412 GALAPAGOS ARCJIirELAGO chap. 



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 afterwards, 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 outstretched legs. 



I opened the stomachs of .several, and found them largely 

 distended with minced seaweed (Ulvae), which grows in thin 

 foliaceous expansions of a bright green or a dull red colour. 

 I do not recollect having ob.served this seaweed 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 contained nothing 

 but the seaweed. Mr. Bynoe, however, found a piece of a crab 

 in one ; but this might have got in accidentally, 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, and 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 overhanging 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 a.s far as 

 I could, into a deep pool left by the retiring tide ; but it 

 invariably returned in a direct line to the spot where I stood. 

 It swam near the bottom, with a very graceful and rapid 

 movement, and occasionally aided itself over the uneven 

 ground with its feet. As soon as it arrived near the edge, but 

 .still being under water, it tried to conceal itself in the tufts of 

 seaweed, or it entered .some crevice. As soon as it thought 



