114 



COELENTERATA— ANTHOZOA 



PHYLÜM II 



Columnopora Nich. {Calapoecia Billings). Like the preceding, but with 

 numerous, short, well-marked septa. Mural pores large, disposed in vertical 

 rows between the septa. Ordovician. 



Fig. 17(3. 



Favosites polymorpha (Goldf.). Devonian ; Eifel. A, Coralluni, natural size. B, CoraUites enlarged, two 

 of them broken open and showing tabulae. C'and D, Transverse and longitudinal sections showing spiniform 

 septa and mural pores {p). (C and B after Nicholson.) 



Emmonsia E. and 

 Ordovician (Trenton). 



H. Ordovician to Carboniferous. Nyctopora Nich. 

 Syringolites Hinde. Silurian (Niagara). 



Pachypora Lind. (Fig. 177). Corallum branch- 



«-— «^»^ ing, composed of prismatic, polygonal corallites, 

 ^ ySKmJIm *^® walls of which are so thickened towards their 

 VU/^Mf mouths by layers of stereoplasma that the calices 

 wMyRjfc appear to have circular contours. Septa very 

 minute ; mural pores scanty, but often of large size. 

 Abundant in Silurian and Devonian. 



Trachypora E. and H. Dendroid with cylindrical 

 stems. Corallites polygonal ; walls so thickened by 

 layers of stereoplasma that the calices become round 

 and greatly contracted, and appear to be superficially 

 widely separated. Mural pores few and irregularly 

 distributed. Septa represented by rows of spines. 

 Tabulae at remote intervals. Common in Devonian. 

 Striatopora Hall (Fig. 178). Like the preceding, but with tubes con- 

 tracted by stereoplasma at a greater depth, so as to give the calices a 

 funnel-shaped appearance. Silurian and Devonian. 



Alveolites Lam. (Fig. 179). Corallum massive or 

 branching, composed of small, contiguous, compressed, 

 thin-walled corallites, with obliquely opening triangulär 

 or semilunar calices. Septa very faint, represented 

 merely by ridges or rows of spinules, sometimes but 

 a Single row present. Mural pores of large size, ir- 

 regularly distributed. Very common in Silurian and 

 Devonian. 



öladopora Hall ; Coenites Eichw. Silurian and Devonian. 



Pleurodidyum Goldf. (Fig. 180). Corallum depressed, discoidal, circular 



Fig. 177. 



Fachypora nicholsoni Frech. 

 Middle Devonian; Eifel. A, 

 Transverse section. B, Longi- 

 tudinal section, enlarged ; p, 

 Mural pores (after Nicholson). 



Fig. 178. 



Striatopora flexnosa Hall. 

 Silurian (Niagara) ; New 

 York. 



