234 PALEONTOLOGY OF OHIO. 



imbricating. Calice deep, its bottom usually occupied by a group of 

 bullae, with very distinct septal striae, which usually appear to be made 

 up of a succession of elongated vesicles. The internal structure is ves- 

 icular, the largest vesicles being central, and having a diameter of from 

 a line to a line and a half. 



Young examples of C. vesiculomm are strictly simple, but older exam- 

 ples increase in size by a peculiar form of calicular gemmation. In this 

 mode of growth the coral attains a certain size, and then the calice be- 

 comes more or less covered up by the extension over it of the epitheca. 

 A fresh corallite is then produced from the primitive oral disc by gem- 

 mation, either directly in the axis of the old cup or commonly from one 

 side. After this has lived for a certain time, a third corallite is produced 

 in a similar manner, and the process may be continued until an aged 

 specimen may come to consist of six or eight cups arranged in a vertical 

 series, and each springing from some part of the calice of its predecessor. 



An individual of C. vesiculosum of average size has a length of three 

 inches, a diameter of the calice of an inch and a quarter, and a depth of 

 the calice of about the same. 



Positwri and locality: Corniferous limestone, Columbus, Ohio. Collected by Mr. 

 J. H. Klippart. 



Cystiphyllum Ohioense, Nicholson. 



Plate 23, figs. 4, 4a. 



Corallum small, turbinate, straight, or slightly curved, from six to nine 

 lines in height. Epitheca with longitudinal striae, and usually well- 

 marked annulations and constrictions of growth. No calicular gemma- 

 tion nor radiciform productions of the epitheca. Calice not oblique, ex- 

 tremely deep, occupying from half to two-thirds of the total length of 

 the corallum, not flattened at the bottom. The interior of the calice 

 shows more or less distinct septal striae, thirty or more in number. Ves- 

 icles small. 



The dimensions of an average specimen are : length, eight lines ; 

 diameter of calice, six lines ; depth of calice, four and a half lines. 



There can be no doubt as to the specific distinctness of this form, 

 though the examples upon which it is founded are much silicified, and 

 do not exhibit some points of structure so well as could be desired. 0. 

 OMoense is readily distinguished by its uniformly small dimensions, its ex- 

 traordinarily deep, pointed, and not oblique calice, the presence of distinct 



