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THE CARBONIFEROUS SYSTEM. 



paper already referred to. The bones being small and of dark colour, 

 are not very conspicuous, and many of them are broken, but many 

 are beautifully perfect ; and even those which are removed have left 

 very distinct moulds of their form in the fine-grained matrix. In the 

 figure I have carefully traced their outlines in their natural position, 

 with the exception of the maxillary bone and mandible, which are 

 removed from their place in the matrix, to bring the whole into a 

 more compact form. The specimen also shows, in addition to the 

 bones delineated, many fragments of the skull and scapular bones, 

 crushed in such a manner that their forms cannot be distinguished. 

 The specimen shows remains of thirty vertebras, of which four appear 

 to belong to the neck, and the rest are probably nearly all dorsal and 

 lumbar. Of about twenty ribs more or less complete fragments 

 remain. The fore limb is represented only by the impression of a 

 humerus, but other bones which may have belonged to it are scattered 

 elsewhere on the stone. The pelvis is nearly entire, though crushed 

 and- flattened. One thigh bone remains tolerably perfect, and beside 

 it lie the tibia and a part of the fibula, with several bones of the foot. 

 The dimensions of these parts are as follow : — 



The other specimen above referred to shows the bones of the trunk, 

 and part of those of the hind and fore limb, of a small individual, 

 nearly in their natural position, and is remarkably instructive, as giving 

 some idea of the general form of the trunk. It shows the humerus 

 and radius and ulna in a tolerable state of preservation, with a frag- 

 ment of the scapula. About thirteen dorsal and lumbar vertebras can 

 be made out, nearly in their natural position ; and there are remains 

 of five of the ribs. The hind limb is represented by fragments of the 

 femur, tibia, and fibula. 



It is evident, from the remains thus described, that we have in 

 Hylonomus Lyelli an animal of lacertian form, with large and stout 

 hind limbs, and somewhat smaller fore limbs, capable of walking and 

 running on land ; and though its vertebras were imperfectly ossified 

 externally, yet the outer walls were sufficiently strong, and their 

 articulation sufficiently firm, to have enabled the creature to erect 



