392 



CRETACEOUS. 



Feet. In. 

 Greyish marly sand, with nodular concretions. Exogyra conica, 



E. hvvigata 3° *^ 



Sands, with green earth (argillaceous). Inoceramiis si/lcafiis 25 o 



Greenish-grey sands and grit-bed. Exogyra conica {^P^erniicn- 



laria concava) 3 6 



The beds 1-9 are grouped as Upper Greensand and Gault by Mr. Meyer, the 

 Blackdown beds being regarded as the equivalents of beds I-4, including Gault and 

 base of Upper Greensand. The beds 10 to 12 are all grouped as Chloritic Marl by 

 Mr. Meyer, but the term should be restricted to bed No. 12. ^ The Warminster 

 beds are grouped as equivalent to beds 10-12. but Mr. Jukes-Browne has 

 questioned the propriety of this correlation, for the Warminster beds are below the 

 Chloritic Marl.- 



FiG. 65. — Section at Snowdown, Chard. 



4. Chalk (13 feet shown) ] Lower Chalk. 



3. Chloritic Alarl, i foot to 18 inches, j 



2. Calcareous Sandstone, with quartz grains, 7 feet 8 inches") Uppg^ Greensand. 



I. Chert Beds (15 feet shown). J 



The Greensand of the neighbourhood of Chard consists in its 

 upper part of calcareous sandstone and chert beds (20 to 30 feet), 

 and lower down of sands of varied hue, green, brown, and yellow 

 (about 120 feet). The topmost beds of calcareous sandstone or 

 grit generally crop out in the roads and lanes and along the scarps 

 of the hills. (See Fig. 65.) At Dalwood, north of Axminster, the 

 sands yield Exogyra conica, Pectcn orbicularis, etc. 



The nodules of chert frequently weather sandy on the exterior, and they may be 

 found exhibiting only a small internal nucleus of chert ; while sandy concretions 

 may be obtained near Honiton, which appear to exhibit the formation of chert 

 from a centre. 



Near Widworthy (at the base of the Chalk), according to Dr. Fitton, there is a 

 siliceous bed called ' Grizzle ' by the quarrymen, about five feet in thickness, and 

 containing greenish particles. It has been much used for building-purposes. 



1 See also H. G. Fordham, P. Geol. Assoc, iv. 515. 



- G. Mag. 1877, p. 358. See also Barrois, Ann. Soc. Geol. du Nord, iii. 7. 



