11 



fossils and abundantly minute fragments of such, but the upper 

 one by far the most, conspicuous amongst which occasionally a 

 fcrilobite; and coral structure appears to perfection in sea-rolled 

 pebbles, the fossil shows in beautiful contrast of colour upon 

 the smooth surface. Prof. Tate holds the tentative opinion that 

 the fossils are of the Lower Silurian age of Murchison." At p. 48 

 of the same volume Prof. Tate states that " the fossils consist 

 chiefly of heads and other fragments of a species of blind trilobite, 

 probably an Olemis, a small species of ^uculiomphalus, a Capulus, 

 a Creseis?, and fragments of corals (some of which show a 

 cystiphylloid structure)." Below these beds Mr. Tepper describes 

 unconformable to them the " Ardrossan Marbles," a yellowish or 

 pink-coloured, but not variegated, saccharoid limestone of Pre- 

 Silurian ao-e. Tlie a^e and relation of these fossiliferous lime- 

 stones to foreign equivalents will be discussed later. 



The Family Archaeocyathinse of Bornemann consists of the 

 Genera Archoeocyathus, Billings, EtlwiojyhylJum, Meek, Coscino- 

 cyathus, Bornemann, Antliomorpha, Bornemann, Protoj^haretra, 

 Bornemann, and Spirocyathus, Hinde, according to the last- 

 named author. 



If certain determinations of the late Prof. L. Cr. de Koninck 

 are to be relied on the family is already known in the Devonian (?) 

 rocks of New South Wales. In 1876 he describes some ill-pre- 

 served fossils from the Yass district, provisionally called ArchcEO- 

 cyathus (?) Clarkei* They formed a portion of the late Rev, 

 W. B. Clarke's collection in the Mining and Geological Museum, 

 and were destroyed with the general body of that series in the 

 Garden Palace fire, and I regret to say we are not again in pos- 

 session of a specimen of this fossil. Its true affinities must for 

 the present, therefore, remain doubtful, for we find Dr. Hinde re- 

 marking — " Judging from the description and figures, no definite 

 opinion can be formed as to their real character." According to 

 DeKoninck A. (?) Clarkei consists of irregidarly-plicated bodies 

 of considerable extent, both laterally and longitudinally, enclos- 

 ing deep cavities of very variable form. The tissue forming the 

 walls is from eight to ten millimetres in thickness, the external 

 walls being furnished with irregular protuberances, and pierced 

 by small openings. The tissue between the walls is irregularly 

 spongy, and retiform in structure. 



So far as I am aware this is the only reference to the occur- 

 rence of a supposed Arclicpocyatlius^ or one of its allies, in Aus- 

 tralia, but quite recently Prof. W. J. Stephens, M.A., has oblig- 

 ingly lent me two specimens from the neighbourhood of Yass, 

 which may turn out to be of this nature. I may, however, state 



* Foss. Pal. Nouv. Galles du Sud, 1876, pt. 2, p. 68, t. 2, f. 1. 



