438 



that family under my hands, or leave it for some other person to 

 examine who might take up the group. 



Having lately had occasion to consult Messrs. Quoy and Gaimard's 

 work, and the essay of Mr. Dana, I became satisfied that the sub- 

 stance from the Azores could not be the Alcyonium glaucum or Al- 

 cyonium latum (Dana, Zooph. 623. t. 58. f. 6), which I had before 

 thought from recollection might be the case ; for these authors de- 

 scribe A. glaucum as soft and fleshy, and A. latum as "more rigid 

 in its texture than .4. glaucum" As Mr. MacAndrew's specimen is 

 hard, inflexible, and brittle, though very light, this induced me to 

 examine the specimen more carefully ; and I then found that the 

 supposed coral was a silicious sponge, covered below with a thin 

 fleshy envelope without any apparent apertures, and above with a 

 thicker fleshy coat, studded with large-sized, regularly-disposed, cir- 

 cular cells, which look like the cells of the Polypes in the two Al- 

 cyonia above referred to. The apertures are destitute of a radiating 

 lamina, and appear in their dry state to be subdivided into six or eight 

 small circular tubes, and have all the appearance of being the cells of 

 a pinnated tentacled zoophyte. The small part of the lower surface 

 of the spongy axis, which is exposed, is pierced with minute perfo- 

 rations, and the upper surface is furnished with groups of larger 

 pores, which, as far as I can judge without injuring the specimen, 

 are placed under the cells above described. There are grooves di- 

 verging from the small cylindrical perforations in one of the groups 

 to the perforations in the other groups. 



I have thought proper to call the genus after the gentleman who 

 discovered it, and who has been very liberal in doing all in his power 

 to extend our knowledge of zoology and geology, and has several 

 times placed his yacht at the command of scientific men, to assist 

 them in their researches. 



The genus may be thus defined : — - 



MacAndrewia. 



Cup-shaped, expanded, more or less sinuated or lobed, affixed by 

 a more solid dilated base, covered with a fleshy bark, which is fur- 

 nished with cells on the upper surface, supported by a very light 

 porous silicious spongy cup-shaped axis, the upper surface of which 

 is furnished with groups of small cylindrical pores placed in roses, 

 and with grooves radiating between each group of pores ; the lower 

 surface uniformly porous. 



MacAndrewia azorica. (PI. XV.) 



Hab. St. Michael's, Azores, 1851 {Robert MacAndreiv, Esq., 

 F.R.S., #•<?.). 



This sponge ? has so much the general appearance and habit of a 

 zoophyte with pinnated tentacles like the Alcyonium to which I 

 have referred above, that I am as yet by no means certain that it may 

 not be the product of such animals ; but I have not been able to 

 find any traces of the remains of them, and therefore must wait the 



