RECENT CORALS FROM THE SOUTH AUSTRALIAN AND 
VICTORIAN COASTS. 
By Јонх DENNANT, F.G.S. 
[Read April 7, 1904.] 
Prates, I. AND II. 
About three years ago I was requested by Dr. Verco to 
determine the corals from his dredgings in St. Vincent and 
Spencer Gulfs. The material forwarded to me comprised also 
numerous polyzoa and echinoderms. The former I handed to 
Mr. C. M. Maplestone, who has already described several new 
species contained in the dredgings. The echinoderms have been 
placed in the hands of a specialist, and will, I trust, be dealt 
with shortly. The present communication treats of the corals in 
Dr. Verco's collection, together with a restricted Victorian 
species handed to me by Mr. Mulder. Several of the South 
Australian corals occur also in Victorian waters. 
Of the eleven species to be considered, six are new, and the 
remaining five have been previously figured and described by 
various authors. 
The occurrence of a recent species of Tenison Woods' tertiary 
genus Trematotrochus is of especial interest, as it emphasises the 
close relationship which exists between the living fauna of the 
Australian seas and the earlier one disclosed by the fossils of the 
tertiary period. This genus is purely Australian, and includes 
species in which the wall is actually perforate, together with 
others where the intercostal spaces, though fenestrated in the 
same manner, have the internal theca entire. Such being the 
case, the broad distinction usually made between perforate and 
non-perforate corals breaks down. The wall of a perforate 
Trematotrochus is analogous to the base of Stephanocyathus, but 
its calice is Turbinolian in character. The imperforate species of 
the genus have similar calices, and externally a precisely similar 
wall. 
Another Australian genus, Holcotrochus, is represented in the 
collection by two species, one of which is also recorded from the 
Muddy Creek tertiaries. 
The genus Platytrochus was long supposed to be restricted to 
the Eocene of Alabama; but it is now recognised as both 
tertiary and recent in Australia, one species being common to 
the two horizons. Duncan, in his “Revision of the Madre- 
poraria," mentions with a query the Australian seas as a locality 
for the genus; but on what authority I have been unable to 
ascertain. "Vaughan copies Duncan's remark, though on another 
page he states that Platytrochus is an extinct genus.* 
- * Coral Fauna of the United States. Washington, 1900. 
A 
