702 OCEANOGRAPHY 



the pond, leaving perhaps one foot margin between them and the 

 water. Two successive planks are not placed contiguous, but a space 

 of about three feet is left between every two, and closed by a bam- 

 boo screen put up in the shape of an arc of a circle, with its con- 

 vexity toward the pond. Thus the slope or the bank where the 

 eggs have been deposited is completely cut off from the pond itself. 

 In the centre of every pocket-like arched space made by a bamboo 

 screen an earthenware jar is placed, with its top on the level of 

 the ground, and some water is put into it. This elaborate arrange- 

 ment is for the reception of the young tortoises, which, as soon as 

 they break through the egg-shells, --those belonging to the same 

 deposit generally coming out at the same time, crawl up to the 

 surface of the ground by a hole or holes made by themselves, and go 

 straight down the incline toward the pond, as naturally as the 

 duckling takes to the water. They are stopped, however, in their 

 downward hydrotaxic course by the planks put up, as stated before, 

 around the pond, and they crawl along the length of the planks, 

 and sooner or later drop into the jars placed in the recesses be- 

 tween every two planks. A man going around once or twice a day 

 can easily collect from these jars all the young hatched since the 

 last visit. 



The young just hatched are put into a pond or ponds by themselves 

 and given finely chopped meat of a fish like the pilchard. This is 

 continued through September. In October Trionyx ceases to take 

 food, and finally burrows into the muddy bottom of the pond to 

 hibernate, coming out only in April or May. The young are called 

 the first-year ones until they come out of their winter sleep, when 

 they are called the second-year young. At first the same kind of food 

 is given these as that given to the first-year young, but gradually 

 this may be replaced by that given to older individuals, namely, 

 any fish-meat or crushed bivalves, etc. From the third to the fifth 

 year, inclusive, the young need not be kept in ponds strictly accord- 

 ing to age, but may be more or less mixed, if necessary. The young 

 of these years are also the best and most delicate for eating, and 

 are the ones most sold in the market. In the sixth year they reach 

 maturity, and may begin to deposit eggs, although not fully vigorous 

 till two or three years later. How old these snapping-turtles live to 

 be is not known. Those one foot and more in length of carapace 

 must be many years old. The following table gives the average size 

 of the carapace and the weight of the young: 



