138 



Cincinnati Society of Natural History. 



cells, which are made conspicuous by the fact that they are slightly 

 larger than the average, and are separated b} r more numerous inter- 

 stitial cells. In tangential sections the tubes are sub-triangular or 

 oval, and surrounded by usually two rows of very irregular interstitial 

 cells. In vertical sections the interstitial spaces are occupied by a 

 vesicular tissue. 



Formation and locality: In the shaly limestones of the Kaskaskia 

 Group, near Point Burnside, on the line of the Cincinnati Southern 

 Railroad. At this locality the slabs of limestone are, to a great ex- 

 tent, made up of the remains of Bryozoa. 



Eridopora punctifera, n. sp. (Plate VI, fig. 3). 



Externally this species differs conspicuously from the preceding, in 

 having smaller, sub-circular and less oblique cells, comparatively 

 wider interstitial spaces, and more pronounced (i lip," which com- 

 pletely surrounds the cell-aperture, but is always more prominent on 

 one side than on the other. Besides, small but distinct "maculae" are 

 developed at intervals of about .2 inch. About eight cells occup}- the 

 space of .1 inch. The cells over a portion of the surface of a specimen 

 of this species, have their mouths closed by opercula with a central 

 perforation. In tangential sections the tubes are usually sub -ovate 

 and surrounded by two or three rows of very irregularly shaped 

 interstitial cells, which also vary very much in size. Many of the true 

 tubes present two longitudinal lamellae, or spines, which project into 

 the tube cavity, and are placed on opposite sides of the tube. Longi- 

 tudinal sections demonstrate that the interstitial spaces are occupied 

 by a close network of vesicular tissue. The tubes are nearly at right 

 angles to the surface, and occasionally are crossed by a delicate dia- 

 phragm. 



Formation and localit}'. Same as the preceding. 



All unbiassed students of this difficult class of fossils must, after a 

 careful examination into the facts I have here laid before them, come to 

 the conclusion that an intimate relationship exists between the Ceramo- 

 poridce and the Fistuliporidce, which, as I believe I have shown, admits 

 of being readily demonstrated. 



Spatiopora cmistulata, James, and S. lineata, Ulrich, in their ob- 

 long cell-apertures, exceedingly thin and parasitically attached zoaria, 

 are not unlike the typical species of Palceschara, Hall. The onl}' 

 differences of any importance between such species of Spatiopora and 

 Palceschara are that (1), a few large spiniform tubuli are developed in 



