122 Cincinnati Society of Natural History. 



Corallum incrusting, or forming more or less branching or fron- 

 dose masses : surface smooth : calices in perfect specimens slightly 

 oblique, or arched, with raised and very thin margins; in slightly 

 worn specimens calices circular or oval, often with a ring-like margin 

 and surrounded by one or two rows of polygonal interstitial cells : in 

 specimens still more worn the cell apertures have thicker walls and 

 interstitial cells are ill-defined. (Cat. Foss. Cin. Group, 1875, P- 3» as 

 Cera??iopo?-a.) (Fistulipora ? multipora James. The Paleont. , 1878, p. 

 2; F. siluriana James, Ibid, 1879, P- J 9> flabellata Ulnch, Jour. 

 Cin. Soc. Nat. Hist., vol. 2, 1879, P« 2 %-) 



Locality. — Cincinnati. 



Remarks. — The names cited as synonyms above are believed to 

 have been given because of the various aspects a single species pre- 

 sents under different conditions. A single specimen will sometimes 

 show in one position the arched, thin-walled apertures : in another the 

 ring-like, circular aperture with numerous interstitial cells, and in still 

 another place an absence of interstitial cells, It has been mainly upon 

 these features that the above names have been given. What was 

 described as F. siluriana was a worn state with thick intercellular 

 spaces: flabellata is a less worn condition with 'numerous interstitial 

 cells: and multipora is still less worn with a smaller number of irregu- 

 larly shaped interstitial cells. 



87. — M. (Fistulipofa) milfordensis James, 1878. 



Corallum incrusting, generally growing on crinoid stems, and ^ 

 to ^ a line thick: surface smooth: calices oval or sub- polygonal, 

 not arranged in any regular order : walls of calices elevated, some- 

 times in contact with neighboring calices, and sometimes separated : 

 in the latter case the intercellular spaces with many small, irregular 

 calices. (The Paleont., No. 2, Sept., 1878, p. 11 as Callopora.) 



Locality. — Hamilton and Clermont counties. 



Since the first portion of this paper was published the following 

 species has come to light. The description was found among the 

 papers of Mr. U. P. James, and the specimen was in his collection. 

 This is now in the Chicago University. The illustrations were made 

 from the type specimen. It is believed to be sufficiently distinct from 

 all described species to warrant a name. 



