there- is u circle of rather sjiiuli lioles around the central (jjteii- 

 iii;,', but in coiiqdcte' ones this cii'cle is (;fteu iuteri-ii])te(l. 'J'he 

 spire is built of four rods with a transverse beam and terminates 

 in a crown with 12 — 10 or more teeth. The buttons (d) have 

 mostly tlnx'O pairs of openings with tlie mai-gin decidedly crenate. 

 There ai'e knobs 0)i the middle beam, and very often other parts 

 are also beset with the same. Tlie calcareous bodies in the ventral 

 perisome are ]iliim]>er than those in the dorsal, so that the 

 holes are smalli'r. in the small Liu-Kiu specimens there are, be- 

 sides the tables of the same shape, some others with much 

 larger disk but compaiatively small crown and with two or more 

 circles of small holes around the central opening in the disk. It 

 seems therefore ^jrobablc that in this species also the young 

 animals have taljles that are larger and more complete than those 

 in the old. 



The anus ajipears to be stellate, and is surrounded by five 

 groups of small papillae. I'olian vesicle one. Stone-canal, atttiched 

 to the right of the dorsal mesentc'ry, very large, long and band- 

 like, having the cliaractcristic appearance described by Selenka 

 (1807, p. 3.'}3, Fig. 71 x). Its wall contains felt-hke fibres which 

 apixiar to me to be of an elastic nature and not calcareous. 

 Calcareous i-ing, as shown in a of the textligure. Even in well- 

 preserved specimens I can not discover any f 'uvierian organ, which 

 is probably wanting in this sjxicies. 



From the foregoing account two interesting facts stand out : 

 1) the end-plates of both the dorsal and the ventral ambulacral 

 apijcndages arc more develo|xid in the young than in the old in- 

 dividuals, and 2) among the calcareous deposits tlie tables are 

 larger and mijrc completely built in the young than in the old 

 individuals. From the first of these facts, it is not entirely cor- 



