Upper Ilelderherg Group, 



169 



ranges occur the intervening space is smooth, when two ranges 

 occur they are separated by ridges. 



ZocaZi/?'— Canada West. 



Fenestella peruj^data, n. sp. 

 Infundibuliform, strongly undulating on a line with the branches; 

 width of branches from one to 1.50 mm., angular and in well-preserved 

 spt^cinu n* slightly carinated ; dissepiments or anastomosed portions; 

 equaling or greater than the width of the branches ; fenestrules vary- 

 ing Irom elongate to broadly oval, width equal to or a little more 

 than the v/idth of the branch, length one and one-half times the 

 width of the branch ; cells in from three to six ranges, apertures circu- 

 lar arranged in sinuous longitudinal rows, 16 in the space of five 

 mm. 



Locality — Canada West. 



Fenestella hexagonalts, n. sp. 



Infundibuliform, br-oadly spreading; width of branches from .50 to 

 one mm. ; angular, slightly carinated, sometimes connected by dis- 

 sepiments, at other times anastomosing, when anastomosing de- 

 cidely zig-zag, dissepiments or anastomosed portion .66 mm. in width; 

 on celluliferous side the branches are regularly sinuous, never zig- 

 zag ; fenestrules, from .65 to one mm. wide, length to one and one- 

 half times the width ; cells in from two to four ranges, arranged in 

 longitudinal sinuous rows, 17 apertures in the space of five mm.; be- 

 low bifurcations a triangular space without apertures. 



Locality — Canada West. 



Fenestella HEXAGOjq-ALis var., roRAMTNULOSA, n. var. 

 On the celluliferous side of the branches, at irregular but frequent 

 intervals, are prominent nodes, apparently formed by the coalescing 

 and elevation of adjoining cell apertures, having a height of .25 mm. ; 

 diameter at the base, .35 mm. 



Locality — Canada West. 



Fenestella letinodata, n. sp. 

 Infundibuliform, branches strong; bifurcations occurring at inter- 

 vals of from 5 to 20 mm., branches sometimes straight, usually more 

 or less sinuous and sometimes decidedly zig-zag ; dissepiments from 

 two-thirds to equal the widt h of the branches , fenestrules somewhat 

 variable, but usually oval or obscurely hexagonal, length, one mm., 

 22 



