DESCRIPTIVE PART. 



MADEEPORA. 



Millepora (part.), Linnseus, Sj-st. Nat. ed. x. p. 790. 



Madreporce anomalce (part.), Pallas, Eleiichus Zoophytorum, p. 279. 



Madrepora (part.), Linnaeus, Sj-st. Nat. ed. xii. p. 1272 ; Esper, Pflanzenth. i. p. 61 ; EUis & Solander, 



Zoophytes, p. 145 ; Lamarck, Syst. Anim. sans Vert. 1801, p. 371. 

 Madrepora, Lamarck, Anim. sans Vert. 1810, t. ii. p. 277 (pro parte). 

 ? Porites (part.), Ehrenberp:, Corallenth. d. roth. Meeres, p. 113 : Lamarck, op. cit. p. 267. 

 Asira>a (part.), Lamarck, op. cit. p. 257. 

 Oculina (part.), Lamarck, op. cit. p. 283. 



Heieropora, Ehrenberp; (iion Blainville), Corallenth. d. roth. Meeres, p. 106. 

 Madrepora, Dana, M.-Edwards & Haime, and all subsequent authors 



Definition. — Perforate Madreporaria in which independent colony-formation takes place 

 by means of indirect budding around the wall of an axial corallite, which, by increase in 

 dimensions, becomes a branch. Further subdivision takes place when any of the radial 

 corallites, produced as buds, assume the characters of an axial corallite. A prominent 

 corallite-wall is never entirely wanting, but may, in certain cases, be confined to those 

 corallites situated near the apex of a branch. The corallites are, in typical cases, provided 

 with 12 septa, arranged in two cycles of 6 each. In a few instances a third cycle of 12 

 septa may be present ; but such a condition is, so far as known, confined to certain corallites, 

 and is not common to the whole colony. On the other hand, in some species the second 

 cycle is not developed, and in other cases the septa of the radial corallites may be reduced 

 to two or even to one. A true columella is absent ; but in case the septa are well -developed, 

 two or more of the primary series may become confluent. Only one species is known in 

 which the septa are exsert, and in that case the feature is confined to immersed corallites. 

 The polyps are provided with 12 tentacles and 12 mesenteries (presumably with more in case 

 there are more than 12 septa). They exhibit a marked bilateral arrangement of parts, 

 which is frequently indicated in the corallites by the greater development of an outer and 

 often also of an inner septum, each of which corresponds with an extremity of the elongate 



B 



