44 BRITISH LIZAEDS 



have demonstrated to be nothing more nor less than a 

 degenerate eye. It is deeply embedded in the slow- 

 worm, and is not at all affected by light ; but in the 

 remarkable New Zealand lizard, Sphenodon, this median 

 eye is in a more perfect state of development. A 

 detailed study of this pineal body would be beyond 

 the province of this work, but its existence is a point 

 of too great interest to be omitted altogether. Much 

 has been written about it in zoological literature, 

 which those who are specially interested can consult. 



