Newman, Habits of Tortoises. 141 



The nests are of somewhat smaller dimensions and the flask- 

 shaped expansion is more symmetrically placed, scarcely more 

 bulged on one side than on the other. Two layers of eggs are 

 deposited in the flasklike expansion but the last two or three eggs 

 are placed in the narrow neck, the uppermost egg being some- 

 times only about two inches from the surface. 



It is difficult to frighten them away after they have once decided 

 upon a nesting place. When surprised they stop work but soon 

 resume it and continue it to the end, even while the observer is 

 in plain view. The nest of Graptemys is a finished product, 

 all traces of nest-making being obliterated. This is accom- 

 plished by dragging the smooth plastron back and forth across 

 the small area that had been disturbed by nesting. . 



The eggs are ellipsoidal in shape, of a dull white color, and have 

 a rather soft, easily indented shell. The number laid by one 

 female at one time varies from eleven to fourteen. 



The eggs hatch, as a rule, late in August or early in September, 

 the young burrowing to the surface through the sand. When 

 they emerge they are covered with sand that adheres for some 

 time. Their instinct directs them unerringly toward the water 

 and they frequently have to travel almost incredible distances 

 before reaching the lake or a tributary stream. On two occasions 

 I have found recently hatched Graptemys, at a distance of 

 about a quarter of a mile from the water, traveling steadily and 

 in an approximately correct direction toward the lake. At the 

 observed rate of progress they would reach the lake in about 

 two days. 



For some time I was greatly puzzled by the frequent discovery 

 of newly-hatched Graptemys during the months of May and 

 June. Farmers in the vicinity frequently plowed up nests of eggs 

 that were nearly ready to hatch. 



These facts have been explained by the observation of occasional 

 specimens nesting during the latter part of July. Eggs laid at 

 that time would have only about five or six weeks of steadily warm 

 weather in which to develop, and would be retarded by the chilling 

 of the ground in October. Thus the well advanced embryos 

 must pass the winter in a condition of dormancy analogous to 

 that observed in hibernating adults. 



On no occasion have I caught a female nesting whose carapace 

 length was less than nineteen centimeters and whose age was less 



