410 Thirty-fifth Eeport ois" the State Museum. 



continuation in that direction being marked by a single more promi- 

 nent lamella; number of lamellae 62, flattened and of nearly uniform 

 size near the margin, alternating below; a few of the larger lamellae con- 

 verge to the single ray in the line of the f ossette, but the greater portion 

 continue to the center, where they are twisted and elevated forming 

 a false columella. 

 Formation and locality.. Niagara limestone, Eacine, Wisconsin. 



Ptychophyllum fulcratum, n. sp. 



Oorallum simple, broadly turbinate, usually straight ; increasing by 

 calicular gemmation, the buds proceeding from near the margin ; ex- 

 terior with concentric wrinkles and striae; external costae distinct. 

 There are numerous slender exterior processes which served for attach- 

 ment and support. The largest specimen observed has a height of 20 

 mm., diameter of the calix 50 mm.; for some distance from the mar- 

 gin the calix is flat or gently sloping, then abruptly descending, 

 frequently nearly vertical ; a convex space at the bottom from 8 to 12 

 mm. in diameter; number of lamellae 60, of uniform size, .extending 

 to the center where they are twisted and elevated forming a false col- 

 umella ; near the margin they are broad and flattened, becoming thin- 

 ner as they approach the center. In young individuals there is an ob- 

 scure fosse tte which is obsolete in all the older ones observed. 



Formation and locality. Niagara Group, Louisville, Kentucky., 



CHONOPHYLLUM, Edwards and- Haime. 



Chonophyllum vadum, n. sp. 



Oorallum simple, turbinate, straight or slighly curved, acute at the 

 base, regularly expanding to the calix ; exterior with numerous abrupt 

 constrictions, and fine concentric striae ; external costae very distinct ; 

 height 35 mm., diameter of the calix 20 mm., depth 10 mm., sides 

 slightly concave ; a flat space at the bottom 5 mm. in diameter ; num- 

 ber of lamellae 70, flat, and of nearly uniform size at the margin, be- 

 coming thinner and alternating in size below ; the principal ones 

 extending to the center, where they are twisted and very slightly 

 elevated. 



Formation and locality. Niagara Group, Louisville, Kentucky. 



Ohonophyllum capax, n. sp. 



Oorallum simple, broadly turbinate, regularly expanding ; exterior 



with numerous concentric wrinkles and striations. Externally there 



are numerous slender processes, quite evenly distributed, which served 



for attachment and support ; when exfoliated the exterior has a some- 



