FAMILIES AND GENERA OF THE MADREPORARIA. 161 



IV. Alliance AGARICIOIDA. 

 Colonial Lophoseridae, foliaceous or massive, or incrusting. Calices 

 distinct or indistinct, in series separated by coUines. Septo-costae confluent 

 and extending over the collines. 



Genus Agaricia, Lamarck. 

 Genus Plesioseris, Duncan. 

 • Genus Pachyseris, Ed. & H. 



Genus Comoseris, d'Orb. 



Subgenus Oroseris, Ed. & H. 

 Genus Hydnophorabacia, d'Achiardi. 

 Genus Coscinar.ea, Ed. & [I. 

 The genus Oroseris becomes a subgenus. 



Genus Agaeicia, Lamarck, Si/st. des Anim. sans Verteh. (1801) ; 

 Milne-JEdwards Sf Jules Haime, Hist. Nat. des Corall. vol. iii. 

 p. 80 (1860). 

 Syn. Undaria, Dana. 



Colony foliaceous and irregular in shape. Calices on one or 

 botli surfaces, circumscribed or limited at least on two sides, in 

 transverse or concentric series, which are separated by unequal 

 ridges (collines), over which the confluent septo-costse pass. 

 Columella tuberculous, papillose, or compressed. Septa con- 

 fluent, not numerous. Common plateau striated and naked. 

 Synapticula exist. 



Disfrihution. — Fossil. Miocene of Sind, Asia ; Europe. — Suh^ 

 fossil. Bed Sea. — Recent. Caribbean Sea, Indian Ocean, Bed Sea. 



Genws Plesioseris, Duncan, Journ. Linn. Sac, Zoology, 

 vol. xvii. p. 309 (1883). 

 Syn. Mceandi'oseris, Bousseau (pars). 



Colony massive, adherent, and without epitheca. Surface 

 irregular and nodular. Calices in short series, confluent by their 

 septo-costae and with distinct centres. Septa often uniting, solid, 

 except near axial space, where they are trabeculate witli ascending 

 processes ; granular on the sides, M^arty and spinulose on the 

 free edges. Columella well developed and papillary. Synap- 

 ticula of two kinds : — 1, long, broad, and vertical, in two rows 

 near the true calicular wall ; 2, small and nodular, near the 

 axial space. Eminences between the series of calices covered by 

 septo-costae, and having a true wall. Growth by gemmation 

 beyond and between the calices. 



Bistrihution. — Recent. Pacific. 



LINN. JOURN. — ZOOLOGY, YOL. XVIII. 11 



