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ISAO IJIMA. 



A) From the above table it will be seen that the regular discohexaster 

 is apparently the most constantly occurring variety. In a specimen from 

 Doketsba it constituted the only kind of hexaster to be found and was met 

 with in great abundance. In certain other specimens it was rare, requiring 

 a long search to find one. In one specimen it was missing altogether. 

 The discohexaster in question is a small form between 20 and 50// in 

 diameter, the size fluctuating in the same stock to the extent that the 

 smallest is of about half the diameter of the largest. Each short principal 

 bears 3-5 terminals, which in the smaller examples are quite fine, delicate 

 and minutely capitate, but in the larger ones may be moderately strong 

 and terminate with a small disk bearing a few, not always distinct, recurved 

 claws on the margin. However, in no case of the oriental specimens have 

 I found the claws to be of such a development as might induce one to call 

 the spicule an onychaster, as F. E. Schulze found them to be in some 

 specimens from the Indian Ocean. Usually the terminals are nearly straight 

 and spread out radiatingly from the end of principals ; but variation again 

 occurs in this respect, for, in a specimen or two I have found the terminals 

 to each principal form separately a more or less distinctly bell-shaped or 

 perianth-like group. Occasionally the discohexaster in question, but 

 especially the larger examples of it, may be found in the form of a hemi- 

 discohexaster, in which none of the principals are specially elongated. 



B) The regular oxyhexaster was met with in many specimens, but 

 again in varying numbers. In only four specimens, out of the twelve, I 

 have found none of it. The oxyhexaster is of much the same appearance 

 as the above regular discohexaster, except of course in the manner of 

 ending of the terminals. Diameter 32-S0/.4 (representative fluctuations in 

 different stocks : 32-56/i, 35-40^, 56-So/.!). Occasionally the oxyhexaster 

 likewise takes the form of a simple hemioxyhexaster. 



C) The elongate hemidiscohexaster and D) the elongate hemioxy- 

 hexaster often occur together, as do the regular discohexaster and 

 oxyhexaster, in the same stock in varying numerical proportion ; but 

 sometimes either of the elongate varieties, and more rarely both of them, 



