TRIBE I. ASTRJ3ACEA. 171 



Corallum with the ridges sulcate, 5 to 6 lines wide; gyri sinuous, 

 6 to 7 lines broad, lamellae rounded, fossae 3 to 4 lines deep ; inferior 

 surface smooth, except within ^ of an inch of the margin, where it 

 is rugose and remotely striate. 



Plate 14, figure 13, outline of the lamellse and trench. 



West Indies. 



The sulcate (or duplicate) ridges of this species, in connexion with 

 the very broad gyri, distinguish it readily from the following. The 

 septum is a line thick at top, an eighth of an inch below, and is a 

 very little turgid. On the under surface, beyond a fourth of an inch 

 from the margin, the corallum is smooth and mostly incrusted by 

 other corals. 



Madrepora mceandrites, Ellis and Solander, Meandritia pectinata, Lamouroux, Exp. 



161, tab. 48, fig. 1. The figure agrees Meth. 55, tab. 48, fig. 1, and Encyc., pi. 



with specimens examined by the author, 485, fig. 1 . 



even to the linear lamella at the bottom , Blainville, Man. d'Actin., 357. 



of the trench. The Manicina pectinata of Ehrenberg (G. 



Madrepora labyrinthica, Pallas Elench. Ixiii. sp. 3) is represented according to 



Zooph., p. 297. this author by Seba's fig. 8, tab. Ill, 



Meandrina pectinata, Lamarck, 2d ed. ii. (vol. iii.), which is a species with thin 



387, No. 4. lamellse. See Mussafragilis. 



2. CTENOPHYLLIA QUADRATA. (Dana.) 



Corallum collibus scepius sulcatis, subquadratis, 3-4'" latis, gyris 45'" 

 latis,fossis 3'" profundis ; septo scepe 1'" crasso; superfaie inferiore, 

 ad J", rugatd et striata. 



Corallum usually with sulcate subquadrate ridges, 3 to 4 lines broad ; 

 gyri 4 to 5 lines broad, fossae 3 lines deep, septum often 1 line thick; 

 lower surface for ^ inch crimpled and striate. 



Plate 14, figure 14, outline of the lamellae and trenches. 



The gyri are much narrower than in the pectinata, and the lamellae 

 smaller, though still very stout. 



