Il6 REPTILES AND BIRDS. 



has no enemy whatever on shore, whereas at sea it must often fall 

 a prey to the numerous sharks. Hence, probably urged by a fixed 

 and hereditary instinct that the shore is its place of safety, whatever 

 the emergency may be, it there takes refuge. I asked several of 

 the inhabitants if they knew where it laid its eggs : they said, that 

 although well acquainted with the eggs of the other kind, they had 

 not the least knowledge of the manner in which this species is 

 propagated — a fact, considering how common an animal this lizard 

 is, not a little extraordinary. During our visit (in October) I saw 

 extremely few small individuals of this species, and none, I should 

 think, under a year old. From this circumstance it seems probable 

 that the breeding season had not commenced/' 



The terrene species (Amblycephalus subcristatus), unlike the aquatic 

 one, is confined to the central islands of the Gallapagos archipelago, 

 where they inhabit both the higher and damp, as well as the lower 

 and sterile parts ; but in the latter they are much more numerous. 

 " I cannot give a more forcible proof of their numbers," relates Mr. 

 Darwin, " than by stating that, when we were left at James Island, 

 we could not for some time find a spot free from their burrows on 

 which to pitch our tent. These Lizards, like their brothers of the 

 sea-kind, are ugly animals ; and, from their low facial angle, have a 

 singularly stupid appearance. In size perhaps they are a little 

 inferior to the latter, but several of them weighed between ten and 

 fifteen pounds each. The colour of their belly, front legs, and head 

 (excepting the crown, which is nearly white) is a dirty yellowish 

 orange ; the back is of a brownish red, which, in the younger 

 specimens, is darker. In their movements they are lazy and half- 

 torpid. When not frightened, they slowly crawl along, with their 

 tails and bellies dragging on the ground. They often stop and 

 doze for a moment, with closed eyes, and hind legs spread out on 

 the parched soil. These lizards inhabit burrows ; which they 

 sometimes excavate between fragments of lava, but more generally 

 on level patches of soft volcanic sandstone. The holes do not 

 appear to be very deep, and they enter the ground at a small angle ; 

 so that when walking over one of these lizard zvarrens, the soil is 

 constantly giving way, much to the annoyance of the tired pedestrian. 

 This animal, when excavating its burrows, alternately works the 

 opposite sides of its body. One front leg for a short time scratches 

 up the soil, and throws it towards the hind foot, which is well 

 placed so as to heave it beyond the mouth of the hole. This side 

 of the body being tired, the other takes up the task, and so 

 alternately. I watched one for a long time/' continues Mr. 



