TRIBE III. MADREPORACEA. 507 



minute, with the interstices tuberculate; tubercles echinate, promi- 

 nent, columniform, sometimes confluent in ridges. 



A specimen allied to this species, yet possibly distinct, was obtained 

 at the Feejee Islands, and is represented on plate 47, figure 2. It is 

 a glomerate mass covered with large rounded tubercles (two to three 

 lines broad), some oblong and curving, and others nearly hemisphe- 

 rical. The cells are one-third of a line broad, and have a distinct star 

 of six rays, with the six intermediate usually apparent. One specimen 

 is three inches by four in breadth, and two to three thick. Figure 

 2 a represents the unexpanded animal ; 2 b, the interior structure in 

 a cross section, magnified twelve times. 



Porites tuberculosa, Lamarck, ii. 439, No. 13. 



26. MANOPORA PLANIUSCULA. (Dana.) 



M. glamerata, incntstans, superne planiuscula ; interstitiis 1-1 J'" latis, 

 paulum convexis. Corallum porosum ; cellis prof undis, viz conspicue 

 12-radiatis. 



Glomerate, incrusting, nearly plane above; interstices 1 to l lines 

 .broad, a little convex. Corallum porous; cells deep, rather in- 

 distinctly 12-rayed. 



Plate 47, fig. 3, corallum, natural size; 3 a, vertical section, en- 

 larged. 



Feejee Islands. Exp. Exp. 



An incrusting species nearly one-third of an inch thick, distin- 

 guished by the naked arid slightly convex interstices between the 

 cells, seldom exceeding half a line in height. The cells are large and 

 rather deeply seated. 



V. Cellis comlli in f undo favearum prof undarum immersis, interstitiis angustis, nudis. 



27. MANOPORA FOVEOLATA. (Dana.} 

 M. glomerata, incrustans, superne planiuscula, out undulata. Corallum 



