ACTINOPODOUS HOLOTHURIOIDEA. 259 



On the ventral trivium, pedicels are distinctly two-rowed and 

 somewhat crowded, while on the dorsal biviam tliey are rather 

 sparse, although occurring likewise in two rows, so that the dorsal 

 and ventral surfaces can be easily distinguished from the outside. 

 The calcareous ring is as given by Ludwig (1887, Taf. XV., Fig. 

 12). In one specimen I have detected one stone-canal on the dorsal 

 mesenterium, and one Polian vesicle in a more ventral position. 

 In another specimen, there were two Pohan vesicles present. We- 

 tractors are attached to the body-wall behind the middle of the 

 body. 



The calcareous deposits are exactly as given by Ludwig. 

 Very characteristic huge button- shaped plates with holes and 

 spines are found scattered in tlio perisome. In the pedicels and 

 around their base there occur longisli supporting rods with enlarged 

 and perforated ends. Ludwig has described from the pedicels 

 another kind of supporting rods, viz., more or less irregular plates 

 Avith many holes, among which the four central ones are distinctly 

 recognizable as such. Plates of this description are not found in 

 my specimens, except in those from Amakusa (No. 1633). hi 

 the latter specimens, there occur plates which are exactly like 

 those figured by Ludwig (Taf. XV., Fig. 14). 



Tentacles are 20 in number. As given by Ludwig, Bell and 

 Bedfoed, they are of various sizes, and are arranged in two circles. 

 In detail, I find their arrangement somewhat different from that given 

 by Ludwig (Taf. XV., Fig. 16) or by Bedfoed (1899 a, p. 843). 

 As I have made it out, the arrangement is as indicated in textfi^r. 52. 



The specimens agree so well with the description of Psmdocucumis 

 theeli given by Ludwig (1887, p. 1236), which species was later 

 recognized by the same author (1888, p. 815) to be identical 

 with Sempee's Cucumaria afncana or Psmdocucumis afrlcana 



