80 Mr. H. J. Carter on the Sponges 



ferous CUona to tlie Zoophytes, from the form of its papilla, 

 probably, rather than from their fmiction. 



Others have since verified his observations, although not 

 altogether according with his conclusions ; and my introducing 

 the former again here from personal examination, must plead 

 for excuse only in the special object of comparison for which 

 this examination has been instituted. 



I have stated that the pin-like spicules are chiefly confined 

 to the papillas, where, under certain conditions, they project 

 beyond the sarcode, and under others are more or less covered 

 by it. They come under the designation of Dr. Bowerbank's 

 " defensive spicules," but seem no more to merit that appella- 

 tion than thorns on rose-bushes. If I might presume to assign 

 any special function to them, without infringing upon the 

 illimitable uses for which every object in nature is provided, 

 it would be that their chief service is to support the deli- 

 cate sarcode when spread out like branchial appendages, for 

 the purpose of aeration. Of the uses of the other spicules 

 with which the sarcode of CUona nortlmmhrica is charged, 

 both externally and internally, I shrink from even hazarding 

 an opinion. 



Lastly, I have above used the expression " so-called genus 

 Raphyrus,^'' of whose single species, viz. Uaphyrus Grijfithsiij 

 this beach has afforded me several large and living specimens 

 (one of Avhich I have at this moment in sea-water under exa- 

 mination) ; and I feel bound to state that whenever I have 

 compared it with a fine specimen of CUona celata found at 

 Exmouth by my friend Mr. Parfitt, who kindly presented it 

 to me, the result has. been a corroboration of Dr. Johnston's 

 vieAV, who regarded it as a free form of CUona celata, and a 

 complete subversion of the slender grounds on which Dr. 

 Bowerbank has made it a separate genus [op. cit. vol. ii. 

 pp. 215, 216). The specimen of CUona celata which I have 

 mentioned presents the same kind of raised areola, more or less 

 plugged w4th sponge-substance, over the hole of the oyster- 

 shell from which it protrudes, the same kind of cellular struc- 

 ture interiorly, and the same form and size of pin-like spicule, 

 with its slight capitate variations, as the so-called Uaphyrus 

 Griffithsii, which to me is but a coarse form of a sponge 

 which, not having the cavities of a shell to support it, has to 

 provide itself with a stronger architecture. 



I am not the first person, too, who has noticed CUona 

 northumhrica in this neighbourhood ; for it is mentioned by 

 my intelligent friend Mr. Parfitt in his paper on the " Marine 

 and Freshwater Sponges of Devonshire," printed in the 

 Trans. Dev. Assoc, for Advancement of Sc. & Lit. 1868, 



