185 
fromrthe sandstone of Tilgate forest y Sussex. 
osteology of the latter is at present so limited, that until some 
connected portion of the skeleton shall be discovered, it is 
impossible to distinguish the bones of the one from those of 
the other. Since, however, the teeth of the iguanodon are not 
known to occur in the Stonesfield slate, perhaps such of the 
bones from Tilgate forest as resemble those figured and 
described by Professor Buckland, in Vol. I. Second Series of 
the Geological Transactions, may be attributed to the mega- 
losaurus ; while others not less gigantic may be assigned to 
the iguanodon. That the latter equalled, if not exceeded the 
former in magnitude, seems highly probable ; for if the re- 
cent and fossil animal bore the same relative proportions, the 
tooth, fig. 1. must have belonged an individual upwards of 
sixty feet long ; a conclusion in perfect accordance with that 
deduced by Professor Buckland from a femur,* and other 
bones in my possession. 
The vertebrae, as in the greater part of the fossil saurians, 
differ very materially from those of the recent iguana, cro- 
codile, &c. They are not concave anteriorly, and convex 
posteriorly, but have both faces slightly depressed, resem- 
bling in this respect the vertical column of one of the fossil 
crocodiles of Havre and Honfleur. But among the recent 
lacertas there are some, as the Proteus of Germany, the 
Syren of Carolina, and the Axolotl of Mexico, in which the 
vertebrtC are deeply cupped at both extremities ; and since 
the fossils in question are clearly of the saurian type, hav- 
ing the annular part united to the body of the vertebra by 
• Vide Professor Buckland’s notice on the Megalosaunis. 
Second Series, p. 391. 
2 B 
Geol. Trans. Vol. I. 
MDCCCXXV. 
