Vol. 54.] IN THE CARBONIFEROFS LIMESTONE OF DEEBTSHIRE. 175' 



size of the crystals varies from -5 x "15 mm. to '15 X '05 mm. 

 Two often penetrate each other at right angles, forming a 

 penetration-twin. 



No. 434, sp. gr. 2-64, about 1 foot from No. 425. A foraminiferal 

 limestone, containing numerous quartz-crystals in bipyramidal 

 prisms. Some of these contain a small quantity of calcite, which 

 in one case is arranged zonally. Many of the foraminifera are 

 penetrated by quartz-crystals, which fact proves that the quartz is 

 later than the organisms and therefore of secondary growth. The 

 residue consists entirely of quartz-crystals, which sometimes 

 penetrate each other at right angles. They vary in size from 

 •80 X '20 mm. to -10 X -0375 mm. 



No. 745, a few feet from No. 434, is a piece of white limestone 

 surrounded by and embedded in the darker quartz-rock. It 

 consists of foraminifera, fragments of organisms, and a small 

 quantity of crystalline calcite. Yery few quartz -crystals are present. 

 The residue consists of quartz-crystals, which vary in size from 

 •30 X -10 mm. to •lO x "025 mm. 



No. 744, about 20 feet from No. 434, but on the opposite side of 

 it to No. 745. This is from a small outcrop of limestone, which is a 

 few feet from one of the quartz-rocks, and separated from it by grass. 

 It is a limestone containing foraminifera and other organisms. 

 There is a large number of quartz-crystals present. The residue 

 consists entirely of quartz-crystals, varying in size from '80 X •20 mm. 

 to '15 X '05 mm. Two often penetrate each other at right angles. 



The preceding specimens are from about the same horizon, 

 assuming the rock originally to have had the same dip as the 

 ordinary limestone above it in the same field. 



The following are from a higher horizon : — 



No. 741. A foraminiferal limestone, with very few quartz- 

 crystals and fragments of organisms. One foraminifer is pierced 

 by a crystal of quartz. The small amount of residue consists only 

 of quartz-crystals, always separate, varying in size from '40 x 

 •125 mm. to -05 x '025 mm. 



No. 742, near No. 741. A foraminiferal limestone, with few small 

 quartz-crystals and some crystalline calcite. The residue consists 

 of quartz-crystals, varying in size from ^25 x '05 mm. to "05 x 

 •0125 mm., and two or three small fragments of a non-crystalline 

 material. 



No. 743, 20 feet from No. 742, is similar to it, and contains shell- 

 fragments. The residue consists of quartz-crystals, varying in size 

 from -20 X "05 mm. to ^04 x '01 mm., and a few small pieces of 

 brown opaque material. 



(/) Moorlands Lane. 



In Moorlands Lane, near its junction with Moor Lane, about 1 

 mile north-west of Bonsall, is a small quarry in which the quartz- 

 rock has been worked.^ 



* This is probably the white chert or chiua-stone quarry mentioned by Farey, 

 * General View of Agric. & Minerals of Derbyshii-e,' vol. i (1811) p. 274. 



