64 



Descriptions of New Species of Fossils 



Where there are three or four ranges of cell-pores, the central 

 range, or ranges open directly upward, with the lateral ones open- 

 ing nearly directly outward ; where there are but two ranges they 

 open directly outward. Cell-apertures small, circular, closely ar- 

 ranged and nearly contiguous ; cell-margins but slightly elevated ; 

 margins and intermediate spaces finely granulose. Ranges of pores 

 separated by a narrow nodose ridge. 



Fenestella tantulus n. sp. 



Frond flabelliform, branches straight, seven in the space of five mm. ; 

 on the non-poriferous side rounded and striated ; striae fine, four 

 to six on each branch, strongly granulose : dissepiments from one- 

 half to two-thirds as wide as the branches, expanding at their junc- 

 tion, four in the space of five mm. Fenestrules elongate-oval or sub- 

 quadrangular ; width about the same as the branches, length from 

 two to three times the width. Cell-pores in from two to four ranges, 

 two ranges predominating ; five pores in the length of a fenes- 

 trule ; where there are more than two ranges the inner ones open 

 directly upward and the lateral ones directly outward. Cell-aper- 

 tures small, circular, margins slightly elevated, spaces between the 

 ranges of apertures tortuously striated ; where there are but two 

 ranges of cells they open directly outward ; the interspaces are ele- 

 vated and nodose, but not carinated. 



This may be distinguished from F. conferta by its smaller and 

 more distant cell-apertures, and fewer cells in the space of a fenes- 

 trule, and by its stronger and more closely arranged dissepiments. 



Fenestella pkolixa n. sp. 



Frond flabelliform, branches slender, irregular near the base, be- 

 coming more regular and straighter above, eight or nine in the space 

 of five mm.; non-poriferous side^rounded and striated ; striae sharp 

 and in well-preserved specimens granulose, three or four upon each 

 branch. Dissepiments very slender, occasionally oblique to the 

 branch, slightly expanding at their junction, distant from each other 

 about one millimetre. Fenestrules quadrangular, often twice the 

 width of the branch, the length from two to two and a half times 

 the width. Cell-pores in two ranges, four or five in the length of a 

 fenestrule, opening nearly directly upward, apertures circular, mar- 

 gins distinctl}^ elevated, granulose and indenting the border of the 

 fenestrule ; centre of the branch carinated, carina sharp and strongly 

 elevated. 



