C. S. Garnett—Alteration of Shales in Derbyshire. 473 
EXPLANATION OF PLATE IX. 
Photograph of camera lucida drawings of Foraminifera. All figures are 
magnified 30 diameters. 
Fics. 
1.—Nodosaria seminuda Reuss. Hartwell Clay, Hartwell. 
2.—N. (Gl.) humilis Roemer. Hartwell Clay, Long Crendon. 
3.—N. (Gl.) humilis Roemer. Hartwell Clay, Hartwell. 
4.—Vaginulina incompia Reuss. Hartwell Clay, Hartwell. 
5.—Frondicularia concinna Reuss. ‘‘ Kimmeridge Clay,” Wheatley. 
6.—Vaginulina discors Koch. Hartwell Clay, Hartwell. 
7.—V. harpa Roemer. Hartwell Clay, Long Crendon. 
8.—Cristellaria Roemeri Ruess. Hartwell Clay, Hartwell. 
9.—C. fragraria Giimbel (short form). Hartwell Clay, Long Crendon. 
10.—C. fragraria Giimbel (long form). Hartwell Clay, Hartwell. 
11.—Thurammina albicans Brady. Hartwell Clay, Hartwell. 
Norr.—A series of specimens is deposited in the Bucks County Museum, 
Aylesbury, and therefore only a few of the more characteristic forms are 
figured here. 
On a Local Alteration in Limestone Shales at 
Wensley, Derbyshire. 
By C. 8. GaRNerr. 
SMALL stream forms the boundary between the Parishes of 
Wensley and Winster, on the north-west of the former; and here- 
abouts its bed, in the Limestone Shale, is probably about 30 feet 
above the Carboniferous Timestone. On the Winster side, the 
shales form a wooded slope (Whites Wood) rising 100 feet in about 
900 feet, and on this side the shale is quite normal and of the 
black colour usual in the lower beds of this formation. On the 
Wensley side the ground rises more gradually, and the actual bank 
of the stream averages not more than about 10 feet in height. Here, 
an altered shale is exposed and can be traced (through the activity 
of moles) in the fields behind. 
There appear to be two small areas of alteration, just over 
100 yards apart ; and in the case of the larger, of a traceable area 
of about $ acre. 
At the place of the larger exposure the shale beds are thrown 
upwards and lie in a confused manner—not unlike the upward 
bursting caused by the weight of hills behind. On this (the south) 
side the ground gradually rises from just under 500 feet at the 
level of the stream, to 1,000 feet in just under half a mile; on the 
opposite side it rises to 80G feet in a quarter of a mile. 
In the areas under consideration the shale in its upper beds, 
instead of being black in colour, appears bright brick-red from a 
little distance, and on closer examination is found to be almost 
white or of a buffsh tint within the lamin, whilst at the surface 
of these it is quite bright red. This distribution of colouring 
matter is best seen in the harder portions; where the shale was 
softer the redness is more evenly distributed in the clay, but the 
red colouring matter is in places almost or quite absent. The 
lack carbonaceous matter has been completely removed, and 
