ANTHOZOA—TETRACORALLA. 71 



47. S. striatus Owen. Siluric. 

 Much larger than the preceding, the calices ranging to 40 mm. 



in diameter. Elevation around central pit pronounced. 

 Occurs with the preceding. 



48. S. mamillatus Owen. Siluric. 

 Margins of calices depressed, center strongly elevated with a pro- 

 nounced crater-like pit at the top from 4 to 5 mm. in diameter. Dis- 

 tances between centers of pits of adjoining corallites 10 to 20 mm. 



In the Niagara beds of Michigan, Iowa, Kentucky, Indiana, etc. 



XXI. COLUMNARIA GoldfuSS. 



Heads consisting of prismatic corallites, like that of Favosites, 

 but without mural pores, and with the septa either well marked or 

 indicated by vertical ridges. Tabulae well developed. Ord.-Dev. 



49. Columnaria halli. (= C. alveolata of most authors.) 



Middle Ordovicic. 



Septa represented by from 20 to 40 vertical ridges. Tabulae flat, 



close and smooth in the centers. Tubes variable in diameter 



from 2 to 5 mm.; sometimes 10 mm. tubes, 



occur among the smaller ones. 



In the Black River limestones of New 

 York, Canada and Michigan, and in strata of 

 the same age in Wisconsin, Illinois and Iowa, 

 etc. 



50. C. alveolata Goldfuss. (= Favistella 

 Fig. no. Columna- stellata Hall.) (Fig. I IO.) 

 Ha alveolata. Horizon- Upper Ordovicic to Siluric. 



tal and vertical sections -r L l „ *. ^ j- 



, . lubes varying from 3 to o mm. in diame- 



(Lambe). , 



ter. Septa from 20 to 30, alternatingly larger 



and smaller, the former extending to the center. Center of tabulae 



marked by the septa. Common in the beds of the age of the 



Cincinnati group throughout the central west Also recorded by 



Rominger from the Niagara Group of Point Detour. 



XXII. Eridophyllum E. & H. 

 Heads composed of loosely aggregated cylindrical corallites each 

 surrounded by a wrinkled epitheca, from one side of which pro- 

 longations extend uniting adjoining corallites. An inner wall en- 

 closing a narrow tabulate area is present. Sil.-Dev. 



