NEW GEiNBRA OF lALEOZOIO RUGOSE CORALS 



207 



extremity of the carina. In a transverse section, curved, spur- 

 like processes are seen proceeding from the sides of the septa. 

 The nature of these processes has not been satisfactorily deter- 

 mined. Tabulae are frequent, delicate; dissepiments frequent. 

 The type species of this genus closely resembles Stereo- 

 lasma rectum, and from external characters alone they 

 could not be separated, but by slightly grinding down the ex- 

 terior, the difference can be at once seen. 



21 22 



Fig. 21 Longitudinal section of ttie same showing depth of the calyx, 

 pseudocolumella and septal carinae 

 22 Longitudinal section near the margin, showing the edges of the 

 septa and the width of the carinae 



KiONELASMA, gen, nov. 



Type: Streptelasma mammifm^um Hall. Fossil corals of the 

 Niagara and Upper Held, groups. 1882. p. 21, and 35th rep't 

 N. Y. state mus. nat. hist. 1884. p. 425. Onondaga limestone, 

 Falls of the Ohio. 



Examples: Gyathaxonia gainesi Davis. Kentucky fossil 

 corals. 1885. pi. 104, fig. 1-7. 



Streptelasma spongaxis Rominger. Geol. sur. Michigan. 1876. 

 pt 2, pi. 39. 



Corallum variable in size, cylindrico-conical or horn-shaped; 

 oalyx circular or elliptic; septa alternating in size, the larger 



