STRANGE USE FOR A TAIL 



less allied species mentioned above, the male undertakes the 

 duties of incubation. 



Most Tortoises dig holes in the ground to receive their 

 eggs, which they afterwards cover up with earth. They 

 make these cavities in a very curious way, first drilling holes 

 with their tails and afterwards enlarging them with their 

 hind feet. This strange proceeding was observed very care- 

 fully by Brehm, who describes how, towards the close of a 

 warm day of early summer, after a long period of dry 

 weather, five European Pond-tortoises (Emys orbicularis) all 

 laid their eggs at the same time. They had chosen their 

 ground by seven o'clock in the evening not all in one place, 

 but a considerable distance apart. After deciding on a suit- 

 able spot where the earth was bare, each of them at once 

 began to bore a hole with its tail, stiffening it by contracting 

 the muscles strongly, and placing the tip firmly against the 

 ground. The middle part of the tail was then moved round 

 and round in a circle, until a cone-shaped hole was produced, 

 wide at the top but tapering to a point below, and almost 

 as deep as the length of the tail. When this curious 

 operation was completed, the animal immediately set to work 

 to enlarge the cavity with the help of its hind limbs. This 

 it did by scooping out, first with one hind foot and then with 

 the other, alternately, 'shovelfuls' of earth which were 

 heaped up like a rampart all the way round the sides of the 

 trench. The tortoise used its feet like hands, placing the 

 earth carefully in a circle at some little distance from the edge 

 of the pit, and the work was continued until the hole had 

 been dug as deep down as the hind limbs would reach. 



All this time the body had scarcely moved and the head 

 was kept inside the shell. The pit measured about five 

 inches across and was shaped more or less like an egg, being 

 widernnside than at the top. 



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