OIST SOME DIXOSAURIAN REMAINS. 



695 



48. Note on some Dino saurian Remains in the Collection of A. 

 Leeds, Esq., of Eyebury, Northamptonshire. By J. W. Htjle:e, 

 Esq. (Read June 23, 1887.) 



In a short visit which I made with Dr. Woodward in May 1886 to 

 Eyebury to see the very rich and highly instructive collection of 

 Saurian fossils made by Mr. A. Leeds from the Kimmeridge Clay of 

 Northamptonshire, two series of remains arrested our attention by 

 the close resemblances they bore to those of the Wealden Orni- 

 thopsis, H. G. Seeley, to Omosaurus, R. Owen, and to certain of 

 the American Jurassic Dinosaurs described and figured by Prof. 

 0. C. Marsh. We had not at that time with us on the spot the 

 materials for instituting an exhaustive comparison, but on a second 

 visit to Eyebury, recently made, I took with me Sir E. Owen's 

 and Prof. 0. C. Marsh's memoirs, and with these by me I re- 

 examined the two series of fossils. The results of this renewed 

 inquiry are so interesting that I venture to bring them under the 

 notice of the Geological Society. 



Part I. — Ornithopsis Leedsii. 

 Ornithopsis, H. G. Seeley. 



Synonyms : Eucamerotus, Hulke ; Cetiosaurus, R. Owen, partim ; 

 Cetiosaurus, Phillips, partim ; Ohondrosteosaurus, B. Owen, 

 partim; Bothrospondylus,H. Owen, partim. 



The remains in Mr. Leeds's collection referable to this Dino- 

 saur, or to a very nearly allied form, comprise several vertebrae, 

 ribs, both pubes, both ischia, the right ilium, and many small 

 fragments too imperfect for reunion and identification. 



Vertebrce. — All the vertebras are, I think, referable to the trunk ; 

 they comprise four centra, and some portions of neural arches and 

 processes. All the centra are much crushed and distorted, and 

 they have lost their arches. They display the large chambers 

 opening externally in the lateral aspect of the centrum, and exca- 

 vating this latter so deeply that the chambers of opposite sides 

 nearly meet in the median antero-posterior plane of the centrum 

 under the neural canal, being separated there only by a thin, bony 

 partition, remains of which are preserved in one specimen. The 

 following measurements will give some idea of the bulk of the least 

 mutilated of four centra ; but it should be borne in mind that these 

 very imperfectly represent the dimensions of its true figure. The 

 present horizontal diameters of the two articular faces are 29 

 centim. and 28*5 centim. The same diameter taken at the middle 

 of the centrum is 19'5 centim. The length of the centrum between 

 the two articular faces, taken at the under surface, is 14 centim. 

 This surface is much incurved in the longitudinal direction, which, 

 gives the centrum the appearance of being strongly constricted at 

 its middle. I think it probable that some degree of constriction 



