HABITS OF THE GREAT SOUTHERN TORTOISE. 37 



HABITS OF THE GREAT SOUTHERN TORTOISE. 



Bt n. s. shaler, 



PROFESSOR OF PALEONTOLOGY IN IIAEVAED UNIVERSITY. 



IN a recent paper publislied in " The Popular Science Monthly " 

 for February, 1888, I called attention to the effect on the soil 

 produced by various burrowing animals. At that time I had 

 not seen the work done in the under-earth by the Goplierus Caro- 

 linus, the largest of our North American tortoises, a creature 

 which, on account of its peculiar habits and the geological effects 

 which it brings about, is worthy of an attention which it has not 

 received. It is a well-known fact that land-tortoises are particu- 

 larly abundant on the American continent. Though found else- 

 where, and once extremely abundant in other lands, they are now 

 most plentiful and of largest size in the Americas, and the Gala- 

 pagos Islands, off the western coast of South America. The 

 greater part of these creatures have the habit of spending the 

 most of their lives on the surface of the ground, only resorting 

 to the under-earth for occasional shelter or during the annual 

 period of rest or hibernation. The gopher, on the other hand, has 

 developed the habit of underground life to such a degree that it 

 may fairly be reckoned as an essentially subterranean form. The 

 greater of our Southern species, and the one to which I shall devote 

 this paper, dwells for the greater part of its life below the surface, 

 only coming occasionally from its burrows. It appears to be by 

 far the largest species of our vertebrates which is normally sub- 

 terranean in its mode of life. The region at present occupied 

 by this species is narrowly limited ; it includes, so far as I 

 have been able to find, only the southernmost part of our Gulf 

 States, the southern portion of South Carolina, and the seaboard 

 region of Georgia, Alabama, and Florida. Within this consid- 

 erable area it is limited to the regions of the sand-plains, for 

 in those districts alone does it find the soil suited to its peculiar 

 habits. 



The gopher, it should be noted, is of considerable bulk, having 

 in adult specimens a length of fifteen inches or more, a width of 

 about twelve inches, and a thickness from the breast to back of 

 from eight to twelve inches. At first sight of the creature, it 

 seems as if its form was totally unfitted for underground move- 

 ments. Tha front of the animal is very blunt, and calculated to 

 oppose about the maximum of resistance to movements through 

 the earth. The fore-limbs are not to any degree specialized for 

 grappling with the earth which has to be moved to form the 

 burrow, and the head does not differ from that of our ordinary 



