72 THE SPONGES. 



3 to C in number, 100-120 [x long, are nearly straight and are covered 



with exceedingly small denticulations. With regard to the precise 



shape of the distal rays, the spicides vary between two extremes. At 

 one end of the series are found scopulae (Fig. 3, Plate 9), in which 

 the rays are cylindrical, 4-5 /a thick, passing above into large rounded 

 heads 12 fx in diameter, which bear recurving spines. This type is like 

 the corresponding scopula of subspecies tubuliferum, except in its greater 

 size and in the comparative straightness of its terminal rays. The other 

 extreme is represented by a scopula (Fig. 1, Plate 9), usually one of 

 the longest, in which the terminal rays are very stout and taper con- 

 spicuously from below upward. The lower diameter of the ray is about 

 12 /x, the upper diameter 6 /x, and the ray ends in a smooth and not 

 enlarged, rounded, or conical extremity. Immediately below the extremity 



the denticulations are enlarged and form short recurving spines. 



Between these two extreme types of gastral scopulae are found intermediate 

 forms in which the distal rays taper slightly or considerably from the 

 base upward, and end in strongly or very feebly spinose heads which vary 

 from a very small size, 6 /a in diameter, to a large size, 12 /a in diameter. 

 The extreme apex of the head may be smooth, or denticulations may be 

 here developed. 



Eurete, sp. 



At Stations 3370 and 3380, 4 specimens belonging to Eurete were 

 obtained. The specimens are completely macerated, the dictyonal 

 framework alone remaining, and thus do not admit of a more precise 

 identification. 



