36 FLORA OF THE MONTANA FORMATION. 
of P. melanaria, but it is also exactly the same as P. melanarioides, the 
only difference being the more or less hypothetical teeth. If other 
specimens should be found which possess teeth, the retention of P. 
meJanaria would of course be rendered necessary, but as no other 
examples have ever been obtained, I have decided to refer the speci- 
men to P. melanar hides. 
The fragment agrees in every particular, so far as can be made out, 
with Lesquereux's type, and there can be no doubt of their identity. 
This species, as Lesquereux has pointed out (Tert. FL, p. 147), is 
evidently related to P. tremulcefolia Sap., 1 from which it differs in 
having an entire or slightly undulate margin, and in having all the 
branches of the secondaries enter the margin. Its suggested resem- 
blance to P. Massiliensis Sap. 2 is less plain than its resemblance to the 
former species. The nervation and shape are quite different. P. obtrita 
Dn., 3 from the Similkameen Valley, British Columbia, is thought by its 
author to be allied to the species under discussion, but while this may 
be true, it differs in so many important particulars that it can not be 
regarded as at all closely related. Some of the leaves described as P. 
arctica possess not a little resemblance to P. melanarioides, but this can 
not be regarded as specific. 
Habitat, — Point of Rocks, Wyoming. 
Populus Wardii n. sp. 
PI. VI, fig. 7. 
Leaf of firm texture, approximately circular in general outline, trun- 
cate at base (apex destroyed) ; margin regularly, rather coarsely den- 
tate, the teeth obtuse; nervation strong, coarse, palmately five-nerved; 
the middle nerve or midrib slightly stronger than the others, straight, 
with two pairs of remote, opposite secondaries, these ilexuose and 
anastomosing; second pair of basal nerves nearly as strong, straight, 
Ilexuose, and freely anastomosing with the lower pair of secondaries 
on the midrib, and branching on the lower side and joining with the 
lower pair by basal nerves, which are small and become lost before 
reaching half the distance to the margin; other nervation coarse, irregu 
lar, and forming large areolae. 
The specimen figured appears to be all that was obtained of this 
species. As may be seen from the drawing, it lacks the apex and much 
of the side. It would seem to be approximately circular in outline, 
being about 5 cm. in length and the same in width. The nervation is 
very prominent, appearing on the stone in strong raised lines. It has 
the palmate nervation, with the smaller basal nerves of the well-known 
ancient type of Populus. 
1 Etudes sur la Veg. d. Sud. Este France, Vol. Ill, p. 158, PI. Ill, fig. 4 (1867). 
2 Ibid., p. 162, PI. II, figs. 6-8; PI. Ill, fig. 1 (1867). 
3 Trans. Roy. Soc. Canada, Vol. VIII, Sec. IV, p. 82 (1890). 
