R. OKINOSEANA. MISCELLANEOUS NOTES. 249 



following three points in the spiculation of the tyjoe of R. decora : 

 1) The absence of oxyhexasters, which had been mentioned by 

 me as present in the Japanese species ; 2) the occurrence of large 

 and strong oxydiactin parenchymalia principalia (15-20 mm. 

 long, 100-200/^ thick), of which I had made no mention; and 

 3) the f\ict that the outer radial ray (120 /-< long) of the dermalia 

 was not particularly short, wliereas I had called it short in my 

 sj)ecies. 



As regards the first point, it is to be remarked that the 

 oxyhexaster and the oxystauraster, as they occur together in 

 li. ohinoseana, are so closely similar, except of course in the 

 point indicated by their names, that they scarcely deserve to be 

 made into separate categories of much systematic significance. 

 Moreover, the oxyhexaster occurs only occasionally and in 

 numbers which, though subject to variation according to indivi- 

 duals, may be said in general to be insignificant in proportion 

 to those of the other oxyasters. It may therefore under certain 

 circumstances be easily overlooked ; and besides, I think that in 

 individual cases it may even be really entirely wanting, without, 

 on that account alone, affecting the specific status. 



The second and the third point will have lost their weight 

 as distinctive specific characters from what I have given in this 

 Contribution for the size of the S2)icules in question from R. 

 okinoseana. One point concerning the dermalia seems to require 

 a remark. These were described and figured by Schulze as 

 tolerably uniform in size and in the strength of the rays. This 

 is also the case in my specimens so far as those on the flat or 

 depressed areas of the sponge-surface are concerned; it is on the 

 ledges, especially toward their edges, that the dermalia are sub- 

 ject to a considerable variation in these respects. That Schulze 



