166 Dr. P. M. Duncan on Fossil Corals and EcMnoderms 



The species is closely allied to H. Hoffmanni, Goldf. ; but it 

 has non-crenulate tubercles, which have a tendency to touch the 

 scrobicular circle. It is easily distinguished from the Javan 

 Tertiary species, and from the Hemipatagus Grignoniensis. 



11. Clypeaster folium, Agassiz. 



Var. with a marginal periproct. 



Locality. Muddy Creek, the Murray, South Australia. Coll. 

 Geol. Soc. 



Remarks on the Species. 



The Caryophyllia viola is readily distinguished by the structure 

 of its costse, the rounded and compressed base, the papillary 

 columella, and the tall pali. At first sight it resembles the 

 Pleurocyathi of the German Oligocene, but a careful examination 

 determines its genus readily. The new species has no resem- 

 blance to the Caryophyllia of the Sicilian Pliocene, and it has 

 not any recent allies. The generic name of Cyathina appears to 

 have met with little favour of late; and the species formerly 

 classified under that name are now termed Caryophyllia by M. 

 Milne-Edwards, the old Caryophyllia becoming Lithophyllice. 



The three species of the genus Flabellum are remarkable : one 

 is known to exist at the present day on the Chinese coast, and 

 the others are new to zoology. F. Candeanum and the new F. 

 Victoria are the first instances of fossil Flabella truncata. The 

 species included in this section of the genus have as yet been 

 found as recent Corals in the Chinese, Oceanic, and Australian 

 waters. It was to be expected that some of them, or some ex- 

 tinct members of the section, would be found in the Tertiaries 

 of Australia. 



The F. Gambierense is a pedicellate species, with a low septal 

 number ; and its nearest species (remote, however) is F. Galla- 

 pagense (Miocene). 



The Placotrochi are also remarkable ; for either both the spe- 

 cies indicate that the lamellar columella is an insufficient ge- 

 neric distinction, or they afford an extraordinary example of 

 mimetism in two closely allied genera. The genus Flabellum 

 does not differ from the genus Placotrochus, except that it has 

 no essential and lamellar columella ; but there are parallel spe- 

 cies of both genera with the columellar distinction alone. That 

 is to say, there are pedicellate Flabella and Placotrochi — some 

 compressed, with lateral crests, numerous septa, and wide calices, 

 others without crests, and some are cuneiform : there are trun- 

 cate species of both genera, and in Jamaica (Miocene of Bowden) 

 there is a section in which both genera are costulated and 



