82 



COELENTERATA— ANTHOZOA 



PHYLUM 11 



Duncanella Nich. Corallum top-shaped. Septa nearly all of uniform 

 length and size, forming a spurious columella in centre of the deep calice, 

 exsert at the base. Silurian ; North America. D. horealis Nich, 



Petraia Miinst. (Fig. 103). Turbinate or conical. Septa short, reaching 

 to the centre only at the base of the very deep calice. Columella absent. 

 Ordovician to Carboniferous. 



Folycoelia King (Fig. 104). Horn-shaped. Calice very deep ; four prin- 

 cipal septa reach nearly to its centre, between which in each quadrant are 

 five shorter septa. Zechstein. 



Kanophyllmn Dyb. Ordovician and Silurian. 



Fio. 102. 



Cyathaxonia 

 cornu Mich. Car- 

 boniferous Lime- 

 stone ; Tournay, 

 Belgium. Cor- 

 allum with 

 fractured theca, 

 showing open in- 

 ter.septal loculi. 

 2/i. 



FiQ. 103. 



Petraia radiata 

 Miinster. Devonian ; 

 Enkeberg, near 

 Brilon. i/j. o, Cor- 

 allum viewed from 

 the apex ; b, Trans- 

 verse section below 

 the middle. 



Fig. 104. 



Folycoelia •pro- 

 funda (Germ.). 

 Zechstein; 

 Gera. i/i (after 

 Roemer). 



Fig. 105. 



Palaeocyclns por^nta 

 (Linn.). Silurian ; 

 Gotland. a, Top 

 view of calice ; i!;, 



Fig. 106. 



Microcyclus dis- 

 cus Meek and 

 Worth. Hamil- 

 ton (Devonian) ; 

 North America, 

 i/j. a, Corallum 

 from below ; 

 h, from above 

 (after Nicholson). 



Family 2. Palaeocyclidae Dybowski. 



Coralla simple, discoidal or bowl-shaped. Septa mimerous, stout, approaching 

 radial symmetry in disposition. Tabulae and dissepiments wanting. 



Palaeocyclus E. and H. (Fig, 105). Discoidal to depressed top-shaped, 

 Avith epitheca. Septa numerous, radially disposed, the larger ones reaching 

 to the centre. Silurian. Type, P. porpifa (Linn.). 



Combophyllum, Baryphyllum E. and H. Devonian, 



Hadrophyllum E, and H. Cushion-shaped, with epitheca. Calice with 

 three septal fossula, that of the cardinal septum being the largest. Devonian; 

 Eifel and North America, 



Microcyclus Meek and Worth. (Fig. 106). Like the preceding, but with 

 only one septal fossula, Devonian ; North America, 



Family 3. Zaphrentidae Milne Edwards and Haime. 



Coralla simple, turbinate, conical or cylindrical; septa numerous, exhibiting 

 distinct bilateral symmetry in arrangement. Theca generally formed by fusion of 

 septal ends. Tabulae completely developed ; dissepiments not very abundant in inter- 

 septal locrdi. 



Streptelasma Hall (Fig. 107). Turbinate, often curved. Septa numerous 



