THE SAURIAN S. ! 83 



present, even should there be no limbs, as in Anguis fragilis ; and 

 there is generally a vestige of a pelvfs, but more thoroughly 

 developed where there. are legs to suppdrt. Most lizards are 

 exceedingly active, darting about with a swiftness that almost 

 baffles the eye, while to detect motion in the legs is .impossible. 

 Even those thiek-set species, which ' in' confinement appear so 

 sluggish, scarcely moving from day to day, are, in their native 

 tropics, almost as nimble as the slender ones. The skeleton of 

 a lizard (fig. 28), with its long and flexible spine, movable ribs, and 

 slender limbs, all indicate activity and nimbleness. , 



Lizards are said to be able to reproduce their limbs if lost or 

 maimed. So far as my own observation goes, I doubt if the 

 bony structure is ever perfectly renewed, but only an imperfect 

 cartilaginous claw or taiLtip. It is possible that by very slow 

 degrees the cartilage may become ossified ; but the same reptile 

 should be kept alive and well, and be carefully watched for a. 

 long period, before the fact can be established. So here is an 

 opportunity for our young collector to make and record obser- 

 vations that may be of real scientific value ; viz., to see how long 

 he can preserve the life of his pets, and to note down accurately 

 how long the lizards take to repair their limbs or their tail, when 

 one is nipped off by accident, or by a fellow-captive. A viviparous 

 lizard, brought to me from Hampstead Heath in May 1885, had 

 an uneven, as if injured, tail, which soon seemed about to break in 

 several places. In just one month it was nearly severed within 

 an inch of the body, and next day was off. Five weeks afterwards 

 sloughing took place, and then, within the contracted scales of 

 the stump, appeared the first indication of a new tail. In three 

 more weeks (August 16th) the new point was a quarter of an inch 

 long, looking exactly like the lead of a freshly cut pencil showing 

 beyond the cedar, but quite smooth, soft, and pliant, and with no 

 appearance of scales. The autumn being sunless and chilly the 

 lizard ceased to feed, and, being feeble from the first, dwindled 

 and died before the winter set in, and before the tail had made 

 much progress. During four months it had attained only half 

 an inch in length, having no indication of scales, and being 

 still lead-coloured and smooth. In another lizard, a healthy 

 Agilis, a portion of whose tail was nipped off by a com- 

 panion in mistake for a worm, the renewal was much more rapid. 

 In about the same time the new point was one inch long, and 

 was beginning to show indications of a scaly surface. Several 

 more months elapsed before the perfect scales appeared, though 

 the point had ceased to grow, and was still soft and pliant. There- 

 fore, should the bony skeleton be restored, it would be only after 



