OF NATURAL HISTORY. 51. o 



FiJheSy whofe bones are more cartilaginous than thofe of 

 men and quadrupeds, are long of acquiring their utmoft 

 growth, and many of them live to great ages. Gefner gives 

 an inftance of a carp in Germany which he knew to be one 

 hundred years old*. BufFon informs us, that, in the Count 

 Maurepa's ponds, he had feen carps of one hundred and fifty 

 years of age, and that the faft was attefted in the moft fatis- 

 facStory manner. He even mentions one which he fuppofed 

 to be two hundred years oldf . Two methods have been de- 

 Yifed for afcertaining the age of fiflies, namely, by the cir- 

 clesof thercales,and by a tranfverfe fe£lionof the back-bone. 

 When a fc le of a fifh is examined by the microfcope, it is 

 found to conlift of a number of circles within one another, 

 refembling, in fome meafure, thofe rings that appear on the 

 tranfverfe fedtions of trees, by which their ages are computed. 

 In the fame manner, the ages of fifhes may be afcertained 

 by the number of circles on their fcales, reckoning for each 

 ring one year of the animal's exiftence. The ages of Buffon's 

 carps were chiefly determined by the circles on their fcales. 

 The age of fifties that want fcales, as the fkate and ray-kind, 

 may be pretty exa<Stly known by feparating the joints of the 

 back-bone, and obferving minutely the number of rings 

 which the furface exhibits. Both of thefe methods may be 

 liable to deception ; but they are the only natural ones which 

 have hitherto been difcovered. The longevity of fifties has 

 been afcribed to feveral caufes. The element in which they 

 live is more uniform, and lefs fubjedt to accidental changes 

 than the air of our atmofphere. Their bones, which are 

 more of a cartilaginous nature than thofe of land animals, 

 admit of indefinite extenfion ; of courfe, their bodies, inftead 

 of fiifFering the rigidity of age at an early period, which is 

 the natural caufe of death, continue to grow much longer 

 than thofe of moft land-animals. 



Gefner de Pifc. page 31^ 

 t Epocjues de la Nature, page 18s. 



