-4 MR. E. A. NEWELL ARBER OX THE UPPER [Feb. ICJOJ, 



Goniatites are, as a rule, extremely common in the calcareous 

 nodules, and they also occur in the Mouthmill Limestone. By far 

 the most abundant species is Gastrioceras carbonarium (von Buch), 

 which is found apparently throughout the Upper Carboniferous 

 sequence in Devon and Cornwall, while Dimorplwceras Gilbertsoni 

 (Phill.) is also frequent. Gastrioceras Listeri (Martin) is rarer. 

 The lamellibranch Pterinopecten papyraceus (Sow.) is common, 

 and ofteu associated with the more abundant species of goniatites. 

 A similar association is found in the Midland Coalfields. 1 There 

 are indications that other genera occur, though perhaps less 

 frequently. Ortlioceras sp. has been obtained at Mouthmill, and 

 from Hescott Quarry near Hartland. A typical fauna is found in 

 the Mouthmill Limestone and the associated shales with calcareous 

 nodules, which is as follows : — 



Gastrioceras carbonarium (von Diniorphoecras G'tfherttoni (Phill.). 



Buch;. Orthoceras sp. 



Gastrioceras Listeri (Martin). Pteri/wpecten papyraceus (Sow.). 



The same species were described by Hall 2 from Instow, in JSorth 

 Devon, in 1876. 



Badly-preserved shells, possibly allied to Posidoniella. were found 

 in a rolled nodule on the beach north of Bude. In some sandy, 

 nou- calcareous nodules at Hescott Quarry, a Myalina, possibly 

 31. compressa, Hind, was obtained, and other genera are probably 

 represented. I am indebted to Dr. "Wheelton Hind, F.G.S., for 

 several of these determinations, and to Mr. G. C. Crick, E.G.S., of 

 the British Museum (Xatural History), for assistance in naming 

 the cephalopoda. 



The freshwater mollusca appear to be much more restricted in 

 Devon than the marine forms. The impure, lenticular limestone- 

 bands of the Bideford district have not yielded any shells of either 

 type so far. But, in the shales associated with the culm-bands, 

 specimens of Carbonicola acuta (Sow.), and possibly also C. aquUina? 

 (Sow.), have been found at Bideford, as I have already recorded. 3 

 Mr. Rogers has since discovered other shale-beds containing this 

 genus on the coast at Greena cliff, and at Summer Hiscott in the 

 parish of Tawstock ; in both cases in close proximity to the culm- 

 bands. 



VII. Gexeral Coxcixsioxs. 



The fact that by far the larger portion of the Carboniferous 

 rocks of Devon and Cornwall is of Upper, and not of Lower 

 Carboniferous age, as has been commonly supposed, was emphasized 

 by the study of the fossil flora of the beds of the Bideford district 

 in my paper published in 1904. The present enquiry has served 

 to confirm this conclusion, by bringing into consideration evidence 

 of a wider nature. The discovery of Upper Carboniferous faunas, 



1 See Stobbs & Hind (05). 



3 Hall (76). 



' Arber (04) p. 319. 



