HALICHOXDBIA. 113 



" Colour. In the dried state, dark purple. 

 " Habitat. Coast of Durham, 20 to 35 fathoms ; 

 Rev. A. M. Norman. 



" Examined. In the dried state. 



I 



" I received four small specimens of this sponge from 

 the Rev. A. M. Norman for examination. The largest 

 was two inches in length, one inch broad, and not quite 

 half an inch in thickness. The largest specimen was 

 composed of four unequal-sized nodulous elevations, 

 and there were indications of a similar character on the 

 smaller ones. The dermal membrane affords the most 

 efficient characters for the discrimination of the species, 

 the tension spicula and their mode of distribution 

 more especially so. In some few parts the slender, 

 acuate spicula are somewhat irregularly dispersed, but 

 by far the greater number of them are arranged in 

 elongated fasciculi, which most frequently run parallel 

 to each other, and from each of which the component 

 spicula are frequently projected at slight angles from 

 the central axis in an ascending direction. These 

 bundles are in many parts so numerous and so close 

 together as to almost appear as if the spicula were 

 felted together. The retentive spicula are also very 

 numerous, especially the smaller of the two descrip- 

 tions of them. The larger forms are comparatively 

 few in number, and are readily distinguished from the 

 smaller series ; they are all of the same size as nearly 

 as possible. Several of them measured -g^- 5 - inch in 

 length, while the average size of the smaller ones was 

 3^-7- inch in length, and no gradational intermediate 

 forms could be seen connecting the two groups. Both 

 forms when in situ were attached to the surface of the 

 membrane by the middle of their curved shafts, so that 



VOL. iv. 8 



