TERTIARY CORALS. 61 



Its septa are delicate, unequal, thin, and belong to four cycles, there being six systems. 

 The primary are the longest, and there are small pali before all except the septa of the 

 fourth and fifth orders. 



The columella is small, blunt, and delicately papillose. 



There are no costae. 



Height of corallum ^th — ^.ths inch. Diameter of calice j^th — ^ths inch. 



Locality. Ballad's Lane, Pinchley (London Clay). In the collection of N. T. 

 Wetherell, Esq., F.G.S. 



This species is closely allied to 0. conferta and 0. incrustans, and but remotely to 

 0. Halensis} The gemmation, the small columella and pali, and the septal arrange- 

 ment, distinguish the new species. 



^^CTioii—MADBEPOBABIA PERFORATA. 

 Family— MADREPORIDiE. 



Sub-family — Eupsammin.^. 

 Genus — Dendrophyllia. 

 Dendrophyllia elegans, Duncan. Plate X, figs. 15 — 19. 



The corallum has a broad encrusting base which gradually tapers into a tall, slender, 

 and straight stem, terminated by a calice. Gemmation occiurs close below the calicular 

 margin on the outside wall, and the branches are in whorls, are long, and do not coalesce. 



The calices are either circular in outline or compressed ; they are deep, have a very 

 irregular cellular margin, and a very regular septal arrangement ; they vary in size, and 

 are peculiarised by long, thin, and delicate septa, and large interseptal loculi. 



There are six systems of septa, and four complete cycles ; all the septa are well deve- 

 loped, laminar, and project very decidedly from the wall. The primary and secondary are 

 straight and project well inwards ; and processes from them develop the columella. The 

 tertiary septa are small, but well produced ; and the septa of the fourth and fifth orders 

 meet externally to the tertiary septa and proceed to the columella. The laminee are 

 sharply granular, but not irregularly so, and their perforations are decided. 



The columella is formed by processes from the ends of the septa, and is small. 



The costse are close, rounded above, and wider and more flattened below. The tipper 



1 Fossil Corals from Sinde : 'Ann. and Mag. Nat. Hist.,' April, 1864. 



