coon PROCEEDINGS OF THE NATIONAL MUSEUM. A495 
the midrib. In ascending towards the tip of the compound leaf, the 
leaflets become linear in shape and are more closely approximate, until 
are obliquely attached to the midrib. The leaflets of the central part 
of the leaf are longest, giving the elliptical outline. Nerves, three in 
_nunber, strong, parallel with each other and the margins of the leaf- 
lets. 
_ The imprint shows the under side of the leaf uppermost, so that the 
midrib conceals the insertions of the leaflets. Taking as correct Heer’s 
© distinction between Zamites and Pterophyllum,* this imprint does not 
a. positively which of the two it is. It seems, however, to agree 
best with Zamites and may provisionally be put in that genus. In the 
form of its leaflets it is quite near Zamites speciosus Heer,t agreeing 
pretty well with some of the features of the smaller forms of that species, 
but the leaflets are proportionately broader. The basal leaflets also are 
quite different, and the gradation from these into those higher up is 
not seen in Heer’s plant. 
; As stated before, it is somewhat singular that neither Mr. Knowlton 
2 nor Mr. Weed seems to have discovered cycads. This certainly indi- 
z cates that they are not generally distributed in the Great Falls strata, 
_ but are limited to particular horizons. 
UNIVERSITY OF VIRGINIA, 
February 10, 1892. 
PLATE LXXXII. 
ie 
.1. Aspidium montanense, n. sp. Pinnules from the lower part of the frond. 
2. Aspidium montanense, n. sp. Fragments of a fructified compound pinna. 
. 3. Aspidium montanense, n. sp. Detached pinne from the upper part of the 
frond. 
eege 
dee de 
PLATE LXXXIII. 
Fig. 1. Pecopteris montanensis, n. sp. 
Fig. la. Magnified portion of Fig. 1. 
2. Aspidium montanense, n. sp. Normal pinnules. 
Fig. 3. Aspidium montanense, n. sp. Lobed pinnie from the upper part of the frond. 
Fig. 3a. Aspidium montanense, n. sp. Enlarged portion of Fig. 3. 
Fig. 4. Aspidium monocarpum, n. sp. Serrate toothed pinne or pinnules from the 
upper part of the frond. 
Fig. 5. Aspidium monocarpum, n. sp. The termination of a compound pinna. 
Fig. 6. Aspidium monocarpum, n. sp. Pinnules from lower part of the frond. 
Fig. 6a. Aspidium monocarpum, n. sp. Enlarged portion of Fig. 6. 
PLATE LXXXIV. 
SRG GVO PEON 52 PEELE PEI INL SELLE MELLIN I GEA Og MCE 
| 
— 
oS 
ie 
Fig. 1. Aspidium angustipinnatum Font., var. montanense, n. var. 
Fig. la. Enlarged portion of Fig. 1. 
2. Cladophlebis heterophylla, n. sp. 
Fig. 3. Aspidium monocarpum, n. sp. Showing fertile portion of frond. 
Fig. 3a. Enlarged portion of Fig. 3. . 
Fig. 4. Zamites montanensis, n. sp. 
*Flor. foss. arct., vol. 111, p. 62. 
tFlor. foss. arct., vol. 11 Die Kreideflora de arctischen Zone, Pl. xiv, Fig. 11. 
