SPENCER NIAGARA FOSSILS. 577 



DiCTYONEMA SPLENDENS (BilHngs). 



(Canadian Falseozoic Fossils, vol. ii., part i, 1874.) 



" Frond four or five inches in length and width ; longitudinal 

 stems about one-third of a line wide, and about their own width 

 distant from each other. The connecting bars or dissepiments 

 are very slender and fragile. They seem to vary in distances 

 from half a line to 3 lines. It is probable that, when perfect, they 

 are at a uniform distance of about half a line, and that when they 

 are more remote some of the intermediate ones have not been pre- 

 served. The substance of the stipes is rough, black and shining, 

 and apparently with some irregular longitudinal striae. 



"No cells or serrations can be seen in any specimens examined. 

 There are five or six longitudinal stipes in the width of two lines." 

 (Billings.) 



Fotmation and Location. — Between Cape Gaspe and Cape Ro- 

 sier, Province of Quebec, in Upper Silurian limestone. 



DiCTYONEMA PERGRACiLE (Hall and Whitfield). 



(24th Report of N. Y. State Museum of N. H., 1872.) 



" Fronds irregular, spreading, composed of very fine closely 

 arranged meshes. Longitudinal filaments tortuous, not exceeding 

 a fiftieth of an inch in width, and the spaces between about equal. 

 Transverse filaments much narrower than the others, their dis- 

 tance equal to twice or thrice that of the longitudinal ones, giving 

 to the openings an elongate hexagonal form. Serrations of the 

 margins not observed. Surface of filaments minutely wrinkled." 

 (H.& W.) 



Formation and Locality. — Niagara limestone, Louisville, Ky. 



Genus CALYPTOGRAPTUS. 



Gr. kaluptos, overlaid; grapho, I write. 

 Genus Calyptograptus (Spencer). Can. Nat., vol. viii.. No. 8, 1S78. 



Frond cyathiform or flabellate, with numerous bifurcating 

 branches, which are dichotomous or trichotomous at their termi- 

 nations, but are not connected by true lateral processes. The 

 branches are marked with striae resembling rhomboidal pits ; the 

 axis has a black corneous exterior, and the radicle is composed 

 of a thickened mass of the same texture as the branches. In ap- 

 pearance and texture this genus resembles Di'ctyonct?ia^ but the 



