142 BRITISH SPONGIAD.E. 



" I received a single specimen of this species, three 

 inches in length and one and a half inch in width, 

 embracing numerous slender stems of a zoophyte, so 

 that the specimen assumed the form of irregularly 

 inosculating branches, occasionally having upon them 

 nodous elevations with a single large simple osculum 

 at the apex ; other large simple oscula were dispersed 

 on the sponge, the margins of which were scarcely, if 

 at all, elevated above the dermal surface ; some of the 

 oscula were two lines in diameter. The minute 

 rugosity of the surface is produced by the projection 

 of the distal terminations of the primary lines of the 

 skeleton beyond the dermal surface. The porous 

 areas were visible in many parts by the aid of a lens of 

 two inches focus. The dermal membrane has no 

 special spicula appropriated to it. The dermal areas 

 are most frequently aspiculous, but occasionally a few 

 stray skeleton spicula are dispersed on their surfaces. 

 The skeleton-rete is rather irregular, and the number 

 of spicula in the primary lines vary to a considerable 

 extent, and they are rarely so few as to allow of their 

 being counted. The secondary lines are also irregular. 

 A single spiculum frequently suffices to connect two of 

 the primary lines, but they vary from one or two to 

 four or five loosely clustered together. The whole of 

 the spicula, whether stout or slender, are of the same 

 form fusiformi-acuate the proximal end always 

 being of less diameter than the middle of the shaft, 

 but whether adult or immature they vary to some 

 extent in their length. 



" This sponge is very simple in its structural charac- 

 ters, but it is well distinguished from other nearly 

 allied species by the forms of its spicula, and by the 



