HABITS AND LIFE-IIIS TORY OF STICHOPUS JAPONICUS. 



'5 



It will be seen from the above table that the grow th of the first 

 year young is steady, rapid, and comparativey regular. The lot into 

 which the largest number of individuals dredged in a given month have 

 to be placed, is found to be larger and larger in size with every month, 

 and the maximum and minimum sizes of each month also steadily grow. 

 And for each vertical column, the number placed in it is at first small, 

 then gradually increases until it reaches a maximum, and then decreases 

 again. For instance, for the column 13.5x2.5, there is only 5.88 % 

 for November, this gradually increases up to 32% in February; it then 

 gradually diminishes to 2% in June. The best month for securing the 

 young holothurians of that grade is therefore February. 



Four observations given as made at Kanagavva early in the year 

 1894 go on the whole to confirm the results obtained from October, 

 1894 to June, 1895. 



Two observations given last as made at Kanazawa show that there 

 is a larger number of younger ones in that locality than in the cor- 

 respending month at Kanagawa, and there are quite small ones as late 

 as August. This is probably due to two causes: (r) there may be actual 

 differences in the duration of the breeding season. This, I, however, 

 think, can hardly be of much weight for Kanazawa is only a few miles 

 from Kanagawa and is in the same Bay of Tokyo. The stronger reason 

 is probably this: (2) that here, instead of depending on a dredge, I 

 was able to wade in, turn over rocks and pick up all the holothurians 

 that were to be found, thus securing young ones which are probably not 

 caught in dredges. 



The differences in the size of the young arise from at least two 

 reasons: (1) from the congenital causes, (2) from the fact that some 

 are hatched early in the breeding season, being thus ahead of the later 

 ones sometimes by three or four months. 



Finally the above table shows that the maximum size which the 

 young holothurians attain at the end of the fist year is about 25 cm by 

 5 ««, the actual measurements of three largest individuals being 26 cm, x 

 4 cm., 25 £7«. x 4 and 220/1. X 5 cm. This growth must certainly be 



