On the system of Phyllophorinae with descrip- 

 tions of the species found in Japan. 



By 



Hi rosili Ohshima, Rigakushi. 



With Plate I and 7 textfigures. 



Having discovered in the Holothurian material at my disposal a 

 number of specimens referable to the interesting species Pseîidocuciimis 

 japonicns (Bell), my attention was directed to the comparative study 

 of tentaculation in the so-called " polychirotous " Cucuniarids. In the 

 present paper will be given my views concerning the system of the 

 group, arrived at from my studies, to be followed with descriptions of 

 the species found in the Japanese waters. 



I. On Tentaculation and its Bearing on the 

 System of Cucumariidae. 



1. Observations* 



i. Pseudocucumis aj 'ricami s (SEMPER). 



A goodly number of specimens belonging to this species stood at 

 my disposal, so that my observations on tentaculation were made 

 chiefly on it. 



In regard to number, size and arrangement of tentacles in this 

 species, records have been given by LUDWIG [24> P- 1237, Taf. XV., 

 Fig. 16; 26, p. 96, Fig. 11], Bedford [4, p. 844, figs. Ill, b— e] 

 and MiTSUKURl [32, textfig. 52]. According to these authors, the 

 two small tentacles, situated in a pair in the midventral radius, are 

 either equal to each other in size and stand side by side, or are of 

 different sizes, in which case the smaller is situated at a position 



