18 



another example from Wirrialpa (PI. III., fig. 8) consisting of the 

 inner ends of a few septa, there is also visible the inner perfor- 

 ated wall plate precisely similar to the parallel structure of C. 

 2Kindora, Bornemann,* and C. anthemis ? Bornemann.f Some 

 portion of this tissue is also perceptible on the side of the end, or 

 last septum, as a pellicle-like lining. 



Identical characters can likewise be detected in a more perfect 

 example in the richly-coloured Ardrossan limestone (PL III., fig. 

 3). This figure represents a partially oblique fractured section 

 from the base upwards, cutting the interseptal tissue at more 

 than one angle, and it further illustrates the dense nature of the 

 corallum substance. On the upper side this specimen measures 

 one and three-quarter inches by one and a quarter inches, the 

 septal area varying from one to two-eighths of an inch in width. 

 The inner perforated lamina, or wall-plate, is also visible (PL III,, 

 figs. 2, 4, and 8). To this fossil I purpose applying the name of 

 Coscinocyathus Tatei, in honour of Prof. Ralph Tate, F.L.S., of 

 Adelaide University, to whose kindness I am indebted for an 

 opportunity of describing these interesting fossils. 



Genus Protopharetra. 



This name was applied by Dr. Bornemannj to bodies from the 

 Sardinian limestones, regarded by him as the "lower or vegeta- 

 tive state of development of forms of ArchcEOcyathus and Coscino- 

 cyathus.'" Dr. Hinde, on the other hand, is not satisfied " that 

 these fossils are merely the lower state of development of Archceo- 

 cyathus forms," as very small specimens of both Protopharetra 

 and Archceocyatlius are present in the same hand specimens. 



A detailed diagnosis of this genus has not been given by 

 Bornemann, but Hinde describes it thus : — " It includes bodies 

 of very varying forms, either cylindrical or growing in extended 

 masses, from which simple or furiated stems are given ofi*. The 

 stems have a tube-like, axial cavity, crossed by tabulie 

 and bounded by the porous walls. These consist of a delicate, 

 fibrous, calcareous tissue, of dull, nearly opaque, milk-white 

 aspect in thin sections. The fibres may be cylindrical or flat- 

 tened, and they anastomose with each other . . . ." 



The forms now referred to Protopharetra occur but sparingly 

 .at Kanyka, associated with Ethmophylliim Hindei, as round or 

 •oval, more or less cylindrical bodies, possessing a central cavity, 

 surrounded by a zone of rather dense vermicular tissue, and when 

 viewed with a low power closely resemble Bornemann's figures of 

 P. densa% and P. radiata.\\ The tubular cavity occupies but a 



* Loc. cit., t. 25, f. 2. %Loc. cif., t. 8, f. 6 and 7. 



ilbid, t. 24, f. 5. li Ihid, t. 7, f. 1 aud 2. 



XLoc. cit., p. 46. 



