from the South' Australian Tertiaries, 



167 



without epitheca. The species P. alveolus (nobis), from the 

 West-Indian Miocene, is unique. 



The first species of the genus were described by MM. Milne- 

 Edwards and Jules Haime* — the P. lavis of the Philippines 

 and P. Candeanus of the Chinese seas. The next species were 

 described in my Essay on the Fossil Corals of the West-Indian 

 Islands t. The P. Lonsdalei resembles the Flabellum avicula in 

 many respects ; but the P. alveolus is unlike any other species 

 in its general shape. Lately some fossils from the Jamaica 

 Miocene have been described by me; but they are not yet pub- 

 lished : amongst them are P. costatus and the Flabellum which 

 is mimetic — the Flabellum exaratum, Dune. MSS. The group 

 then stands as follows, with its mimetic Flabella : — 



Pedicellate Flabella. 



Flabellum avicula, Mich., sp. 



Siciliense, E. ^ H. 



cuneiforme, Lonsdale. 



Truncate Flabella. 



Flabellum compressum,£amA:.,sp. 

 crenulatum, £. ^ H. 



Flabellum without epitheca. 

 Flabellum exaratum, n. sp. 



Pedicellate Placotrochi. 



Placotrochus Lonsdalei, Dune. 



deltoideus, n. sp. 



elongatus, n. sp. 



Truncate Placotrochi. 



Placotrochus Candeanus, E. ^ H. 

 leevis, E. ^- II. 



Placotrochus without epitheca. 

 Placotrochus costatus, n. sp. 



Anomalous. 

 Placotrochus alveolus, Dune. 



The truncate Flabella are all recent, except in the instance 

 now noticed ; and, until the discovery of Placotrochus Candeanus 

 in the iMuddy Creek, the truncate Placotrochi were the recent 

 forms : all the others belong to the Miocene age. There is no 

 more than a generic relation between the West-Indian and the 

 Australian Tertiary Placotrochi. 



The new BalanophijUia has only a generic affinity with B. 

 Cumingii, E. & H., of the Philippines, and is more closely allied 

 to the B.pralonga, Michel., sp., of the Turin Miocene : it belongs 

 to the same section of the genus as the Italian form, and they 

 have several peculiarities in common. The new species is no- 

 thing like our Crag species. 



The Trochoseris Ji'oodsi has only a generic affinity with the 

 T. Stokesi, E. & H., from the Philippines, and is very distinct 

 from the Eocene forms. 



Cellejiora Gambierensis, Busk, is a characteristic fossil of the 

 Mount-Gambier Tertiaries. 



♦ Hist. Nat. dcs Corall. vol. ii. p. 98. 

 t Quart. Jouru. Geol. Soc. vol. xix. 



