THE PARIETAL EYE 



iguana deposits its eggs in the sand of the seashore in 

 such localities as enable it to reach the sea. Oddly 

 enough it is said that though the iguana can swim with 

 ease, it objects to sea water, which, in view of the locality 

 chosen by it for egg laying, is curious. An ally of the 

 iguana, the marine lizard, Oreocephahis of the Galapagos, 

 does not share this distaste for sea water ; it is an inter- 

 esting fact that even iguanas can be submerged for a 

 long time in water without being drowned ; and it will be 

 remembered that Darwin tried, and in vain, to drown 

 an Oreocephalus. The dewlap under its chin is not an 

 inflatable structure, as some have thought or at least 

 asserted ; but a very near ally of Iguana, known as 

 Metopoceros cornutus, has a really dilatable throat pouch 

 with which to express anger and perhaps also convey 

 terror. This last iguana is black where our iguana is 

 green ; and yet it is also arboreal. 



AN ANCIENT LIZARD 



For hours together this reptile will sit like Saturn, 

 " quiet as a stone," with hardly a blink of eyelid to indi- 

 cate that it is not intended, like the chamois of Mark 

 Twain, to fulfil obligations towards the visitor. The 

 quiet atttude is not, however, an attribute of Sphenodon 

 (or Hatteria) punctata only. It is common to the reptile 

 tribe who live often two lives in sharp contrast. At 

 times the eye can hardly follow the brisk movements of 

 a small lizard ; at other times it is as if carved or stuffed. 

 The tuatera presents no features which mark it out to 

 the uninstructed eye as anything unlike the average of 

 lizards. And, indeed, if all we had to judge by were 

 external form and habits, Hatteria would be most un- 

 questionably relegated without doubt to the Lacertilia. 

 It has blackish olive hues, which are not unknown in the 

 lizard tribe. The close-set crest along the back is to be 

 seen in the iguana ; even the " parietal eye," so con- 



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