THE SPONGES. 69 



nals 36-48 fx. In yet another specimen, along with spicules in which 

 the principal ray is 4-6 fx long and the terminals about 40 /u, long, are 

 many spicules with relatively long principals. In these the length of the 



principal reaches 8 fx, while the terminals are 28-32 /x long. There 



are 2 or 3 terminals to a principal. The principal is smooth, the termi- 

 nals faintly roughened. The terminals diverge considerably, and are 

 nearly straight, or only slightly outcurving, delicate, and tapering to fine 



points. Oxyhexasters occur in which some, or all, of the principals 



bear but one terminal each, a slight "knee" usually marking the passage 

 of the principal into the terminal. 



These sponges resemble in all other respects the specimens described as 

 Eiirete eredum iuhiUfenim, and which were taken at the same two stations as 

 the above. While I have separated the two groups of individuals, and 

 designated them as subspecies, it seems to me quite possible that they are 

 merely classes of individuals which differ in respect to a quality of individual 

 variability. Their detailed resemblance in respect to the other structural 

 features suggests that this is the case. 



Eurete erectum gracile, subsp. nov. 



Plate 8, Figs. 4, 5, 8, 9 ; Plate 9, Figs. 1, 3, 5. 



Diagnosis. Axial part of sponge body forms a very elongated spiral. Distal ray of 

 the dermal pinules very thick. Tangential rays of the gastral pentacts and hexacts beset 

 all over with minute sharp prickles. With onychasters. Characteristic dermal scopulae 

 are small forms, in which the distal rays' are minutely denticulate, and taper from the 

 base to the apex, which is smooth and not enlarged. Gastral scopulae are large forms, 

 600-1500 fi long ; distal rays slender and with large heads, or stout and tapering from 

 base to apex, and without heads. 



Station S380, 4 specimens. 



In these specimens the upper and lower ends of the sponge are not 

 present. The axis. Fig. 5, Plate 9, forms a very elongated spiral, which 

 varies but little in diameter, being 8-10 mm. thick over a length of 

 150 mm. The cups are much broken, but it may be seen that they are 

 mostly undivided, and that they have a flaring wall. There are, however, 

 some cases in which the cups are partially or completely bifurcated, and 

 it may be seen that in the bifurcation of the cups the same peculiar ridges, 

 or tubular structures, are produced that have been described for Eurete 

 eredum tuhuUfervm. And extending from the cups onto the axis similar 



