78 A MONOGRAPH OF THE 



to the axis of the sponge, but I have never observed them 

 to assume a backward direction. These spicula are of 

 great size in comparison with the dimensions of the sponge, 

 frequently projecting beyond the surface of the head to 

 the extent of one and a half, and sometimes twice the 

 amount of its greatest diameter ; and what is rather re- 

 markable, it often occurs that the hemispherical heads of 

 the acuate, and the globular heads of the spiculate spicula 

 are the distal instead of the proximal portions of the 

 spicula; and in one instance, among the projecting spicula, 

 was an enormous triradiate one, having one ray based on 

 the top of the head of the sponge, the other two being 

 projected from its apex. I have been unable even with a 

 high microscopical power to detect either oscula or pores. 

 Nor have I succeeded in separating any portion of the 

 dermal membrane from the sponge, but seen in situ it is 

 evidentlv thin and translucent. 



I first obtained this interesting little species from Mr. 

 Tumanowicz, of Hastings, who informed me that he received 

 it from the fishermen trawling off that coast, at the 

 Diamond Ground, in about twenty-five fathoms ; he has 

 also found it on zoophytes, cast up on the beach after 

 severe storms ; we may, therefore, consider it as a deep 

 sea species, from seven or eight to twenty-five fathoms. 

 Halecium Beanii appears to be its favorite location, and 

 on this zoophyte it is usually found in great abundance. 

 He has also found it but in much less quantity on Plumaria 

 falcata, and cristata, and Sertularia, argentia, operculata, 

 and abietina ; a few specimens only have been found on 

 Alga, Phi/Uophora rubens, and Plocamium coccineum. 

 When fresh from the sea, he states it is of a translucent 

 bluish white colour. I have attached his name to it as an 

 acknowledgment of the good service he has rendered to 

 science by his indefatigable pursuit of marine natural 

 history, and of the kind and liberal assistance that I have 

 at all times received from him. I have also subsequently 

 received specimens of this species from Mr. Alder, of New- 

 castle-on-Ty ne > an d from my kind friend Dr. Johnston, of 

 Berwick-on-Tweed. 



