20 ART. ". 1. IJIMA : HEXACTINELLIDA, IV. 



SCYPHIDIUM F. E. Sch. 



Saccular or vasiform, tliick-walled, firmly attached 

 by contracted base; showing a disposition to produce 

 buds on the wall. Parenchymalia exclusively diactins. 

 Pentactinic hypodermalia with paratropal or regularly 

 cruciate, smooth or finely shagreen-like paratangentials, 

 without spines. Dermalia, stauractins or pentactins, 

 or both ; rough-surfaced. Clastralia, regular hexactins 

 with rough rays; forming a continuous layer over ex- 

 current canalar apertures. Oxyhexaster normal, hemi- 

 hexactinosc or hexactinose. Discohexaster distinguish- 

 able into two forms differing in size, but botli being 

 s})herical in shape. These two forms may grade over 

 into each other; at all events, the smallest discohexas- 

 ter is only about half as large as the largest or even 

 much smaller. 



The genus was first instituted by F. E. Schulze ('oo) to 

 receive the species septenlricmale from the Arctic Ocean. Two 

 forms occurrino; in the Saffiimi Sea and described bv me before- 

 in brief under the names of RosseUa longispina ('96) and 

 Vitrollula namiyei ('98) I now consider to be generically uuitable 

 with Scyphidiuni septentrionale F. E. Sch. Further, the speci- 

 men from Messier Channel (Southern Chile), which had been 

 described by F. E. Schulze ('99, p. 43) as Bossella sp. without 

 receiving a specific name, likewise seems to be referable to the 

 same genus and to rejDresent a species especially closely related 

 to my ticyphidiuDL namiyei. 



Under Rossella I put together the species (Nos. 1—1 of the 



