TRIBE III. M ADREPORACEA. 517 



Porites elongata, Lamk., ii. 437, No. 7. Sideropora ehngata, Blainville, Man., 384. 

 , Deslongchamps, Encyc., 652. 



NOTE. S. pistillata. Esper's Madrepora pistittata (the Stylophora of Schweigger, 

 p. 413), is, beyond doubt, a Sideropora, and possibly a variety of this species. Pflanz. 

 Fortsetz. i. 73, tab. 60. 



Ehrenberg, placing the species with his Porites, as Porites pistillata, gives the follow- 

 ing description of a specimen from the Red Sea, which he considers identical with it (G. 

 Ixx., sp. 3): " Ramulis teretibus, gracilibus, flexuosis, apice rotundatis (4'" crassis) ad 

 dichotomiam incrassatis, ste"llulis sexangularibus, columella inclusa pistillatis, denticulo 

 hispido, supero obsolete fornicatis, interstitiis setuloso-hispidis, planis." 



3. SIDEROPORA SUBDIGITATA. (Lamarck.} Blainville. 



S. lobato-ramulosa, ramis brevibus, subdigitatis. Corallum stettis sex- 

 dentatis ; interstitiis prominulis et echinulatis. 



Lobato-ramulose ; branches short, subdigitate. Corallum with the 

 stars sex-dentate; interstices a little prominent and echinulate. 



The Indian or Austral Ocean. Lamarck. 



Porites snbdigitata, Lamk., ii. 438, No. 10. Sideropora subdigitata, Blainv. Man., 384. 

 , Deslongchamps, Encycl., 653. 



4. SIDEROPORA PALMATA. (Blainville.) 



S. ramis valde compressis et superne rarioribus,flabellatis,parce digitato- 

 lobatis aut subpalmatis, sape 1-2" latis, et apice 3-5'" crassis. Co- 

 rallum cellis paulum marginatis, columella prominula. 



Branches much compressed and thinner above, flabellate, sparingly 

 digitate lobed, or subpalmate, often 1 to 2 inches broad, and 3 to 5 

 lines thick at apex. Corallum having the cells slightly margined, 

 and the columella a little prominent. 



East Indies. Exp. Exp. 



The clumps in the Expedition collections, which have afforded this 

 description, are flattened hemispherical, about six inches high, and ten 

 or twelve broad, and consist of flat branches thinning towards the 

 apex. This last character and the less distinctly vaulted cells distin- 



130 



