76 ART. 1. — i. IJIMA : HEXACÏINELLIDA, III. 



to 230 1^. Siicli large discohexasters are not iincommonly fouiid 

 together with the second variety. 



As a fourth variety of discohexasters may be mentioned the 

 form shown in fig. 6, PL IV., which form is but rarely met with 

 in the parenchyma. It is characterized by very slim terminals, 

 grouped in separate, narrow and outwardly somewhat expanding 

 tufts. The terminal discs are rudimentary and piuhead-like in 

 appearance. The diameter, in one that I measured, was 144 /i. 



The delicate sigmatocome, which I have discovered in even 

 the smallest specimens of Cli. cavernosa at my disposal, has not 

 been found in the j^resent species. 



The second and much smaller specimen, which I refer to 

 the present species, is, I should say, essentially the same in spicu- 

 lation as the type, but with such jDoints of deviation as are 

 indicated below. 



None of the dermalia show spines on the paratangential rays. 

 This however I consider as due to the young state of the specimen. 

 Probably the spines develope after the sponge has come nearer to 

 maturity. 



Of the discohexasters, the commonest form (PL V., figs. 15 

 and 16), corresponding in general shape to that which I have 

 called the first variety in the type s])ecimen, has a smaller 

 number of terminals (usually 3 or 4) to each principal. Diameter, 

 54/>« and upward to 100,« or over. — The second variety of the 

 type seems to be wanting here ; but ])erhaps it is to be considered 

 as being represented by the larger of the rosettes that I have 

 just now compared to the first variety. — The third variety is well 

 represented though not in abundance ; an example of it is shown 

 in fig. 14, PL V. Diameter, 200/^. The discohexasters thus far 



