234 TWEXTY-TEIBD REPORT OX THE StaTE CaBIXET. 



twenty-six ; cell-walls well marked, forming an elevated ridge dividing 

 the cells on the general surface ; the inner wall shows distinctly in some 

 cells, and very slightly in others ; partitions between the rays distant 

 on the surface, but closely arranged vertically. 



For^mation and locality. In the marly beds of the Chemung group 

 at Hackberry, eight miles above Rockford, Iowa. 



Genus — SMITHIA Ed. & Haime. 



SiUTHIA JoHANNI 11. SJ). 

 Plate 9, fig. 10. 



Coral growing in flat, expanded masses. Cells of moderate size, dis- 

 tant from half an inch to one inch from center to center ; the surface 

 of each cell slightly concave, with moderately elevated area surround- 

 ing the central depression, which averages a tenth of an inch in diame- 

 ter ; the larger depressions, not exceeding an eighth of an inch in 

 diameter, and not more than one-fourth as deep as wide, generally 

 situated nearer one extremity of the area, and with the center or coln- 

 mellar portion scarcely elevated. Kays numerous, rounded, from 

 twenty-nine to thirty-nine, alternating in size on the margin of the 

 depression, very flexuous and confluent, forming an irregular, slightly 

 elevated ridge between the cells, and often an angular node at the 

 angles. In a vertical section the lamellae, formed by the surface plates 

 at difierent stages of growth, are closely arranged, and tlie intervening 

 spaces filled by vesiculose partitions. 



Formation and locality. In the marly beds at Hackberry, eight 

 miles above Kockford, Iowa. 



Smithia multiradiata n. sjp. 



Coral forming flat expansions with distant cells ; the border sur- 

 rounding the central depressions slightly raised, leaving depressed 

 interspaces ; depressions, varying from an eighth to a sixth of an inch 

 in diameter. Rays from thirty-six to forty, somewhat strong, rounded, 

 flexuose and confluent. 



This species differs from S. Johamvi in the larger cells, the more 

 numerous, stronger rays, and the larger cell depressions. It is a larger 

 and more robust species. 



Formation a/nd locality. Associated with the preceding species. 



Genus — CYSTIPHYLLUM Lonsdale. 



CrSTIPHYLLrM MUNDULUM 71. SJ). 



Coral small, seldom exceeding one inch and a fourth in lu^irht, 

 turbinate, rapidly spreading from the base to a diameter of three-fourths 



