A New Fresh-water Nemertine from Japan 



[Stick osi emma grandis). 



By 



Dr. Iwaji Ikeda. 



With Plate IV. 



On March 29th, 1909, in the Botanic Garden of the Hiroshima 

 Normal School, I have casually discovered a small worm of a leech- 

 like appearance, living in the soft water-covered mud in a vessel 

 which was planted with the aquatic plant Lisichiton kamtschatense 

 Schott. When first dug out, it was found entirely contracted within 

 its own mucous secreta, but a little later it cast off the latter and 

 began to creep about, meanwhile unmistakably revealing itself to 

 be a nemertine. Subsequent searches enabled me to obtain about 

 sixty specimens out of the same vessel. The discovery seemed to be 

 of much interest, for, to my knowledge, there previously existed no 

 record of the occurrence of a fresh-water nemertine in Japan, a belief 

 which is shared also by Mr. Takakura of Tokyo, who has long been 

 engaged in the study of Japanese nemertines. Moreover, from subse- 

 quent study, it turned out that the nemertine represented a hitherto 

 undescribed species of Stichost vana. I propose to call it 5. grandis. 

 The worms, which were kept in captivity, began to spawn on April 

 19th, and continued to do so till the end of June, when I had to 

 leave Hiroshima. Then, all the material on hand — both the adults 

 and the eggs — were preserved and placed in storage for future 

 investigation. 



Later, in the Zoological Laboratory of the University of Cam- 

 bridge, England, I was able to take up the study of the above 

 material. As the result, I have found some new points of interest in 



