TRANSACTIONS OK THE SECTIONS. 93 



place, as constantly happens in Ceratiucark papllio, Salter, from the Upper Silurian of 

 Lesmahagow (see ' Siluria,' 4th edit. 1807, p. 230, Fossils (CK3), fig. 1, and footnote 

 thereon). The maxillse, which are preserved in situ in Dr. Scouler's specimen, 

 indicate the true anterior end of the carapace. 



New Facts hearinr/ on the Inquiry concerning Forms intermediate between Birds 

 and Reptiles. By Henry Woodward, F.B.S., F.G.S., of the British 

 Museum. 



In this paper the author drew attention to the great hiatus existing at the present 

 day between Birds and Keptiles, and referred to the researclies of Prof. Huxley and 

 others in order to show tliat both the Ornithic and Reptilian types were super- 

 structures raised on the same ground-plan, and that the Chelonia, Ichthyosauria, 

 Plesiosauria, Pterosauria, and Lacertilia differ fully as much from one another aa 

 they do from the class Aves. 



To associate all these forms together under one great Class, the Sauhopsida, as 

 proposed by_ Prof. Huxley, is therefore fully justified by the common structui-al 

 aflinities which they present. 



Among existing birds the Ratitce or Struthious birds come nearer to Reptilia than 

 any other gi-oup ; and their wide distribution attests their great antiquity, whilst 

 their fossil forms occur as low down as the Eocene. The author pointed out that 

 the Pterosauria only presented an adaptive modification of Avian structures, but 

 did nothelp to bridge over the gap which exists between these two divisions. 



He cited the remarkable Mesozoic bird (the Arch(sopte)-i/x) as aftbrding a more 

 generalized type of structure than any other known genus of Aves, the tail being 

 composed of twenty free vertebrae, and the digits of the wings being armed with 

 claws. 



Two birds had also been described by Prof. 0. C. Marsh from the Cretaceous 

 shales of Kansas, remarkable for possessing numerous teeth in both jaws, implanted 

 in distinct sockets, and also biconcave vertebraj. 



Lastly, Prof. Owen had just described a new and remarkable bird from the Lon- 

 don Clay of Sheppey, the Odontopten/x toliapicus, having very prominent denticu- 

 lations of the alveolar margins of the jaws, which, although not true teeth, no 

 doubt subserved the function of those prehensile organs. 



From the extreme rarity of all terrestrial-animal remains preserved in a fossil 

 state, it may be justly concluded that many more such archaic birds with reptilian 

 modifications actually existed in the Mesozoic epoch, although they may never be 

 discovered by geologists. 



The author then referred to the instances of fossil Reptilia which show remark- 

 able ornithic modifications — as, for example, the singular CompsognatAtis loiiffipes 

 from Solenhofen, a lizard which, from its peculiar conformation, must have hopped 

 or walked in an erect position, after the manner of a bird, to which its long neck, 

 small head, short and diminutive anterior limbs gave it an extraordinary resem- 

 blance. 



From the researches of Mantell, Owen, Phillips, Huxley, and Hulke in England, 

 Cope, Leidy, and other anatomists in America, it would appear that the huge 

 Dinosauria, the Iguanodon, Megalosaurus, &c., had also diminutive fore limbs and 

 largely developed hind limbs, whilst from the form of the pelvic bones and the 

 anchylosis oi the sacral vertebrae, there can be little doubt they walked in an almost 

 erect position — a conclusion which the bipedal tracks discovered by Mr. S. H. 

 Beckles tend to confirm. 



The author then described a remarkable lizard, the Chlamgdosaurus Kingii from 

 Australia, which habitually runs upon its hind legs, a mode of progression which 

 its disproportionately short fore limbs at once suggest as its natural position ; and 

 as its habits are known to have been observed by Mr. Gerard Krefft and other 

 naturalists, it affords a most valuable living illustration of a Mesozoic tvpe ap- 

 proaching birds on the Reptilian side, as the Struthious Birds approach reptiles on 

 the Avian side. 



Some singular tracks from Solenhofen were referred to, which must have been 



