ACTINOrODOrS HOLOTHURIOIDEA. 259 



On the ventral tvivimu, pedicels are distinctly two-rowed juid 

 somewhat crowded, while on the dorsal Itivimn tlicy are rather 

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

 and vonti-al surfaces can be easily distinguished from th(^ outside. 

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

 12). In one specimen 1 have detected one stone-canal on tlie dorsal 

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

 In another specimen, there wore two Polian vesicles present. He- 

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



body. 



The calcareous deposits are exactly as given by Tjinvio. 

 Very characteristic huge l)utton- shaped plates with holes and 

 spines are found scattered in the ix-risome. In the pedicels and 

 around their base there occur longish supporting rods with enlarged 

 and perforated ends. Ludwig has described from the pedicels 

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

 with 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. K'.^r)). In 

 the latter specimens, there occur plates which are exactly like 

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



Tentacles are 20 in number. xVs given by Ludwig, ]5ell and 

 Bedfokd, they ai-e of various sizes, and are arranged in two circles. 

 In debvil, I iind tlieii' arrangement somewliai diflerent from that given 

 by Ludwig (Taf. XV., Fig. 16) or by 15edfoiid (1899 a, p. 843). 

 As I have made it out. the arrangement is as indicated in textfig. 52. 

 The specimens agree so well with the description of rseudonicwius 

 thcdi given by Ta-Dwi.; (18S7, i*. I'lo^), which species was later 

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

 with" Semper's Cucumaria afrkana or Pszudocucumis africana 



