and two Esperiadgej^owi the West Indies. 269 



There is, of course, little or no description of them amongst 

 the British Spongiada;, because they do not belong to the 

 British Isles ; but what little is stated of them is so contradic- 

 tory, that it had better have been omitted altogether. 



Thus, at p. 25, vol. i., the spicules of Ectyon sparsus are 

 said to be " entirely" spined ; at p. 125, " entirely and verti- 

 cillately," and at p. 275, in the index to the figures, " verti- 

 cillately," while hi the figure itself (289) they agree only with 

 the latter. Now all these are distinct terms for Dr. Bower- 

 bank's different kinds of spined spicules, as may be seen in 

 his "Terminology;" and had Ectyon sparsus any more than 

 one form of spicule, the contradictions might have been of 

 little consequence ; but as there is only one form, they are 

 most confusing and unsatisfactory. 



Again, in Acarnus innommatus (fig. 292), there is only 

 one kind of spicule recognizably figured, viz. the '' recurvo- 

 quaternate " form, and, but for the separate figures of this 

 spicule given in figs. 73-76 inclusively, we should not know 

 exactly what it was like; while there are no less than four 

 others unfigured (equally distinct and beautiful forms) in this 

 sponge, rendering it, above all others, the most exquisite little 

 spicule-combination of any sponges with which I am ac- 

 quainted. 



Lastly, Dr. Bowerbank states of this sponge (fig. 292), in 

 his " Terminology," that it is " a portion of the reticulated sur- 

 face of the sponge," having called the preceding figure (fig. 

 291) Hymeniacidon Cliftoni. Thus " the sponge " would 

 appear to mean Hymeniacidon Cliftoni ; yet at p. 33, vol. i. it 

 is stated to belong to his " Halichondroid tribe," which is 

 much more intelligible, if not much more correct. 



But Dr. Gray, who had nothing but Dr. Bowerbank's text 

 and illustration for his guidance, evidently did not know all 

 this, or he would not have placed this sponge, viz. Acarnus 

 innominatus, amongst his Tethyadaj. 



Under such circumstances I do not hesitate to give full 

 illustrations and descriptions of both these sponges with Dr. 

 Gray's names. 



The former, which is a very large specimen (being nearly 

 a foot long), is in the British Museum ; and the latter, of com- 

 paratively insignificant size, had grown upon the fragment of 

 calcareous debris (consisting of the remains of corals and the 

 like) at its base. Hence, knowing that the former came from 

 the West Indies (St. Vincent is suggested by Dr. Gray, who 

 requested me to describe the specimen), we have also the loca- 

 lity of the latter, wdiich Dr. Bowerbank has omitted, although, 

 curiously enough, Ectyon sparsus and Acarnus innominatus 



