430 Thirty-fifth Eeport on the State Museum. 



diameter of the calix ; height 50 mm.; diameter of the calix 30 mm., 

 depth 20 mm. There are two fossettes, one slightly more conspicuous 

 than the other, a depression continuing through the bottom of the 

 calix connecting the two, and forming a continuous depression from 

 one margin to the other ; number of lamella from 100 to 120, alter- 

 nating in size ; near the bottom of the cup twisted and frequently 

 coalescing. 



Formation and locality. (Jorniferous limestone, Falls of the Ohio. 



ZAPHEENTIS, Eafinesque. Bi . . tl 



Zaphrentis inequalis, n. sp: M>w kl**rJ?' r 



Corallum simple, turbinate, acute at the base, regularly explnaing 

 to the margin ; exterior comparatively smooth ; height 20 mm. ; dia- 

 meter of the calix 20 mm., depth 20 mm,, sides quite regularly slop- 

 ing to the center, a space at the bottom 8 mm. in diameter, flat or 

 slightly convex ; fossette commencing posterior to the center and con- 

 tinuing to the anterior margin, at first an oval depression 4 mm. in 

 length and two in width, abruptly narrowing and becoming deep, dy- 

 ing out as it approaches the margin ; number of lamellae 60, alternat- 

 ing in size, the smaller ones about one-third the thickness of the 

 others; near the margin thickened, angular, becoming thin on the 

 sides ; the principal lamellae extend to the margin of the fossette at 

 the center. 



Formation and locality. Corniferous limestone, Falls of the Ohio. 



Zaphrentis complanata, n. sp.Plzf; ft*/. 



Corallum simple, compressed, turbinate, rapidly expanding ; calix 

 oval, oblique ; height of corallum 80 mm.; greatest diameter of calix 60 

 mm., depth on anterior side 50 mm., a space at the bottom 

 20 mm. in diameter, elevated, conical ; tabulae large, numerous, at the 

 center conical, the outward portion quite abruptly turning downward ; 

 lamellae at the margin 6 in the space of 10 mm., alternating in size, 

 broadly rounded, becoming thin as they approach the center, the 

 principal ones continuing to the center, thickened, twisted and coa- 

 lescing with the tabulae, forming a false columella. This species most 

 closely resembles Streptelasma mammiferum, but may be distinguished 

 from that species by its conspicuous tabulae, the different character of 

 the bottom of the calix, and its, proportionally, much greater depth. 



Formation and locality. Corniferous limestone, near Leroy, New 

 York. 



