SPONGIIDA. 627 



preparation, althougli he says that the range is great) ; and I do not 

 find in Schmidt's species the small multiradiate stellate which occurs 

 here ; the granulations on the surface of the disk are much coarser 

 in this species. In having lost the trifld head of the zone-spicule it 

 exhibits the same tendency as that which seems to have led in 

 AvMrina aa/ptus, Schmidt, to the loss of all tetraradiate characters. 

 Early stages of the acerate spicule (no. 3) exhibit the central in- 

 flation found in the young acerates of some Renierce and Spongillidce. 



51. Stelletta acervus. 

 Ecionemia acervus, Bowerhanh, P. Z. 8. 1873, p. 322. 



There appears to be only one form of minute stellate; those 

 stellates in which the arms are small, relatively to the body, seem to be 

 the young form of the longer-armed adult ; the arms are very slightly 

 capitate, as shown by Dr. Bowerbank's preparations and still more 

 plainly in the present specimen, and vary in number from about 5 

 to about 12. The small acerates are scantUy present in the cortex. 

 Dr. Bowerbank considered his specimen to have been originally 

 fixed, but the actual base was absent ; the present specimen is 

 decidedly free, and has an oval shape. 



Hah. Etoile Island, Amirante group, 13 fms. ' 



DistribiUion. Fiji Islands (Bowerbank). 



52. Stelletta purpurea, var. parvistella, nov. 



See Part I., p. 473, of this Report. 



A small oval specimen 7^ miUim. long, destitute of a vent, and of 

 a purple colour, undoubtedly represents this species in a somewhat 

 modified form. Thus the stellates do not exceed '0095 millim. across 

 the arms, and usually measure about "007 millim. , and the arms are 

 generally more numerous than in the Australian specimens. The 

 skeleton-spicules are also somewhat smaller, viz. : — diameter of shaft 

 of zone-spicule -032 miUim., of anchor about -023 millim., of acerate 

 about -025 millim. ; the arm of the zone-spicule curves boldly back- 

 wards, but does not make an angle in its course like that of var. 

 retroflesca, mihi. The small size of the skeleion-spioules is perhap? 

 partly due to the youth of the specimen. The variety approaches the 

 form obtained in the Arafura Sea the most closely. 



Sab. Providence Eeef, Mascarene group, 24 fms. 



