BEHAVIOR OF THE LOGGERHEAD TURTLE IN DEPOSITING ITS EGGS. 



By S. O. Mast. 



The loggerhead turtle ordinarily comes out of the sea in the early 

 part of the night and lays its eggs in the sand on the beach above high- 

 tide water-mark. On July 11,1910,! was fortunate enough to be present 

 when a turtle came out to lay on Loggerhead Key, Florida, while it was 

 still daylight (7^5™ p. m.). This individual was about 3 feet long and 

 2 feet wide. She came out at right angles to the water line and proceeded 

 directly up the beach 50 to 60 feet, where she immediately began to make 

 her nest. There was no indication whatever of a process of selection of 

 the place for the nest, as some have asserted in describing the breeding 

 habits of this turtle. When the turtle reached the nesting-place she 

 stopped and began at once to move the posterior end from side to side, 

 throwing the sand out sidewise and forward alternately, with the two 

 hind flippers, to a distance of 5 to 6 feet. Thus a crescent-shaped trench 

 was made, wide and deep in the middle and narrow and shallow at either 

 end. This trench was over 4 feet long and nearly 10 inches deep in the 

 middle. The lateral movement of the turtle during this process of dig- 

 ging was largely due to the action of the muscles connected with the 

 front flippers, which remained stationary as the body turned on them. 



After the trench was finished the turtle took a position so that the 

 right hind leg was very nearly over the middle of the bottom of it. This 

 flipper was then thrust vertically down into the sand (the fiat surface 

 being nearly parallel with the long axis of the body) and the end turned 

 in under the sand so as to form a cup much like one formed by a human 

 hand partly closed. The posterior end of the animal was then raised by 

 the action of the left leg and pushed to the right. During this process 

 the right flipper, containing a fair-sized handful of sand, was of course 

 raised and as the posterior end of the body moved to the right the flipper 

 gradually rotated so as to face backward; it was then thrust out to the 

 side and inverted so as to empty the sand in a heap, just in front of which 

 the foot was placed on the ground in the customary position. The left 

 flipper was now directly over the hole made by the right one and used 

 in removing sand just as described, except that it took the sand from 

 the right side of the hole while the right flipper took it from the left 

 side. Before the body was pushed back to the left by the right leg it 

 made a sudden movement forward and threw out a considerable bit of 

 sand, making a hole just in front of the place where the sand taken from 

 the nest had been deposited. This sand was pushed into the hole in 

 front of it when the turtle moved back to the right again and thrown 

 out just before it moved to the left the following time. Thus the two 

 5 65 



