ART. 8 A NEW VARIETY OF SPONGE WILSON AND PENNEY 7 



Discocasters IQOfi diameter; protuberances representing the six 

 primary rays large; terminal disks of secondary rays comparatively 

 large and usually with six marginal teeth. 



R. (Acanthosacciis) tenuis (F. E. Schulze, 1899, p. 66), coast of 

 California. Autodermalia, pentacts, stauracts, and diacts. Auto- 

 gastralia, oxyhexacts; free ray QOOfx to 800/a long and over, more 

 strongly spinose than the other rays; latter rays 200/^ to 300|U, long. 

 Oxyhexasters represented only by the (derived) oxyhexact form 

 150/A to 200;u diameter. Discoctasters SOO^u, diameter; main rays 

 short, sometimes exceedingly short; terminal rays numerous, long 

 and slender, bearing end disks having 5-6 marginal teeth. {Acantho- 

 saccus F. E. Schulze 1899, p. 65, was merged in Rhabdocalyptus by 

 Ijima 1904, p. 128.) 



R. mollis F. E. Schulze (1887, p. 155; Ijima 1897, p. 50; Ijima 1904, 

 pp. 253-301), Japan. Autodermalia, diacts with a few stauracts and 

 pentacts. Autogastralia, oxyhexacts, rays all similar. Oxyhexasters 

 with rays conspicuously barbed proximally. Discoctasters 130ju, to 

 176//, diameter. 



R. caf Hiatus Ijima (1897, p. 51 ; 1904, pp. 276, 302) , Japan. Auto- 

 dermalia predominantly diacts. Autogastralia predominantly hex- 

 acts, rays all similar or free ray twice as long as the others. Oxyhex- 

 asters 106/A to 136//. Discoctasters small, 82// to 106// diameter; 

 terminals much longer than the main rays, in a solid bunch and 

 distinctly flaring. 



R. motor Ijima (1897, p. 52; 1904, pp. 238, 301), Japan. Height 

 may reach almost 3 feet (859 mm.). Autodermalia, stauracts. Auto- 

 gastralia, oxyhexacts, rays all similar. Oxyhexasters 180// to 280// 

 diameter; principals very short or obsolete. Discoctasters 180// to 

 240// diameter. 



R. unguiculatus Ijima (1904, pp. 268, 302), Japan. Autodermalia, 

 diacts with a few stauracts or tauacts (3 rayed forms). Autogas- 

 tralia, oxyhexacts; free ray much longer than the others, 440// to 

 550//; parenchymal ray 230// to 300/j.; tangentials 275// to 330//. Oxy- 

 hexasters 130// to 160// diameter. Discoctasters 143// to 190// diam- 

 eter; terminals much longer than main rays; end-disks with margi- 

 nal teeth which are largest and strongest on side that is turned away 

 from axis of the tuft of terminals. 



R. plumiodigitatus Kirkpatrick (1902, p. 220; syn. R. lophodigi- 

 fatus Kirkpatrick 1901, p. 458), South Africa. Shape, that of a 

 subglobular cup. Autodermalia and autogastralia, diacts 600// to 

 1,000// long. Oxyhexasters 90// to 100// diameter. Discoctasters of 

 two forms : large ones, 130/x to 160// diameter, main ray bearing 6-8 

 very much longer terminals; small ones, 60// diameter, with more 

 divergent terminals. Microdiscohexasters not observed. 



