428 Thirty-fifth Eeport on" the State Museum. 



aulacophyllum cruciforme, 71. sv* 

 Corallum simple, turbinate, regularly curved, length of posterior 

 side 25 mm., of anterior side 60 mm.; calix oblique, slightly oval, 

 length 40 mm., width 35 mm., quite regularly concave; fossette com- 

 mencing just posterior to the center and for the space of 10 mm. very deep 

 and pyriform, narrowing and continuing to the anterior margin; number 

 of lamellae 140, at the margin of nearly uniform size, alternating below ; 

 the larger lamellae, with the exception of those which converge to the 

 fossette, continue fco within 8 mm. of the center of the calix, leaving 

 a convex space 16 mm. in diameter nearly smooth ; at the junction of 

 the posterior and anterior lamellae are two rudimentary fossettes, at 

 right angles to the principal one. This species is distinguished from 

 A. undulatum by the conspicuous pyriform fossette,, the smooth space 

 at the bottom of the calix and the more conspicuous lateral fossettes. 

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



AULACOPHYLLUM PR^ECIPTUM, n. Sp. 2*1%-]. P £ o ^ 



Corallum simple, turbinate, straight or slightly curved; exterior 

 with strong annulations, concentric wrinkles and fine striae; longi- 

 tudinal striae fine, distinct ; height of corallum 50 mm.; diameter of 

 the calix 40 mm., depth 30 mm., sides regularly sloping to the center? 

 the calix having the form of an inverted cone ; principal fossette nar- 

 row, extending from the center nearly to the margin ; number of 

 lamellae 120, of nearly uniform size at the margin, alternating below; 

 There are two rudimentary fossettes, at right angles to the principal 

 one ; the lamellae of the posterior side converge to the principal fossette, 

 a few to the rudimentary fossettes, the remaining larger lamellae con- 

 tinue to the center of the calix. 



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



AULACOPHYLLUM REFLEXUM. n. Sp. J*2 3-7, /J*«?>^ 



Corallum simple, elongate, turbinate ; exterior comparatively 

 smooth; height 40 mm., diameter of the calix from 20 to 25 mm., 

 depth 15 mm., sides nearly vertical ; fossette conspicuous, extending 

 from the center to the margin ; number of lamellae 80, alternating in 

 size, the smaller ones being about one- third the thickness of the others 

 and extending but a short distance from the margin ; a portion of the 

 larger lamellae converge to the fossette, and their extremities on the 

 side of the fossette are turned backward; the lamellae opposite the fos- 

 sette extend beyond the center to the bottom of the fossette ; the re- 

 maining lamellae do not reach the center of the calix, their extremi- 

 ties forming a line at right angles to the fossette. There are two 

 rudimentary lateral fossettes. 



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



