GECKOS, LIZARDS, AND CHAMELEONS. 97 



reptile 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." Darwin describes the lizard as a 

 "hideous looking creature, of a dirty black 

 colour, stupid and sluggish in its movements. 

 The usual length of a full-grown one is about a 

 yard, but there are some even four feet long ; a 

 large one weighed about twenty pounds : on the 

 island of Albemarle they seem to grow to a greater 

 size than elsewhere." 



The American Basilisk (Basiliscus americanus) 

 is another expert swimmer. It is an arboreal 

 lizard, preferring the branches of trees which 

 overhang the water, into which it plunges at the 

 slightest alarm. It swims by rapid strokes of the 

 fore-limbs, the long tail trailing behind. Both in 

 its method of swimming and in its habit of seek- 

 ing safety by taking refuge in the water, this 

 species stands in strange contrast with the 

 Galapagos Sea Lizard just described. 



Many species of the large family of Iguanas 

 are more or less aquatic. The Water Monitor 

 (Faranus salvator), which ranges from India, 

 through the Malayan region of China and Aus 

 tralia, and attains a length of seven feet, is a strong 

 swimmer, occasionally entering salt water. The 

 Water Monitor, and probably other species of 

 the same genus, possesses one peculiarly interest- 

 ing adaptation to aquatic habits, in the shape of 

 a pair of large cavities within the snout leading 

 from the nostrils. When the latter are closed 

 G 



