LIFE-ZONES IN THE BRITISH CARBONIFEROUS ROCKS. 229 
seen at Instow, where in a bed of calcareous bullions the following 
fossils occur :— 
Gastrioceras listeri, Mart., sp. Pterinopecten papyraceus, Sow., sp. 
; carbonarium, Vv. Buch. Posidoniella levis, Brown., sp. 
Dimorphoceras gilbertsoni, Phill. Celacanthus elegans, Newb. 
Orthoceras sp. Hlonichthys aitkeni, Traq. 
The fauna is one which I regard as characteristic of the marine part 
of the Gannister Series of the Lower Coal Measures. 
The beds above the Instow series have a wonderfully familiar appear- 
ance to one acquainted with the Coal Measures, and I am glad to say 
that Mr. E. Newell Arber has read a paper at the Royal Society which 
conclusively proves from the flora contained in them that the Culm- 
bearing series round Bideford is of Middle Coal Measure age. 
This is borne out by the occurrence of Carbonicola acuta at Roberts 
quarry, near Bideford, immediately above a rich plant bed, with well- 
preserved Middle Coal Measure ferns. It must remain at present an 
open question whether the Carboniferous Limestone is represented in the 
Culm series by a few feet of calcareous shales and a band or two of 
limestone, which is seen on the foreshore near Fremington Station. The 
limestone also being exposed at Fremington Pill Quarry is open to 
question. The shales on the foreshore contain species of Brachiopoda, 
which are common to the Upper Devonian and Lower Carboniferous. 
There are, therefore, four life-zones in the Culm— 
Zone of Carbonicola acuta and Zone of Posidonomya becherv. 
Middle Coal Measure plants. »  Prolecanites compressus. 
Zone of Gastrioceras listeri and 
G. carbonarium. 
which definitely fix the age of the Culm of North Devon. 
This fossil evidence is of importance from an economic view, for it 
definitely shows that the beds of Culm are the representatives of the 
coal seams, and that any occurrence of coal in Devonshire is altogether 
improbable. 
The line of strike of the Mendip anticlinal and the Coddon Hill 
series have a similar relation to each other that the Carboniferous Lime- 
stone of Cork and Killarney has to the Devonian Carboniferous succession 
of the Old Head of Kinsale and Coomhola, and the absence of Carboniferous 
Limestone south of a fairly definite line is noticed in Devonshire and 
South-west Cork and Kerry. This condition of things points to a 
similarity of physical causes in both areas. 
An important paper by Mr. Vaughan, F.G.S., ‘On the Paleontological 
Sequence of the Carboniferous Limestone of the Bristol Area,’ was read 
before the Geological Society in June. The paper is not yet published, 
and I hesitate to criticise it ; but in any Carboniferous area with which 
IT am acquainted the fossils chosen by Mr. Vaughan as denoting zones 
and sub-zones—with one exception, that of Modiola lata, a variety 
probably of M. macadami—all occur together at several horizons. 
To quote 3.— Productus semireticulatus, P. cora, Schizophoria 
resupinata, and Spiriferina octoplicata occur practically at all horizons in 
the same beds. 
It is, however, a subject of congratulation that work is being com- 
menced on palzontological lines in the Bristol and Mendip area. 
The zonary divisions established by Mr. Vaughan are given in the 
following table. (This is the form in which these divisions are finally set 
out after emendation and further revision of a preliminary working system.) 
