No. 8.] BPENCER — GRAPTOLITES. 459 



of the frond. This species is easily distinguished from D. gra- 

 cilis — even in fragments — by the branches being exceedingly fine 

 (about one-hundredth of an inch in width), with scarcely that 

 distance between them, and with no approach to the dendritic 

 form of that species. The frond maintains its character even in 

 the young state. The largest frond is three and one-half inches 

 in diameter. 



It occurs in the Niagara limestone at Hamilton, Ontario. The 

 specimen described was obtained by Lieut.-Col. Grant, and pre- 

 sented to the writer. 



Genus Calyptograpsus, n. g. 



Gr. kaluptos, overlaid ; grapho, I write. 



Frond cyathiform, with numerous bifurcating branches, which 

 are dichotomous at their terminations, but are not connected by 

 lateral processes. The branches are marked with striae resemb- 

 ling 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 appearance and texture this genus resembles 

 Dictyonema, but the branches are all independent, not being 

 connected by transverse dissepiments as in that genus, and are 

 only united in one mass at the root. When fallen some of the 

 branches overlie others as in a semi-anastomose form : the general 

 shape of the frond is circular. 



Calyptograpsus cyatliiformis, n. s. 



Frond cyathiform, with numerous bifurcating branches, united 

 only at the base, with no lateral processes ; the axis consists of 

 a black corneous substance, which is striated longitudinally. The 

 fallen frond has some of the branches overlying each other, form- 

 ing a coarse net work. The radicle consists of a well marked, 

 thick, corneous mass. 



The branches are about three-hundredths of an inch in breadth. 

 The specimen under consideration is most interesting. When 

 obtained the frond had a general flabellate form with the radicle 

 well marked, having branches radiating to nearly a semi-circle ; 

 but on trimming the specimen the portion of the stem with radicle 

 was chipped off, and revealed the remainder of a beautiful frond 

 which was now shown to bo circular — thus proving the funnel- 

 shaped character when living. This fossil is two and one-half 

 Vol. VIII. dd No. 8. 



