iJ32 PLATE LXXVI. 



measurement of two of each form gave an average 

 length of j\ cr i ncn > both forms are of the same length. 

 They are perfectly and beautifully developed, and 

 require a linear power of about 700 to render them 

 distinctly to the eye. 



The skeleton fasciculi are very irregularly disposed, 

 and each fasciculus contains a great number of spicula ; 

 the length of the fasciculus seldom exceeds twice that 

 of a spiculum. The spicula are not mixed indiscri- 

 minately ; their bases are all seen at one extremity of 

 the fasciculus, while at the other end there are apices 

 only visible. At each end the spicula are slightly diver- 

 gent, while in the middle of the fasciculus the apices of 

 one series and the bases of the other are closely cemented 

 together. The skeleton spicula are all more or less 

 basally clavate, and their shafts are usually distinctly 

 fusiform. The interstitial membranes are abundantly 

 supplied with dispersed spicula of the same size and 

 form as those of the skeleton fasciculi ; very few 

 contort, bihamate spicula could be detected among them, 

 while on the dermal membrane they are abundant. 



Very few gemmules were visible. Since the above 

 description was written, I have received portions of 

 three small specimens of the species dredged by Mr. 

 Jas. J. Hillier, off Ramsgate. They vary in their size 

 and general aspect to a considerable extent from the 

 type-specimen from Jersey. Mr. Hillier in his letter 

 states : " It occurs as a mere film like a little fresh 

 glue on the tubes of Sabellaria;" and in a second note 

 he adds, " I have been able to get two more specimens 

 of the sponge of which I enclose pieces ; they are very 

 poor little things, but it seems almost impossible to peel 

 off any much larger than those sent, as it is such a 

 mere film on the very uneven tubes built up by Sabel- 

 laria, on which only I have found it. I have now met 



/ 



with it five or six times, and in no case have I seen it 

 more developed than that which I now send you ;" and 

 he subsequently adds, " when a piece is stripped off its 

 habitat it appears to shrink up as if elastic." This 



