On the Montiadiporoid Corals of the Cincinnati Gwiip. 35 



Callopora cincinnaticnsis, Ulrich. Jour. Cin. Soc. Nat. Hist., I, 

 93, 1878. The same with query (?). Ibid. , V, 142, 1882. 



Fistidipora (?) multipara, U. P. James. The Palaeonlologist, 

 p. 2, 1878. Supplement to Cat. Foss. Cin. Gr., p, 10, 1879. 



Y. flabdletta, Ulrich. /. c. II, 28, 1879. 



Chdoporcllajlabdlata, Ul. Ibid., V. 257, 1882. 



Fistidipora siluriaiia, U. P. James. The Pala^ont, p. 19, 1879. 



Corallum incrusting, or forming more or less branching or 

 frondose masses; cells in a perfect condition, slightly oblique, with 

 thin walls, but in many specimens direct to the surface, elevated 

 like a ring, and surrounded by from one to two rows ot interstitial 

 cells. Ordinary calices circular or oval ; the interstitial cells often 

 polygonal. Walls thin or thick according to the condition of the 

 specimen. (Plate i. Figs. 6, 6 a, l>, c). 



Obs. This species is one which seems to appear under many 

 forms. Those best known, or at least most common, have direct 

 cells, with thin walls and these are surrounded by numerous small 

 cells in one or two rows. One specimen of the species is very instruc- 

 tive. It is small (Plate I, fig. 6), about an inch in length, spreading out 

 to about half an inch at the broader end, and has at one end circu- 

 lar calices, with thick interspaces, and the wall raised up to form a 

 ring. Toward the center of the specimen the spaces between the 

 cells become filled with cells. Further on the small cells become 

 larger and more irregular, and finally at the end the apertures be- 

 come oblique to the surface, the walls are thin and sharp, the 

 calices are oval, and a very few interstitial cells can be seen. 



It would appear that in a perfect condition the apertures are 

 thin walled and oblique. When they are worn a little the sharp 

 edges disappear, numerous interstitial cells appear, and the open- 

 ings are direct. Finally, still further wear obliterates the mouths 

 of the smaller cells, the larger ones appear to project above the 

 surface, and the intercellular spaces are solid. All these features 

 showing in a single specimen should make us cautious about de- 

 scribing new species of these forms. The four species united above 

 have been considered distinct. Thorough investigation proves the 

 untenableness of the view. We regard cincinnaticusis z\\di flabellata 

 as characterized upon slightly worn specimens, showing a great 

 number of interstitial cells. Multipara represents another phase, 

 less worn than the preceding, with the interstitial cells irregular in 

 form, while siluriaiia represents the same species when it is most 



