TIIE GEOLOGIST. 



" Ayes, or Birds. — Palceomis Struthionoides, n. g. (E.). It is a re- 

 markable fact that the remains of birds are so rare in the sandstones 

 and shales in which their footprints are so common. The only frag- 

 ment of a bone which has been obtained in the country, which could 

 be referred to this class of warm-blooded animals, I procured from 

 the red and variegated sandstones of Anson County, N. C. It is a 

 portion of the sacrum (fig. 114), natural size, and contains six verte- 

 bras anchylosed together. The figure shows the under side, and 

 brings to view their perfect confluence. Upon the sides these bodies 

 are seen projecting laterally from the mass of bone. It is three and 

 one-half inches long, ODe and six-tenth inches wide, and one and two- 

 tenth inches thick. (See PI. IV.) 



" A microscopic examination of the bone-cells (fig. 115) confirm s 

 the opinion expressed relative to the class of animals to which it be- 

 longs. 1, shows the bone-cells of a fish ; 2, those of a reptile ; and 

 the remaining five the cells of the bone under consideration. The 

 size of this bone proves that it belonged to a large heavy bird. The 

 width of the same bone in the eagle is half an inch. It is more than 

 three times the size of the largest of the kind, but it is not the 

 proper bird with which to compare it, for it is highly probable that 

 it more resembled the StrutMones, or ostriches,- — birds with thick 

 toes, — than any other living family. Its specific name has an allu- 

 sion to this resemblance. The footprints of birds are mostly made by 

 those which possessed toes of this description, especially those which 

 are confined to the sandstone of the valley of the Connecticut." 



The first notice of bird remains in the Oolite of England was given 

 in the ' Quarterly Journal of the Microscopical Society of London,' 

 1857, vol. v. p. 63, in an article, illustrated with plates, " On the 

 Existence of Birds during the deposition of the Stonesfield Slate, 

 proved by a comparison of the Microscopic Structure of certain 

 Boxes of that Formation with those of Becext Boxes. By the 

 Eev. J. B. P. Dennis, E.G.S., of Bury St. Edmund's." 



Erom extensive observations made upon the bones of birds, Mr. 

 Dennis found that in their microscopic characters, these bones are as 

 distinct from those of mammifers as the latter are from the bones 

 of saurian s. " As the lacuna in the saurian bone exceeds that of the 

 mammal in the size of its canaliculi, so does the latter exceed that 

 of the bird ; and as they are more numerous and more branched in 

 the bird than in the mammal, so, in like manner, are they more so 

 in mammalian than in saurian bone." " It is in birds," he continues, 

 " that the Haversian tubes attain their most elegant and varied reti- 

 culations, not fortuitously, but with design, and that intimately con- 

 nected with the life and habits of the animal. In fact, each bone 

 is a study in itself, and involves a knowledge of the muscles that move 

 it, as well as of the use it is designed for." 



The object of his paper, Mr. Dennis says, " is to prove, from a 

 general exposition of the structure of birds, that they had representa- 

 tives on this planet when the Stonesfield Slate was still the soft mud 

 of a large estuary ;" and fortius purpose he enters (for the thorough 



