2 72 TABULATE CORALS. 



impossible, therefore, that it is upon some such specimen as 

 the preceding that M'Coy founded the statement that I have 

 referred to. 



As regards the later history of Monticiilipora, it is sufficient 

 to add here that Milne-Edwards and Haime at first placed all 

 the forms referred to this genus under Cho'tctcs (Pol. Foss. des 

 Terr. Pal, p. 261, 185 1), but that they subsequently accepted 

 the genus as distinct (Brit. Foss. Cor., p. 264, 1854). In this 

 course — whatever differences of opinion as to the affinities of 

 the genus may have been expressed — Milne-Edwards and 

 Haime have been followed by almost all paleeontologists. For 

 my own part, as previously mentioned in speaking of Chcetetcs, 

 I have been disposed to consider that no sufficient characters 

 had been indicated whereby Monticidipora, D'Orb., could be 

 separated generically from ChcEtdes, Fischer ; and I have de- 

 scribed a number of species of the former genus under the 

 latter title. Having now, however, had the opportunity of 

 examining authentic specimens of the type-species of Chcetetcs 

 (the C. 7'adiaiis, Fischer, of Russia), I am quite satisfied as to 

 the complete distinctness of this genus, and, consequently, as 

 to the necessity for retaining the genus Montictdipora. 



The genus Monticulipora — using this term in the meanwhile 

 in a wide general sense — includes Palaeozoic coralla of the most 

 variable form. In many cases the corallum is massive, con- 

 sisting of a variably-shaped aggregation of diverging corallites 

 based upon an inferior epitheca, and having the calices placed 

 exclusively upon the upper surface. In other cases, including, 

 perhaps, the majority of species, the corallum is ramose, or 

 dendroid, fixed by its base, and having the calices opening over 

 the whole of the free surface. In another group the corallum 

 is fixed by its base, but has the form of a flattened, palmate, 

 and variously-divided frond, the corallites diverging from the 

 imaginary median plane of the expansion and opening on the 

 two flat surfaces. In still another group, the corallum forms 

 a thin crust, growing parasitically upon foreign bodies ; but 

 though some undoubted species of the genus have this habit, it 



