ACTINOPODOUS HOLOTHUEIOIDEA. 221 



decidedly pentangular, the median ventral ambulacrum becoming 

 prominent. These five angles correspond to the five valves by 

 which the mouth is closed. The three ventral ambulacra are 

 distinct, each showing about two pedicels standing side by side at 

 the ends, but in the middle more than two. In the dorsal lateral 

 rows of papilla?, the bases of these are surrounded by spiny elevations 

 formed by calcareous plates which make the whole body stiff and 

 hard. All the intei'ambulacra are naked and in most specimens 

 darker colored than the ambulacra. Tentacles ten ; two ventral 

 tentacles smaller than the rest. Calcareous ring simple : I can not 

 discover that any of the joints are narrower or more crowded than 

 the rest. Polian vesicle one. Stone-canal one, attached to the 

 dorsal mesentery. Genital tubes unbranched. Retractors inserted 

 at about 1/4 of the body length. Anus with five small teeth. 

 Calcareous deposits of three kinds : (i) small reticulate hemispheres, 

 (ii) knobbed buttons, and (iii) large plates. In addition to these 

 there are found (a) supporting rods, (h) tentacular supporting rods, 

 and {c) distinct end-plates. 



Localitij :■ — -Cnpe of Gool. Hope (earlier authors) ; Boweu (Ludwig '74) ; 

 Sydney (Ludwig 74) ; Port Jackson (Beix '86; ; Port Molle (Bell '86) ; 

 New South Wales (Lajipeet '86j ; West Austraha (Lampeet '86) ; Amboina 

 (Ludwig '88, Sluitise '94) ; Bahia (Théel '86) ; Billiton (Sll^tee '87)^; 

 Ceylon (Pearson '03) ; East Coast of Japan, from Hokkaido to Satsuma. 



51. Colochirus hiornatus v. MAEE^'ZELLEE. 

 (PI. 7HI, fig. 73; textfig. 40;. 



Colocldrus inorimtii.s v. Maeenzellee 1881, pp. 130 — 2, Taf. Y., Fig. 7. 

 — Lampeet 1885, p. 127.— Théel 18S6r^ pp. 77, 120, PI. YL, fig. 8.— 

 Lampeet 1889, p. 824. 



Thyone hiornntn Ludwig 1889—92, p. 346. 



