101 



very abundant exotheea. Calices circular ; septa in four cycles, 

 three of which are of equal length. There are no calices 

 sufficiently perfect to show the pali ; but in section the septa 

 are all much thickened close to the columella, which seems to 

 have been compact. Endotheca very abundant, curved up- 

 wards from the columella, and showing eight or ten transverse 

 partitions to each of the loculi. Costce continuous with the 

 septa, those belonging to the first cycle being very long, and 

 showing no break at the wall, but passing through it into the 

 septa. Sometimes, though rarely, the costse are confluent with 

 the costee of the neighbouring calice, but in this case there is 

 always a thin lamina of epitheca, which forms in section a 

 secondary wall. The internal edges of the septa appear to 

 have been dentate. The endotheca and exotheea are about 

 equally abundant, and the fourth cycle of septa is rudimentary 

 in some of the systems, and very small in all. 



Diameter of calices, seven to eight millimetres. 



I have already described one fossil species of Flesiastrcea, 

 P. St. Vincenti (Trans. Phil. Soc., Adelaide, 1878, p. 116), but 

 it is much smaller than this species. The genus may be said to 

 be almost an Australian one, arid the discovery of two fossil 

 species entitle it still more to this character. The present 

 species is quite tropical in aspect, and would form reefs. It is 

 unusually hard and compact in texture, and, like the fossil 

 previously described, it is very ferruginous, which is not the 

 case with P. St. Vincenti. The details are not very satisfac- 

 torily seen, but other specimens will doubtless be discovered in 

 the course of time. 



Microtrochus minutus, spec. nov. ; PI. iv., figs. 3a— 3b. 



The third species of coral here to be noticed is a minute 

 fossil adhering to the base of a Limulite from the Miocene beds 

 of Muddy Creek. It probably belongs to the second or epithe- 

 cated division of Trochosmiliacese, -but being in a young state 

 not anything very definite about its position can be stated,, 

 though I do not think it belongs to any described. 



Corallum minute, not a millimetre in height, attached by 

 one side to the base of Lunulites cupola, mihi ; rather higher 

 than broad. Side with six distinct costae, which are larger 

 towards the end. About half way up they are concealed by 

 concentric layers of rugose epitheca, through which the costal 

 are faintly visible. Calice nearly circular, uneven at the 

 edge. Septa twelve in number, undulating, sparsely spinous, 

 finely granular, with toothed uneven edges. Columella repre- 

 sented by three or four twisted processes, which are joined to 

 the septa. Endotheca doubtful, but apparently existing 

 between some of the lower septa. 



