MEMOIES

CAENEGIE MUSEUM.

Vol. VIII. No. 2.

FOSSIL PLANTS FROM THE BEDS OF VOLCANIC ASH NEAR MIS-
SOULA, WESTERN MONTANA.

By 0. E. Jennings.

(Plates XXII-XXXIII)

Introductory.

This paper deals with some fossil plants obtained by Mr. Earl Douglass from
the beds of volcanic ash in the vicinity of Missoula, Montana, and with a smaller
collection made by him near Winston, Montana. The specimens are now in the
Carnegie Museum.

The fossils from near Missoula were collected bj' Mr. Douglass from two' places.
One of these places is termed on the labels "Locality 165" and is stated to be about
one and one-half miles north of Missoula, the collections having been made Sep-
tember 26-30', 1903. These beds are noted as being "Several hundred feet thick
and are composed of volcanic ash, sandstone, conglomerate, etc. There are several
seams of coal." Another label from the same place says: "In beds of volcanic
ash. Coal above and below." The other station from near Missoula, and from
which the better part of the material came, is evidently near "Locality 165" and is
called on the labels "Locality 196." The collection from Winston was made on
September 23, 1902, on the north side of Beaver Creek, northeast of Winston,
Montana. This latter collection is a small one, containing but two or possibly
three species.

The Missoula collections, with which this paper is mainly concerned, were

385

386 MEMOIRS OF THE CARNEGIE MUSEUM.

taken by Douglass from beds which he beheved to be of Ohgocene age.^ He states
that they "appear in the main to represent the Titanotherium and Oreodon beds
of South Dakota." This horizon, as understood by most American paleontologists,
includes approximately the lower half of the White River formation.^ The
fossil plants in these deposits consist of impressions of leaves and of leafy twigs,
there being also a few impressions of fruits and leafless twigs. The Missoula
specimens are in a very light colored, grayish-white, soft and friable rock, consisting
of a fine-grained volcanic ash, which was evidently more or less stratified and lami-
nated.'-* It is generally believed that the dust was wind-borne and that it was
mainly deposited in freshwater lakes or other shallow basins. Douglass states
that "It does not appear that the water was as a rule very deep. There are un-
doubtedly not only lake but marsh and river deposits. . . . We find nearly every-
where evidences of shallow water, such as ripple marks, bird tracks, plant remains,
shallow water mollusca, etc." Rowe*^ also states his belief that the ash fell in
freshwater lakes.

The Missoula specimens mostly preserve in considerable detail even the finer
venation of the leaf surfaces, and in a number of instances the outline of the whole
leaf is plainly evident. The Winston specimens are, however, in a harder, light
gray rock, which has slickenside surfaces developed at various angles and directions
and presents every appearance of having once been a slumping mass of very fine-
grained mud. In this material the fossils are unsatisfactory, the hardness of the
rock and its irregularity of fracture resulting in fragmentary specimens.

I have undertaken the study of these various collections more as a student of
modern systematic botany and ecology than as a paleobotanist, and it is barely
possible that my conclusions may in some instances differ from what might have
been those of a paleobotanist, trained as a stratigrapher. However, no sharp line
of distinction can now be drawn between the work of a paleobotanist on the one
hand and that of the student of modern botanj'- and ecology on the other, and it is
plainly evident that each of these fields of study may j^et receive many valuable
and enlightening contributions from the other.

In the preparation of the illustrations accompanying this article I have had
the able assistance of my wife, Grace K. Jennings, and to her is due quite largely

■ Douglass, Earl. New Vertebrates from the Montana Territory. Annals Carnegie Museum, II,
1903, 145-199.

^ Willis, Bailey. Index to the Stratigraphy of North America. TJ. S. Geol. Surv., Prof. Paper
LXXI, 1912, p. 770.

=* Rowe, J. P. Some Volcanic Ash Beds of Montana. Univ. Montana Bull., XVII, 1903.

" Op. cit., p. 146.

^ Op. cit., p. 12.

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 387

the excellence of manj'^ of the photographic reproductions. The photographs were
made with an ordinary 5 X 7-inch bellows camera, the specimens being usually
placed in direct sunlight at a low angle of incidence in order to give sharper contrast
and to show better the features of relief on the impressions. The photographs
showing parts of the specimens enlarged were made by supplementing the ordinary
lens of the camera with an enlarging lens which fits over the front of the regular
lens like a cap. To give greater contrast in these enlargements ordinary daylight
was supplemeated with a rather strong desk dissecting lamp fitted with "daylight"
glass and by proper manipulation of this light the inequalities on the surface of the
leaf impressions were shown as highlight and shadow.

In the publication just referred to Rowe gives a short list of the plants collected
from beds of volcanic ash near Missoula, the list being as follows:

1. Sequoia Langsdorfii. 6. Cornus or Viburnum.

2. Sequoia, probably new species. 7. Populus balsamoides (?)

3. Glyptostrobus europceus. 8. Fruit near Chinchonidium.

4. Alnus. 9. Taxodium occidentalis.

5. Carpinus, probably new species. 10. Taxodium.

Accompanying Rowe's report are three plates illustrating some of the fossil
plants from these beds. Plants shown on these plates are evidently the same as
some of those described in the present paper, as follows: Plate VI shows at the
left upper margin what is probably a piece of a leaf of Alnus Hollandiana Jennings,
a specimen of Populus Zaddachi Heer being shown in the middle of the plate,
while both Plates VI and VII show leaves of what I have described as a new species,
Betula multinervis. The Taxodium-\ike sprays in Plate VIII are evidently the same
as the sprays in our material which I believe to represent one of the various types of
Sequoia Haydenii (Lesquereux) Cockerell.

The Glyptostrobus mentioned in Rowe's list is probably the same as the speci-
mens in our collections which I believe belong to Sequoia Haydenii. The Carpinus
is evidently the same as my Betula multinervis; the Populus balsamoides (?) I take
to be Populus Zaddachi Heer and the Taxodium, like that shown in his Plate VIII,
at least, is probably Sequoia Haydenii.

II. Relations of the Fossil Flora from Missoula to the Nearest Eocene
AND Miocene Floras of the West.

The specimens collected by Mr. Douglass from near Winston appear to repre-
sent but two, or possibly three, species, as follows :

388 MEMOIRS OP THE CARNEGIE MUSEUM.

Equisetum insculptutn Jennings
Equisetum sp. Vegetative buds
Aralia longipetiolata Jennings

These species appear not to be represented in collections described from other
localities and this fact, in connection with the wide geological ranges of the genera
Equisetum and Aralia, makes the collection of little value as a means of correlating
this flora with other ancient floras.

The specimens from the Missoula district represent at least twenty species,
ten of which I have described as new and one of which requires a new name. These
twenty-one species are enumerated in the following list, the numbers in parentheses
indicating from which of Douglass' localities the specimens came :

Sequoia Haydenii (Lesquereux) CockereU. (165, 196)

Sequoia oblongifolia Jennings. (196)

Thuy apsis gracilis Heer. (196)

Sabina lingucefolia (Lesquereux) CockereU. (196)

Typha Lesquereuxii CockereU. (196)

Cyperacites sp. (196)

Populus smilacifolia Newberry. (165)

Populus Zaddachi Heer. (165, 196)

Juglans pentagona Jennings. (165)

Betula multinervis Jennings. (165, 196)

Alnus microdontoides Jennings. (165, 196)

Alnus Hollandiana Jennings. (196)

Quercus approximata Jennings. (196)

Quercus fiexuosa 'Newberry. (165)

Quercus laurisimulans Jennings. (196)

Ficus (?) prunifolia Jennings. (196)

Ilex furcinervis Jennings. (196)

Celastrus parvifolius Jennings. (196)

Acer oregonianum Knowlton. (165)

Vaccinium palmocorymbosum Jennings. (196)

The flora represented in the Missoula collections appears closely related to
that reported for the Florissant basin of Colorado." Of the fifteen genera repre-

* Among the more important titles consulted with reference to the Florissant flora were the following:
Kirchner. Trans. St. Louis Acad. Sci., VIII, 1S98, pp. 161-198, Pis. 11-15.
CockereU. Univ. Colorado Studies, III, No. 3, 1906, 1.57-176. Bull. Am. Mus. Nat. Hist.,

XXIV, 1908, pp. 71-110, Pis. 6-10. Amer. Nat., XLIV, 1910, pp. 31-47.
Knowlton. Proc. U. S. Nat. Mus., LI, 1916, pp . 241-297, Pis. 12-27.

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 389

sented in the Missoula flora all but two are also represented in the Florissant.
Three species, Sequoia Haydenii, Typha Lesquereuxii, and Sabina lingucefolia,
apparently occur in both floras and there are other species which a further study of
more complete and more abundant material might prove to be identical. Further
comparisons show that to a large extent the genera having more than one species
each in the two floras were largely the same. In the Missoula flora Sequoia,
Populus, Alnus, and Quercus were each represented by more than one species..

One of the fossils in the Missoula collection apparently represents the species
described by Knowlton from the Mascall beds of the John Day Basin, Oregon, and
in a number of respects the Missoula flora seems to be rather closely allied to the
Mascall flora. Eleven of the Missoula genera occur in the Mascall and, while,
with the exception of the maple, perhaps none of the corresponding forms in the
two floras are identical, some of them are rather closely similar. Of the genera
reported as having two or more species each, the Mascall flora has Sequoia (with
2 or 3), Quercus (5 or 6), Celastrus (2), and Acer (8), as against Sequoia (2), Populus
(2), Alnus (2), and Quercus (3) in the fossil flora at Missoula.

Another of the floras of the John Day Basin reported by Knowlton^ aad of
interest with reference to the Missoula collections is that from what are regarded as
upper Eocene^ beds at Bridge Creek, Oregon. Comparing the Missoula flora with
that of Bridge Creek it aiDpears that seven of the fifteen genera of the former are
represented also in the latter. Of the genera of the Bridge Creek flora represented
by more than one species there are Sequoia (with 2 species), Juglans (3), Betula (4),
Alnus (4), Quercus (8), Ficus (1), Acer (1). The Missoula flora has Sequoia (2),
Populus (2), Alnus (2), and Quercus (3), so that, considering the relative percentage
of species represented by the leading genera together with the number of genera
common to the two floras, it would appear that the flora from Missoula is about as
closely related to the Bridge Creek flora as to that of the Mascall beds.

Knowlton" has reported eighteen genera of plants among the fossils collected
in the Payette formation (regarded by Knowlton as Upper Eocene)^" from the

' Knowlton. Fossil Flora of the John Day Basin. U. S. Geol. Surv. Bull., CCIV, 1902, pp. 19,
89-93, 106-108, 113. Op. cit, pp. 17, 89-93, 103-105, 113.

* Merriam, J. C. Significant Features in the History of Life on the Pacific Coast, in Nature and
Science on the Pacific Coast, 1915, pp. 88-103. See also A Contribution to the Geology of the John Day
Basin. Bull. Dept. Geol., Univ. Cal., II, 1901, 269-314, 285-287, 290-299; also Merriam, J. C, and
Sinclair, W. J. Tertiary Faunas of the John Day Basin. Bull. Dept. Geol, Univ. Cal., V, 1907, p. 173.

s Knowlton. The Fossil Plants of the Payette Formation. U. S. Geol. Surv. Ann. Rpt., XVIII,
Part III, 1898, pp. 721-736, Pis. 99-102.

'° Knowlton. Succession and Range of Mesozoic and Tertiary Floras, in Willis and Salisbury,
Outlines of Geologic History, Chapter X, 1910, pp. 200-211.

390

MEMOIRS OF THE CARNEGIE MUSEUM.

fossil lake beds of the Snake River in western Idaho. Eight of these genera are
common to the Payette and Missoula collections. Of the Payette genera five are
represented by more than one species each (Sequoia, Myrica, Populus, Betula, and
Quercus) as against fom' such genera in the Missoula collections (Sequoia, Populus,
Alnus, and Quercus). While not identical in the two floras a number of species
are here also represented by similar forms.

The Lamar flora described by Knowlton^^ from the Yellowstone National Park
has listed for its lower member ("Fossil forest a") eight of the fifteen genera which
I have recognized in the Missoula collections, and there are at least five or six
species closely similar in these two floras.

From what he regards as the true Green River formation "excluding Florissant
and Elko Station," CockerelP^ has compiled a fist of the plant genera represented.
A comparison of this list with the list of Missoula genera shows nine genera to be
common to the two floras.

The following table presents in a more compact form a list of the plant genera
represented in the Missoula collections together with the occurrences of the genera
in the other floras discussed in the preceding pages :

Table of the Genera Represented in the Collections of Fossil Plants from the Beds of Vol-
canic Ash near Missoula, Montana, showing also the Occurrence of these Genera in a
Number of other Fossil Floras.

Regarded as Upper Eocene.

Middle Miocene.

White River.
Missoula, Mont.

Lamar.

Yellowstone

National Park.

Green River.

Wyoming and

Utah.

Payette.
Snake River,
West Idaho.

Bridge Creek.
Oregon.

Mascall.
Oregon.

Florissant.
Colorado.

Sequoia

Thuijopsis. . . .

Sabina

Typha

Cyperacites . . .

Populus

Juglans

Betula

Alnus

Quercus

Ficus

Ilex

X

X
X
X

X
X

X
X

X

X
X

X

X
X
X
X

X

X

X
X
X

X
X

X

X

X

X
X
X
X
X

X

X

(x)

X
X
X
X
X
X
X

X
X

X

X
X

X
X
X
X
X
X
X

Celastrus

Acer

X
X

Vaccinium . . .

X

" Knowlton. Fossil Flora of the Yellowstone National Park. U. S. Geol. Surv., Monograph
XXXII, Part II, Chapter XIV, 1899, pp. 651-791.

i^Cockerell. The Fossil Flora of Florissant, Colorado. Bull. Amer. Mus. Nat. Hist., XXIV,
1908, p. 44.

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 391

It is obviously unsafe in questions of comparison or correlation between,
rather closely related floras to place much reliance on such evidence as may be
furnished by a small collection of fossil plants consisting mainly of leaf -impressions.
Conditions of deposition and fossihzation are probably very rarely effective in
preserving a representative sample of a flora, unless the fossils collected are in
large numbers. As far as the indications go, it appears that the Missoula specimens
represent much the same kind of a flora as was preserved in the Florissant beds.
Yet differences between the Missoula flora and the Green River flora, as referred to
above, and generally regarded as Upper Eocene^^ in age, is by no means great.
The Florissant beds are now regarded as Miocene^*, Cockerell even advancing both
the Mascall and Florissant floras to middle Miocene. ^^

As far as the genera are concerned collectively there has been comparatively
little change in the flora of the temperate regions of the United States since Floris-
sant times, and, allowing for a probably gradual cooling and a decrease in moisture
during the period between the Green River (Eocene) and the Florissant (Middle
Miocene), it appears that the changes in genera in this latter period were Ukewise
not great. Cockerell, comparing the Intermediate and Lamar floras on the one
hand and the plants "said to occur elsewhere or in the Eocene" on the other, shows
that these Yellowstone floras have "twenty-six plants specifically identical with
those of the basal Eocene" and, further, "The conclusion seems to be legitimate
that the Yellowstone Intermediate and Lamar florse are Upper Eocene, or at least
older than Miocene." In his discussion of the records furnished by fossils as to
the distribution of the various floras through the different periods of time,. Clements
says^'' that " the flora of the Oligocene was essentially that of the Eocene somewhat
reduced by deformation, and the plants of the Pliocene are practically those of the
Miocene, but with a striking reduction," the reduction mentioned being due in
part to the reduction in the area in which sedimentation and fossihzation were
taking place.

Of the floras referred to in the above discussion and in the table, the Bridge
Creek, Lamar, Payette, and Green River are now probably best regarded as late

" Willis. Index to the Stratigraphy of North America. U. S. Geol. Surv., Prof. Paper LXXI,
1912, pp. 676, 758-760, 765.

" Knowlton. A Review of the Fossil Plants in the United States National Museum from the
Florissant Lake Beds of Florissant, Colorado, With Descriptions of New Species and Lists of Type
Specimens. Proc. U. S. Nat. Mus., LI, 1916, pp. 241-297, Pis. 12-27.

'=■ Cockerell. The Miocene Trees of the Rocky Mountains. Am. Nat., XLIV, 1910, pp. 31-47;
Some American Fossil Insects. Proc. U. S. Nat. Mus., LI, 1916, pp. 81-106.

" Clements, F. E. Plant Succession. Carnegie Inst. Wash., Publ. CCXLII, 1916, p. 352.

392 MEMOIRS OF THE CARNEGIE MUSEUM.

.Eocene, the Mascall and Florissant as middle Miocene. Assuming this to be the
case it is interesting to group together the four upper Eocene floras for purposes
of comparison with the two Miocene floras. Upon doing this it appears that of
the fifteen genera in our Missoula flora twelve occur also in the combined upper
Eocene floras and fourteen in the combined middle Miocene floras. This compari-
son does not show any great preponderance in favor of the Miocene, and it is
quite possible that climatic and other ecological conditions may have brought
about similar groupings in the Missoula and Florissant floras somewhat out of
proportion to the actual systematic relationships of the floras existing at the time
these fossils were formed.

The Missoula flora probably occupied the shores and surrounding slopes of a
high mountain lake. Douglass says, however: "There is doubt that the mountains
were as high during the White River epoch as at the present time."" Cockerell
and other writers have referred to Lake Florissant as a mountain lake and some of
the differences between the Mascall and Florissant floras are thought by Cockerell
to be possibly due to the differences between a lowland flora, like that of the MascaU,
and one around a mountain lake, such as that of the Florissant.^* I am inclined
to believe that the similarity of habitat has brought about a similarity in the fossil
floras from Missoula and Florissant that may have obscured to a considerable degree
the actual difference of the two floras in point of time.

Two of the plants represented in the Missoula collections {Thuyopsis gracilis
Heer, and Populus Zaddachi Heer) appear to be the species described and reported
by Heer from the Atane beds of Greenland. These beds were regarded by Heer^^
and some other authors-" as Miocene, but they are more likely Cretaceous or early
Eocene.-^-" A considerable number of plants described from the arctic regions by
Heer and others from beds thought at that time to be Miocene appear farther south
during early and middle Tertiary times. This southward shifting of floral zones is
to be ascribed to corresponding climatic changes. Clements notes-^ that 'A
distinct cooling is indicated by the flora of the early Eocene, and the usual accom-

'' Douglass. New Vertebrates from the Montana Territory. Annals Carnegie Museum, II,
1903, p. 149.

1* Cockerell. The Miocene Trees of the Rocky Mountains. Am. Nat., XLIV, 1910, p. 37.

'" Heer, 0. Flora Fossilis Arctica I, 1S6S, pp. 98-99, and various other pages in this and other
volumes of the series.

-" Schuchert, C. Climates of Geologic Time. In Huntington's The Climatic Factor. Carnegie
Inst. Wash., Publ. CXCII, 265. 1914.

21 Willis, Bailey. Index to the Stratigraphy of North America. U. S. Geol. Surv., Prof. Paper
LXXI, 1912, pp. 705 and 838.

'- Clements, F. E. Plant Succession. Carnegie Inst. Wash., Publ. CCXLII, 1916, p. 242.

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 393

paniment of aridity is shown by the salt and gypsum beds of the Texas formations
of the period. The earliest Eocene flora, that described by Heer from Belgium,
indicates a temperate climate, characterized by Quercus, Castanea, Salix, Laurus,
Hedera, etc. Similar horizons are found in the lower Eocene of France and England.
At a later stage, palms, bananas, figs, cinnamons, etc., became dominant, indicating
a return to tropical conditions.' With the period of "mountain making and vul-
canism" in the Oligocene there came another change to a cooler and drier climate. ^^
Clements further notes-'* that the evidence indicates "that the Oligo-Miocene cycle
was marked by a general chmate cooler and drier than that of the Eocene, and hence
by a differentiation of chmates approaching that of today. " And, further, " So far as
dominants are concerned there appears to be little difference between the floras of
the Eocene and Miocene. The dominant tree genera appear to have been about
equally represented in both, and this is largely true of shrubs. . . . Thus, while
the flora remained largely the same, it must have undergone marked differentiation
and shifting as a result of the deformation and cooling which initiated the cycle.
The northerly climax zones must have been broadened as well as pushed to the
south. . . . Before the chmatic effect of Oligocene deformation had disappeared
the deformation cycle of late Miocene and Pliocene had begun to culminate in the
Ice Age. Thus the shifting of the climatic zones took place only to the southward,
as well as downwards on the mountains." The cooling during the Oligo-Miocene
cycle "from a tropical or subtropical climate to a warm temperate one over much of
the continent was permanent."

Assuming, then, that during the period from the late Eocene up into the
Miocene there was, in general, a cooling and drying of the climate and a differentia-
tion of climatic regions and zones and, further, that during this time there was a
migration of northern plants southwards as well as down from the higher and
cooler habitats to the lowlands, it seems to me not unreasonable to beheve that the
mountains of western Montana during the Oligocene would have been populated by
the northern flora long before a similar region in central Colorado at a latitude of
about six hundred miles farther south. The Missoula region would likely have
been invaded by this northern flora long before the Mascall region Ijdng to the
southwest in Oregon and probably on lowlands separated but little from the western
ocean either by distance or elevation. Unless exception might be made in the case
of the Payette flora, I feel fairly certain that the Florissant was the only one of the
fossil floras discussed which approximated very closely the Missoula flora as to the

^' Schuchert. Op. cit.

-' Clements. Op. cit, pp. 364-366.

394 MEMOIRS OF THE CARNEGIE MUSEUM.

ecological conditions involved. I think that the similarity of the Missoula and
Florissant floras may actually be regarded as indicating a considerable time interval
during which similar stages in a southward migration of northern plants were
reached in the two floras. During the corresponding disappearance of the southern
plants the Missoula region would, of course, lose them before they would disappear
from the Florissant and, in this connection it is interesting to note that of the
southern element Florissant had Sapindus, Diospyros, Persea, Leuccena, Annona,
Ficus, and others, while only one such species, which I doubtfully determined as
Ficus, appears in the Missoula collection. All this leads me to believe that the
collections from Missoula represent an earlier period than do the Florissant collec-
tions, a period somewhere between the late Eocene and middle Miocene, and T
see no reasons for not accepting Douglass' claim that the beds belong to the White
River formation and are of Oligocene age.

If we may accept the claim that there had come about a differentiatioQ of
climates it would not be unreasonable to expect a considerable difference between
the flora of the Missoula White River and the Oligocene flora of the lower south-
eastern part of the United States, much as is the case today with the modern floras.
Berry has this to say with reference to the tropical character of the Oligocene flora
of the Catahoula sandstone of the Gulf Coastal Plain^^: "Finally, the facies of the
flora as a whole is that of the abundant floras found in the early Oligocene of
southern Europe, notably in Provence, France, in Tryol, and in Dalmatia and
Styria. Not only does it exhibit this parallelism with these European early Oli-
gocene floras, but when the genera are considered separately it appears that almost
without exception they have not been found in what are now temperate latitudes
in any beds younger than Oligocene." In general this was a tropical flora and the
climate along the Gulf Coast at that time was evidently much more tropical than
now.-"--' There was later a general cooling, possibly also a shifting of ocean currents
bringing about a change from subtropical to cold-water conditions, with evidently
somewhat corresponding changes in the flora of the adjacent coasts. Berry has
shown by a study of the flora of the Calvert formation from Virginia and the Dis-
trict of Columbia that by the time of the middle Miocene the climate in this region

" Berry, E. W. The Flora of the Catahoula Sandstone. U. S. Geol. Surv., Prof. Paper XCVIII-M,
1916, pp. 227-243, Pis. 55-60.

'^^ Berry, E. W. A Study of the Tertiary Floras of the Atlantic and Gulf Coastal Plain. Proc.
Amer. Phil. Soc, L, 1911, 311-315.

" Dall, W. H. Contributions to the Tertiary Fauna of Florida, Part VI. Trans. Wagner Free
Inst., Ill, 1903, p. 1594.

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 395

was cooler, probably only warm-temperate.-^ "The Calvert flora was a coastal
flora of strikingly warm-temperate affinities, comparable with the existing coastal
floras of South Carolina and Georgia along the south Atlantic coast or with those
along the coast of the Gulf of Mexico from western Florida to eastern Texas.
The climate of the Chesapeake Miocene epoch, cooler undoubtedly than that of
the Apalachicola or preceding epochs, was neither cold nor cool temperate."

It is evident that the Oligocene and middle Miocene floras of the middle and
southeastern Atlantic Coastal Plains were related ecologically, and, especially as to
the climatic aspect, were related to the Oligocene and middle Miocene floras of the
West in very much the same manner as are the modern floras of those regions.
I can see nothing in either the character or ecological relationships of the old south-
eastern floras that might serve as an argument against our belief in the Oligocene
age of the Missoula flora.

III. Ecological Conditions Indicated by the Fossil Flora from Missoula.
As to the ecological relationships of the flora around the old Missoula basin,
it is interesting to compare the fossil flora with that, which in the case of a shower of
volcanic ash we might suppose would be represented by plant materials imbedded
under conditions hkely to lead to fossil izati on in the basins of some of the lakes
now to be found in western Montana and Idaho. The plants preserved in the
Missoula fossil collections were practically all woody plants, evidently mostly trees,
and I have found particularly useful for the purposes of this comparison the biologi-
cal reconnoissances of Flathead Lake and several other smaller lakes in western
Montana by Elrod,^^ and the more detailed studies of the forests of the Flathead
Valley by Whitford.^" To a considerable extent, also, I have relied upon first-
hand information gained during two weeks in the summer of 1915 which my wife
and I spent in botanizing around Lake Newman, along the Washington-Idaho
state boundary line about one hundred and sixty miles west of Missoula.

Whitford's classification of the vegetation in the Flathead Valley, western
Montana, in the midst of rugged mountains, shows it to consist of five main divi-
sions, as follows: I. Meadow (hydrophytic) ; II. Englemann Spruce Forest (meso-
n's Berry, E. W., Physical Conditions indicated by the Flora of the the Calvert Formation. U. S.
Geol. Surv., Prof. Paper XCVIII-F, 1916, p. 66.

" Elrod, M. J. A Biological Reconnoissance in the Vicinity of Flathead Lake. Univ. Mont. Bull.,
X, 1902, pp. 91-182, Pis. 18-46. (Biological Series III.)

™ Whitford, H. N. The Forests of the Flathead Valley, Montana. Bot. Gaz., XXXIX, 1905,
pp. 99-122, 194-218, 276-296.

396 MEMOIRS OF THE CARNEGIE MUSEUM.

hydrophytic) ; III. Western Larch — Douglas Spruce Forest (mesophytic) ; IV.
Douglas Spruce— Bull Pine Forest (meso-xerophytic) ; and V. Prairie (xerophytic).

Numbers I, II, III, and V of Whitford's divisions contain more or less abun-
dantly species corresponding to those represented in the Ohgocene flora of Missoula.
The Meadow (I) is usually along the end or border of a lake or else in a wet swampy
depression, and such a meadow with subsequent fiUing or draining will tend to be
invaded and eventually succeeded by Spruce Forest (II).

From the articles cited I gain that most of the meadows have, on the hummocks
or as a bordering thicket, the advance guard of the spruce forest in the form of
willows (Salix) and alders (Alnus). The thickets formed by these plants are
eventually entered by spruce {Picea Engelmanni) accompanied by poplars (Populus
angustifolia and P. tremuloides) , birches {Betula papyrifera) , and sometimes
Echinopanax homdum, Rhamnus alnifolia, and Cornus stolonifera. For the pur-
poses of the present discussion, the wet meadow and spruce forest will be treated
as one unit. They are both situated close to the water or are in the central part of
a wet depression and, often the shore of the lake may be so dry that there is no
meadow, the spruce forest bordering the shore directly, with perhaps but a narrow
fringe of alders, willows, and a few other plants.

Three of the genera mentioned in the above paragraph were present also in
the Ohgocene flora of Missoula, these three genera including five of the fossil species.
Added to these five, should be the fossil species of Typha, Cyperadtes, Vaccinium,
and Ficus, which must have occupied either the wet meadow, its invading and
surrounding thickets, or the adjacent wet woods. Thus considered, the meadow or
its immediate borders or adjacent wet woods in the Flathead Valley would be quite
Ukely to contribute to the waters of the nearby lake leaves of representatives of at
least five of the genera found in the Ohgocene fossil flora from Missoula, while,
considered from the standpoint of systematic and ecological equivalents, similar
habitats around a lake in the Missoula district in Ohgocene times might easily have
contributed at least nine of the twenty-one species found among the Missoula
fossils.

Whitford's third class, the one having the habitat next drier than the spruce
forest and thus usually the one next higher on the slope from the lake basin, is the
Western Larch-Douglas Spruce forest. Characterizing this forest are the larch
{Larix occidentalis) , Douglas Spruce {Pseudotsuga mucronata), and accompanying
them are the Lodge-pole Pine {Pinus Murrayana), Lowland Fir (Abies grandis),
White Pine (Pinus monticola), Engelmann Spruce {Picea Engelmanni), White Cedar
{Thxiya plicata), and occasionally Abies lasiocarpa, Pinus pondcrosa, Tsuga hetero-
phylla, and some other chieflj^ deciduous trees and shrubs.

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 397

With gentle slopes rising from the lake basins this forest will usually be found
at some little distance from the open water, but on higher, drier, well-drained soil
on steeper slopes or benches along the lake shore, such forests occur close to the
open water. At Newman Lake near the Idaho-Washington boundary line patches
of this association occupy soil not over fifteen feet from open water and extending
down upon levels not over three feet above lake-level. Such a forest might easily
become a strong competitor with the meadow-spruce forest in contributing leaves
and other materials to a bed of volcanic dust accumulating in the lake close by.
The old ecological equivalent of this habitat probably furnished for fossilization
in the Oligocene lake-bed at Missoula the two species of Sequoia, the Thuyopsis
(represented in our Northwest now by Thuya), the maple (Acer), the walnut
(Juglans) , and perhaps some of the oaks (Quercus) .

On sandy or rocky habitats or on dry uplands and slopes, where not too cold,
the next drier habitat to that occupied by the Larch-Douglas Spruce forest is that
of the Douglas Spruce-Bull Pine forest. On rocky or dry sandy soils around New-
man Lake this forest comes down practically to the water's edge. Whitford^^"" notes
that: "If the outcrop is near a large body of water like Flathead Lake, Juniperus
scopulorum is one of the first trees." The forest is mainly composed of the Yellow
Pine or Bull Pine (Pinus ponderosa) and Douglas Spruce. Such a forest around an
OUgocene lake-basin at Missoula could thus have contributed readily from a
rocky cliff or promontory twigs of the Juniper (Sabina) or with the somewhat
warmer conditions indicated by the presence of the oaks and possibly a fig, the
Juniper might have come from a sandy shore or from sand dunes such as are now so
characteristically covered with the Red Cedar {Juniperus virginiana) along the
shores of Lake Erie and the lower end of Lake Michigan.

Assuming that the climate in the Oligocene lake basin at Missoula was warmer
and probably drier (see p. 394) than that now prevailing in the Flathead Valley, it
appears probable that the habitat occupied by the Oligocene equivalent of the
Douglas Spruce-Bull Pine forest occupied a larger area, or at least crowded more
closely the more moist areas around the basin. I believe that this habitat is the
one which probably furnished the oaks, or at least most of them, and possibly also
the Holly (Ilex) and Celastrus, although modern species of both of these genera
also occur in more moist habitats. The Oligocene oaks were apparently xerophytic,
as indicated by the nature of the leaf impressions, and I take them to have been
comparable to the modern live-oaks, chestnut-oaks, and shingle-oaks so character-
istic of moderately xerophytic habitats in the eastern, southeastern, and south-
western parts of the United States.

3"" Op. ciY., p. 216.

398 MEMOIRS OF THE CARNEGIE MUSEUM.

As indicated in the preceding discussion, the fossils in the volcanic beds at
Missoula might readily have been contributed to the waters of an Oligocene lake,
in a climate somewhat warmer than now prevails in that region, by a series of
vegetational associations ranging from wet meadow to moderately xerophytic
oak-forests on rocky or sandy shores, all of these vegetational associations in close
proximity, at least here and there, to the waters of the lake.

IV. Remarks on the Fossil Flora from Winston, Montana

The collections from the consolidated mud from Winston apparently belong
to the same general age as the Missoula collections. As noted earlier in this paper-
there are but two species represented, a small Equisetum and a plant which I have
referred to Aralia. Neither of these plants offer much basis for correlation with
other fossil floras. Equisetum occurs in all of the late Eocene and middle Miocene
floras listed in the preceding table, excepting only Bridge Creek, and it, or the forms
referred to Equisetites, range from the Paleozoic up to modern times, so that its
presence means little as to the time relations of the beds in which it occurs. Aralia
occurs in the Lamar and Green River floras (late Eocene) and in the Florissant
(middle Miocene). Its range from the upper part of the lower Cretaceous up to
modern times makes it, too, of little use for jDurposes of correlation. If there is
other evidence, as for instance, from animal fossils, for believing that these plants
were of Oligocene age I can see no objection to such a view from any evidence to be
furnished by the plant fossils. Ecologically the Equisetum and Aralia might readily
have been a part of the vegetation believed to have grown around the Oligocene
lake at Missoula; the Equisetum in shallow water with sandy bottom, the Aralia
in the thickets invading the wet meadow or in the moist woods.

V. Descriptions of the Species in the Oligocene Flora of Missoula,

Montana, and of a few Species from Winston, Montana.

1. Equisetum insculptum Jennings, sp. nov. (Plate XXII, Fig. 2.)

The specimen consists of a mould of a piece of stem about 3 cm. long, this
mould being mainly filled with the corresponding cast. The mould and cast repro-
duce in great detail the minute features of the outside of the stem. The stem was
about 3 mm. in diameter but was compressed in fossilization to about 4 mm. and
it had eighteen ridges about 0.5 mm. apart, these being quite prominent and each
having two distinct rows of papilla-like tubercles. In the rather deep and rounded
furrows there are fine but distinct and closely set silex ridges running crosswise and

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 399

there are longitudinal lines indicating the position of two rows of stomata. The
character of the impression suggests a species with a rather firm and strong stem-
wall, such as is the case in the living Equisetum hyemale Linnaeus.

The one specimen upon which this record is based comes from "Locality 139,"
near Winston. So far as I have been able to discover among the r-^-;s^^ri™s^
various publications relating to fossil Equisetacece, there have been ^^^^^^,
no fossil species described in which the markings have been so ^^g^^^M
beautifully preserved as in this specimen. The most nearly related ^^^^W$

species are, perhaps, Equisetum wyomingense, described by Les- ^^'^- ^- -^s^^se-

lu7n insculptum

quereux from the Green River group of Wyoming, and the Equise- Jennings. Sketch

turn studied by Knowlton from the Payette of Idaho, both prob- to show details of

ablyEoceneinage. Among living species, ^^gm'seiwmt^an'egra^Mmvar. ^^^^ shown in

Jesupi A. A. Eaton, which is probably a hybrid between E. variegatum Plate xxii, fig. 2.

and E. hyemale^^ is very closely similar, having the double row of ca- ^ " ^^&e a ou

'^ ./ .^ I o fifteen diameters.

rinal tubercles, small stem, and cross-bands of silex in the furrows.

The genus Equisetum, or Equisetites, as most of its older representatives have
been called, is recorded from at least as far back as the Paleozoic. Excepting
possibly for a considerable diminution in size, these plants have changed but little
up to the present time and the various species are of relatively little stratigraphic
value.

As the Winston species seems not to be the same as any of the species before
described, I am designating it as new, the specific name insculptum being used for
it on account of the unusually distinct and bold markings on the outer surface of
the stem.

2. Equisetum sp. (Plate XXII, Fig. 1.)

This is a poorly preserved specimen from the Winston locality representing a
piece of a stem, about 17 mm. long and 3 mm. wide, at the apex of which is indicated
a cluster of three branches, only two of which are preserved with any degree of
distinctness. The most perfect of the branches consists of a short stem about 1 mm.
in diameter and 11 mm. long. This probably is a bud from the basal part of a
plant, just as may be found on some of the Equisetums of today, and such as have
been described several times in paleobotanical literature.

The specimen may represent a plant of the species to which I have given the
name Equisetum insculptum, found at the same place, but aside from a probable
similarity in size and the mere fact that they were taken from the same locality there
is no basis for such an assumption.

^' Holden, Ruth. The Anatomy of a Hybrid Equisetum. Am. Journ. Bot., II, 1915, pp. 225-237.

400 MEMOIRS OP THE CARNEGIE MUSEUM.

3. Sequoia oblongifolia Jennings, sp. nov. (Plate XXIII, Figs. 1 and la.)
Among the various fossils representing Sequoia in the White River material from
Douglass' "Locahty 196", near Missoula, Montana, there are three specimens show-
ing fragments of leafy twigs, which can not be satisfactorily referred to any of the
various kinds of leafy twigs of Sequoia Haydenii, but apparently resemble rather
closely the specimens from Greenland described and figured by Heer as Sequoia
brevifolia, as follows:^-" S. foliis oblongis, basi angustatis, adnato decurrentibus,
confertis, patentibus, planis, distichis, apice obtusis, infimis squamasformibus,
adpressis."

As shown by Heer's figures and later by Lesquereux'^ and by Knowlton,'**
the leaves of the White River plant were more strictly oblong, with straight sides,
and the base more abruptly rounded, while the leaf -blades were about one-half longer
and wider. The White River specimens show the leaves about 7-10 mm. long
by 2-2.8 mm. wide, oblong, the apex rounded and apiculate. The midrib is fairly
strong, there being also faint furrows on each side of it and there are also faint indi-
cations of numerous fine longitudinal striae. The leaves were evidently quite thick
and stiff and the impressions show irregular cross-furrows and ridges, such as are
evident in dried specimens of many living species of Sequoia, Taxus, Podocarpus,
etc., having thick leaves. The base of the leaf is strongly decurrent, while the
leaves apparently spread distichously and at a wide angle, the blade often curving
enough to place the apex of the leaf at almost a right angle with the branch.

In general outline the leaves resemble some of the fossils described as Tazites
and Taxodiiim, but the quite strongly decurrent leaf base would appear to relate
it to Sequoia. It is also similar, possibly very close to some of the specimens referred
bj^ some authors to Sequoia Langsdorfii, but I have preferred to refer the Missoula
specimens to a distinct species on account of the more decidedly oblong leaves
with the apex blunter than seems to be the case in S. Langsdorfii.

4. Sequoia Haydenii (Lesquereux) Cockerell. (Plate XXIII, Figs. 3, 4, 6; Plate
XXIV, Figs. 1, 2, 3; and Plate XXII, Figs. 3, 3a, 4, and 5.)

Hypnum Haydenii Lesquereux, Bull. U. S. Geol. and Geogr. Surv. Terr., I, 1875,
p. 383; Rept. U. S. Geol. Surv. Terr., VII, 1878, p. 44, PL 5, figs. 14, Ub.

52 Heer. Flora Fossilis Arctica, I, 1868, pp. 92 and 93, PI. 2, figs. 2.3 and 23h.
'' Le.squereux, Tertiary Flora, U. S. Geol. Surv. Terr., VII, 1878, p. 78, PL 61, figs. 25-27.
'" Knowlton. Flora of the Montana Formation. U. S. Geol. Surv., Bull. CLXIII, 1900, p. 27,
PL 4, figs. 1-4.

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 401

Sequoia affinis Lesquereux, U. S. Geol. and Geogr. Surv. Terr., Bull. I, 1875,

p. 384 (1876); Tertiary Flora, Rept. U. S. Geol. Surv. Terr., VII, 1878, p. 75,

PL 7; figs. 3-5 and PL 65, figs. 1-4.
Glyptostrobus Ungerif Heer. Lesquereux, Cretaceous and Tertiary Floras,

Rept. U. S. Geol. Surv. Terr., VIII, 1883, p. 139, PL XXII, figs. l-6a.
Sequoia Haydenii (Lesquereux) Cockerell, Science, XXVI, 1907, p. 447; Pop.

Sci. Monthly, LXXIII, 1908, p. 122, text-fig.; Bull. Amer. Mus. Nat. Hist.,

XXIV, 1908, p. 78; Amer. Nat. XLIV, 1910, p. 32, fig. 3, p. 36.

The most abundant conifer in the material studied is a Sequoia which seems
to present a remarkable amount of variation in both size and form of leaf. After
much study I have decided to pursue the course adopted by Cockerell and Knowlton
with respect to the similar series of Sequoias found in the Florissant beds and to
regard these all as belonging to the plant described by Lesquereux as Sequoia
affinis and Hypnum Haydenii.

One common type of twig among these specimens is small and densely leafy,
the largest of this type (Plate XXII, figs. 3 and 3a) being about 7 cm. long, irregu-
larly pinnately branched, the leaves being mainly lanceolate or elliptic-oval,
ranging up to a size of about 3 to 4 mm. long by 1 mm. wide, tapering into a decur-
rent base about half as wide, and tapering above into an acute or somewhat obtuse
apex. The midrib is not prominent, often not showing at all. The leaves spread
at an angle of about 45°, being mostly somewhat recurved and being quite uniform
in size throughout the length of the twigs. These specimens match quite closely
the descriptions and figures of Sequoia Couttsice Heer,^^ but the leaves from the
Montana collections are scarcely or not at all falcate and they are more spreading
than the Bovey Tracy specimens, as shown by Heer's plates. Twigs of this type
are represented in material from Douglass' "Locality 196 " at Missoula, but not from
Winston. This is evidently also the same plant as that occurring in some of the
Tertiary rocks of the Western United States and referred in the past to Glyptostrobus
europceus.

In association with the leafy twigs, but not attached to them, is a short twig
(Plate XXIII, fig. 4) at the apex of which are three cones, at least one of which,
and probably all three, belong to the twig. The cones are oblong, about 6 mm.
thick by 8 mm. long, rounded at the ends, the scales being 3-4 mm. long, with their
shank 4-angled, or perhaps some of them 3-angled, widening to about one and
one-half mm. at the apex, where they are capped by a thin flattened shield about

35 Heer. Fossil Flora of Bovey Tracy, Trans. Royal Soc. London, CLII, 1862, pp. 1051-1055,
PI. 59, figs. 1-19, PL 60, figs. 1-45, and PI. 61.

402 MEMOIRS OF THE CARNEGIE MUSEUM.

2-2.5 mm. wide. The scales are loosely placed on the axis of the cone, the peltate
tops being only rarelj^ in contact with each other and they are little or not at all
mucronate. These cones agree fairly well with the figures given by Saporta^" for
Sequoia Couttsice, but, as was also the case in the comparison of them with the figures
of the Bovey Tracy specimens, the Missoula cones are somewhat smaller and are
distinctly oblong.

In the Missoula mateiial there is a small leafy shoot (Plate XXII. fig. 5)
about 12 mm. long, but ■with a rather thick central axis and clothed with leaves,
which range from scale-hLe organs less than 2 mm. long at the base to ascending
lanceolate bracts at the apex about 4-5 mm. long. The upper bracts apparently
form a cup or campanulate structure resembling the arrangement of the perigonial
bracts at the apex of a rigorous Polytrichum shoot. Indeed, the fossil suggests
at once a vigorous moss shoot. It appears, however, to be of the same nature as
the fossil described rather doubtfully by Lesquereux {I.e.) under the name
of Hypnum Haydenii. Lesquereux's specimen has occasioned considerable dis-
cussion, Mrs. E. G. Britton and Dr. Arthur HoUick having referred it" to some
conifer resembhng Juniperus communis L., to young growing branchlets of which
the fossil shows considerable resemblance; while Cockerell ill.cc, above) refers the
specimen to Sequoia affinis Lesquereux; and Knowlton, still later,'* pubhshes it
as Juniperus? Haydenii (Lesquereux) Knowlton.

The Missoula specimen is found to resemble very closely the short branchlets
which constitute the pedicels of the cones of Sequoia sempervirens Endlicher.
As compared with such branchlets on specimens of the Redwood in the Carnegie
Museum {Jennings, Mill Creek Valley above Muir's Woods, Cal., 1915) the fossil
is found to have about the same size, the bases are similarly blunt and clothed with
short, thick, scale-like leaves, the apex having longer, more slenderly tipped bracts
arranged in campanulate fashion. In view of these similarities I am following
Cockerell in referring the moss-like twig to Lesquereux's Sequoia affinis, which,
however, is required to be known as Sequoia Haydenii on account, unfortunately,
of the prior publication of the supposed moss.

The third type of specimen, which I am including under the name Sequoia
Haydenii, consists of rather densely complanately leaved twigs up to 12 cm. long
(Plate XXIII, fig. 6) and with leaves spreading collectively to a width of 7-30 mm.
The leaves become abruptly much shorter for a distance of 5 cm. or more at the base

36 Saporta. Annales des Sciences Naturelles, 5 Series, IV, 1865, PI. 2, figs. 2a and 2d.

" Britton, E. G. & Hollick, A. Bull. Torrey Botanical Club, XXXIV, 1907, pp. 139-140.

38 Knowlton, F. Proc. U. S. National Museum, LI, 1916, pp. 249-250. *

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 403

of the twigs. The median leaves are linear-lanceolate to narrowly linear-oblong ;
varying on different twigs from 5-17 mm. in length and from 1-2 mm. in width;
somewhat falcate, spreading at an angle of 50-70°. The apex of the leaf is usually
rather acute, sometimes more acuminate, while the base tapers to an oblique, some-
what thickened, and rather widely decurrent insertion. This latter character forms
perhaps the most easily observable distinction between this and the somewhat
smaller-leaved Taxodium duhium (Sternberg) Heer, to which there is a fairly close
resemblance in general aspect. Heer^^ figures another character which apparently
distinguished Sequoia from Taxodium. In Sequoia there are strong cell-walls run-
ning from the midvein to the margin of the leaf and their course is often marked by
faint cross-lines on the outer surface of the leaf. In some of the Missoula fossils these
markings show quite distinctly. There is also a close resemblance to plates and de-
scriptions of Sequoia Langsdorfii (Brongniart) Heer which is a rather characteristic
Miocene species of Europe and has been reported from a number of localities in the
western part of the United States. It would seem not at all improbable that some
of the Western specimens reported as Sequoia Langsdorfii may belong to the same
species as do ours from Missoula.

Specimens of the complanately leaved type occur in the material from both of
Douglass' localities 196 and 165.

5. Thuyopsis gracilis Heer. (Plate XXIII, Fig. 5.)

Thuyopsis gracilis Heer, Flora FossiHs Arctica, VII, p. 59, PL XX, fig. 16; Schenck,
Palseophytologie, Zittel's Handbuch der Palaeontologie, II, 1890, pp. 322-323,
fig. 223.

The specimens which I have referred to this species consist of three smaU leafy
twigs, the longest of which is less than a centimeter in length. This longest twig,
shown in figure 5, matches so closely the figure of Heer's species as to leave Httle
doubt as to the identity of the two plants. In our plants the leaves are appressed,
thick, smooth, evidently shining, those on the upper face of the twig being 3-4 mm.
long, 2-2.5 mm. wide, the lower two-thirds of only the margins being covered by
the overlapping edges of the adjacent pair of lateral leaves, the back of the leaf
having a median ridge about one millimeter wide and bordered on each side by
a slight furrow, which extends uniformly the whole visible length of the leaf.
The apex of the leaf is rather blunt, thick, and incurved. The lateral leaves are
apparently inserted a little lower on the twig, being about the same length as the
others, but somewhat aarrower, the apex thickened and incurved. This approxi-

'' Flora Fossilis Arctica, I, 1868, PI. 2.

404 MEMOIRS OF THE CARNEGIE MUSEUM.

mation of the leaves into groups, almost whorls, gives the twig a peculiar jointed
appearance.

Cockerell has identified a fossil from the Florissant" as Heyderia coloradensis
Cockerell, comparing it to the modern Libocedrus decurrens Torrey (Heyderia
decurrens Koch). This plant is evidently very similar to the plant from Missoula,
which I have called Thuyopsis gracilis Heer, but the specimens from Missoula show
strongly flattened shoots with short and wide leaves, the lateral leaves spreading
rather widely, and, so far as leafy twigs of such conifers can be taken to indicate
relationships, I think the evidence shows that they are Thuyopsis rather than
Libocedrus.

Thuyopsis gracilis was described by Heer from Greenland, from beds which he
regarded as Miocene, but which are now regarded as being older, perhaps Eocene
or even Cretaceous. The modern representatives of the genus consist of one species
native to Japan (Thuyopsis dolobrata Siebold & Zuccarini) and the variety nana
Siebold & Zuccarini (T. Icetevirens Lindley) native to China. So far as I know,
Thuyopsis gracilis has not before been reported on the North American continent.
The Montana specimens came from only one locality, Douglass' "Locality 196" at
Missoula.

6. Sabina linguaefolia (Lesquereux) Cockerell. (Plate XXIII, Fig. 2.)

Glyptostrobus europceus Heer. Lesquereux, Tertiary Flora. Rept. U. S. Geol.

Surv. Terr., VII, 1878, p. 74, PL 7, figs. 1 and 2.
Widdringtonia lingucejolia Lesquereux, Cretaceous and Tertiary Floras, Rept.

U. S. Geol. Surv. Terr., VIII, 1883, p. 139, PL 21, figs. 14 and 14a.
Sabina linguaefolia (Lesquereux) Cockerell, Univ. Col. Studies, III, 1906,

p. 175; Knowlton, Proc. U. S. Nat. Mus., LI, 1916, p. 249, PL 14.

These specimens consist of several fragments of leafy twigs, mostly less than a
centimeter long, some of them irregularly and closely pinnately branched. The
leaves are 4-ranked, thick, with a rather prominent dorsal ridge, which is especially
sharp at the apex. The branches are evidently complanately flattened, but the
smaller twigs appear almost as thick as wide. The facial leaves on the larger
twigs are about 1-1.5 mm. long, the lower half overlapped on the margins by the
lateral leaves, the exposed portion of the leaf rhomboid, almost as wide as long, the
apex acute and closely appressed, thick, with a sharp dorsal ridge. On these
larger twigs the lateral leaves are about the same size or perhaps a little longer,
their lower margins meeting over and below the lower part of the facial leaf for a

*> Cockerell. Bull. Amer. Mus. Nat. Hist., XXIV, 1908, p. 78.

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 405

distance often half that of the length of the exposed part of the facial leaf. These
lateral leaves are thick, ovate, somewhat bluntly acute, the tips spreading at an angle
of about forty-five degrees. On the larger twigs the successive pairs of lateral leaves
do not reach the next higher ones, this giving the twigs a jointed appearance, but
on the smallest twigs both the facial and lateral leaves are imbricate throughout.
On these smaller twigs the leaves are mostly less than 1 mm. long, scale-hke, thick,
rather sharply dorsally carinate, there being some indication of a gland at about
the middle, the apex acutish, or on the lateral leaves often rather obtuse.

The specimens only occur in material from Douglass' " Locality 196, " Missoula,
and they are all in mixture with detached Sequoia leaves and unidentifiable frag-
ments of wood, bark, etc., a general mixture of small floating fragments, such as
can often be seen stranded along more or less protected shores and banks during
quiet weather, or more rarely water-logged and forming a layer on the bottom of a
quiet pool.

The similarity of the foliage on these twigs to that of Chamcecyparis Ehrens-
wardi Heer is such that confusion might readily occur in attempting to state the
geological range of the two genera. Sabina lingucefolia is now known to occur in
the Florissant beds of Colorado, middle Miocene, and I would have little hesitation
in referring to the same species, or at least a very closely related one, the fragment
described and figured by Knowlton from Van Horn's ranch, John Day basin, Oregon,
middle Miocene.^^ The fossils from the White River beds differ scarcely at all from
impressions such as would be formed by the modern Rocky Mountain Juniper,
Sabina scopulorum (Sargent) Rydberg, occurring on foothills and bluffs throughout
the Rocky Mountains.

7. Typha Lesquereuxi Cockerell. (Plate XXIX, Fig. 4).

Typha latissima Lesquereux, The Cretaceous and Tertiary Floras U. S. Geol.

Surv. Territories, VIII, 1883, p. 141, PL 23, figs. 4, 4a. Not T. latissima

Al. Braun.
Typha Lesquereuxi Cockerell, Fossil Plants from Florissant, Colorado, Bulletin

of the Torrey Botanical Club, XXXIII, 1906, p. 307; idem, The Fossil Flora of

Florissant, Colorado, Bulletin of the American Museum of Natural History,

XXIV, 1908, pp. 77-110, Pis. 6-10.

The specimen consists of an impression of a leaf fragment about 1.5 cm. long
by 1.1 cm. wide, marked with fine longitudinal parallel veins about 1 mm. apart.

« Knowlton. Fossil Flora of the John Day Basin, Oregon. U. S. Geol. Surv., Bull. CCIV, 1902,
p. 26, PI. 1, fig. 3.

406 MEMOIRS OF THE CARNEGIE MUSEUM.

Between these fine veins are traces of much finer veinlets, while the surface is
marked somewhat more strongly by fine transverse lines running from one vein to
the next. The leaf appears to have been fairly thick and smooth. Impressions
on the same piece of rock are probably those of stems but are indistinct and in-
definite.

According to the reports Typha appears first in the eastern United States in
the middle Cretaceous (Raritan and Magothy), next in the Eocene in Canada
(Paskapoo) and in Europe, then in the Oligocene of Europe and the Miocene of
Florida and Europe. The genus now contains about nine species well distributed
in fresh-water swamps in temperate and tropical regions.

Our specimen appears to be the same species as that figured by Lesquereux (I.e.)
and by Cockerell from the Florissant (Lc), and, judging from the wide distribution
of some of the modern species, it is not unhkely that this species had a wide dis-
tribution in the Oligocene and mid-Tertiary swamps of western temperate America.

8. Cyperacites. (Plate XXIX, Fig. 3.)
There has been referred to Cyperacites a piece of a leaf measuring about 4 cm.
long by 4 mm. wide. The midrib is narrow and prominent, and there are indica-
tions of a less prominent vein on each side of it, as well as faint indications of other
longitudinal markings. The impression is practically uniform in width throughout
its length, and the indications are that the leaf was a leathery one with a glossy
surface, such as might be the case with coniferous leaves, as, for example, Podo-
carpuH or Taxites Olriki, or with some of the species of the Cyperacece of the present
period, when growing in more or less xerophytic habitats. However, in the absence
of stems, flowers, or fruits, the identification of such a fragmentary specimen must
remain very uncertain. The specimen might with almost equal propriety be
regarded as representing a species of Podocarpus.
The specimen is from "Locality 196," Missoula.

9. Populus Zaddachi Heer. (Plate XXV, Figs. 1, 2; Plate XXVI, Figs. 1, la, 2,
3, 5, 6, and Plate XXIV, Fig. 6.)

Populus Zaddachi Heer, Flora Fossilis Arctica, I, 1868, pp. 98-99, Pis. VI, figs.
1-4, and XV, fig. 16; Lesquereux, The Tertiary Flora, U. S. Geological Survey
of the Territories, VII, 1878, p. 176, PL XXII, fig. 13; idem, The Cretaceous
and Tertiary Floras, U. S. Geological Survey of the Territories, VIII, 1883,
p. 158, PI. 31, fig. 8.
The leaves are large, the blades being 5.5-16 cm. long, by 3-12 cm. wide,

ovate to broadly ovate, or the smallest ones more narrowly ovate, the base broadly

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 407

rounded to a rather narrow and shallow cordate sinus, the insertion of the petiole
having two well-marked glands at each side, or even with a glandular or thickened
rim on the outer side, as in some modern species of Populus, the upper part of the
leaf being somewhat acuminate with a rather obtuse apex. The leaves are seven-
to five-ribbed, the lowest pair of ribs weak and short, swinging back into the
broadly rounded basal curves, these, as well as all ribs, looping in camptodrome
fashion; the next upper pair in the seven-ribbed leaves leaving the insertion at
about right angles and extending well out to the margin of the blade in a broad
upturned curve; the pair next to the midrib are stronger, ascending at an angle of
about 45-35 degrees, approaching the margin at about two-thirds the distance
from base to apex of the leaf, and during the upper half or two-thirds of their
course throwing off from their lower side widely diverging and rather strong branches,
which, swinging around and forking, loop together in camptodrome fashion within
2-5 mm. of the leaf-margin. The veinlets from these latter loops usually also
form a series of much smaller loops from which faint veinlets run out to the small
crenate teeth. The uppermost pair of ribs is only about half as wide as is the
midrib, having thus about the same thickness as the lateral veins from the midrib
itself. The midrib is strong, about 1 mm. wide, sending out four to seven pairs
of widely spreading, upwardly curving veins, either approximately opposite or
alternate, the strongest of these veins usually arising at about the middle of the
leaf or slightly below. Other fainter veins are thrown off at wide angles, some of
the finest of them at practically right angles, especially from the lower half of the
midrib. As compared with most broad leaves, the ultimate meshwork is rather
coarse. The texture of the leaves appears to have been rather thick and leathery
and the surface smooth, the larger nerves being deeply impressed on the upper
surface of the leaf and rounded but fairly prominent below.

In general shape the larger of these leaves resemble very closely those described
by Newberry as Catalpa crassifolia'^'^ or later as Aristolochia cordifolia^^. The
character of the teeth and the glandular insertion of the petiole can leave little
doubt, however, as to the propriety of placing these specimens in the genus Populus.
Berry** in connection with the description of Grewiopsis tennesseensis from speci-
mens from the Wilcox beds of Texas and Tennessee, calls attention to their resem-
blance to "the numerous forms from Greenland, Europe, and western North

''- Newberry. Annual Report, New York Lyceum of Natural History, IX, 1868, p. 56.

" Newberry. Illustrations of Cretaceous and Tertiary Plants, U. S. Geological Survey, IX, 1878, PI.
25, fig. 7; U. S. Geological Survey, Monograph, XXXV, 1898, p. 90, PL 39; PI. 40, fig. 7; and PL 60, fig. 4.

^* Berry. The Lower Eocene Floras of Southeastern North America, U. S. Geological Survey,
Professional Paper XCI, 1916, p. 286.

408 MEMOIRS OF THE CARNEGIE MUSEUM.

America that are commonly referred to the genus Populus, as Populus arctica
Heer, Populus Zaddachi Heer, Populus cuneata Newberry (a variable and common
form of the Fort Union Eocene), Populus genetrix Newberry, Populus paleomelas
Saporta, or Populus glandulifera Heer." He appears to doubt that these various
species belong to Populus and notes that "it is singular that the Arctic and early
American forms are palmately and not pinnately veined, like the modern species,
and present in a varying degree other distinctive features." In connection with
this opinion attention should be called to the distinctly palmate ribbing of our
common modern Populus deltoides, certainly just as distinctly five-ribbed as are
the five-ribbed leaves of the fossils at hand. In addition to the agreement in
venation, the presence of glands on the crenulations and at the insertion of the
petiole are further arguments for referring at least the Missoula fossils to Populus.
Sinnott and Baile\'^^ conclude among other things that "The primitive angiosperm
leaf was palmate in type, probably lobed, and was provided with three main bundles
which arose separately at the node;" and "This conclusion is based on evidence
from paleobotany, that the palmate leaf was more frequent in the Cretaceous and
Tertiary than at present."

The petiole, when preserved, is slender, but apparently rather stiff and woody,
and distinctly enlarged at its base. The length of the petiole was 5.7 cm. in a leaf
with a blade about? 12 cm. long. Another specimen, in which the blade of the leaf
was about 13 cm. long, had a petiole 6.2 cm. long.

The genus Populus is comparatively a very old one, its oldest known species
probably being Populus primceva Heer, from the Kome beds of western Greenland,
which are presumably of Potomac age" (upper part of the Lower Cretaceous).
From this time on the number of species reported increases up towards the Eocene,
from which period there are perhaps forty species already reported from the United
States alone, many of these species resembling very closely some of the living species.
The range of Populus, beginning in the far north in the Cretaceous, extended during
the latter part of the Cretaceous and in the Tertiary quite generally over the tem-
perate regions of the northern hemisphere. In western North America there have
been described from the Fort Union beds alone about as many species (25) as there
are now of living species of poplars in the whole world.

The range of Populus Zaddachi Heer is wide, the species having been reported

^* Sinnott and Bailey. Investigations on the Phylogeny of the Angiosperms, 5, American Journal
of Botany, II, 1915, pp. 1-23.

" White and Schuchert. Cretaceous Series of the West Coast of Greenland, Bulletin of the Geologi-
cal Society of America, IX, 1898, pp. 365-367.

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 409

from eastern Germany and western Greenland*^ and, in North America proper,
from Alaska, California, Colorado, Wyoming, Montana, and Dakota, from beds
variously ranging from the lowest part of the Eocene up to the Miocene.

The smallest of the leaves among the specimens are very likely those at the
apex of rapidly growing shoots, and they are much more narrowly ovate to even
lance-ovate than are the larger leaves, exactly as may be observed in Populus
balsamifera and other living species. Among the Missoula specimens is an im-
pression of a leaf-blade about 4 cm. long and 2 cm. wide (Plate XXVI, fig. 6)
which matches so closely one of the figures of Newberry's Populus cuneata^^ that
Newberry's figure might easily serve to illustrate, it It is not unlikely that imma-
ture leaves of a number of species of poplars, especially if preserved as fossils,
would be impossible or at least extremely difficult to refer to the proper species.
It is not at all improbable that some of the numerous fossil species of poplars repre-
sent such immature leaves, especially where the species have been described from
scanty material.

10. Populus smilacifolia Newberry. (Plate XXVI, Fig. 4.)

Populus smilacifolia Newberry, Annals of the New York Lyceum of Natural
History, IX, 1868, p. 66; idem, Illustrations of Cretaceous and Tertiary
Plants, U. S. Geological Survey of the Territories, 1878, PI. 14, fig. 5; idem,
Later Extinct Floras of North America, U. S. Geological Survey, Monograph
35, 1898, pp. 53-54, PL 29, fig. 5.

The specimen is from "Locality 165," Missoula, and, although somewhat in-
complete at the apex, it agrees very closely with Newberry's Populus smilacifolia,
from the Fort Union group of North Dakota.

The single specimen shows a rounded-ovate leaf from the cordate base of which
arise the midrib and two pairs of lateral veins, from the bases of the veins of the
lower pair of these arising, however, a much fainter and very short pair, so that the
leaf might be regarded as having three pairs of lateral veins. The lowermost
strong pair of veins spreads widely from the base of the leaf, curving upwards to
the margin at about half-way to the apex and sending off from the proximal side a
few widely spreading veinlets which curve upwards towards the margin. The
uppermost pair of veins, those next to the midrib, arise at a narrow angle with the
midrib and, curving slightly forwards, reach the margin but slightly below the apex.
In their upper two-thirds these veins give off short lateral branches, which curve out

" Heer, 0. Flora Fossilis Arctica, I, 1868, p. 98.

^* Newberry. The Later Extinct Floras of North America, U. S. Geological Survey, Monograph
XXXV, 1898, PI. 29, fig. 7.

410 MEMOIRS OF THE CARNEGIE MUSEUM.

and up towards the leaf-margin. So far as can be determined, the leaf-margin
appears to be but very slightly serrulate.

Populus smilacifolia as described and figured by Newberry does not have the
lowermost (third) pair of short and fine veins, as in the Missoula specimens, and
it may be possible that the latter represent only a form of the common Populus
ZaddacM Heer, the apex being but poorly preserved. The resemblance to Populus
smilacifolia is so close, however, that the specimen has been provisionally referred
to that species.

11. Juglans pentagona Jennings, sp. nov. (Plate XXIX, Figs. 1, la, 2, 2a.)
This species is based on the impression of a nearly complete leaflet about 6 cm.
long by 4 cm. wide, broadly ovate, rather abruptly rounded to a bluntly acute
apex, the base being apparently broadly rounded. The midvein is fairly strong;
secondary veins, about thirteen pairs, varying from alternate to opposite, the
lowermost arising from the midvein at a rather acute angle and then curving quickly
outward to a course at almost right angles to the midvein, then curving upward
toward the margin, the median and upper veins spreading from the midrib at an angle
of 25-30° and curving gradually upward towards the margin. All the veins unite
in wide camptodrome loops with the lower tertiaries from the next upper vein,
these loops usually running to within a millimeter or two of the leaf-margin and
giving off ia turn finer loops reaching practically to the margin. The tertiaries from
the median and upper secondaries, especially, leave the secondaries at right angles
at distances of 2-4 mm. apart, forking and meeting in an alternate manner about
midway between the secondary veins, so as to form approximately pentagonal areas.
Within these meshes the finer veinlets form rather distinct polygonal meshes mainly
about 0.3-0.7 mm. wide. The margin of the leaf is entire, but shghtly undulate.
The lowermost secondaries are considerably closer together than are the median
and upper ones.

In another fragment of rock from this same locality is a leaflet which I take to
represent the same species as that described above. It is 8 cm. long by 2.2 cm.
wide, lanceolate, the base unequal, being rounded on the one side and tapering in
almost a straight line on the other side, the apex being rather slenderly acuminate.
The leaf-margin is entire. The midvein is strong, the secoadaries being in about
seventeen pairs, the lowermost leaving at an acute angle, then curving more widely,
then again curving forwards towards the margin where they become camptodrome
with tertiaries from the next upper secondary. The median and upper secondaries
spread quite widely and towards the margin send off proximally strong tertiaries, or

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 411

they sometimes fork. Between these median and upper secondaries there are a
few intermediate shorter secondaries, which sometimes curve around and loop with
the main adjacent secondary at perhaps one-half to two-thirds of the distance from
the midvein to the margin.

The wider impression, the first of the fossils just described, is taken as the type
of the species, the specific name having been suggested by the more or less distinctly
pentagonal areas formed by the tertiary veins. The specimens are from Douglass'
"Locality 165," Missoula, and are associated in the same blocks with Populus Zad-
dachi Heer, Betula multinervis Jennings, Sequoia Haydenii (Lesquereux) Cockerell,
and Alnus Hollandiana Jennings.

The genus Juglans has about twelve living species ranging from southeastern
Europe to eastern Asia, and in North America from the temperate regions south to
Mexico. The genus also occurs in the Andes of South America. About forty
fossil species have been referred to the genus, beginning rather early in the creta-
ceous (Dakota, Magothy, Raritan beds), the number of species increasing to be-
tween twenty and thirty in the Eocene, a few in the Oligocene, about forty reported
for the Miocene, and about thirty in the Pliocene. The genus was widely distrib-
uted over the northern hemisphere, especially during the Eocene, ranging from the
southeastern part of the United States to the middle and northwestern United
States, British Columbia, and Alaska. The distribution during the Miocene was
apparently more southern (Florida, California, Brandon beds of Vermont, John
Day beds of Oregon), no occurrences having been noted farther north in America
than Oregon and Vermont.

Juglans pentagona is perhaps most nearly related among fossil plants to Juglans
crassifolia Knowlton, common in the uppermost John Day beds^^ and regarded as
probably Oligocene, and to /. rugosa Lesquereux, reported from the Laramie and
Montana formations (Cretaceous) and, more recently by Knowlton^" from the
Eocene (Raton Formation) of Colorado and New Mexico.

12. Betula multinervis Jennings, sp. nov. (Plate XXIV, Fig. 4; Plate
XXVII, Figs. 1, la, 16, Ic, 2; Plate XXVIII, Fig. 2.)

The leaf-blades vary from 4-9 cm. long to 2.5-5 cm. wide, being lance-ovate
to ovate-oblong or widely ovate, the petiole slender, about 1 cm. long, the leaf-base

" Knowlton. Fossil Flora of the John Day Basin, Oregon, U. S. Geological Survey, Bulletin
CCIV, 1902, p. 36, PI. 4, fig. 3.

^ Knowlton. Fossil Floras of the Vermejo and Raton Formations of Colorado and New Mexico,
U. S. Geological Survey, Professional Paper CI, 1917, p. 293, PI. 112, fig. 4.

412 MEMOIRS OF THE CARNEGIE MUSEUM.

rounded or faintly subcordate, occasionally somewhat inequilateral, the apex
slenderly acute to long acuminate, and the margin of the leaf sharply doubly serrate
almost to the base. The tooth at the apex of each secondary vein appears larger
than the intermediate teeth, because the leaf-margin slopes inward and back-
ward from this tooth to a rather deep acute sinus in front of the next main tooth,
the intermediate teeth being not much smaller than the main tooth, but situated
successively lower down on the slope from it to the main sinus. The midrib and
veins are deeply impressed on the dorsal surface of the leaf, the veins being usually
in 15-16 pairs (13-18), close, almost straight, parallel; in the wider leaves giving off
toward the margin from one to four strong branches, which swing down and run
out into the intermediate teeth. The tertiary veins are rather prominent, mainly
running straight across from one secondary vein to the other and forming nearly
right angles with them, sometimes forking or irregularly anastomosing about halfway
between them. On the upper surface of the leaf the deeply impressed character of
the venation resembles the somewhat rugose surface, which occurs in some of the
living species of Ulmus.

The fruits associated with the leaves and probablj^ belonging to the same
species, although not attached to the same twig with any of the leaves, occur only
in "Locality 165," at Missoula. They are evidently narrowly oblong-cylindrical,
about 5 mm. thick by 1.5 cm. long, the scales being about 4 mm. long, their three
obtuse lobes reaching to about an equal height, the outer lobes about 0.8 mm. wide,
ascending at an angle of about 40° from a rounded sinus, the median lobe being
narrower. The main outline of the scale is basally rounded and then narrows rapidly
to an acuminate tapering portion about 1 mm. long.

The puzzling similarity between the leaves of species of Carpinus, Ostrya, and
Betula cannot but cause some uncertainty as to the generic position of the material.
It is quite generallj'^ stated that the teeth of Ostrya are simple and somewhat
smaller than are the more or less serrate teeth of Carpinus. The specimens show
rather fine teeth, which, as far as could be determined from the specimens from Mis-
soula can not be said to be serrate. Further, in the modern species of these genera
Carpinus has little or no indication of branches running out from the lower side of
the veins to form the secondary serrations, but this is quite characteristically the
case in our modern Ostrya virginiana. The specimens from Missoula agree in this
respect with Ostrya, rather than with Carpinus. However, this method of branch-
ing is also quite characteristic of some of the species of Betula, such as Betula lenta
of eastern North America, and a careful comparison of the specimens before me
with leaves of Ostrya and Betula reveals no diagnostic character by which the

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 413

fossil plant might be referred to one of these genera and not to the other. The
disposition of the species under Betula practically rests only upon the fact that there
were associated with the leaves some specimens of cones, which can be none other
than those of Betula, and as there are no leaves of other species among the fossils
which can be referred to Betula, it is assumed that the cones belong to the species,
the leaves of which are so abundant in the rocks at that place.

Impressions of these leaves occur abundantly in the collections from both of
the localities at Missoula, the most complete specimens being from " Locality 196."
The fruits are represented only from "Locality 165."

The genus Betula is reported first in North America from the Dakota group
in the Cretaceous, thence extending through the Montana and the Laramie into
the Eocene, where it is represented by more than a dozen species. In the North
American Miocene there are reported about a half-dozen species.

13. Alnus HoUandiana Jennings, sp. nov. (Plate XXV, Fig. 3; Plate XXIV,

Fig. 8; Plate XXVIII, Fig. 1; Plate XXX, Figs. 1, la,

Type; fig. 3, Cones.)

The leaves are variable in size, the blades of the largest being about 12 cm.
long by 5.5 cm. wide, elliptic to oval-elliptic, the apex being rather widely acute,
the base acuminately narrowed into a slender petiole, which in one specimen reaches
a length of 3.5 cm. The leaf-margins have small, low, somewhat crenate teeth,
which are tipped with a glandular or at least a thickened point, the teeth disappear-
ing along the basal 1-2 cm. of the margin. The midrib is rather strong, sending off
from nine to twelve somewhat upwardly curved parallel veins, the uppermost of
these more or less directly running out into the teeth, the greater number of them,
however, curving a little and with branches looping in camptodrome fashion
quite close to the margin and sending off minute branches which themselves ter-
minate in the teeth. Usually the base of the secondary vein bends down slightly
where it joins the midrib, thus forming a more acute angle. The tooth into which
the vein runs, especially in the upper part of the blade, or which most closely ap-
proaches the vein in the lower part of the blade, is somewhat larger than the inter-
mediate teeth, it having a height of 1-1.5 mm. There are three to five of these
intermediate teeth between each pair of the main teeth. The veinlets (tertiaries),
rimning across from one vein to the next, do so at about right angles to the veins and
are rather far apart (about 2-4 mm.), the enclosed areas thus being approximately
rectangular, and about two to three times as long as wide. The ultimate meshwork
is relatively quite fine, most of the veinlets visibly having their ends free. The leaves

414 MEMOIES OF THE CARNEGIE MUSEUM.

appear to have been rather thin but yeb stiff, leathery, and especially on the lower
side quite smooth and, perhaps, shining. The venation is impressed on the upper
surface of the leaf, even the finest meshwork showing on some of the impressions.
On the lower side of the leaf the venation is decidedly prominent, even to the finest
meshwork.

In some of the specimens the veins in the upper part of the leaf run almost
directly to the tooth, although sending off camptodromous branches towards the
margin, the tip of the vein which runs out into the tooth often being reduced to a
slender nervule not much stronger than those which run out into the intermediate
teeth. In general shape and also in venation there is considerable resemblance to
the terminal leaflet of some of the species of Hicoria and Juglans, but the resem-
blance to Alnus, such as Alnus rhombifolia Nuttall, of California, or even of some
of the more acute leaves of forms of Alnus rugosa (DuRoi) Sprengel is closer.
In size and in the acute outline of the base and apex the leaves are likewise very
similar to those of the Mexican Alnus glabrata Fernald {See Pringle's No. 8022,
from Tizapan, Mexico, 1899.)

The Missoula species is closely related to Alnus carpinoides Lesquereux from
Bridge Creek, Oregon, (Upper Eocene), but differs in that the leaves are more oblong
and less ovate than in the Oregon species. Practically the same characters distin-
guish the Missoula species from Alnus serrulata fossilis Newberry, also occurring
in the deposits of Bridge Creek, Oregon. The lower part of the leaf in the Missoula
specimens begins to narrow from about the middle of the blade and finally tapers
quite accuminately to the petiole.

There is a fine series of leaf impressions of this species from Mr. Douglass'
" Locality No. 196 " and a few from " Locality 165," many of them fragmentary, but
representing various sizes and considerable variation, principally with regard to the
apex, this occasionally becoming blunter, especially among the smaller leaves.
Among these smaller leaves it sometimes becomes difficult to make a satisfactory dis-
tinction between this species and the most acute forms among the larger leaves of
Alnus microdontoides with which latter species Alnus Hollandiana is frequently asso-
ciated in the same pieces of rock. Nevertheless, the majority of the specimens of
the two species show clearly as much difference as would be found in a similar asso-
ciation of specimens of leaves from different species of living alders.

This fine species is named in honor of Dr. William J. Holland, Director of the
Carnegie Museum, at whose request the study of the fossil plants from the Oli-
gocene beds of volcanic dust at Missoula was undertaken and which has led to the
preparation of this paper.

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 415

14. Alnus microdontoides Jennings, sp. nov. (Plate XXIV, Fig. 7; Plate
XXX, Figs. 2 and 2a, Type.)

The leaves are 3.5-8 cm. long, and 2-3 cm. wide, widest somewhat above the
middle, the blade being narrowly obovate to broadly oblong-elliptic or even some-
what ovate, narrowed acutely to acuminately at the base, petioles slender, up to
13 mm. long, the apex widely rounded, the tip itself usually somewhat retuse
varying to obtuse or rarely acutish. The midrib is strong and deeply impressed
dorsaUy, ventrally standing out sharply and prominently. The secondaries are
also impressed dorsally and prominent ventrally, springing from the midrib at an
angle of about 45°, there being eight to eleven pairs, either alternate or opposite,
evenly spaced, parallel and straight to near the margin, then curving slightly for-
ward and usually ending in a tooth, but before doing so, branching and becoming
very slender, the branches being few, springing from the lower side of the vein and
curving out to the margin and there ending in teeth or variously anastomosing.
The tertiaries are spaced about 1-3 mm. apart, rather strong, distinctly impressed
above and prominent ventraUy, springing from the secondaries at a wide angle and
curving slightly outward and running across to the next secondary, or forking and
joining with the forks of the adjacent secondary, the final mesh work being fine and
indistinct. The margin of the leaf is minutely serrate, there being from two to
four slightly smaller teeth between each pair of those teeth which terminate the
secondary veins. The teeth are sharply glandular- or callus-tipped and are
rather prominently directed forward.

In general appearance the leaves resemble rather closely the form of Alnus
rugosa known as variety serrulata (Alton) Winkel (Alnus serrulata Willdenow).
They seem to bear much the same relation to this modern American plant that the
similar and approximately contemporaneous Alnus microdonta Saporta, from the
Armissan of southeastern France, bears to the modern Mediterranean Alnus
glutinosa var. denticulata (Meyer) Ledebour (Alnus oblonga Willdenow). In the
leaves of Alnus microdontoides the serrulations extend along the margins of the
leaves to within a centimeter or less above the the base, considerably farther than
Saporta figures for Alnus microdonta. ^^

As has been pointed out in Gray's Manual of Botany^^ there is considerable
intergradation, in the northern part of the range of Alnus rugosa, between forms
of that species and the equally variable Alnus incana, of somewhat more northern

^' Saporta, G. Etudes sur la V^g^tation du Sud-est de la France a I'Epoque Tertiaire, Annales des
Sciences Naturelles, Botanique, Ser. 5, IV, 1865, p. 110, PL 6, fig. 3.

^^2 Gray, Asa. New Manual of Botany, Seventh Edition, 1908, p. 337.

416 MEMOIRS OF THE CARNEGIE MUSEUM.

range. Specimens referable to Alnus rugosa show a greater variability than is
shown in the numerous leaf-impressions from the Missoula beds which I have
referred to Alnus microdontoides. During the first part of my studies on these
specimens the attempt was made to differentiate two species, one with a fairly
evenly serrate oblong-elliptic leaf, with a blunt or retuse apex and an acuminately
narrowed base, the other with a more plainly doubly serrate leaf, relatively wider,
more acute at the apex and less acuminately narrowed at the base. Further
studies of material later found in another box with a large number of intermediate
specimens disclosed the fact that no separation of these extremes could be made
other than in a purely arbitrary manner.

Beginning in the upper Cretaceous, the genus Alnus attained in the Miocene
a general distribution through the arctic and northern North American and Eurasian
regions. Altogether there have been described about forty fossil species, mostly
from the Miocene, although in the western part of the United States a number of
species have been reported from the Eocene, particularly from the Fort Union beds.
There are now recognized about thirty living species, these ranging well over the
northern hemisphere, and in America extending south to Peru.

15. Quercus laurosimulans Jennings, nom. nov. (Plate XXVIII, Fig. 3;
Plate XXXI, Figs. 3 and 3a.)

Quercus laurifolia Newberry, Proceedings of the United States National Museum,
V, 1883, p. 505; idem, The Later Extinct Floras of North America, U. S. Geo-
logical Survey, Monograph XXXV, 1898, p. 76, PI. 59, Figs, 4 and 60, and
PL 60, fig. 3. Not Quercus laurifolia Michaux, Histoire des Chenes de
I'Amerique, 1801, No. 10, PL 17.
Newberry's original description is as follows :

"Leaves petioled, lanceolate, 6 inches in length by IJ^ inches in width, equally
narrowed to the point and petiole; margins entire or faintly toothed or undulate;
nervation regular; midrib strong, straight, lateral branches, about ten pairs,
arching gently upward, terminating in the margins".

The leaf -blade in the best Missoula specimen is between 10 and 11 cm. long,
by 4 cm. wide, elliptic lanceolate, rather slenderly acuminate at both base and apex,
and with a slender channeled petiole at least 2.5 cm. long, probably even longer.
The midrib is strong, rather wide (about 1 mm.), flat, sunken in the dorsal surface of
the leaf and sending off at wide angles about twelve pairs of slender but prominent
veins, which curve upwards towards the margin where the attenuate ends run almost
parallel to it and apparently form loops with the short branches from the next upper

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 417

vein. Between the main veins the midrib gives off also short but prominent inter-
mediate veins forming practically right angles with it, these short veins forking and
disappearing at a distance of 4-6 cm. from the midrib. The veinlets from the
secondary veins are irregularly placed and form wide angles with the secondary
veins and finally anastomose to form a rather coarse meshwork with irregular
angles. The lowermost veins, even those in the attenuate base, leave the midrib at
about the same wide angle as those in the middle of the leaf, running quickly out
to the apparently slightly re volute margin. The margin is entire but slightly
undulate in places. The venation is mostly rather deeply impressed on the dorsal
surface of the leaf and prominent on the under surface. The extreme apex of the
leaf is broken off in the fossils at hand.

The name Quercus laurifolia having been used at an earlier date by Michaux
for the well-known Laurel Oak of the southeastern United States, it becomes
necessary to rename Newberry's Tertiary species. The names laurina, laurifolia,
laurophylla, lauriformis and lauroides having been used for various species of fossil
or living oaks with leaves resembling those of some of the Lauracece, I have chosen
the name laurosimulans in order to preserve as nearly as possible the meaning of
the name used by Newberry for the fossil species.

The specimen first studied was referred to Laurus but further study led to a
decision in favor of Quercus. My reasons for referring the specimen to Quercus
rather than to Laurus are as follows: The rather numerous and prominent but
short veins given off from the midrib between the larger main veins and at approxi-
mately right angles to the midrib ; the rather strong branching and camptodromous
looping of the outer ends j of the veins; the veins in the attenuate base of the leaf
leaving the midrib at practically the same angle as those in the middle and upper
parts of the leaf; the impressed, but rather flat, dorsal surface of the midrib; and the
slenderer petiole.

The general outline of the leaf is very close, indeed, to that of Laurus princeps
Lesquereux, as figured from Corral Hollow, California. The resemblance to other
species of the Lauracece, such as Nectandra, is striking, as is also the resemblance to
the leaves of some of the living species of the Myrsinaceoi, such as Ardisia, Icacorea,
and Myrsine, but in these genera the midrib does not usually give off the short
intermediate veins such as appear so prominently in the Missoula specimens, or, if
present in the Myrsinacece, they are not at all prominent and, further, the petioles
are almost invariably quite short.

Newberry's Quercus laurifolia was described from specimens obtained from
"Burned shales over lignite beds. Fort Berthold, Dakota," now regarded as Fort

eWMTA

418 MEMOIRS OF THE CARNEGIE MUSEUM.

Union in age^" (Eocene), thus not more distant from the OUgocene than many other
closely related species in the Tertiary.

About two hundred fossil species of oaks have been described, beginning in the
Cretaceous, during which period the genus was widely distributed in western Europe,
the United States, and in Greenland. In the Tertiary the genus occurred in Austra-
lia and quite abundantly in the northern hemisphere, in what are now temperate
regions, as well as farther north in Greenland and Alaska. In North America oaks
were particularly abundant in the Dakota and up through the Eocene and Miocene,
and in Europe they appear to have reached their maximum in the Oligocene and
Miocene.

Oaks with entire margins ajDpear from the evidence thus far furnished by fossils
to have been relatively more numerous in the Tertiary than at the present time.
In the Oligocene and Miocene there have been reported as oaks with entire margins
at least the following: Quercus neriifolia A. Braun, Q. elcena Unger, Q. Lyelli Heer,
Q. chlorophylla Unger, Q. Daphnes Unger, Q. elceomorpha Saporta, Q. lauriformis
Saporta, Q. soda Saporta, Q. areolata Saporta, Q. elliptica Saporta, and Q. simulata
Knowlton.

16. Quercus flexuosa Newberry. (Plate XXXI, Figs. 1 and la.)

Quercus flexuosa Newberry, Boston Journal of Natural History, VII, 1863,

p. 521; idem, The Later Extinct Floras of North America, U. S. Geological

Survey, Monograph XXXV, 1898, p. 74, PL 19, figs. 4-6.

The single specimen consists of the impression of part of a leaf, the base and

apex being missing. The impression shows the leaf to have been somewhat curved

and about 9 cm. long by 3.5 cm. wide, narrowly elliptic oblong, the basal portion

evidently narrowing inequilaterally. The margin has a few unequally spaced,

sharp, small teeth, these being directed forwards. The midrib is strong, the

secondaries fairly so, alternate, spaced about 5-9 mm. apart, arising at a wide

angle and swinging forwards, being branched towards the margin of the leaf and

these branches anastomosing in camptodrome fashion. Between the secondaries

the midrib sends off fine veins which anastomose with fine veins or their branches

from the secondaries, the meshes thus formed being potygonal, with the sharper

angles and the longest dimension directed at about right angles to the midrib.

The specimen matches Newberry's figures very closely as to size, outline, and
venation, although the inequilateral outlines in both Newberry's figures and in

'' Merrill, G. P. Catalogue of the Type and Figured Specimens of Fossils, Minerals, Rocks, and
Ores. Part II. Bulletin of the United States National Museum, LIII, Part II, 1907, p. 283.

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 419

the Missoula specimen suggests that the impressions may perhaps represent leaflets
of a compound leaf rather than a leaf of Quercus.

Newberry's specimens were from near Bellingham, Washington, in rocks of
the Puget Sound group, thus possibly Oligocene, so that the species may have had a
general range over the region now separated into two floral regions by the Cascade
Mountains. The Missoula specimen was from Douglass' " Locality 165 " and was
accompanied in the same block by Betula multinervis and Sequoia Haydenii.

17. Quercus approximata Jennings, sp. nov. (Plate XXVII, Figs. 3

and 3a, Type.)

The specimen consists of an impression about 6 cm. long from an oblong leaf
of a maximum width of 2.8 cm., the basal portion of the leaf being missing. The
leaf was pinnately veined, the midrib and secondaries being quite prominent, the
secondaries arising from the midrib about 7-11 cm. apart, but forming with the
midrib angles of but 20-30 degrees. Some of the veins are a little more widely
diverging at the very base, but immediately above this the veins all pursue straight
and parallel courses to the margin, where they end in rather low but sharply crenate
or forwardly-directed and evidently often slenderly spine-tipped teeth. Along
the margin of the leaf, between each pair of the main teeth, are from one to four,
usually two or three, similar teeth of about the same size as the main teeth. These
intermediate teeth are at the ends of fine tertiaries which swing off from the lower
side of the next upper secondary vein. On the specimen at hand one of the secon-
dary veins is strongly but acutely forked at about two-thirds of the distance from
the midrib to the margin of the leaf. The leaf was evidently distinctly leathery in
texture, the impression showing a smoothish surface on which the tertiary veins
are almost indistinguishable, being obscured by the very fine but unusually distinct
ultimate meshwork.

The specimen is from "Locality 196," Missoula, associated in the same piece of
rock with fragments of two other leaves of probably the same species, and also with
Betula multinervis.

The species is nearly related to Quercus furcinervis americana Knowlton,
reported from the Miocene of the Yellowstone National Park (Lamar) and also
from the Eocene of the John Day beds of Oregon (Cherry Creek), and is perhaps
about as closely related to the following species reported by Heer from Greenland :
Q. Olafseni Heer, Q. platania Heer, Q. Steenstrupiana Heer, and Q. furcinervis
Rossmsessler. The species from Missoula differs from all of these, however, in
the much narrower angle between the secondary nerves and the midrib, and also
in that its tertiary veins are so much more obscure. The species clearly belongs to

420 MEMOIRS OF THE CARNEGIE MUSEUM.

the Chestnut-oak group, the straight, parallel, rather closely pinnate secondary-
nerves, as well as the character of the teeth and the firm reticulate surface of the
leaf, all suggesting Castanea.

. The specific name " approximata" has been used for this species because of the
short distance between the secondary veins, this feature being due to the relatively
narrow angles formed by the secondaries with the midrib.

18. Ficus (?) prunifolia Jennings, sp. nov. (Plate XXXII, Fig. 1 and la, Type.)

The specimen consists of the impression from a piece about 7 cm. long from the
middle of a leaf about 7 cm. wide, pinnately veined, the secondaries being spaced
about 3-13 cm. apart, given off from the midrib at an angle of 50-55° and curving
gradually forward, in the outer part giving off strong branches which loop in
camptodromous fashion with the curved and attenuate end of the next lower secon-
dary. From the midrib and from the lower side of the secondaries are given off
numerous fine but distinct veins, which pursue a course almost at right angles to
the midrib, and fork and anastomose to form polygonal, often diamond-shaped,
areas, the sharper angles and longest dimension of which lie cross-wise to the leaf.
Smaller and weaker camptodromous loops are formed closer to the leaf-margin by
branches from the main loops. So far as preserved the leaf-margin appears to be
entire, or at the most but slightly undulate. The venation appears to have been
rather deeply impressed and in texture the leaf was probably rather thick.

The specimen came from " Locality 196," Missoula, and is on the same piece of
rock with impressions of Betula multinervis and Alnus Hollandiana. The generic
position of the species has been the cause of much perplexity. The rather striking
crosswise trend of the finer veins and their meshes is suggestive of species of Ficus,
Diospyros, Teryninalia, various genera of the Ebenacece, Lauracece, and other
plants, but most of all, perhaps, it is suggestive of some of the larger leaved-species
of Prunus, such as P. alabamensis Mohr. This resemblance to Prunus, however,
is not so close, when the outermost course of the veins and the character of the
leaf-margin are also taken into account, so that the species seems best referred to
the genus Ficus.

In Ficus there have been reported probably between two and three hundred
fossil species, beginning well down in the Cretaceous, thirty or more being reported
from the Dakota of the western part of the United States. During the Cretaceous
the genus was widely distributed, species being reported from Greenland, Europe,
North America, Australia, and New Zealand. In the Eocene there are about as
many reported, fifty or more; sixty or more from the Oligocene, mainly in western

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 421

Europe; while about ninety species are reported for the Miocene, about twenty of
these being from the United States, and about twenty are reported from the Plio-
cqjie. The range of the genus has been extended by reports of its discovery in
Africa from the Ohgocene and in Asia from the Miocene.^*

19. Ilex furcinervis Jennings, sp. nov. (Plate XXIV, Fig. 5, and Plate
XXXII, Figs. 2, 2a, and 26, Type.)

The extreme apex and base of the leaf is lacking in our specimen. The im-
pression shows the leaf to have been obovate, probably about 8 cm. long, about 4
cm. wide, at the widest point, somewhat above the middle, narrowing rather rapidly
towards the base, apparently rounded or at least narrowing very rapidly towards
the apex. Margin entire in the lower half of the leaf, serrulate above, the teeth
being widely triangular, about 0.5 mm. high, sharply callus-tipped, this tip directed
forward and in the fossil showing a reddish-brown color. Midrib prominent,
sending off about twelve pairs of rather prominent and mostly alternate veins, which
leave at an angle of about 55-60 degrees, rather irregularly spaced, slightly curv-
ing upward, forking in their upper two-thirds or three-fourths, these forks them-
selves forking and their branches meeting to form irregularly diamond-shaped
areas extending to within 1-3 mm. of the leaf-margin. From the outer ends of
these diamond-shaped areas one or usually two nervules diverge, again forking
and looping in camptodromous fashion or disappearing into the minute teeth.
Usually it is the upper one of the two nervules leaving the apex of an area which
runs out into the tooth. In the middle of the leaf the tertiaries and the minute
ultimate meshwork are faint, suggesting that they were embedded in the tissue of
a thick leaf and are apparently rather irregular. The leaves were evidently not
only thickish but coriaceous and smooth.

In general outline the leaf was not unlike the wider leaves to be found on
vigorous shoots of our living southern Ilex Cassine Linnaeus, and it also resembles to
a certain extent Ilex longifolia Heer," both in venation and in that the margin is
toothed above. The general aspect of the leaf is that of the more obovate leaves
of Quercus imbricaria Michaux, our modern Shingle-oak, and there are resemblances
also to Quercus furcinervis americana Knowlton, reported for the Eocene and Mio-
cene.

The genus Ilex contains about 275 living species, mostly in North and South
America and temperate and tropical Asia, a few occuring also in Africa, Australia,

5< Berry, E. W. The Lower Eocene Floras of the Southeastern North America, U. S. Geological
Survey, Professional Paper XCI, 1916, pp. 82-8.3.

" Heer, 0. Flora Fossilis Arctica, I, 1868, p. 124, PI. 48, figs. 3-6.

422 MEMOIRS OF THE CARNEGIE MUSEUM.

and Europe. More than one hundred fossil species have been reported, thirteen or
more of these having been accredited to the Upper Cretaceous from North America,
Greenland, and western Europe, and about fourteen in the Eocene from the eastern
and western United States, Alaska, Greenland, and western Europe. There are
twenty or more species reported for the Oligocene and more than fifty for the
Miocene. ^^ The occurence of Ilex in the Oligocene in the region of Missoula is
thus rather to be expected than otherwise.

The specimen in the collections of the Carnegie Museum consists of the obverse
and reverse impressions of a single leaf and it was found at "Locality 196", Missoula.
The specific name furcinervis has been chosen to indicate, as in the case of Quercus
furcinervis, the characteristic strikingly forked branching of the secondary veins.

20. Celastrus parvifolius Jennings, sp. nov. (Plate XXXI, Figs. 2 and 2a, Type.)

The single specimen shows an oblong-ovate leaf 11 mm. wide and evidently
about 3 cm. long, the apex being broken away. The base of the leaf narrows evenly
and rather acutely, being apparentlj^ sessile, but this latter feature can not be
stated definitely. The leaf is pinnately veined, the midrib being fairly strong, the
secondary veins being irregularly spaced, about four of them on each side of the
midrib, from which they spring at an angle of about 45 degrees. The secondary
veins curve gradually forward to near the margin of the leaf where they merge
into a series of camptodromous loops with branches from the next upper secondary
vein. The finer veins are quite irregular in spacing and direction, thus giving rise
to an irregular, although somewhat coarse meshwork. The leaf-margin, with
the exception of that of the cuneate base of the leaf, is rather finely serrulate with
low teeth, directed somewhat forward, there being usually a fine vein extending
into each of these teeth from the marginal camptodromous loops. The shape of the
upper part of the specimen suggests a rather slenderly tapering apex.

The specimen is from "Locality 196," Missoula, and it perhaps most nearly re-
sembles Celastrus fraxinifolius Lesquereux, from Florissant, Colorado (Miocene),
and C. Lindgreni Knowlton, from the Payette of Idaho (Upper Eocene), although it
is smaller than either of these. The generic position is none too certain, the leaf
being suggestive of genera of the Rosacea, Leguminosce, Rhamnacece, and Ericacece.
Considering altogether the characters of leaf-margin, outline, and venation, par-
ticularly the method of looping and the finer meshwork, it seems best to refer the
plant to Celastrus.

*^ See Berry, E. W. The Lower Eocene Floras of Southeastern North America, U. S. Geological
Survey, Professional Paper XCI, 1916, pp. 104-105.

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 423

The genus Celastrus now contains over thirty species of shrubs, ranging
through southern and eastern Asia to AustraUa and America, mostly confined to
warm cHmates. The oldest known species {Celastrus ardica Heer) is reported
from the Cretaceous (Raritan and Magothy of New Jersey and Maryland, and the
Patoot of Greenland). About thirty species are reported from the Eocene,
ranging over England, the eastern and western United States, Alaska, and Greenland.
About the same number are reported from the Oligocene, evidently all European,
and fifty or more are reported from the Miocene of the United States (Virginia,
Colorado, Idaho, and Oregon), Europe, Asia, and Australia. Perhaps a dozen
Pliocene species are known."

It is interesting to note in this connection that no species of Celastrus has been
reported heretofore from the Oligocene of America and that the geographically
nearest locality for the occurence of Celastrus in other horizons is that of the nearly
related Celastrus Lindgreni Knowlton in the Payette formation of western Idaho,
probably of late Eocene age.

21. Acer oregoniantim Knowlton. (Plate XXXII, Fig. 3.)

Acer, fruits of, Lesquereux, Proceedings of the U. S. National Museum, XI,

1888, p. 15, PI. 6, figs. 2 and 3.
Acer oregonianum Knowlton, Fossil Flora of the John Day Basin, Oregon, U. S.

Geological Survey, Bulletin CCIV, 1902, p. 75, PI. 13, figs. 5-8.

Knowlton, I.e., says of this species: "Fruits long and broad-winged, the axis
being evidently very thick and provided with numerous strong veins; nucleus
large, round, showing broad truncation where attached to the sister-fruit. . . . They
range in length from 3.5-4.5 cm. The wing is unusually broad, being not infre-
quently 1.75 cm. wide. It is filled with numerous strong veins which are given
off from the axis of the fruit in groups or bundles. . . . Abundant in Mascall beds
at Van Horn's ranch and vicinity."

The Missoula specimen consists of a part of a fruit, comprising the upper part
of the seed and a little more than 2 cm. of the wing. The bundles of strong veins
given off from the seed are quite prominent, these opening out into the membrane
of the wing at about right angles to the axis of the wing and forking from one to
three times. The widest part of the wing is about 14 mm.

This specimen is from "LocaUty 165," Missoula. As Knowlton has pointed
out, the fruit is very close to that of the modern Acer macrophyllum Pursh, found

" See Berry, E. W. The Lower Eocene Floras of Southeastern North America, U. S. Geological
Survey, Professional Paper XCI, 1916, p. 105.

424 MEMOIRS OF THE CARNEGIE MUSEUM.

in the coastal region from Alaska to California, and now the only large native
maple-tree west of the Rocky Mountain region.

Acer now comprises about one hundred and twenty species, in the northern
hemisphere, mainly in temperate regions. Reports of the occurrence of the genus in
the Cretaceous are perhaps rather doubtful. More definite are the reports of its
occurrence in the Eocene (England), while in the Oligocene various species occurred
in widely separated regions : Spitzbergen and southward in Europe to the Mediter-
ranean, Greenland, Alaska, and in the western United States. During the
Oligocene and Miocene the species were especially numerous in western and central
Europe.

22. Alalia longipetiolata Jennings, sp. nov. (Plate XXXIII, Figs. 1, la, 2,

2a, Type.)

The material from " Locahty 139," near Winston, Montana, contains numerous
fragmentary leaf-impressions, of which a number show the leaf-base and petiole,
but none of them show the complete apex. Although quite variable, the impres-
sions apparently aU represent a species of Aralia.

The leaves were lance-ovate to oblong-ovate, reaching a length of 7 cm. or
more, the width being about hah that amount. The petioles were slender, the
longest ones preserved being about as long as the leaves were wide. The leaf was
rather distantly pinnately veined, the secondaries being mostly six to eight on
each side of the midrib, the lowest opposite or essentially so, the median and upper
usually alternate. The veins form an angle of about 45 degrees with the midrib,
then curve gently forward, one occasionally forking in the outer third. The
secondaries are usually simple, but well out towards the margin they throw off at
wide angles from one to three tertiary veins, which curve around and, like the
attenuate tip of the secondary, end in low teeth, which are either sharply directed
forward or else are broadly rounded-crenate. The leaf-base was equally or some-
times unequally broadly rounded and shallowly cordate, most of the leaves having
one or two pairs of smaller more widely spreading secondary veins crowded into
the space below the lowest main pair of secondaries. The appearance is almost that
of a sub-peltate leaf, remotely suggesting leaves such as those described at various
times under the names of Credneria, Aspidiophyllum, and Protophyllum. The
tertiary veins are weak, rather closely spaced, and diverge from the secondaries
and from the midrib at almost right angles. They mostly fork and join midway
between the secondaries to form roughly pentagonal areas which are one to two
times as high as wide. As far as can be determined from the specimens, the apex

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, "WESTERN MONTANA. 425

was acute or perhaps even slenderly acuminate. The impressions indicate that
the texture of the leaf was thin, like that of a shade-leaf.

Most of the fossil species of Aralia described have been of the type having
palmate veins and lobes, or else being palmately compound, but the Winston species
so closely resembles the modern Aralia racemosa L., that the writer has little hesi-
tation in referring it to the genus Aralia.

Broadly rounded crenate teeth, such as occur on the margin of a few of the
Winston fossils, are sparingly found in the modern Aralia racemosa, which rather
regularly has the petiole long and slender, the base unequal, the basal secondary
veins peculiarly crowded, and the leaf-blades thin, while the pattern of the vena-
tion, too, is much like that of the Winston fossils.

Although I can find no records of fossil Aralias very closely related to the species
from the Oligocene of Missoula, yet the present distribution of Aralia racemosa,
native to eastern North America, and closely allied species, such as A. cordata
Thunberg of Japan, and A. cachemirica Decaisne of the Himalayas, argues for a
Tertiary distribution of one or more ancestral forms of that type.

The genus Aralia now includes about thirty species of herbs and woody plants
ranging through temperate North America and Asia, and south from the latter
through the Malay Archipelago and into Australia. Many of the fossil species
so reported are perhaps not Aralia, but belong to other genera of that family or
even to other families. However, taking the reports as they stand at the present
time, there are numerous species of Aralia described from the Cretaceous, perhaps
sixty altogether, beginning in the upper part of the Lower Cretaceous in Portugal
(Albian) and the eastern United States, and becoming numerous and practically
cosmopolitan in the Upper Cretaceous. From the Eocene about twenty-five species
have been described, these being most numerous in the Fort Union of the western
United States and in the Paleocene of Belgium, while about an equal number have
been described from the Oligocene, all European, and more than half of these are
from the Sannoisian of southeastern France. About twenty-five species are recorded
from the Miocene, distributed through North America, Eurasia, and Australia. ^^

Various species of Aralia having been recorded for the western part of the
United States from the Eocene and Miocene, it is to be expected that Oligocene strata
would also yield them from that region and, even though no closely related forms
may have been recorded from the Eocene or Miocene of the West, yet the present

^8 See Berry, E. W. Aralia in American Paleobotany. Botanical Gazette, XXXVI, 1903, pp. 421-
428; idem, The Lower Eocene Floras of Southeastern North America, U. S. Geological Survey, Professional
Paper XCI, 1916, pp. 122-123.

^^RAJA"

426 MKMOIRS OF THE CARNEGIE MUSEUM.

distribution of Aralia racemosa and its allies would indicate that ancestral forms of
that species existed in the region, so that their occurrence in the Oligocene of the
Missoula district would be quite natural.

As the type specimen upon which this species rests I would designate the
specimen shown on Plate XXXIII, figs. 2 and 2a.

23. Vaccinimn palaeocorymbosum Jennings, sp. nov. (Plate XXXIII, Figs.
3 and 3a, Type, and 4, 4a.)

The type specimen consists of an impression of a leaf with the apex broken off.
The petiole is about 0.7 mm. in diameter, 4 mm. long, curved, uniform throughout
its length. The leaf-blade is ovate-lanceolate, widest at about the middle, where it is
1.8 mm. wide, apparently about 4.5-5 cm. long, rather bluntly tapering towards
the petiole, somewhat more narrowly tapering toward the apex; the margins
entire, slightly revolute. The midrib is rather strong, tapering above, the secon-
dary veins pinnate in probably about eight approximate pairs (six pairs are pre-
served in the specimen), these veins spreading at an angle of about 50° with the
midrib, curving upward towards the margin and finally looping successively with
branches from the lower side of the next vein above. The tertiary venation is
fine and rather indistinct, but towai^d the margin and along the lower side of the
lowermost pair of veins forming small narrow loops, while between the veins there
are a few tertiaries running across from one vein to the other at almost right angles
to them, the final meshes in the interior of the blade being rather small and indis-
tinct. There appears to be a very narrow decurrent flange along each side of the
petiole throughout its length.

In size, shape, and venation the specimen almost exactly matches leaves
which can be selected from the modern Vaccirmm corymbosum Linnaeus of swamps
and low woods from Maine, Quebec, and Minnesota to Virginia and Louisiana,
about the only noticeable difference being the somewhat larger angle of divergence
of the veins in the fossil specimen. In length of petiole, number and spacing of the
veins, narrow loops on the lower side of the lowest pair of veins, revolute margin,
margined petiole, etc., the resemblance is too close to be ignored. At first glance
the fossil suggests Quercus cinereoides Lesquereux^^ but in that species the base is
more rounded, the venation does not match that of the Missoula specimen very
closely, and there is little basis for beheving that an oak would have such a margined
petiole.

'' Lesquereux, Leo. The Tertiary Flora, U. S. Geological Survey of the Territories, VII, 1878,
p. 152, PI. 21, fig. 6.

JENNINGS: FOSSIL PLANTS FROM VOLCANIC ASH BEDS, WESTERN MONTANA. 427

The genus Vaccinium now contains about 130 species and it ranges from the
Arctic Circle to the mountains of the tropics, having its greatest development in
the Himalaya Mountains and in North America. Considerable doubt has been
expressed as to the correct identification of some of the fossil forms reported, but
it seems fairly certain that the genus is correctly ascribed to the Eocene, with three
or four species from Alaska and Colorado, while in western Europe in the Ohgocene
and, especially, in the Miocene, the genus was represented by a number of species,
so that the occurrence of Vaccinium in the Missoula region in the Oligocene would
not be unexpected.

428 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XXII.

Fig. 1. Buds of Equisetum sp. Enlarged two and one-half diameters.

Fig. 2. Equisetum insculptum Jennings. Type. Enlarged two and one-half
diameters.

Fig. 3. Sequoia Haydenii (Lesquereux) Cockerell. Natural size.

Fig. 3a. The upper part of the same specimen, enlarged two and one-half diameters.

Fig. 4. Sequoia Haydenii (Lesquereux) Cockerell. Enlarged about two diameters.
' Fig. 5. Sequoia Haydenii (Lesquereux) Cockerell. A young shoot enlarged
three and one-half diameters.

All photographed from specimens in the Carnegie Museum collected by Earl Doug-
lass from Montana. Figs. 1 and 2 from "Locality 139," Winston; Figs. 3-5 from
"Locality 196," near Missoula, Montana.

Memoirs Carnegie Museum, Vol. VIII.

Plate XXII,

Equiseluni and Sequoia.
(For explanation see opposite page.)

430 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XXHL

Fig. 1. Sequoia oblongifoKa Jennings. Type, enlarged about one and three-
fourths diameter.

Fig. la. Part of same branch, enlarged two and one-half diameters.

Fig. 2. Sabina lingucefolia (Lesquereux) Cockerell. Enlarged about two and
one-half diameters.

Fig. 3. Sequoia Haydenii (Lesquereux) Cockerell. Enlarged two and one-half
diameters.

Fig. 4. Sequoia Haydenii (Lesquereux) Cockerell. Cones, enlarged about three
and one-half diameters.

Fig. 5. Thuyopsis gracilis Heer. Enlarged about three and one-half diameters.

Fig. 6. Sequoia Haydenii (Lesquereux) Cockerell. Natural size.

Photographed from specimens in the Carnegie Museum collected by Earl Douglass
from "Locality 196," Missoula, Montana.

Memoirs Carnegie Museum, Vol. VIII.

Plate XXIII.

Sequoia, Sabina, and Thuyopsis,
(For explanation see opposite page.)

432 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XXIV.

Figs. 1, 2, and 3. Sequoia Haydenii (Lesquereux) Cockerell. Different types of
leaves of the same species.

Fig. 4. Betula multinervis Jennings.

Fig. 5. Ilex furcinervis Jennings.

Photographed from a specimen in the Carnegie Museum collected at Missoula,
Montana, from "Locality 196". About seven-eighths diameter.

Fig. 6. Populus Zaddachi Heer.

Fig. 7. Alnus microdontoides Jennings.

Fig. 8. Alnus Hollandiana Jennings.

Photographed from a specimen in the Carnegie Museum, collected at "Locality
196," Missoula, Montana, by Earl Douglass. About four-fifths diameter.

Memoirs Carnegie Museum, Vol, VIlI,

Plate XXIV.

Sequoia,- Betula, Ilex, Populus, and Alnus.
(For explanation see opposite page.)

434 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XXV.

Fig. 1. Populus Zaddachi Heer. Natural size.
Fig. 2. Populus Zaddachi Heer. About seven-eighths diameter.
Fig. 3. Alnus Hollandiana Jennings. Type. About seven-eighths diameter.
Photographed from specimens in the Carnegie Museum, collected at "Locality
196," Missoula, Montana, by Earl Douglass.

"w^'^^V,"

(Ih ^

436 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XXVI.

Fig. 1. Populus Zaddachi Heer. Natural size.

Fig. la. Middle left-hand margin of same specimen, enlarged two and one-half
diameters.

Fig. 2. Populus Zaddachi Heer. Natural size.

Fig. 3. Populus Zaddachi Heer. Base of leaf shown in Plate XXV, Fig. 1, enlarged
two and one-half diameters.

Fig. 4. Populus smilacifolia Newberry. Natural size.

Fig. 5. Populus Zaddachi Heer. Natural size.

Fig. 6. Populus Zaddachi Heer. Another leaf enlarged two and one-half diameters.

All photographed from specimens in the Carnegie Museum collected by Earl Doug-
lass at Missoula, Montana. — Figs. 1, 2, and 3 from "LocaUty 196;" Figs. 4, 5, and 6
from "Locality 165."

Memoirs Carnegie Museum, Vol. VIII,

Plate XXVI,

Populus Zaddachi and P. smilacifolia.
(For explanation see opposite page.)

438 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XXVII.

Fig. 1. Betula multinervis Jennings. About three-fifths diameter.

Fig. la. Same specimen, natural size. Type.

Fig. 16. Part of "la," enlarged two and one-half diameters.

Fig. Ic. Same as "lb," with the margin of the leaf drawn in.

Fig. 2. Betula multinervis Jennings. Cones, enlarged about two and one-half
diameters.

Fig. 3. Quercus approximata Jennings. Type. Natural size.
. Fig. 3a. Part of the same specimen, enlarged about two and one-half diameters.

All photographed from specimens in the Carnegie Museum collected by Earl Doug-
lass at Missoula, Montana. Figs. 1 and 3 from "Locality 196;" fig. 2 from "Locality
165."

Memoirs Carnegie Museum, Vol, VIII.

Plate XXVII.

Betula and Quercus.
(For explanation see opposite page.)

440 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XXVIII.

Fig. 1. Alnus Hollandiana Jennings.
Fig. 2. Betula multinervis Jennings.
Fig. 3. Quercus laurosimulans Jennings.

About two-thirds diameter. Photographed from a specimen in the Carnegie
Museum, collected by Earl Douglass at "Locality 196," Missoula, Montana.

Memoirs Carnegie Museum, Vol. VIII.

Plate XXVIII.

Alnus, Betula and Quercus.
(For explanation see opposite page.)

442 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XXIX.

Fig. 1. Juglans pentagona Jennings. Type. Natural size.

Fig. la. Part of same specimen, enlarged about two and one-half diameters.

Fig. 2. Juglans pentagona Jennings. Natural size.

Fig. 2a. Part of. the same specimen, enlarged about two and one-half diameters.

Fig. 3. Cyperacites sp. Enlarged two and one-half diameters.

Fig. 4. Typha Lesquereuxi Cockerell. Enlarged two and one-half diameters.

Photographed from specimens in the Carnegie Museum collected by Earl Douglass
from Missoula, Montana. Figs. 1, la, 2 and 2a from "Locality 165;" figs. 3 and 4
from "Locality 196."

Memoirs Carnegie Museum, Vol. VIII.

Plate XXIX.

Juglans, Cyperacites, and Typha.
(For explanation see opposite page.)

444 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XXX.

Fig. 1. Alnus Hollandiana Jennings. Type. Natural size.

Fig. la. Middle right-hand margin of same, enlarged two and one-half diameters.
Fig. 2. Alnus microdontoides Jennings. Type. Natural size.
Fig. 2a. Lower part of same specimen, enlarged two and one-half diameters.
Fig. 3. Alnus cones. Enlarged about two and one-half diameters.
Photographed from specimens in the Carnegie Museum collected at "Locality
196," Missoula, Montana, by Earl Douglass.

Memoirs Carnegie Museum, Vol. VIII.

Plate XXX.

Ahms HoUandiana and A. microdontoides.
(For explanation see opposite page.)

446 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XXXI.

Fig. L Quercus flexuosa 'Newberry. Natural size.

Fig. la. Part of the same specimen, enlarged about two and one-half diameters.

Fig. 2. Celastrus parvifolius Jennings. Type. Enlarged about two and one-half
diameters.

Fig. 2a. Same with the venation inked in.

Fig. 3. Quercus laurosimulans Jennings. Natural size.

Fig. 3a. Part of another leaf from the same place, enlarged about two and one-half
diameters.

All photographed from specimens in the Carnegie Museum collected by Earl Doug-
lass at Missoula, Montana. Fig. Ifrom "Locality 165"; figs. 2 and 3 from "Locality 196".

Memoirs Carnegie Museum, Vol. VIII.

Plate XXXI.

Quercus and Celastrus.
(For explanation see opposite page.)

448 MEMOIRS OF THE CARNEGIE MUSEUM.

EXPLANATION OF PLATE XXXII.

Fig. 1. Ficus (?) prunifolia Jennings. Type. Natural size.
Fig. la. Part of same specimen, enlarged about two and one-half diameters.
Fig. 2. Ilex furcinervis Jennings. Type. Natural size.

Fig. 2a. Upper part of same specimen, enlarged about two and one-half diameters.
Fig. 26. Same as 2a, but with the margin inked in.

Fig. 3. Acer oregonianum Knowlton. Enlarged about two and one-half diameters.

Photographed from specimens in the Carnegie Museum collected at Missoula,

Montana, by Earl Douglass; figs. 1 and 2 from " Locality 196 ", fig. 3 from " Locality 165 ".

Memoirs Carnegie Museum, Vol. VIII.

Plate XXXII.

Ficus, Ilex, and Acer.
(For explanation see opposite page.)

450 MEMOIES OF THE CARNEGIE MUSEUM.

e:?cplanation of plate xxxiii.

Fig. 1. Aralia longipetiolata Jennings. Natural size.

Fig. la. Same, but with the venation inked in.

Fig. 2. Aralia longipetiolata Jennings. Base of a larger leaf, natural size. Type.

Fig. 2a. Same, with the venation inked in.

Fig. 3. Vaccinium palceocorymhosum Jennings. Type. Natural size.

Fig. 3a. Same, enlarged about two and one-half diameters.

Fig. 4. Vaccinium palceocorymhosum Jennings. Natural size.

Fig. 4a. Same, enlarged about two and one-half diameters.

All photographed from specimens in the Carnegie Museum, collected by Earl
Douglass. Figs. 1 and 2 from " Locality 139", Winston, Montana; figs. 3 and 4 from
"Locality 196", Missoula, Montana.

Memoirs Carnegie Museum, Vol. Vlll.

Plate XXXIII,

Aralia and Vaccinium.
(For explanation see opposite page.)