young specimens as a light spot in the skin of the 

 forehead; this is usually overlaid by pigment in the 

 adult, but can sometimes be seen even in old spec- 

 imens. 



The Tuatera lives in burrows, often in com- 

 pany with the Puffin {F rater cula) , It is held in 

 superstitious awe by the natives but is nevertheless 

 killed by them for food. 



The skeleton on exhibition is that of a young 

 adult. 



SQUAMATA (Order). 



The order Squamata contains most of the 

 existing species of Reptiles. It is divided into two 

 suborders, the SAURIA (Lizards) and the SER- 

 PENTES (Snakes). Lizards and snakes are most 

 abundant and reach their greatest size in the trop- 

 ical regions of the earth, but are very widely dis- 

 tributed; the snakes are absent from many islands. 

 Most lizards are terrestrial, but some are arboreal 

 or semi-aquatic, and there is a single marine form. 

 The only lizards which have been proved poison- 

 ous are the two species of the mono-generic fami- 

 ly Helodermatidae of the Southeastern U. S. 

 and Mexico (Heloderma hcrridum and H. sus- 

 pectum). Lizards generaJly possess limbs, but 

 there are numerous gradations in the number and 

 size of digits and some forms are limbless (AnguiSf 

 Ophisaurus) and some even worm-like {Rhineura 

 of Florida). 



The snakes, while seemingly degenerate forms, 

 are actually much more specialized than the 



