RELATIONS OF CHONOPHYLLUM. 267 



The genus Conophyllum was founded upon a group of corals from the 

 lower Niagara of New York, described by Professor Hall as Conophyllum 

 niagarense. For reasons already pointed out, these have been quite gen- 

 erally included under Chonophyllum, and Mr. S. A. Miller figures a speci- 

 men as illustrative of this genus.* Alter examining a series of specimens 

 from New York, Michigan, Indiana, Kentucky and Iowa, we have no hesi- 

 tancy in assigning them to Cystiphyllum, although the septa are at times 

 more than ordinarily well developed. The specific description and the 

 figures given by Hall leave no doubt as to the position of these forms : 



"Irregularly cylindrical, elongated or subturbinate, more or less expanding 

 above, externally rugose at intervals (when weathered often very rough) ; cup 

 regularly concave, deep; lamella' thin, distance from each other equal to their 

 thickness, denticulated on their upper and inner edges ; transverse dissepiments 

 corresponding to the concavity, and forming the cell or cup, and extending upwards 

 to the margin. 



"In this fossil, the rays become in fact subordinate to the dissepiments; and the 

 character would be more correctly denned, by describing the coral to consist of a 

 series of concave discs or inverted cones setting one within the other, having their 

 upper surface marked by radiating rows of denticles. The form is very irregular, 

 varying from small, short, turbinate forms to elongated cylindrical ones in which 

 the diameter scarcely varies throughout. The weathered surfaces present the 

 arrangement of the dissepiments more or less perfectly in numerous specimens. I n 

 one or two instances, I have seen specimens where the weathering developed the 

 rays more prominently than the dissepiments, and in such instances the surface is 

 beautifully denticulated." 



4. Chonophyllum 'nuignijinmi, Billings. 



Chonophyllum magnificum, Billings. Can. Jour., new ser., vol. v, 1860, pp. 



264-265, pi. i. 

 Rominger. Geol. Sur. of Mich., vol. iii, pt. ii, 



1876, p. 116, pi. xliii. 

 Davis. Kentucky Fossil Corals, pt. ii, 1885, pi. 



101. tig. 3; pi. 103, figs. 12, 13. 14. 



This species, to which frequent reference has been made, was founded 

 by Billings in 1860 upon a specimen imbedded in a mass of Devonian 

 Limestone, Walpole township. Canada West. He was entirely misled by 

 the very peculiar septal formation, supposing the broad septa to represent 

 the interseptal cavities, and the narrow grooves of the calyx to mark" the 

 position of the septa. His description reads as follows: 



" Short, turbinate, expanding to the width of six or seven inches at a height of four 

 inches and a half; upper surface constituting a nearly Hat circular disc, with a 

 rounded cavity in the middle, one inch and a half wide, from winch radiate one 



+ X. \. Geol and Pal., 1889, p. 177. 



