462 THE CANADIAN NATURALIST. [Vol. viii. 



The larger fronds do not exceed two inches in height, and 

 sometimes have the same width. 



This species was first obtained at Hamilton, Ont., by Col. Grant. 



Genus Ptylograpsus, Hall, Can. Org. Rem. Dec. II. 

 Ptyhgrapsus foliaceus, n. s. 



Frond bipinnately branching. The slender branches are 

 plumose, with delicate pinnules rising alternately from the oppo- 

 site sides of the branchlets. There are angular openings on one 

 side of the pinnules, whilst on the other there arc indistinct 

 corrugations. When viewed from the face, the cellules appear 

 as oval impressions. 



The branches seldom exceed more than half an inch in length 

 and all appear to originate from nearly the same place on the 

 axis. From these numerous parallel pinnules occur on each side 

 of the axis (sometimes as many as sixteen). The pinnules 

 seldom exceed the fourth of an inch in length and rise at a very 

 acute angle. Even if separate branches be found they are easily 

 recognized. They appear to have been attached, but from the 

 specimens before me the radicle seems to have been broken off. 



Like the other members of this group the texture is corneous, 

 but sometimes replaced by pyrites. This species closely resembles 

 the P. plumulosa of the Quebec Group, but is smaller (three- 

 fourths of an inch) and finer in structure, with the relatively 

 longer pinnules. 



It occurs in the Niagara Limestone at Hamilton, Ontario. 



Genus Thamnograpsus, Can. Org. Rem. Dec. II. 

 Thamnograpsus Bartonensis. n. s. 



Stipes single and broad with lineal undulating branohes 

 alternately arranged on opposite sides and having half the thick- 

 ness of the stipe, which is as much as one-sixteenth of an inch 

 broad. The branches which are given off, are usually at right 

 angles with the stipe, and are generally half an inch apart; 

 there being an undulation of considerable length, opposite to their 

 place of attachment. 



Texture corneous and black, the surface being nearly smooth 

 with longitudinal depressions. The branches are usually short 

 and abrupt. 



They occur in the Niagara Limestone at Hamilton, Ontario, 

 and the writer has se3n them in the rock several inches long. 



