THE SLOW-WOKM, ANGUIS FRAGILIS 29 



12 and 15 inches. In making such a measure- 

 ment the observer should carefully examine the 

 tail, to be certain it is all there. Very many speci- 

 mens have lost a portion of the tail, and this can be 

 recognised by the unusually blunt ending of the organ 

 in those cases. If the tail measures less than half 

 the total length, it has almost certainly been mutilated 

 at some time or other. In the females about half 

 the total length is tail, in males rather more than 

 half the total length, which reminds us that in snakes 

 also the tail is longer in males than in females. The 

 spot where the tail begins can be readily recognised 

 by noting the large anal scale, which is the most 

 posterior scale on the ventral aspect of the belly. 



There is no lateral fold in this lizard, nor any fold 

 in the neck region, and, as we have said, no indica- 

 tion at all of external limbs. The whole creature is 

 covered with very smooth shining scales, which are 

 rounded, not hexagonal. Those on the head are larger 

 than those elsewhere. In this species the teeth 

 " are curved backwards, fang-shaped, and have a faint 

 longitudinal groove on their anterior surface." ^ The 

 position of the ear is difficult to determine, as it has 

 the opening partially hidden from view by the scales 

 in that region. The eyes are small but very bright 

 and noticeable, in spite of the popular misnomer 

 of blind-worm. A marked characteristic is the great 

 smoothness of the skin ; in fact, it would be hard to 



^ Gadow, Amphibia and Reptiles, p. 539. 



