Verrill, Kates on Madiata. 497 



The branchiform organs are dark greenish, broad, short, strongly 

 arched. 



Panama, — LeConte ; Pearl Islands, — F. H. Bradley. 



Mammillifera nitida Verriii. 



Poly])s close together on a broad basal membrane, rather tall, sub- 

 cylindrical, with a smooth soft surface ; height, of preserved specimens, 

 •30 to -40 ; diameter -12 to -15 of an inch. Tentacles, in the specimen 

 dissected, 54, rather long, slender, pointed. Color, in alcohol, dark 

 greenish. 



Acajutla, San Salvador, — F. II. Bradley. 



The slenderness and length of the tentacles will distinguish this 

 species from the preceding. 



Mammillifera conferta Verriii, sp. nov. 



Polyps so closely crowded upon the basal membrane that they are 

 usually in contact and pressed into polygonal forms. Column in con- 

 traction, low, rounded, mammilliform, about as broad as high. Sur- 

 face smooth, showing the internal lamellse through the walls. Tenta- 

 cles, in the specimens dissected, about 54, very short, like small, rounded 

 papillie, arranged in two regular series. Color, in alcohol, nearly 

 white. Height, in contraction, "08 to '12 ; diameter "10 to '12 of an 

 inch. 



San Salvador, — Capt. J. M. Dow ; Acapulco, — A. Agassiz. 



This species covers the surface of shells, etc., with its crowded 

 polyps, which are usually so close together as to entirely conceal the 

 basal membrane. 



EpizoanthuS G-ray (sens. mod.). (Gejimaria, 1st Ed.). 

 Gemmaria Duch. and M., Corall. des Antilles, p. 55, I860 (non McCrady). 

 Palythoa (pars) Edw. and H., Corall., i, p. 301, 1857. 

 Epizoanthus and Gemmaria Gr ly, Proc. Zool. Soc. London, 1867, p. 2.'57. 



Polyps arising from a broad, thin, basal membrane, sometimes cov- 

 ering dead shells occupied by hermit-crabs. Cohunn more or less ele- 

 vated ; surface indurated by a layer of firmly adherent grains of sand. 



EpizoanthllS elongatUS Verrill. (Gemmaria elongata, 1st Ed.). 



Basal membrane thin, encrusting rocks. Polyps very unequal in 

 size and height, mostly elongated, not crowded, separated usually by 

 distances less than the diameter of base. Column tall, sub-cylindrical, 

 often constricted somewhat at base, transversely wrinkled, the surface 

 covered throughout by a nearly uniform layer of small grains of sand. 

 Tentacles, in specimens dissected, numerous, about 4G, in two rows, 



