192 



Bryozoans of the 



separated by striations, the one separating the central rows somewhat 

 larger than the others, and giving to portions of the branch a sub- 

 carinated appearance; occasionally only this ridge is present^ non- 

 cellnliferous space at margin .33 mm. in width, flattened, smooth or 

 granulose ; margins sometimes crenulatedc 

 Locality — Belloua and York, N Y 



GENUS T^NIOPORA, Mch, 



Frond growing as a flattened stipe, from which proceed opposite 

 or alternating lateral branches i along the middle of each branch 

 is a sharp elevated carina , frond cellnliferous on each face, cells aris- 

 ing from a mesial epitheca : apertures arranged in longitudinal parallel 

 rows, sometimes in oblique ascending rows. 



Tjeniopora exigua. 

 Tceniopora exigua Nicliohon. Palceontology of Ontario, p. 108, 1874. 



Lateral branches diverging at an angle of 80 degrees, width 3.50 

 mm.; thickness of transverse section .75 mm. , height of carina ,75 

 mm. ; cells tubular, for the greater portion of their length parallel 

 with the epitheca, opening directly outward ; cell-apertures circular ; 

 non-celluliferous space at the margin 50 mm. in width ; the rows of 

 cells at middle of branch smallest ; each succeeding row larger; the 

 number of rows differ from 2 to 5, but all intermediate forms occur. 



Zoc«?i^?/— Bellona, and numerous other localities, New York and 

 Canada 



GENUS PTEKOPORA, nov, geyi 

 Frond consisting of a main axis witli numerous branches ; axis tri- 

 angular; sides equal concave; cells arising from internal plates which 

 radiate from the center to each angle; apertures arranged in longi- 

 tudinal rows ; margin at angles destitute of apertures. From each 

 angular margin proceed branches, diverging at an angle of 40 degrees, 

 simple or branching ; transverse section lenticular, along the middle 

 of each side are sharp, strong carinations , branches celluliferous on 

 each face ; cells arranged in longitudinal rows. 



PtEROPORA DUOGEls^ERIS, 11. Sp. 



Axis triangular, width of each face G mm., equally concave. The 

 lateral branches are like those of Tseniopora, from which it may be 

 distinguished by the central axis. 



Locality — In a loose mass at Unadilla Forks, N. Y. 



