56 



T. IJIMA. 



present ; hexactin-shaped oxyhexasters probably not absent. It fre- 

 quently happens that in a dilopbous ray, a third terminal is represented 



by a spurious rudiment. 



Microdiscohexasters of usual structure found in tolerable abundance 

 in the subgastral region. 



Autodennalia are predominatingly pentactins, but stauractins are 

 by no means unfrequent. Occasionally triactins and diactins, rarely 

 monactins. Kays sparingly rough, not always quite straight ; 110-155/2 

 long ; usually less than 5ft in breadth at middle. 



Hypodermal strands contain besides numerous slender diactins 

 with tuberculated centre, medium-sized pentactins whose slender rays 

 are smooth except at roughened ends. Head of pentactins not para- 

 tropal. It is not known whether these pentactins are ever extruded 

 beyond the external surface. 



Autogastralia are oxyhexactins with sparingly rough rays of about the 

 same thickness as the autodennalia. Free proximal rays as long as 230// ; 

 other rays somewhat shorter. According to Schulze, the autogastralia 

 line the ^astral surface as also the surface of the wide efferent canals. 



7. Stauròcalyptus heteractinus, n. sp. 



This species is founded on a single bean-sized specimen from Saga- 

 mi Sea. It represents a strongly compressed pouch with a small simple- 

 edged osculum on one side of the upper end. Texture as in other species ; 

 without prostalia pleuralia of any sort. 



Discoctasters especially common near the gastral surface. Radius 

 55-100//. Terminals 2-7 to a principal ; straight, diverging. Disc 

 minute and pin-bead like. 



Oxyhexasters 53-57// in radius. Most of those situated in deeper 

 parts have two-forked rays with excessively short principals ; terminals 

 stout, straight, rough with minute prickles, which are more prominent 

 and inwardly turned near base. Peripherally situated oxyhexasters have 

 somwhat longer principals, each with 2-4, usually 3, rough-surfaced, 



