IGUANAS. 125 



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, con- 

 sidering how common an animal this Lizard is, not a little extra- 

 ordinary. 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 j^ounger specimens, is darker. In their move- 

 ments they are lazy and half-torpid. When not frightened, they 

 slowlv 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 frag- 

 ments 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 wallcing over one 

 of these Lizard ivarrens, 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 times 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 tidies up the task, and so alternately. I watched 



