460 THE CANADIAN NATURALIST. [Vol. viiL 



inches in diameter, and from the base of the root to the top of 

 the branches it measures one inch and a half. 



It occurs in the Niagara limestone at Hamilton, Ontario. 



Calyptograpsus subrctiformis, n. e. 



Frond circular, but cyathiform in its growing state. There 

 are numerous bifurcating branches, which in the fossil condition 

 imperfectly unite or overlie each other, producing a kind of fine 

 net- work with irregular sub-rhomboidal interstices. In texture 

 it is corneous, having the^branches marked with striations of a 

 sub-rhomboidal form. 



In this species the branches are much finer (but little more 

 than one-eightieth of an inch in width) than in C. cyathiformis, 

 with more numerous and irregular bifurcations, producing a 

 netted appearance. The original matter is often replaced by 

 pyrites. The fronds are not generally more than two inches in 

 diameter. Only a few specimens have been found, and these 

 show some varietal differences. 



This species was found in the Niagara limestone, Hamilton, 

 Ontario, by Col. Grant. 



Genus Rhizograpsus, n. g. 

 Gr. Rhiza, a root ; grapho, I write. 



Frond flabellate, but cyathiform in growing state ; bifurcating 

 branches with dichotomous terminations; stem terminating in a 

 well-marked bulb ; branches (marked with striae) more or less 

 reticulated, and united, or overlaid by others. 



This genus is established on account of its bulbous root, which 

 as yet has been found in no other species of this family. The 

 numerous branches closely overlie each other or are connected in 

 the form of a net-work without transverse dissepiments, as in 

 Dictyonema. Fragments of these somewhat resemble species of 

 Calyptograpsus-but have a much more netted appearance and 

 the branches are'mucrTmore delicate. 



Rhizograpsus bulbosus, n. s. 



Frond cyathiform in growing state ; numerous bifurcating 

 branches overlie each other, or are united at point of contact to 

 form a net-work, with^fine, r more or less irregular, rhomboidal 

 interstices. The branches unite at base into a slender axis 

 which terminate] in a bulbous root. The branches are usually 



