8 4 



NORTH AMERICAN INDEX FOSSILS. 



8 1. S. perelegans Billings. (Figs. 

 134-135.) Devonic. 



Between 5. maclurei and 5. hisingeri. 

 Associated with the preceding species. 



XXXV. Favosites Lamarck. 



Corallum massive, more rarely 

 branching, commonly forming heads 

 which may be a foot or more in diam- 

 eter. Corallites prismatic, thin, in con- 

 tact but not amalgamated by their walls, 

 which are perforated by equidistant 

 mural pores in one or more rows. 

 Septa rudimentary or obsolete. Nu- 

 merous more or less regular tabulae di- 



,i 





Fig. 136b. Favosites venustus 



vide the intrathecal space. Peritheca enlarged sections (N. Y. Geol. 

 present on the under side of the Survey). 

 colony, and usually strongly wrinkled. Ord.-Carb. 



82. F. venustus (Hall). ( = F. hisingeri E. & H. ?) (Fig. 

 136 a-b.) Siluric. 

 Heads hemispheric or spheroidal, up to 2 or 3 feet in diameter, 



with twelve ascending septal spines, generally visible in section. 



Jn the Niagara group (Lockport beds) of New York, Ontario, 

 Michigan, Cumberland Md., Ohio and Kentucky. 



83. F. favosus (Goldfuss). (Fig. 137.) Siluric. 

 Tubes large — up to 6 mm. in diameter with the inside marked 



Fig. 137. Favosites favosus (Ind. Geol. Survey). 



