2o8 TABULATE CORALS. 



quite obsolete. Tabulae well developed, usually more or less 

 regularly funnel-shaped, and often giving rise to a more or less 

 continuous tube occupying the axis of the visceral chamber. 

 Septa usually slightly developed, spiniform, never lamellar. 



Obs. — Few genera of Palaeozoic corals are more clearly 

 marked out than Syj^ingopora by the general form and mode 

 of ofrowth of the corallum. The corallum commences as a 

 stoloniferous prostrate network of anastomosing tubes, which 

 closely resemble an Aulopora In general appearance, and have 

 given rise to the opinion that Aulopora is founded simply upon 

 young colonies of Syinngopora. The chief grounds for rejecting 

 this view will be briefly discussed hereafter, but there is one 

 consideration to which attention may here be drawn. The 

 prostrate network which forms the base of a colony of Syringo- 

 pora can be admirably studied in forms like S. fascictilaris, 

 Linn., of the Upper Silurian ; and in these cases we find that 

 there is presented to our observation the binder siwface of the 

 basal reticulation, as figured by Edwards and Haime in the 

 British Fossil Corals, PI. LXV., fig. i c. Now this under 

 surface of the network would, if the coral were an Attlopoi^a, 

 be cemented firmly to some foreign object throughout the 

 whole of its extent, and It would not therefore be exposed to 

 view at all. On the other hand, there is the clearest possible 

 evidence that the basal reticulation of Syringopora was not 

 parasitic at all, and that its under surface was quite free as a 

 general rule, except at one or more circumscribed points of 

 attachment. Whether or not the tipper surface of the basal 

 reticulation of a Syringopora, prior to the formation of the 

 ascending corallitcs, has ever been so much as actually observed, 

 Is a matter quite open to question. Cases In which the upper 

 surface of such a reticulation have been described or figured 

 {e.g., by Edwards and Haime, Brit. Foss. Cor., PI. LXV., fig. i) 

 may admit of the explanation that the observer was in reality 

 dealing with the colony of a true Aulopora. It seems, indeed, 

 in the highest degree probable that the formation of the ver- 

 tically ascending corallites is commenced in the very earliest 



