THE VOYAGE OF THE BEAGLE 409 



"They go to sea in herds a-fishing, and sun themselves on 

 the rocks; and may be called alligators in miniature." It 

 must not, however, be supposed that they live on fish. When 

 in the water this lizard swims with perfect ease and quick- 

 ness, by a serpentine movement of its body and flattened tail 

 — the legs being motionless and closely collapsed on its sides. 

 A seaman on board sank one, with a heavy weight attached 

 to it, thinking thus to kill it directly; but when, an hour after- 

 wards, he drew up the line, it was quite active. Their limbs 

 and strong claws are admirably adapted for crawling over the 

 rugged and fissured masses of lava, which everywhere form 

 the coast. In such situations, a group of six or seven of 

 these hideous reptiles may oftentimes be seen on the black 

 rocks, a few feet above the surf, basking in the sun with out- 

 stretched legs. 



I opened the stomachs of several, and found them largely 

 distended with minced sea- weed (Ulvae), which grows in 

 thin foliaceous expansions of a bright green or a dull red 

 colour. I do not recollect having observed this sea-weed in 

 any quantity on the tidal rocks ; and I have reason to believe 

 it grows at the bottom of the sea, at some little distance from 

 the coast. If such be the case, the object of these animals 

 occasionally going out to sea is explained. The stomach con- 

 tained nothing but the sea-weed. Mr. Baynoe, however, found 

 a piece of crab in one; but this might have got in acci- 

 dentally, in the same manner as I have seen a caterpillar, in 

 the midst of some lichen, in the paunch of a tortoise. The 

 intestines were large, as in other herbivorous animals. The 

 nature of this lizard's food, as well as the structure of its 

 tail and feet, a:.l the fact of its having been seen voluntarily 

 swimming out at sea, absolutely prove its aquatic habits; 

 yet there is in this respect one strange anomaly, namely, that 

 when frightened it will not enter the water. Hence it is 

 easy to drive these lizards down to any little point overhang- 

 ing the sea, where they will sooner allow a person to catch 

 hold of their tails than jump into the water. They do not 

 seem to have any notion of biting; but when much frightened 

 they squirt a drop of fluid from each nostril. I threw one 

 several times as far as I could, into a deep pool left by the 

 retiring tide; but it invariably returned in a direct line to 



