THE 



GEOLOGICAL MAGAZINE. 



NEW SERIES. DECADE V. VOL. VIII. 



No. IV. — APRIL, 1911. 



I. — Notes on British Dinosaurs. Part IV : Stegosaurus psisous, 



sp. NOT. 



By Baron FRANCIS NOPCSA. 



(WITH NINE ILLUSTBATIONS IN THE TEXT.) 



(Concluded from the March Ntimber, p. 115.) 



Limb -hones. — Since the humerus is known in Hylceosaurus (?) r 



Omosmcrus, and Stegosaurus, it is quite easy to compare the humerus 



of our new species with that of the other genera mentioned. Whether 



the shaft is hollow as in Omosaurus or solid as in Stegosaurus, cannot 



he ascertained without breaking the specimen ; the outline of the new 



humerus is, however, that of Omosaurus, not that of Stegosaurus. 



Fig. 4. Humerus of St. prisons. a: Posterior view of proximal end. 

 b. Anterior view of distal end. 



The proximal condyle was situated, as far as can be made out, much as 

 in 0. armatus, and the radial crest shows also the same curve as in 

 this species; the anconeal ridge, however, is more strongly developed, 

 and ends distally in a broad rugose area somewhat above the middle 

 of the bone (Pig. 4a). The anconeal depression and the trochlear 

 groove (visible in Pig. 4b) are less marked in St. priscus than in 

 0. armatus. The ridge for the supinator is broken off in the new 

 specimen, but if preserved it would give to the distal part of the bone 

 a rather dilated aspect, and thus produce a certain resemblance to 

 St. ttngulatus. 



DECADE V. — VOL. VIII. — NO. IV. 



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