SERIATOPORA. POLYPI. 429 



branches tortuous, coalescing ; stars scattered, some immersed,, 

 others prominent, formed by lamellae. Inhabits Indian and Me- 

 diterranean seas Ellis, Zooph. pi. 36. 



O. prolifera, Lam. Branched, subdichotomous ; stars turbinated ; 

 margin proliferous. Norwegian Sea Ellis, Zooph. pi. 32, fig. 2. 



Gen. 14. SERIATOPORA, Lam. Madrepora, Pall. 

 Fixed, stony, branching; branches slender, subcylindrical; cells 

 perforated, lamellar, as if ciliated on the margin, and dis- 

 posed laterally in transverse or longitudinal series. 



S. subulaia, Lam. (M. seriata, Pall.) Much branched, diffuse ; 

 branches slender, subulate ; stars in a longitudinal series, with a 

 prominent and ciliated margin. Ellis, Zooph. pi. 31, fig. 1, 2. 



Gen. 15. MADREPORA, Lam. Lin. 



Fixed, subdendroidal, branching, the surface furnished on all 

 sides with projecting cells ; interstices porous ; cells scattered, 

 distinct, cylindrical, tubular, scarcely stelliferous, projecting ; 

 laminae very narrow. 



M. palmata, Lam. Broad, flattened, base convolute, deeply divid- 

 ed, muricated on both sides ; branches palmated or deeply cleft. 

 Inhabits American seas Sloane, Hist. Jam. i. pi. 17, fig. 3. 



M. corymbosa, Lam. Much branched, orbicular ; branches ascend- 

 ing ; ramuli many, spread out in a broad and oblique corymb ; 

 tubular cells unequal, crowded, and striated without. Inhabits 

 Indian Ocean. Rumph. Amb. pi. 86, fig. 2. 



Gen. 16. POCILLOPORA, Lam. 



Fixed, stony, branched or lobed, the surface furnished on all 

 sides with hollow cells with the interstices porous ; cells scat- 

 tered, distinct, the margin rarely projecting, and the stellse 

 scarcely apparent. 



P. acuta, Lam. (Madrepora damicornis, Soland.) Much branch- 

 ed ; branches divided, slender ; ramuli acute ; stellae crowded, 

 hollow, obsoletely lamellated. Indian Ocean. Ellis, Zooph. 170. 



Gen. 17. PORITES, Lam. Madrepora, Soland. 

 Fixed, stony, branched or lobed and obtuse; surface stelliferous; 

 stelloe regular, sub-contiguous, superficial or excavated, the 

 margins imperfect or none ; filamentous laminae sharp or 

 pointed. 



This genus, though varying in general form, is to be distinguished by their dicho- 

 tomous and obtuse lobes, sometimes slightly compressed on the sides, and by the 

 stellae being superficial, more or less contiguous, and imperfectly or not circumscribed. 

 It is numerous in species. 



P. clavaria, Lin. (M. porites, Lin.) Dichotomously branched ; 

 ramuli thick, subclavate, obsoletely compressed; stellae broad, flat- 

 tish, contiguous, superficial. Inhabits American and Indian seas. 

 Ellis, Zooph. pi. 47, fig. 1. 



