 



5. Shale, blue and yellow, in- 



durated 



6. Gritty layer 



7. Shale, greenish -grey, thinly 



laminated 



8. Limestone, blue-centred 



9. Shale, greenish-grey ... about 

 10. Grit, pyritic, ripple-marked : 



to 3 inches 



6 Modiola minima, Moore 

 0| \iion Sowerby. 



2 • 



2 Ostrea sp. 

 10 



fPlicatula intus-striata, 

 PI. hettangiensis, and 

 Lima (Plagiostoma) 

 vaioniensis, common ; 

 5 \ Protocardium Philip- 

 pianum, Pleuropho- 

 rus(?J, Modiola mini- 

 ma (?) (large) Moore, 

 9 \^ Ostreasp.; anostracod. 

 ( Pleurophorus (?) & Pro- 

 \ tocardium (?) as casts, 

 1^] Plicatula intus- 

 y striata. 

 q f Lima (Plagiostoma) 



\ vaioniensis. 

 9 I Shell-debris ; Plicatula 

 ~* \ intus-striata. 



Upper Rustic. 4. Shales, greenish- grey. 



The White-Lias Beds (C) in the foregoing section are extremely 

 fossiliferous, and it is remarkable that they have not attracted 

 attention on this account. The strata between the Paper-Shales 

 and the Upper fthsetic marl or shales (4) at Lavernock measure 

 8 feet IO5 inches, and at Barry 12 feet 3| inches, the increase in 

 thickness at the latter locality amounting therefore to close upon 

 3 feet 6 inches. 



Mr. H. B. Woodward has observed a bone-bed in crevices of the 

 top-bed of marl, at the base of the Black Shales at Cadoxton. 1 



1 Proc. Geo!. Assoc, vol. x (1888) p. 531. 



