305 
Affinities. —This species is so close to the Middle Devonian form 
C mitchelli Eth. fil. 1 that it was at first sight identified with it. A 
microscopical examination of the Gippsland Silurian species showed it, 
however, to differ in the following characters :— 
Cyathophyllum approximans. 
Septa varying from 35 to 40, never more. Thickened in median 
area. 
Dissepiments thin and vesiculose. 
Epitheca thin. 
Corallite wall straight. 
Cyathophyllum m ite belli. 
Septa varying from 40 to 44. Uniform in thickness. 
Dissepiments thick and regularly curved. 
Epitheca thick. 
Corallite wall often flexuose. 
Observations This elegant species is not uncommon in the Silurian 
limestone of Cooper’s Creek, Gippsland. It occurs in the present series 
in No. 746. in which a weathered example measures 8.5cm. by 7cm. 
Some typical specimens of C. approximans are also found in a collection 
of fossils presented to the National Museum by the Rev. A. W. Cresswell, 
M.A., in 1887. from the same locality. A transverse section of one of 
these is here figured. 
In working out the affinities of this species I have been assisted by 
the kindness of Mr. A. J. Shoarsby, F.R.M.S., of Yass, who has supplied 
me with specimens of C. mitchelli from New South Wales for comparison, 
and who confirms my opinion as to the distinctness of the two forms. 
Genus Phillipsastraea Edwards & Haime. 
Phillipsastr^a walli Etheridge fil. Plate XLVIII., figs, 7-9. 
Phillipsastrcea walli It. Etheridge, jnr., 1892 ., Rec. Geol. Surv., N.S. Wales, vol. II., pt. 4 , p. 169 , 
pi. XI., fig. 7. 
As Mr. Etheridge has pointed out, this coral is related to certain species 
with delicate septa like P. bowerbanki Ed. & H. sp. It further agrees 
with that species in the approximate number of septa. By its occurrence 
with some frequency in the Silurian of Hatton’s Corner, near Yass, this 
coral establishes its position as an undoubted member of the Silurian fauna 
of S.E. Australia, although a Devonian genus elsetvhere; and this is fur¬ 
ther supported by its present occurrence at Loyola, near Mansfield, in a 
fauna typically Wenlockian. 
The specimens from the blue limestone of Loyola are excellently pre¬ 
served, and it appears to be a not infrequent fossil in that series. The 
mural circle of the calices is not so w r ell developed in the Victorian ex¬ 
amples, but the boundary can be distinguished by the change of form in 
the dissepiments from convex to concave as they pass beyond what might be 
termed the “primitive cup.’’ The Victorian specimens agree with Mr. 
Etheridge’s in having 20 septa, and so far as I have seen, the calices in 
ours are from 4-6mm. apart. 
P. walli occurs in quite large masses in the Loyola limestone, one frag¬ 
ment of a larger piece measuring as much as 15cm. by 7cm., and. nearly 
3cm. in thickness. 
1. Rec. Ged. Surv. N.S.Wales, vol. II., pt. 4, 1S92, p. 172, pi. XI., figs. 9, 10 ; pi. XII., fig. 4 
