1870. } DUNCAN—AUSTRALIAN CORALS. 309 
China seas ; and the last is closely allied to such forms as the recent 
F. Stokesi and F. crassum ; but it has a fair specific distinction in the 
development of its septal cycles. Moreover F. Victoriw has the 
peculiar arrangement of the septo-costal structures mentioned in 
treating of the Sphenotrochi. 
Placotrochi are Flabella with an essential and lamellar columella ; 
and there are species mimetic of the divisions of the genus Flabellum. 
There are two recent species. One, P. Candeanus (China), has a 
pedicellate base, and is closely allied to Placotrochus elongatus from 
the Australian Tertiaries; and the other, P. levis, is truncate, and 
is not represented in the fossil state. Placotrochus deltoideus is a fine 
species, and is very characteristic of the Australian Tertiaries. 
The genus is not represented in any Kuropean formation; but it 
has four species in the Miocene of Jamaica and San Domingo. It 
has not been distinguished, as yet, amongst the results of the dredg- 
ings off Florida and Havanna. The West-Indian species are very 
distinct from the Australian, and have only a generic affinity with 
the Chinese recent forms. 
The interesting characters of Palawoseris Woodsi have already been 
noticed. The genus is allied to Turbinoseris, Duncan, from the 
Lower Greensand, but it has no tertiary or recent congeners. 
Cycloseris tenws is closely allied to Pungia tenms, Dana, which is 
probably a Cycloseris. The thin Cycloserides are well-known fossils 
in the nummulitic rocks of the 8. of France ; and there is one species 
in the Cenomanian. The recent species are from the Philippines and 
China. 
Amphihelia incrustans is closely allied to A. venusta of the Aus- 
tralian coast. The dwarfed and incrusting nature of the coral, and 
its excessively rare calices and great amount of intercalicular tissue, 
covered with cost, distinguish the fossil form from all the others of 
the genus. The Amphihelie range from the Miocene of Sicily to the 
recent deposits in the deep sea of the N.E. Atlantic, where the earliest 
species still exists. Recent investigations into the affinities of the 
Oculinide, which are not yet finished, lead me to expect that this Au- 
stralian fossil form is most closely allied to some from the Atlantic. 
The most interesting of the corals from the Cainozoic deposits of 
South Australia are the Conosmilie. It is a genus perfectly Aus- 
tralian in its abnormalities. A simple coral with a pellicular epi- 
theca, having a beautiful herring-bone ornamentation, with an essen- 
tial, twisted, ‘“sérialaire ” columella with endothecal dissepiments, 
and with plain septa, which have the hexameral arrangement in some 
and the octomeral in others, is a form containing the elements of 
several classificatory series. The irregular septal arrangement amongst 
the closely allied species may be considered to depend upon atavism. 
Such octomeral cyclical arrangements occurred in some genera in the 
Lower-Greensand period and during the Oolites. Some of the Liassic 
Montlivaltie clearly reflected this rugose peculiarity; and 1. Ruperti, 
Duncan, had a quaternary cyclical arrangement. It is remarkable 
that the septo-costal peculiarity already mentioned as occurring in the 
Australian Flabellum Victorice and in the two species of Sphenotro- 
