OF TILGATE FOREST. 
325 
of tlie length of the entire animal ; in the Monitor 
nearly the same ; and in the Iguana one-ninth. If, 
therefore, the original animal bore the linear pro- 
portions of the first and second, it would not exceed 
20 feet in length, and if of the Iguana not 30 ; and 
although, from the mixed characters of the skeleton, 
and the size and strength of the omo])lates and co- 
racoids, it seems probable that it was larger than 
the ordinary Crocodiles, yet its total lengtli cannot 
reasonably be estimated at more than 25 feet ; and 
from the annular sutures in the vertebnn being 
almost obliterated, there is reason to conclude tliat 
the individual was an adult. This creature, tlien, 
did not approach in magnitude to the Iguanodon, 
or Megalosaurus, by more than one-half ; and yet 
the })i’ocesses, if assumed to be vertebral, indicate 
vertebrae much larger than any that have been dis- 
covered of those animals. Another conjecture has 
occurred to me, and, extravagant as it may appear, 
it seems the most probable. It is known that many 
of the lizards, particularly the Iguanas, have large 
cartilaginous processes with horny coverings, which 
form a sort of dermal fringe along the back : in an 
animal 5 feet long, these spines are about an incli 
in height. (A sketch of the recent Iguana cornuta 
is here introduced, for illustration.) Now the 
y 3 
