436 THE WONDERS OF GEOLOGY. Lect. IV. 



the skeleton of a reptile, in which are blended the osteologi- 

 cal characters of the crocodiles with those of the lizards. 



The vertebrae of the neck (PL IV. 2), several of the 

 back (3, 3), many ribs (4, 4), the two coracoid bones 

 (7, 7), and scapulae (8, 8), remain not far removed from 

 their natural order of juxtaposition. There are also several 

 dermal or skin bones, which supported the thick scales or 

 scutes ; of these the most extraordinary are certain large 

 angular bones (5, 5, 6, 6), which lie in the direction of the 

 vertebral column, and appear to have extended along the 

 back, like the horny serrated fringe in the Iguana. Many 

 other existing lizards have appendages of this kind, which 



Lign. 108.— Cyclura carinata. 

 (A recent Lizard, allied to the Iguana. Dr. Harlan.)* 



in some genera are largely developed ; as for example in the 

 Cyclura {Lign. 108). f 



There are several detached bones dispersed in the block 



* Medical and Physical Researches, by R. Harlan, M.D. F.G.S. 

 3vo. Philadelphia, 1835. 



f Professor Owen doubts the correctness of this interpretation, and 

 is disposed to regard these angular opines as abdominal ribs. He 

 particularly dwells on the unsymmetrical form of some of these bodies, 

 but which appears to me to have arisen from compression. The other 

 objections are not more valid ; and as it is now ascertained that the 

 internal structure of these spines is identical with that peculiar modi- 

 fication known only in the true dermal bones, the evidence is in favour 

 of this view of the subject. 



