﻿Vol. 66. ] MEGALOSAURUS BRADLEY! . Ill 



5. Ow a Skull of Megalosaurus from the Gkeat Oolite of 



Minchinhampton (Gloucestershike). By .Arthur Smith 



Woodward, LL.D., F.R.S., Sec.G.S. (Read January 26th* 



1910.) 



[Plate XIII.] 



Although the carnivorous Dinosaur Megalosaurus was first dis- 

 covered in the Stonesfield Slate nearly 80 years ago, and is now 

 represented by numerous fossils from the Bathonian and later 

 Mesozoic formations of England, its skull has hitherto been known 

 only by unsatisfactory fragments of jaws. 1 Our acquaintance with 

 the Megalosaurian type of skull has depended solely on discoveries 

 of nearly complete specimens in the Jurassic and Cretaceous 

 formations of North America. 2 At last, however, Mr. F. Lewis 

 Bradley, E.G.S., has been able to submit to the Society the greater 

 part of a skull obtained some time ago from the Great Oolite in an 

 excavation for a reservoir at Minchinhampton (Gloucestershire) ;, 

 and he has prepared the specimen with so much skill and success 

 that it is beautifully exposed for study from the left side (PI. XIII,. 

 fig. 1). It is rather small, measuring only 26 centimetres in total 

 length, but there cannot be much doubt that it belongs to the genus- 

 Megalosaurus itself. 



The upper portion of the fossil is unfortunately destroyed by an 

 irregular fissure in the rock, which is partly filled with calcite. The 

 cranium is, therefore, scarcely seen ; but there are traces behind of 

 the occiput, which is somewhat deeper than wide above the foramen 

 magnum, and lies in a plane inclined much forwards. The external 

 bones of the temporal region and face are remarkably thin and' 

 delicate, and in their crushed condition it is difficult to distinguish 

 the sutures between them. The large vacuities, however, which 

 form so conspicuous a feature in the American Megalosaurian 

 skulls, are very clearly defined, and their boundaries are probably 

 not distorted. The lateral temporal vacuity (T.) is narrow and' 

 deep ; the orbit (0.) is wider, with a gently curved lower margin, 



1 W. Buckland, ' Notice on the Megalosaurus' Trans. G-eol. Soc. ser. 2, vol. i 

 (1824) p. 390 & pis. xl-xli ; T. H. Huxley, ' On the Upper Jaw of Megalosaurus 

 Quart. Journ. Geol. Soc. vol. xxv (1869) p. 311 & pi. xii ; J. Phillips, ' Geology 

 of Oxford, &c.' 1871, p. 197 & diagrs. lvi-lvii ; R. Owen, ' On the Skull of 

 Megalosaurus ' Quart. Journ. Geol. Soc. vol. xxxix (1883) p. 334 & pi. xi. The 

 so-called brain-case of Megalosaurus described by F. von Huene (Neues Jahrb. 

 1906, vol. i, p. 1 &pl. i) from the Stonesfield Slate was found isolated, and now 

 appears to be more likely referable to Cetiosaurus than to the former genus. 



2 See especially O. C. Marsh, 'The Order Theropoda ' Am. Journ. Sci. 

 ser. 3, vol. xxvii (1884) p. 330 & pis. viii-ix ; H. F. Osbora, ' The Skull of Creo- 

 saurus' Bull. Am. Mus. Nat. Hist. vol. xix (1903) p. 697, with text-figs., and 

 ' Tyrannosaurus, Upper Cretaceous Carnivorous Dinosaur ' ibid. vol. xxii (1906) 

 p. 281 & pi. xxxix ; O. P. Hay, ' On certain Genera & Species of Carnivorous 

 Dinosaurs, with special reference to Ceratosaurus nasicornis, Marsh ' Proc. 

 U.S. Nat. Mus. vol. xxxv (1908) p. 351, with text-figs. 



Q. J. G. S. No. 262. i 



