AIR-BREATHERS OF THE COAL PERIOD. 171 



Length of femur 0.7 inch. 



" tibia 0.45 " 



" principal bone of pelvis 0.7 " 



The other specimen above referred to, (Fig. 9.) 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. This specimen I have 

 very recently obtained, in breaking open a mass of matrix in which 

 I did not suspect its existence. It shows the humerus and radius 

 and ulna in a tolerable state of preservation, with a fragment 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. I believe that the maxillary repre- 

 sented in fig. 3, though now in a detached piece of stone, belonged 

 to this skeleton. 



While referring to these, my most perfect specimens, I think it 

 proper to quote my original description of the species, based on 

 the first of them, and published iu 1859 ; as the subject has since 

 been unfortunately obscured by inaccurate descriptions, consequent 

 on the mixture of sp< cimens and drawings, sent by me to London 

 for further examination. I quote from the journal of the Geolo- 

 gical Society, Vol. XVI. 



" Hylonomus, gen. nov." 



" The other reptilian remains represent three species belonging 

 to a generic form, which, so far as I am aware, has not been pre- 

 viously observed, and for which, in allusion to its forest habitat, I 

 propose the above name. As its typical species I shall describe 

 that which I would name Hylonomus Lyelli. Its cranial bones 

 are thin and smooth ; the condyle I have not been able to observe, 

 but there is a parietal foramen, and the parietal bones are arched 

 in such a manner as to indicate a rounded rather than flattened 

 skull, and a somewhat capacious brain-case. Its teeth are nume- 

 rous (about twenty-six in each maxillary bone), elongated, conical, 

 closely^set in a single series, in a furrow, protected externally by 

 an elevated alveolar ridge. In the intermaxillaries and extremities 

 of the mandibles the teeth are larger than elsewhere. Fig. 14, 

 (Fig. 5, Plate V. of this paper) represents a portion of the teeth of 

 the maxillary bone as exposed by the fracture of the outer ridge. 

 The vertebras are imperfectly preserved, but appear to have been 



