56 REPTILES 



in length ; while when a year old their length was eighteen 

 inches, showing an increase of ten inches in a twelvemonth. 

 A year later (in August) their average length was twenty-three 

 inches ; but in the following March their average length was 

 three feet nine inches. At the time when these last measure- 

 ments were taken the alligators were only two and a half years 

 old, during which time they had increased thirty-seven inches 

 in length. Probably the rate of growth would not continue at 

 this rapid pace, but even so an alligator of twelve feet in length 

 need not be more than a dozen years old. 



It might be urged that the growth of specimens in captiv- 

 ity is abnormally rapid ; but even if this were so, the rate in a 

 wild state would be in excess of that given in the passage 

 quoted above. The observer who recorded the dimensions of 

 the New York specimens is, however, of opinion that the 

 growth in the wild state is at least as rapid as in the case of 

 captive specimens x : — 



" From observations made in the South Carolina bayous by 

 the writer, it would seem that the growth of wild alligators 

 must be fully as rapid if not more so, than that of the 

 specimens reared in captivity. The females construct their 

 nests near shallows teeming with fish, and in an atmosphere of 

 heat and humidity. The young reptiles probably grow more 

 rapidly when wild than when confined. Of course hibernation 

 must be considered in the case of the wild reptile. During 

 this period growth must be very slow, or cease altogether. 

 Yet the writer has always noted that reptiles in captivity, no 

 matter how elaborate may be the facilities for their care, or the 

 voracity evinced by the reptiles themselves, never grow so 

 rapidly as those in a wild state. Repeatedly has this been 

 observed by comparing the young of wild and captive-bred 

 snakes, the ages of which are easily distinguished." 



As to the duration of life in reptiles, information is imper- 

 fect, although the most satisfactory dates are afforded among 

 tortoises, some of which attain an age which may be counted 

 by centuries instead of years. As we have seen, the painted 

 terrapin is known to live more than five-and-twenty years. 

 Again Gilbert White's tortoise " Timothy," which belonged to 

 the species Testudo ibera and whose shell is exhibited in the 

 1 Seventh Annual Report, New York Zoological Society, p. 150. 



