218 ART. 7. T. IJIMA : HEX ACTINELLIDA, IV. 



crotubei'cnlate liexactins, amongst whicli there occasionally occur 

 pentactinic and even stauractinic forms. Its snrfaee in direct 

 contact with the substratnm is lined with a thin and particnlarlj 

 close-meshed reticular layer, the limiting basal-plate. — Of the 

 small basidictyonal mass shown in fig. 13, I have already spoken 

 on p. 210. 



STAUROCALYPTUS HETERACTINUS Li. 



PI. XI., figs. 1-10. 

 Staurocalyplus heteradinvs. Ijima, '97, \). 50. 



This sjiecies was described liy me in '97 from a single specimen, 

 A second specimen has not been obtained. 



The type-specimen (PI. XI.,' fig. 1 ; S. C. M. No. 409) comes 

 from a depth between 501 and 572 m. It is of the size of a bean 

 and represents a strongly laterally compressed pouch, measuring 

 21 mm. long and 10^ mm. broad in one direction and 6 mm. 

 broad in another. On one side of the upper rounded end is the 

 small oval-shaped oscuhim with its thin simple edge. The op- 

 posite end shows two processes with torn off terminations. Both 

 these processes probably served to fix the sponge to the substratum. 

 Thickness of wall at the middle of the body, about 21 mm. 

 Possibly the specimen is a young individual. 



The external surface is tolerably smooth, being without pros- 

 tals of any kind. Examined under the hand-lens, there are seen 

 to proceed upwards ft'om the basal processes obliquely running 

 and intersecting strands of rather coarse fibers which build up 



