l80 ART. 7. — ï. IJIMA : HEiACÎlNELLIUA, IV. 



rail out into a single normal terminal besicles showing near its base 

 the short and spurious rudiment of a second terminal. By one 

 short step of reduction, the oxyhexaster might change itself into 

 a hemihexastinose form with one uniterminal princijml. 



The discodasters may in general be said to have a diameter 

 of 130-213/^; the principal takes up nearly one half or some- 

 what less of the entire ray-length. Terminals straight, nearly 

 smooth, 2-5 in a tuft which broadens gradually and slightly 

 outwards. The sinaller discoctasters show six tuljercles on the 

 central node, l)ut the larger ones do not. Those in the subdermal 

 region are smaller than others in the subgastral ; the former 

 measuring 130-170/^, and the latter 17'j-21o/i, in diameter. The 

 specimen spicule shown in Contrib. III., PI. VI., fig. IG, is from 

 the subdermal space. (In -S'. dowl'myi the discuctaster diameter 

 is known to be 228-320 /', manifestly never falling below 200 n). 



Spherical iiiicrodiscoJiexnders (jf 1Ü//. diameter and of the 



usual appearance are found very sparsely distributed in tlie 



endosomal layer. I consider that they recpiire no S2)ecial de- 

 scription. 



STAUROCALYPTUS AFFINIS nov. sp. 



PI. XIII. and PL XIV., hgs. 14, 10, 17, 22-25. 



Staarocalypius Vowlituji in part. Ijima, '97, p. 53 ; 'gS, p. 53. 



This new species is based on two specimens in the Science 

 College Museum, which were at first — errorneously, I now^ think 



