CULTIVATION OF MARINE ANIMALS IN JAPAN 690 



having the least specific gravity, always occupies the highest spot 

 of the yolk in whatever position the egg may happen to be dropped. 

 The eggs are generally spherical in shape, although sometimes more 

 or less oblate. Their diameter is in the neighborhood of twenty 

 millimeters, the largest being as large as twenty-four millimeters, 



FIG. 2. Section and plan of a turtle-pond 



the others smaller according to the size of the females. The number 

 of eggs in one deposit varies from seventeen or eighteen up to twenty- 

 eight or more, the smaller individuals producing the smaller number. 



When the eggs have all been deposited, the turtle's legs are 

 again put in requisition, this time to fill up the hole, which is done 

 by alternate motions as before. The earth about the hole is used at 

 first, but search is made for more loose earth for a little distance, as 

 far around as the legs can reach with a slight motion of the body 

 either to the right or left without moving the front legs. Toward 

 the end of the process the loose earth is trampled down. When the 

 hole is well filled up to the level of the ground, the turtle turns 

 around and goes immediately down into the water, not casting even 

 one backward glance. 



I have noticed an interesting contrast between the behavior of 

 Trionyx and of Clemmys during the egg-deposition. If one wants 

 to watch a Trionyx depositing eggs, one has to crawl on all fours 

 behind the plank wall of the pond and peep through a hole, being 

 careful not to show one's self. The moment the snapping-turtle sees 

 any one, it stops in whatever part of the egg-laying process it may be 

 engaged and plunges straight into the water. Utterly different is the 



