TRIBE III. MADREPORACEA. 477 



50. MADREPORA DIVARICATA. (Dana.} 



M. fruticose arborescens, late valdeque ramosa, paulum prolifera, ramis 

 divaricatis, arcuatis, subteretibus, |" crassis, ramulis extremis attenu- 

 atis, 4-6'" crassis. Corattum leve ; caliculo apicali crasso (!'"), ex- 

 serto; later alibus remotis, validissimis, divaricatis, vix striatis, plerum- 

 que ekngato-tubiformibus ('2'"), paucis gran dioribus proliferis ; multis 

 brevibus et orbiculato-nariformibus ; stella inter dum conspicud, duabus 

 lamellis prominulioribus. 



Shrubby arborescent, much and spreading ramose, a little proliferous; 

 branches divaricate, arcuate, subterete, of an inch thick ; branch- 

 lets attenuate. 4 to 6 lines thick. Corallum smooth; apical calicle 

 large (1| lines broad), exsert; the lateral remote, divaricate, very 

 stout, scarcely striate, some long-tubiforrn (2 lines long), a few 

 larger and proliferous, many short and round-nariform ; star some- 

 times distinct, with two of the lamellae most prominent. 



Plate 41, fig. 2, part of corallum, natural size; 2 a, extremity of 

 branch. 



Feejee Islands. Exp. Exp. 



The specimen of this species in the collections is a much-branched 

 clump, about eight inches high and ten broad, remarkable for the re- 

 moteness, inequality, and stoutness of its calicles, which give the 

 branches an uneven appearance. The larger tubiform calicles are 

 from a line to a line and a half in diameter, and are placed nearly at 

 right angles with the branch. The cells are all very large; those in 

 the smaller obsolescent calicles are about two-thirds of a line broad, 

 and contain a distinct star of six rays. The surface of the calicles is 

 scarcely striate, though harsh to the feel. 



51. MADREPORA ABROTANOIDES. (Lamarck.} 



M. fruticosa, late ramosa, ramis vix teretibus, -" crassis, ramulis 

 extremis 3-4'" crassis, arcuatis et pyramidato-attenuatis, valde brevi- 

 terque proliferis. Corallum subleve, caliculo apicali 1"' lato, exserto ; 

 lateralibus confertis, compresso-tubiformibus et tubo-nariformibus ; 



120 



