208 



Descriptions of New Species of Corals 

 FROM THE Australian Tertiaries. 



By J. Dennant, F.G.S. 



[Read September 8, 1903.] 



PART VI. 



Plates I. and II. 



Tpochocyathus Maplestonei, spec. nov. PL i., figs, la, 6. 



Tlie corallum is cuneiform and compressed from the calice 

 downwards to the base, which is rounded and usually some^ 

 what flattened inferiorly. Examples also occur with an 

 almost pointed base. Amongst the smaller specimens some 

 resemble the type in shape, while others are shoii) squat forms 

 with a flat base. The corals are free, but in one or two 

 examples there is evidently a scar of former attachment. Th& 

 calice is shallow, widely open, and elliptical ; the ratio of the 

 major and minor axes varies from 100 to 84, as in the type, 

 to 100 to 91 in on© of the short squat forms mentioned. 



The septa are in six systems, with three cycles. The first 

 and second orders are equal in thickness, and much stouter 

 inferiorly than at their upper margins ; the primaries also are 

 slightly longer than the secondaries. The tertiaries are 

 shorter and much thinner. All are exsert and granulose on 

 their sides. 



The columella is fascicular, and consists of one or more irreg- 

 ular processes. The pali are in two crowns, and are placed 

 before the primary and secondary septa. In the figui^ed 

 example (the type) they have an in-egular outline, which is 

 partly at least due to wearing ; a young individual shows fairly 

 regular pali. They join the two first orders of septa, and also 

 the columella, by short rod-like lateral processes. Below th& 

 prominent columella and pali there is in the type apparent 

 solid matter, but this is no doubt due to secondary infilling,, 

 since in a small fractured example the central axis has a 

 trabecular appearance. Most of my specimens have the calice 

 more or less choked, and I have relied upon three only, includ- 

 ing that figured, for my reading of the calicular structure. 



The wall is stout and covered by a delicate epitheca, through 

 which the costse are visible from the summit of the coraJl down 

 to the base. There are four orders of costae, the first three 



