TRIBE III. MADREPORACEA. 513 



of this species, supposed to have been obtained at the Sandwich 

 Islands. They have an inverted pyriform shape (plate 48, fig. 4), 

 having been attached by the smaller end, are about two and a half 

 inches high, and alive for one and a half inches. In the size of the 

 cells and internal texture, they agree with the figure by Savigny. 

 Below the live part, the surface is covered with an incrusting Nul- 

 lipore, which advances upward as the animal dies. 



Mad. dedalca, Forskal, Anitn. Egyp., 133, Alcyonella SavigHii, Audouin, Explic. des 



tab. 37, fig. B ; the animal of this species planches de M. Savigny. 



was first imperfectly figured by Forskal. Forties dedalea, Ehrenb., G. Ixx., sp. 10. 



Madrepora, Savigny, PEgypte Pol., tab. Alvcopora dedalea, Blainv., Man., 394. 

 3, fig. 4. 



3. ALVEOPORA SPONGIOSA. (Dana.} 



A. grandis, lobato-glomerata, 10-12" animata. Corallum tenerius spon- 

 giosum; cellis ttnearibus, vix profun dis, apice valde miriaribus ; intus 

 JiUferis ; parietibus tenuissime cribratis, porulis angusto-oblongis. 



Large, lobato-glomerate, alive for 10 to 12 inches. Corallum spongy 

 and very tender ; cells a line in diameter, scarcely as deep as broad, 

 filiferous within; at apex much smaller; parietes filamento-cribrate, 

 porules narrow-oblong. 



Plate 48, fig. 3, corallum, reduced two diameters; 3 a, part of same, 

 natural size ; 3 b, cells of surface, enlarged ; 3 c, vertical section of a 

 cell; 3 d, vertical section of corallum, enlarged. 



Feejee Islands. Exp. Exp. 



The specimen in the collections is a large sponge-like mass, four- 

 teen inches high and six thick, with short rounded lobes above, and 

 alive throughout, excepting three inches below. The oblong porules 

 of the parietes are separated by thread-like intervals. 



4. ALVEOPORA RUBRA. (Quay 4- Gaymard.) 



A. furcato-ramosa, ramulis elongatis, erectis ; polypis rubris, breviter 

 crasso-tentaculatis. Corallum cellis spinosis, sex-dentatis. 



129 



