MADREPOEAEIAIS" SUBrAMILT LOPHOSEEINiE. 307 



Below the granulations, and on the sides of the septa for a short 

 distance down the interloculus, are some distinct small conical 

 granules ; and still lower down are the highest synapticula, which 

 nearly close in the loculus. 



A section or a fracture of the coral breaks the synapticula 

 across, and reveals the structures of the septa. These are trahe- 

 culate, especially near their free edges, are moderately stout, 

 and consist of vertical or slightly inclined processes swollen out 

 at regular intervals, and uniting at their sides within and without, 

 in the proper position of the coral in relation to the calicular 

 centre, with those next to them, by the same kind of structure. 

 As there is some symmetry in the succession of swellings and 

 constrictions of the series of trabeculse, there are more or less 

 regular, oval or circular foramina in vertical rows in the sides of 

 the trabeculate septa. This fenestration diminishes low down, and 

 is often replaced by parts of synapticula. 



Each warty granulation on the free side of a sej^tum is analo- 

 gous to the swelling of a trabecule ; and were its sides (distal 

 and proximal to the calicular centre) to unite, the union would 

 represent the process which unites the trabeculse lower down, 

 and the involved and included spaces would mimic the fenestra- 

 tion. During the growth of the coral this union takes place ; 

 and each of the successive nodules of a trabecula was once a warty 

 granulation at the free surface of the sept am. 



The sides of the nodules and intervening thinner parts are 

 ornamented here and there, and especially near to the calicular 

 centre, with distinct granules. Amongst these, and covering 

 more space, are small synapticula, circular more or less in frac- 

 tured outline, sometimes elongate, but low (in vertical measure- 

 ment), extending over more than one nodule and internodular 

 process, and also lumpy irregular synapticula covering much of 

 the septal surface low down, occluding fenestrations, and occu- 

 pying much of the loculus. 



The synapticula, varying greatly in their shape, occur be- 

 tween the septo-costge of the collines, and usually the long kind 

 predominate elsewhere, except low down, where the shape is very 

 irregular. The absence of synapticula on the septal surfaces 

 close to the calicular fossa is evident. There are no walls to the 

 calices or collines. 



Sections across the line of the septa and septo-costee show the 

 irregular dimensions of the synapticula and the spaces they close 



