44 Reports and Proceedings— Geol. Soc. Lond. 



the remains of small Crocodiles were detected in considerable abun- 

 dance ; and he gave a description of these, and especially of one 

 which he named Theriosuchus pusillus. This reptile, which is esti- 

 mated to have been about 18 inches long, had scutes presenting the 

 " peg and groove " character of those of Goniopholis, with which 

 genus it further agreed by having the antorbital part of the skull of 

 the broad-faced Alligator type. In the dentition it resembled the 

 Triassic Theriodonts more than any other Crocodiles. The vertebras 

 are amphiplatyan. In conclusion, the author indicated the con- 

 ditions which have to be fulfilled in the case of recent Crocodiles to 

 enable them to drown a large mammal without inconvenience to 

 themselves, and showed that these conditions were realized also in 

 the Neozoic forms, whilst there was no reason to suppose that any 

 Mesozoic Crocodiles possessed the adaptations in question. 



II.— Nov. 20, 1878.— E. Etheridge, Esq., F.R.S., Vice-President, 

 in the Chair. — The following communications were read : — 



1. " On the Upper-Greensand Coral Fauna of Haldon, Devon- 

 shire." By Prof. P. Martin Duncan, M.B. Lond., F.R.S., F.G.S., etc. 



The author in this paper stated that since the publication of his 

 supplement to the British Fossil Corals, published by the Palaeonto- 

 graphical Society, several new corals have been obtained at Haldon by 

 Mr. Vicary, of Exeter. Twelve additional species were noticed, of which 

 ten were new. This brings the total number of species in the Haldon 

 Greensand up to twenty-one. The new species are thus distributed : 

 — Aporosa: Oculinidge (1), Asteeidee (8), Fungidse (5); Perforata: 

 Turbinarige (2) ; Tabidata (1). The paper concluded with remarks 

 on the genera and species represented, from which it appeared that 

 the Coral fauna of Haldon is the northern expression of that of the 

 French and Central European deposits, which are the equivalents of 

 the British Upper Greensand. The Haldon deposit was formed in 

 shallow water, and the corals grew upon the rolled debris of the age. 



2. " Notes on Pleurodon affinis, sp. ined., Agassiz, and description 

 of three spines of Cestracionts from the Lower Coal-measures." By 

 J. W. Davis, Esq., F.G.S. 



The author described some fossil remains of fish obtained from 

 the bone-bed immediately above the " Better-bed Coal " referred to 

 by him in a former paper (see Q. J. G. S. vol. xxxii. p. 332). The 

 fossils described included Ichthyodorulites belonging to 4 species, 

 namely : — Plenrodus affinis, a species named, but not described or 

 figured, by Agassiz ; Hoplonclius elegans, gen. et sp. nov. ; Ctena- 

 canthus cequistriatus, sp. nov. ; and Phricacantlius biserialis, gen., et 

 sp. nov. Teeth, believed to be those of Pleurodus affinis, were also 

 described. 



Specimens anything like perfect are very rare. He suggested 

 that the coal, after having been formed on land, probably became the 

 bed of a lake or an open shore-line. He remarked that this thin 

 bed extended uniformly over a very considerable area. In reply 

 to Prof. Morris, he stated that the Geological Survey had adopted 

 a different line of division between the Middle and Lower Coal- 



