U2)j>er Helderherg Group. 



163 



width, depressed . fenestrules varying from elongate oval to circular, 

 length .75 mm. j cells in from three to six ranges, 18 in the space of 

 five mm. , along the middle of the branch is a row of thin elevations. 



Locality — Falls of the Ohio river. 



Fexestella quadrangularis, n. sp. 



Infundibuliforra ; branches from .50 to one mm. in width on non- 

 celhiliferous side^ angular, nodose ; dissepiments from one-half to 

 two-thirds the width of the branches; on non-celluliferons side angu- 

 lar and carinated; fenestrules, oval , length .75 mm.; cells in from 

 three to six ranges; apertures circular, 18 in five mm.; margins ele- 

 vated, occasionally near base celluliferous side nodose. 



Locality — Falls of the Ohio river. 



Fenestella aculeata, n. sp. 



Infundibuliform ; branches from .50 to .65 mm. in width ; non- 

 celluliferous side rounded, flattened just below bifurcations, with 

 numerous, promment, irregularly arranged nodes ; dissepiments from 

 one-half to equal width of the branches; fenestrules oval or sub- 

 quadrangular, length .65 mm.; width .50 mm., cells in from two to 

 four ranges; apertures circular or oval, 16 in the space of five mm., 

 between the ranges of apertures are numerous sharp conical spines. 



Locality — Falls of the Ohio river. 



Feijestella submutaxs, n. sp 



Infundibuliform ; lax ; branches 35 to .50 mm. wide; on non-cellu- 

 liferous side, round or angular; dissepmients from .25 to 55 mm, in 

 width, rounded, depressed, fenestrules variable, usually subquadran- 

 gular, length 1 mm., width from =25 to .75 mm.; cells in from two to 

 four ranges; apertures circular, 18 in the space cf 5 mm.; ranges 

 separated by granulose ridges. 



Locality — Falls of the Ohio river. 



Fenestela ltneanoda, n. sp. 



Infundibuliform; branches from 50 to one mm. wide ; non-cellu- 

 liferous side angular, slightly carinated, with strong conical nodes ; dis- 

 sepiments .30 mm. wide, frequently carinated ; fenestrules elongate 

 oval or subquadrangular, width from .50 to .65 mm., length twice the 

 width ; cells in from two to four ranges; apertures circular, ranges of 

 apertures separated by a thin ridge. 



