GRAPTOLITES. 71 
the stipes are broader, the striz less rigid and distinct, and the tubercles 
and coarser denticles of G. nitidus are absent. In mode of growth and 
general aspect, this species resembles G. serratulus of the Hudson River 
group (Pal. N. Y., vol. 1, p. 274, pl. Ixxiv, fig. 5 a, 6); but in the latter 
the denticles are coarser and more oblique, the lower side bemg much the 
longer, and the stipes are more distinctly lmear; while in G. nitidus the 
stipes become gradually wider from the base, and are very distinctly striate 
and pustulose in well-preserved specimens. 
EXPLANATIONS oF FiguRES OF GRAPTOLITHUS NiITIDUS, Hall. 
Puate I. 
1. A young individual preserving the radicle and the two stipes. 
2. The extremity of a stipe enlarged, showing the partially-developed cellules. 
3. A larger specimen of similar character to fig. 1, showing the pustules at the 
base of the cellules. The extremities are not quite entire. 
4. A part of the left side of fig. 3 enlarged, showing the pustuliform elevations. 
5. An enlargement from another specimen, with the cellules obliquely compressed, 
and the pustules obscurely shown. 
6. Two smaller individuals, which, from juxtaposition, similarity of size, etc., seem 
as if they may have originated from a common base. 
7. An impression of a more extended form, which is proportionally narrower than 
fig. 3. 
8. A still narrower form of stipe, diverging almost rectangularly from the direc- 
tion of the radicle. 
9. A well-preserved small individual, enlarged three diameters. 
Formation and Locality.—Shales of the Quebec group; Point Lévis. 
2. GRAPTOLITHUS PATULUS, Hall. 
Plate I, figures 10-15. 
(G. patuLus, Hall: Geological Survey of Canada, Report for 1857, page 131.) 
Description.—Frond composed of two simple stipes diverging almost 
rectangularly from a small radicle. Stipes long, linear, widening very 
gradually from the base to the extremities, which are somewhat rounded 
from the immaturity of the later cellules. Width from base of serratures 
to the back of the stipe, from one sixteenth to one twelfth of an inch. 
Surface strongly striate in the direction of the cellules; strize curving. 
Radicle minute. The proportion of the stipe occupied by the common 
body varies from a perceptible line to one fifth of the entire width, and is 
dependent partly or entirely on the direction of the pressure. 
