270 I. IJIMA : HEXACTINELLIDA. I. 



part of the specimen exhibit the synapticiihir fusion of the 

 megascleric elements. Much less frequently such fusion is to be 

 met with in about the middle, and none at all still higher 

 above. Were the base of the specimen preserved, just the same 

 condition as has been known from R. phœnix in regard to the 

 fusion of spicules in that region would undoubtedly have been 

 found. 



The said condition of the base admits, as was remarked by 

 Schulze ('87), of the occurrence of several specimens growing 

 one within another, each inner one representing a younger 

 generation seated within the dead skeletal remnant of the pre- 

 ceeding generation. O. Schmidt ('80) observed such occurrences 

 when he first described R. phwiiix, which specific name he chose 

 on that account. Topsent ('96) mentions a case in which as 

 many as fine generations were represented in the manner noticed, 

 and recently Schulze ('99) has added still anotlier instance to 

 the list. It scarcely needs to lie remarked that this piling up, 

 as it were, of successive generations, forms no specific peculiarity 

 of the species. In R. okiiioseana I have found it a very com- 

 mon occurrence that the young specimens are attached to the 

 dead skeletal stump of the same species. So also the two indivi- 

 duals I have described of R. homeyamai are attached, not one 

 within the other, but close together, side by side, on the basal 

 mass of an individual long dead and destroyed. 



SnCLLATION. 



The spiculation shows an especially close agreement with 

 that of the species last describ 'd. 



Excepting the large oxypentactins common to the sieve-plate 



