FAUNA OF CAPE EEGION 207 



The point, however, I wish to direct special attention to 

 is the fauna as a whole inhabiting the southern part of the 

 long peninsula of Lower California. This peninsula, for which 

 many people retain the Spanish name " Baja California," is 

 a narrow strip of broken mountainous land, nearly eight hun- 

 dred miles long, and averaging about fifty miles in width. On 

 the western side of this region there are a series of isolated 

 peaks or ridges rising to a height of about 2,000 feet. An 

 older range of mountains, composed of granite and gneiss, lies 

 along the eastern flank of the peninsula. Most of this vast 

 country is bare and desert-like, with a scanty flora, water 

 being difficult to obtain.* As soon as we enter what is called 

 the " Cape Eegion " all this is changed. Eunning water can 

 be procured throughout the whole year, in the larger canons 

 at any rate, and this gives rise to an extremely rich and 

 exuberant vegetation. While almost the whole of the fauna 

 and flora of the peninsula are merely a continuation of those 

 of Calif omia and Arizona, having evidently passed into it from 

 the north and east, the southernmost tip, or Cape Eegion, has 

 an entirely different set of ajiimals aaid'plants. I have already 

 alluded to the occurrence here of Euchirotes biporus, a very 

 peculiar burrowing lizard belonging to the ancient family of 

 Amphisbaenidae, and of the boa Lichanura trivirgata. Another 

 reptile, which is quite peculiar to the same district, is Cteno- 

 saura hemilopha. This great lizard, of nearly two feet in 

 length, possessing a high crest along its back, a green head 

 and pale yellow body spotted with olive, brown and black, is a 

 most remarkable and striking object. The only near relations 

 of the burrowing lizard, and of the great active Ctenosaura, 

 live in south-western Mexico. But the Mexican forms do not 

 belong to the same species. We cannot, therefore, assumie that 

 these lizards have been accidentally carried across the Gulf 

 of California, which has a width of about one hundred miles 

 near the tip of the peninsula. The genus Ctenosaura, it 

 may be mentioned, is related to Cyolura of the West Indies, 

 and Brachylophus of the Fiji and Friendly Islands, these 

 genera all belonging to the great family Iguanidae, which 

 has inhabited America since Cretaceous times (p. 202) .f 



* Merrill, G. P., "Lower California." 



t Denburgh, J. van, " Herpetology of Lower California," p. 78. 



