FEB 10 1904 



Notes on the Habits and Life-History of 



Stichopus japonicus Selenka. 



BY 



K. Mitsukuri, Ph. D., Rigakuhakushi. 

 With 4 Woodcuts. 



By the request of the Department of Agriculture and Commerce 

 of the Imperial Japanese Government I spent a considerable time at 

 intervals in the years 1893- 1 897 making observations on the habits and 

 life-history of SticJiopus japonicus Sel. The following gives a summary 

 of the results of my investigations which were carried on mostly at 

 Kanagawa, supplemented by those at Kanazawa (Prov. Musashi), 

 Misaki and a few other localities. They have been withheld until now 

 with the hope of filling up some gaps in them, but as the 

 possibility of doing so in near future is somewhat remote, they are 

 now published with the hope that they may not be altogether 

 uninteresting. It is my pleasure as well as duty to record my 

 indebtedness to many persons who aided me in various ways in the 

 course of this work. Especially I would mention the late Mr. 

 NAOKATA Ishii of Kanagawa who with great kindness helped me to 

 obtain facilities for carrying on my observations at that town. Mr. O. 

 Sasaki, now of the Chiba Fisheries Experiment Station acted as my 

 assistant in the earlier part of the investigation. 



The breeding season of Stichopus japonicus ends with the latter 

 half of July. Larger and older individuals seem to get through spawn- 

 ing earlier than younger ones. As individuals finish shedding the 

 reproductive elements, they crawl into dark places found under rocks 

 and stones or otherwise produced. Here they cease to take food, their 



