392 R. F. Tomes — Inferior Oolite Mad 'repar aria. 



Stephanoccenia dendroidea, sp. nov. (Plate X. Fig. 10.) 



I have long been familiar with fragments of a tall dendroid Coral 

 from the Oolite Marl of Leckhampton Hill, which had characters I 

 could not associate with any other Oolitic species, but which were 

 too ill-preserved for identification. Some well-preserved pieces of 

 a large specimen from Birdlip Hill, also from the Oolite Marl, having 

 lately come into my hands, I am now able to describe this species as 

 follows : — 



The corallum is tall and branching, and attains to a height of a 

 foot, or a foot and a half, and has very much the habit of growth of 

 Thamnastrcea LyeUi. The basal part has sometimes a diameter of as 

 much as two inches, the horizontal section of which, as well as that 

 of the branches, is nearly round, but they are nevertheless consider- 

 ably nodulated. 



The calices are evenly distributed, but are a little more distant 

 from each other in the longitudinal direction of the branches. They 

 are for the most part lozenge-shaped, ovoid, or even quadrangular ; 

 but the largest have a rounded outline, and there is a delicate but 

 distinct line of depression between them. They are superficial, but 

 have a circular and open centre. 



The septa are short and stout, and they are continuous with those 

 of adjoining calices, with which they unite, but yet are divided by 

 the fine but distinct line before mentioned. When the septa are 

 worn down, this line of depression is obliterated, and many of the 

 united septa are very regularly geniculated. In a full-sized calice 

 there are about thirty septa which are, generally speaking, of nearly 

 the same thickness and length. Those, however, which have pali 

 before them are a little stouter than the others. The pali are of 

 nearly equal thickness and length with the septa, and in a calice 

 having thirty septa there are fourteen pali, that is to say, nearly each 

 alternate septum has one before it. 



The columella is small and deeply seated. Itis styliform, though 

 a little compressed, and it is united in some of the calices to one of 

 the pali. Both septa and pali are regularly denticulated, and the 

 greater diameter of the denticulations is across the septum. This 

 is most distinctly observable towards the ends of the branches, 

 where the calices are circular and much more prominent. 



When the septa are worn smooth and the lines of junction with 

 those of contiguous calices are obliterated, this Coral has much the 

 aspect of a Thamnastrcea. Gemmation appears to take place in the 

 interval between the calices, where smaller calices are observable. 

 There is so much similarity between the septa of this species that I 

 am wholly unable to trace the cycles. The cycles of the pali for the 

 same reason are equally difficult of determination. The appearance 

 presented is that of a calice with fourteen principal septa, and their 

 pali. The diameter of the calices is about one line. 



Although the genus Stephanocoenia is placed in the Eusmelince, and 

 for want of better information respecting the Oolitic species I have 

 placed the present species in that family, I am by no means assured 

 that it should not be included in the Astrceince. That both septa 



