KENTUCKY GEOLOGICAL SURVEY. 53 



cylindrical, from 5 or G to 10 or more mm. in diameter, witli 

 low, rounded, ratlier distant monticules, occupied by apertures 

 somewhat larger than the average. Apertures thin-walled, hex- 

 agonal or polygonal, 8 or 9 in 2 nun. WialLs beset with numer- 

 ous acanthopores, which often indent the zooecial apertures. Dia- 

 phragms thin and distant in the axial region; more numerous 

 in the mature region. 



Occurrence : A common form in the upper Eden and in the 

 Mount Hope beds of the Maysville group in the Cincinnati re- 

 gion. The thin-walled, polygonal apertures, often bristling with 

 acanthopores, when the surface is well preserved, are character- 

 istic features of this species. 



5. From the Fairmount Beds. 



ESCHAROPORA HILLI ( JAMES ). 

 Plate 3, figs. 2, 3. 



Zoarium an unbranched, two-edged, flattened frond, cellulif- 

 erous on both faces, expanding gradually from a pointed, stri- 

 ated foot which articulated with the socket of an attached base; 

 from 2 to 5 mm. in thickness at the middle, from 6 to 15 mm. 

 wide, and from 30 to 100 mm. in length. Occasionally a speci- 

 men is found attaining a breadth of nearly 30 mm. Surface on 

 both sides marked by prominent, transverse ridges, 2 mm. or a 

 little less apart, which are usually continuous across from edge 

 to edge and sometimes a little undulating. Apertures oval or 

 lozenge-shaped, arranged between elevated lines in obliquely 

 diagonal, intersecting series, which are continuous over the 

 ridges ; about 8 or 9 in 2 mm. Internal structure about the same 

 as in other species of the genus. 



Occurrence: The two specimens, on opposite sides of a 

 small slab, from which the species was described by Mr. U. P. 

 James, were found on the bank of the Ohio river at Cincinnati. 

 Evidently they had been drifted to that point. This species was 

 afterwards found in considerable abundance by Mr. E. O. Ul- 



