18 PROF. P. MAETIN DTINOAN's BEYISION OP THE 



G-enus PjiATYTEOCHUS, MM. Milne-Edwards Sf Jules Haime, 

 Ann. des Set. Nat. 3' ser. t. ix. p. 246 (1848). 



The corallum is simple, straight, cuneiform, and non-adherent. 

 The eollumella is essential, elongate, and fascicular, and has a 

 free papillary edge. The septa are broad and exsert. The wall 

 is naked, and there are two kinds of costse : those on the 

 middle of the broad surfaces of the corallum enlarge towards the 

 calice, and those on the edges of the corallum near the base are 

 extended and large. The compressed base is with or without a 

 conical point. 



Distribution. — Fossil. Eocene: Alabama. — Recent. Australian 

 seas ? 



This genus was founded to include two species from Alabama 

 which had been placed by Lea amongst the Turbinolians, and 

 one of them in the genus Endopacliys by Lonsdale. The forms 

 are remarkable, and very Placotrochoid in appearance. There is, 

 however, a lamellar fascicular columella, and the extension of the 

 costse is almost unique. 



IV. Alliance TURBINOLOIDA. 



Simple Turbinolidse, free or attached, straight, conico-cylindrical, rarely 

 cornute. Septa uniting more or less with a styliform columella which 

 projects. Some forms with pali, with or without a columella. 

 Genus Turbinolia, Ed. & H. 



Subgenus Stylotrochus, E. de From. 

 Genus Stylocyathus, d'Orb. 

 Genus Conocyathus, d'Orb. 

 Genus Bistylta, Teunison Woods. 

 Genus Trematotrochus, Tennisou Woods. 

 Genera absorbed: — Pleurocyathus, Keferstein, by Stylo- 

 CYATHUS, d'Orb.; Stylocyathus, Reuss, =Stylocya- 

 THUS, d'Orb. 

 Stylotrochus becomes a subgenus. 



Grenus Tuebinolia, MM. Milne-Edwards ^ Jules Uaime^ Hist. 

 Nat. des Gorall. vol. ii. p. 60. 



The corallum is simple, free, straight, and conical, rarely curved 

 or cornute. The calice is circular in outline. The columella is 

 essential, and projects in the calice like a stylet. The septa are 

 exsert. The costse are lamellar and project, are straight and 

 perfect. Intercostal spaces with or without fossettes. 



Distribution. — Fossil. Eocene : England, Erance. Oligocene : 

 Germany. — Recent. Caribbean Sea? 



