with his accustomed liberality, at once gave me the specimen 

 figured on Plate I, and accorded me permission to describe 

 it. In dedicating it to my friend I take this opportunity of 

 thanking him for the many kindnesses Avhich he showed me 

 while in Portugal. The memory of a delightful Sunday 

 spent with him at charming Cintra will ever remain with me. 

 The museum under his care is one of the most interesting 

 in Europe ; the more especially interesting on account of the 

 fine collection of native species brought together by the per- 

 severing energy of Professor Bocage and his admirable assist- 

 ant Sig. Capello. It is also rich in species from the Portu- 

 guese settlements abroad, and this sponge formed but one 

 of a fine series of invertebrata from the Cape de Verd Islands. 

 The nearest ally of this species is undoubtedly A. beatnoc. 

 Gray, audit is quite possible when we know more about both 

 forms, and when they have both been examined in a living 

 state, that they may prove but varieties of the same species. 

 This is is possible, but for the moment I think not probable. 

 There is a certain regularity of form in the sponges which 

 have a non-elastic siliceo-fibrous skeleton, which I venture 

 to think will be found to be in a measure characteristic of 

 the species. But apart even from this consideration, the 

 areas forming the skeleton in A. Bocagei are much more 

 regularly hexagonal than those in A. beatrix. The spines 

 on the bosses are very much longer in the former than in the 

 latter species; in it too the central cavity is larger. The 

 reticulated network-like lid is much more radial in its com- 

 position than in A. beatrix. The bosses of the rays of the 

 body-skeleton are often knobbed, and there is an apparent 

 absence of porrecto multiradiate spicules so characteristic of 

 A beatrix. This fact I do not lay much stress upon, as it 

 may arise from an error of observation. I have, however, 

 met with these spicules in every specimen that I have 

 examined of A. beatrix, and never in the many specimens 

 examined of A. Bocagei. This latter, too, is a much more 

 erect form than the former, and I should expect that when 

 the sarcode layer of both species is known that the spicules 

 of this layer may be somewhat different in both. I am in- 

 debted to Mr. Ford for the accompanying drawing which he 

 made for me in January, 1869. Circumstances have pre- 

 vented me from publishing a description of it sooner. Professor 

 Wyville Thomson has kindly forwarded to me portions of this 

 sponge taken in the recent cruise of H.M.S. " Porcupine." 

 He informs me that it was dredged living off" the south-west 

 coast of Ireland at a great depth. The portion sent to me is 

 a fragment of a dead specimen. But Professor Thomson 



