OF THE LARAMIE FORMATION OF CANADA. 25 
Aralia notata. Fragments of this leaf were obtained by Dr. G. M. Dawson in the region of 
the Souris River in 1874, but they were too imperfect for description. Dr. Selwyn, how- 
ever, found in 1878 in the Upper Laramie sandstones of Roche Percée, on Souris River, 
very perfect specimens, which I noticed in the Report of the Geological Survey for 
1879-80, Dr. Selwyn having kindly placed his specimens in my hands for study. Some of 
these are a foot in diameter, and they show some points of structure not before noticed. 
I may, before referring to these, quote Newberry’s description, which is very full 
and accurate. 
“Leaves large, one and a half feet in length and breadth, petioled, 3 lobed, or sub-5 
lobed, lobes acute, margins of lobes and base entire, or near the summits of the lobes 
delicately sinuate-toothed ; nervation strongly marked, generally parallel; medial nerve 
straight, two basilar nerves of nearly equal length and strength diverge from it at an 
angle of 30°-35°, are straight throughout and terminate in the apices of the principal 
lateral lobes. Above the basilar nerves about 16 pairs of lateral nerves are given off from 
the midrib at about the same angle; these are nearly straight and parallel, terminating in 
the teeth of the margin. From each of the basilar nerves diverge about the same number 
of pairs of branches as from the mid-rib, and these are nearly straight and parallel 
terminating directly in the margin. Of these the second and third exterior one on each 
side, is often much the strongest of the series, and is then prolonged into a small but 
distinct lateral, triangular, acute lobe, giving the leaf a somewhat pentagonal form. From 
this basilar branch of the lateral nerves, 12 or more short, generally simple branchlets, 
spring on the lower side, and 4-5 on the upper side, near the summit, all of which ter- 
minate in the margins. The tertiary nerves connect the adjacent secondary nerves nearly 
at right angles. Sometimes they are straight and parallel, but oftener more or less broken 
and branching where they meet, near the middle of the interspaces. Where the systems 
of nervation of the lateral and middle lobes come in contact, the tertiary nerves are 
stronger and form a somewhat irregular network, of which the areolæ are large and sub- 
quadrate.” 
The above description corresponds perfectly with Dr. Selwyn’s specimens, except 
that only the right basilar nerve sends off a large branch terminating in a lobe; that on 
the left side having somewhat equal branches. 
As to the affinities of the leaf, Newberry remarks that the texture is thicker and the 
surface smoother than most sycamores, resembling in this some tropical leaves ; but as the 
radical structure is that of Platanus, and the associated plants indicate a HUE anal climate, 
he refers the plant to that genus. 
Lesquereux, in describing his Aralia notata, gives nearly the same characters, except 
that he characterizes the secondary nerves as camptodrome, or bending before they reach 
the margin. He admits that he would consider it identical with Newberry’s species but 
for this feature, and further adds that in one of his specimens the outer véins appear to 
be craspedodrome and to terminate in small teeth, and he refers to other cases in which 
such characters are inconstant. In Dr. Selwyn’s specimens, while in the basal part of the 
leaf the veins bend somewhat toward the margin, which is entire, in the upper part they 
run straight to the margin, and terminate in short teeth, separated by broad, shallow 
sinuses. Thus these specimens satisfactorily unite Newberry’s and Lesquereux’s species. 
Dr. Selwyn’s specimens, however, and others subsequently collected by myself at 
Sec. IV. 1886. 4. 
