70 CANADIAN FOSSILS. 
aperture as at the base, and about three times as long as their greatest width 
when the stipe is flattened ; inclined to the axis at an angle of from 35° to 
45° ; division-walls of cellules in contact, or united for three fourths of their 
entire length ; margin of the aperture straight, or slightly curved near the 
anterior edge, making an angle of 110° or 112° with the axis ; the anterior » 
margin, in the broader stipes, lies over the base of the third cellule in 
advance. The limits of the cellules are strongly marked by a line imdi- 
cating the place of the partition or divisional cell-wall, which on one side 
often terminates below in a pustule. 
This beautiful little species differs very distinctly from all others of the 
genus which I have studied; and it bears little relation to any of the 
European forms described, so far as they have come under my observa- 
tion. The substance of the stipe is usually thickened, brownish-black in 
color, smooth or slightly wrinkled from desiccation, and rarely marked 
with distinct striz parallel to the cell-margins. The strize apparently 
indicate the successive stages of growth or development of the cell-walls. 
The divisions between the cellules are strongly marked by what usually 
appears to be a distinct groove produced by the folding of one cell over the 
other at the lme of junction, this line indicating the place of the cell-partition. 
The sheath or common body of this species is usually partially filled 
with stony matter, and a section presents an extremely elongated oval 
form. This condition may be partly due to the original character of 
the body, or to the nature of the matrix; which is less finely lammated 
than some of the graptolitic slates, but preserves the fossil in a very beau- 
tiful manner. The imprints are stamed by oxide of iron, and the striz 
marking the divisions of the cellules are often well preserved. The trans- 
verse strize parallel to the apertures of the cells are often distinctly seen in 
casts of the interior. 
The minute tubercles marking one side of the stipe are rarely shown 
on the two sides, and sometimes on neither side. ‘The conditions of 
pressure may have had some influence in causing this appearance ; since 
the pomt of the abrupt bending of the partition between the two cellules 
may have resisted more than the other parts, and thus produced the 
promimence observed. The proportions of parts are subject to slight 
variations, dependent mainly on the degree of stipe-development. In 
the narrower forms, the-cell-aperture often lies vertically above the base of 
the second cellule in advance,,instead of above that of the third as in the 
wider forms. In the relations of the cellules to each other, they appear . 
as if the pressure had been exerted obliquely to the direction of the axis; 
the cellules being slightly en échélon. 'There are however many indica- 
tions pointing to such an arrangement as being the original disposition of 
the cellules on the axis, not only in this but in other species. 
The impressions of G. bryonoides resemble those of this species; but 
