290 Dr. Francis Baron Nopcsa — British Dinosaurs. 



Since a detailed description of Streptospondyliis is far beyond the 

 scope of this paper, I intend to publish such a description in the 

 Beitrdge zu Geologie iind Palaeontologie (Vienna), and here, in 

 accordance with my previous Notes on British Dinosaurs, only the 

 most salient points will be mentioned. First of all, it has to be 

 remarked that Mr. Parker's fossil indicates a much smaller and, as 

 the structure of the sacrum shows, a more immature individual than 

 that in the Paris Museum. 



The shnll, which is altogether missing in the Paris specimen, is 

 nearly complete in the Oxford individual, but in consequence of 

 being imperfectly freed from the matrix I could only identify 

 maxillary, prfemaxillary, dentary, basis cranii, and quadratum. The 

 greatest possible disproportion is to be remarked between the facial 

 and the cerebral region. Tlie huge jaws are built after the Megalo- 

 saurus pattern, and the same is also true with regard to the long, 

 compressed, trenchant, and serrated teeth. There exist two, perhaps 

 even three, anteorbital apertures, as in Creosaiirus and Megalosaurus, 

 while in Ceratosaiinis there is only one. The quadratum is relatively 

 short and points to the existence of a Greosaurus-lihe quadrato- 

 squamosal arch. The short basis cranii shows a strong transverse 

 expansion of the brain in the region of the vagus nerve. The 

 brain-cavity was a good deal larger than the neural canal in the 

 sacral region, and its large size ^ is easily explained by the com- 

 paratively high intelligence that Streptospondyliis must have possessed 

 as an agile carnivorous reptile. Tubera basi-occipitalia seem to be 

 wanting. The diameter of the ball-like occipital condyle cannot 

 have exceeded 2"5 cm. 



Vertebr<B. The foremost cervical vertebrte are remarkable for 

 their small size, the centra being only 4 cm. long and 2-5 cm. high, 

 while the posterior cervicals attain 6-0 and 3*5 cm., and some dorsals 

 even 8 and 4-5 cm. The neural spines are but feebly developed ; the 

 arch shows, much like the primitive Sauropoda, a complex system 

 of diapophysial, oblique, pra^zygapophysial, postzygapophysial, and 

 horizontal laminae, and differs in consequence from all the other known 

 Theropods. The centra of the cervical vertebrae are unlike those of 

 Geratosaurus, Greosauriis, and the Triassic Theropods, strongly convex 

 in front, deeply concave behind, and show large pleurocentral foss^. 

 In the dorsal vertebrae the antero-posteriorly blade-like neural 

 spines are better developed than in the cervicals, the arch is 

 again supported by different laminae, and the centra pass from a 

 convexo-concave to a plano-concave and further on to a nearly 

 biconcave stage. As we pass backward along the dorsal region the 

 pleurocentral cavities become gradually less pronounced, so that in 

 the posterior dorsals they are altogether wanting. The centra of 

 the sacral vertebra, though united in the Paris specimen, are free 

 in the Streptospondylus in Mr. Parker's collection and show here 

 saddle-shaped intersacral articulations. 



1 I am fxilly aware this expression seems a euphemism when one thinks of modem 

 reptiles, but it is not so when one thinks of such vegetable-feeders as Stegosaurus or 

 Triceratops. 



