8 PALEONTOLOGY OF NEW YORK. 



FAVOSITES, Lamarck. 1812. 



FaVOSITES HELUGRBERGIiE, 

 1'l.ATE IV, FIGS. 1, S; PLATK V, FIGS. 1-3; I'l.ATE VI, FIGS. l-«. 



FHPMitf* Hrlderbergkt, Hall. Tw.'iity-sixth Kept. N. Y. State Miis. Nat. Hist., p. 111. 1874. 

 '• Thiity-secoml Kept. N. Y. State Mus. Nat. Hist., p. 145. 1879. 



" •• " Report of State Geologist for 1882. Expl. pi. 4, tigs. 1, 2 ; pi. ">, tiffs. 1-3 ; 



pi. 6, figs. 1-8. 1883. 



CoRALLUM consisting of large, lenticular, depressed convex or heinisphericiil 

 nia.'^.ses; ba.se covered by a strongly wrinkled epitheca. Cell tubes polygonal; 

 their inner surfiice showing evidence of a few strong longitudinal striae. 

 Septa frequent, from ten to fifteen in the space of 10 mm. ; thickness equal 

 to that of the cell walls. Mural pores in one or two ranges, comparatively 

 large, circular, with margins distinctly elevated. Cell walls thin, but fre- 

 quently much thickened near the surface by silicification, and sometimes 

 granulo.se or spinulose on the inner face. On some specimens the cells, at 

 the surface, are nearly equal, having a diameter of about 1.5 mm. ; on other 

 specimens the diameter varies from .60 mm. to 1.5 mm. 



On many specimens some of the cell tubes are larger and less angular than 

 those surrounding them, being a little more than 2 mm. in diameter. A 

 single specimen from Coeymans Landing has slightly larger tubes on one por- 

 tion, while on all the other parts the cells have the ordinary characters. 



This species differs from Favosites Niagarensis, which it resembles in the size 

 of its cells, in having more numerous diajjliragms, and in the mural pores being 

 on the lateral laces instead of at the angles of the cells. 



Formaticm and localities. In the shaly limestone of the Lower Helderberg 

 group, near Clarksville, Albany county. It is here found weathered out from 

 the rock and silicified, frequently a foot or more in diameter. It is also found 

 in several localities in Schoharie county. Smaller specimens of what appear 

 to l>e the same or a closely allied species occur at Cole's quarry, Herkimer 

 county, N. Y. The species likewise occurs near Cumberland, Md., having the 

 cells uniformly somewhat smaller than those of the New York specimens. 



