| 
. 
: 
: 
101 
The gular pouch which hangs like the dewlap of a bull beneath 
its throat can be inflated*, but it is not exactly known under 
what circumstances, ordinarily, it has recourse to this power of in- 
flation. When filled with air it would give breadth and buoyancy 
to the body, and if its habits are as aquatic as some accounts make 
them [those of Iguana proper] to be, it would afford to an her- 
bivorous animal no unimportant aid while swimming and cropping 
‘its flowery food.’ When excited it assumes a menacing attitude, 
and directs its eye to the object of attack with a peculiarly sinister 
look. At this time it inflates the throat, erects the crest and dente- 
lations on the back, and opens the mouth, showing the line of those 
peculiarly-set white teeth, with serrated edges, so excellently made 
to illustrate the remains of the gigantic fossil Iguanodon. The prin- 
ciple of their construction is so precisely similar, as to leave no doubt 
of the genuine connexion of the extinct with the existing herbivorous 
lizard. The adaptation of both is for the cropping and cutting of 
vegetable food. 
“In defending itself from attack, the Iguana converts its long 
flexible tail into no unimportant weapon. The dentelated upper 
edge, drawn rapidly over the body and limbs of an enemy, cuts like 
asaw. The twisted attitude which it assumes when approached is 
converted into a quick turn, in which movement the tail is nimbly 
struck by an overblow from one side to another, and then jerked 
round. I have observed the same application of the tail to purposes 
of defence in the crocodile, and there can be little doubt that the 
dentelated crest upon this part of the body of lizards is for the in- 
fliction of serrated wounds. The lacerations which dogs suffer in 
attacking the Iguana are remarkably severe. 
«« There can be no doubt that the Iguana voluntarily takes to the 
water ; but whether it delights to refresh itself in that element, as we 
should be led to suppose by the observation that it sports in it, I 
cannot learn from any of our people here. The one kept in the 
Zoological Gardens in the Regent’s Park was seen to enter and cross 
a small pond, the fore-feet being motionless during the animal’s pro- 
gress through the water. It is curious, however, that whilst the dry, 
sterile hills near us abound with Iguanas, the banks of the Rio Cobre, 
a river so near its haunts, are scarcely ever visited by them.” 
After my arrival in England, the above notes coming under review, 
in my study of the Saurians I had brought home, I was induced to 
make further inquiry of Mr. Hill, whether in describing the inflation 
of the pouch, and the defensive action of the tail, he spoke from his 
own observation. From his reply I extract the following remarks :— 
Biastee ta The purposes of defence, to which I represented it as 
applying its long tail with its armature of pointed and triple-edged 
scuta, were suggested to me by the negroes, who were present when 
I was examining the specimen I mentioned as forty-five inches in 
* I believe my friend has fallen into a common error here. If I may judge 
from analogy in the genera Anolis and Dactyloa, the gular pouch in the /guanide 
is extensible but not inflatable, as I hope to show in a future paper on the habits 
of these genera.—P.H.G. 
