LIFE-ZONES IN THE BRITISH CARBONIFEROUS ROCKS. 239 
Gin Mine Coal. Permission to cut a trench for this purpose on their 
estate near Smallthorne was kindly given by Messrs. R. Heath & Co., to 
whom we are under great obligation. Our thanks are also due to Mr. 
W. Lockett for assistance and advice. 
The horizon was reached and its relation to the coal seam, and also its 
succession of life-forms, exactly made out. This was of great importance, 
since our previous conceptions required inversion. It was rather dis- 
appointing, however, to find the richest part of the horizon, consisting of a 
very impure and earthy limestone, to be so decomposed on the hillside, 
where we were working, that the fossils were incapable of preservation, 
and often of identification. So that the proposal to work the bed on a 
larger scale at this point was abandoned. The general section is shown 
in fig. 4, and the following is the succession of the measures constituting 
the ‘ marine bed,’ together with the fossils restricted to each stratum, so 
far as could be ascertained, viz. — 
ft. 
(1) Dark shale 
(2) Impure limestone é : : ; Fe 
(3) Dark shale . : : , ‘ : 2 oy hi 
Cons 
(1) contains— 
Lingula mytiloides, Discina nitida. 
(2) contains— 
Productus semireticulatus, Athyris ambigua, Chonetes Laguessiana, Nucula 
gibbosa, Ephippioceras costatum, Raphistoma junior, Plewronautilus armatus, Pleuro- 
nautilus n. sp. (with tubercles). 
(3) (upper layer) contains— 
Archeocidaris Urei, crinoid ossicles, Loxonema sp., Turbonellina, cf. 7. formosa, 
Orthoceras pygmaeus, Pseudamusium jfibrillosum, Nuculana acuta, Ctenvdonta 
levirostris. 
At base :— 
Pterinopecten papyraceus, Posidoniella sulcata. 
In South Wales collecting was done on the northern outcrop of the 
Carboniferous rocks, and the opportunity was taken of examining the 
‘patchworks’ of the Coal Measures in that district. There is no doubt 
that great discrimination and experience are required in collecting from 
‘patchworks,’ and serious errors have arisen in the past from the work of 
spoil-heap collectors. This is the more to be regretted, since in no other 
circumstances do we find such a quantity of material available for search 
and inspection. 
Owing to the personal uncertainty as to the name of the coal seam 
from whose associated measures the fossils have been derived the position 
of the ‘ patch’ where they were found will be given in terms of latitude 
and longitude picked off the 1-inch Ordnance maps, so that the localities may 
ae assistance to other workers. The horizons will be taken in descending 
order. 
A few feet below the outcrop of the Soap-vein on the patchworks, 
