gravel-covered terraces. Folio 179, U. S. Geol. Survey.
]
Beginning at the southern extremity of Maryland, we notice the
occurrence of remains of _Mammut americanum_ at or near St. Mary’s City.
Other remains of the same animal have been secured near St. Clements in
St. Mary’s County (p. 112). Both of the localities are situated on
territory mapped by Shattuck as Wicomico; but as remarked on page 112,
our knowledge of the conditions under which the fossils were found is
not sufficient to allow us to say more than that they belong to the
Pleistocene. The species existed from early to late Pleistocene and can
not be used to determine the age of the deposits.
Along Patuxent River, in Charles County, not far from Benedict, Cope
(Proc. Acad. Nat. Sci. Phila., 1867, p. 155) recognized jaws and teeth
of _Grison macrodon_ and of _Tagassu lenis_ (p. 220). Both are extinct
species.
According to Shattuck’s map of 1906, this region is covered by the
Talbot formation; but inasmuch as the species named were obtained from
pits furnishing Miocene marl, one can not be sure that they are not
older than the supposed Talbot. It would probably require a search in
the land records in order to determine exactly where the objects were
found. The presence of _Elephas primigenius_ suggests that this animal
had been pushed down here during one of the glacial stages.
Nearly a hundred years ago an elephant tooth (p. 154) was found
somewhere in Queen Anne County, but it would probably be now impossible
to determine the locality. In case the elephant tooth was found near
Chesapeake Bay, as is very probable, there is no record of any
Pleistocene vertebrate having been found in the central and eastern
parts of the eastern peninsula.
In the eastern peninsula remains of Pleistocene vertebrates have been
recorded from only two localities, Oxford Neck, Talbot County, and an
undetermined locality in Queen Anne County. From Oxford Neck, Cope
(Proc. Amer. Philos. Soc., vol. XI, 1869, p. 178) reported _Elephas
primigenius_, _E. columbi_, _Cervus canadensis_, _Odocoileus
virginianus_, _Chelydra serpentina_, and _Terrapene eurypygia_.
At Chesapeake Beach, William Palmer, of the U. S. National Museum,
discovered a few remains of Pleistocene vertebrates. One of these is a
tooth of an undetermined species of _Bison_, probably not the existing
one. Another species is probably _Equus leidyi_ (p. 189). Three teeth
appear to represent the peccary _Tagassu lenis_ (p. 220). In 1921, Dr.
Adolph H. Schultz, of the Johns Hopkins Medical School, presented to the
U. S. National Museum another specimen of _T. lenis_ which he had found
at Chesapeake Beach. Inasmuch as the fossils were picked up after having
fallen from their resting-place, it is impossible to say to which
formation they belonged. In the opinion of the writer, none of the three
species indicates a late Pleistocene time.
On the opposite side of the western peninsula, at Marshall Hall, Charles
County, there was found long ago a tooth which the writer refers to
_Equus leidyi_.
Coming north into the District of Columbia, we find recorded the
discovery of remains of horses and possibly at two different times.
According to Darton’s work (Folio 70, U. S. Geol. Surv.), there is some
later Columbia laid down along the route of the Chesapeake and Potomac
Canal above Georgetown. This would now doubtless be regarded as
belonging to the Talbot. It seems to follow that either the Talbot is
much older than has been supposed or that some of the extinct horses
continued on until a comparatively late time in the Pleistocene.
Within the limits of the city of Washington there has been found a tooth
of probably _Elephas primigenius_ at a depth of 35 feet, in the Wicomico
formation (see p. 178). On any theory of the origin of the terraces, the
presence of the tooth at that depth in the ground and at that elevation
appears to indicate a considerable geological age for the animal. To
what extent materials may have been washed down from the surrounding
higher land may be difficult to determine.
In Prince George County, near Mitchellville, have been found two teeth
of an extinct horse (p. 188). These are as yet unidentified. They are in
the U. S. National Museum, No. 8813.
Near Towson, in Baltimore County, a mastodon tooth has been found (p.
112); but beyond proving that there is at that locality some Pleistocene
deposit, it gives us little information.
In 1920 (Proc. U. S. Nat. Mus., vol. LVIII, pp. 96–109), the writer
described a collection of vertebrate fossils, collected in a cave or
fissure in limestone at Cavetown, Washington County, by anthropologists
from Phillips Academy, Andover, Massachusetts. The following is the list
of species that were found in the collection:
Crotalus horridus.
*Equus complicatus (p. 189).
*Equus giganteus? (p. 189).
*Mylohyus nasutus (p. 220).
*M. exortivus (p. 220).
*M. obtusidens, n. sp. (p. 220).
*Platygonus tetragonus? (p. 220).
*P. vetus? (p. 220).
*P. cumberlandensis (p. 220).
*Sangamona fugitiva.
Odocoileus virginianus (p. 231).
*Elephas columbi?
*Sciurus tenuidens, n. sp.
S. hudsonicus.
S. carolinensis.
Marmota monax.
Castor canadensis.
Ondatra zibethica.
Neotoma magister.
Microtus pennsylvanicus.
Erethizon dorsatum.
Sylvilagus floridanus.
Ursus americanus.
*Smilodontopsis mooreheadi.
Felis couguar.
Of the 22 species here recognized 12 are extinct. This large number of
itself indicates that their time of existence was not recent. Similarly,
the presence of 2 species of horses, several species of peccaries, and
of a saber-tooth tiger points to a rather ancient period. The writer
believes that the assemblage belongs to the Sangamon stage of the
Pleistocene.
[Illustration:
FIG. 17.—Generalized section across the Allegheny Valley at Parkers
Landing, West Virginia, showing various stages of erosion and valley
fill. U. S. Geol. Surv. Folio 178.
]
In Washington County, probably along Lane’s Creek, was found, in digging
a mill-race, the skull of a mastodon (p. 112). Further east, near Clear
Spring, and about a mile above the entrance of Conococheague Creek into
the Potomac, was discovered a tooth of a mastodon (p. 113). This had
been washed out of some deposit along this creek, probably not far away
from where it was found. As Stose has shown (Hancock Folio, No. 179, U.
S. Geol. Surv.), along the Potomac and its tributary streams there are
extensive Pleistocene deposits of sand and gravel, laid down when the
river was as much as 200 feet above its present level. It is probable
that such deposits date from the early Pleistocene (fig. 17). A more
important locality for Pleistocene vertebrates is that near
Corriganville, about 3 miles west of north of Cumberland, Maryland. The
cave is in Allegany County, west of Wills Creek and south of Jennings
Run, about 0.5 mile south of the village of Corriganville. An account of
this locality, with a list of the species determined up to that time,
has been published by Gidley (Proc. U. S. Nat. Mus., vol. XLVI, 1913,
pp. 93–102). In cutting through a spur of limestone in making a
railroad, at a depth of about 100 feet there was exposed a cave or
fissure which contained many bones and teeth. Gidley secured some
hundreds of specimens belonging to about 35 species. Unfortunately
nothing has been published which shows the relation of this cave to the
terraces which are found along Potomac River and its tributaries.
Through the kind offices of Mr. F. S. Rowe, welfare agent of the Western
Maryland Railway, the writer has received from the division engineer,
Mr. P. Cain, of Cumberland, a topographic map of Allegany County and a
profile of the road extending through the rock cut. From these it
appears that the level of the track, at the fissure, is 837 feet above
sea-level. This seems, therefore, to be considerably above the highest
terrace along the Potomac in that region. It is to be supposed that the
fissure was formed long before the animal remains accumulated in it.
In a paper published in 1920 (Proc. U. S. Nat. Mus., vol. LVII, pp.
651–678, plates LIV, LV, text-figs. 1–10) Gidley added to his former
list four species of peccaries, as follows: _Platygonus
cumberlandensis_, _P. intermedius_, _Mylohyus exortivus_ (all new), and
_M. pennsylvanicus_. In another communication he reported also a deer, a
wolverine, a beaver, a lynx, a badger, a marten, an eland, and a
crocodile or an alligator (Rep. Smithson. Inst. for 1918, pp. 281–287).
Many of the identifications are merely provisional.
_Provisional list of fossils found near Corriganville._
1. Alligator or Crocodylus sp. indet.
2. Blarina brevicauda?.
3. Vespertilio grandis.
4. Vespertilio sp. indet.
5. Myotis sp. indet.
6. Ursus vitabilis.
7. Ursus americanus?.
8. Canis armbrusteri.
9. Canis sp. indet.
10. Vulpes? sp. indet.
11. Mustela vison?.
12. Gulo luscus?.
13. Taxidea sp. indet.
14. Lynx sp. indet.
15. Mammut americanum.
16. Equus sp. indet. (p. 189).
17. Tapirus haysii? (p. 204).
18. Platygonus cumberlandensis (p. 220)
19. P. intermedius (p. 220).
20. P. vetus? (p. 220).
21. Mylohyus exortivus (p. 220).
22. M. pennsylvanicus (p. 220).
23. Odocoileus sp. indet.
24. Taurotragus americanus.
25. Ochotona princeps?.
26. Lepus americanus?.
27. Lepus sp. indet.
28. Sciurus hudsonicus.
29. Sciuropterus alpinus?.
30. Marmota monax?.
31. Castor sp. indet.
32. Neotoma sp. indet.
33. Microtus chrotorrhinus?.
34. Synaptomys borealis?.
35. Synaptomys sp. indet.
36. Peromyscus leucopus?.
37. Napæozapus sp. indet.
38. Erethizon sp. nov.
On account of the present unstudied condition of the collection, it is
difficult to reach conclusions that are satisfactory. It appears,
however, that there are at least 6 hitherto undescribed species,
one-fifth of the whole number. Another 6, if at all correctly
determined, indicate a wide removal from their ranges of the present
day. _Lepus americanus_ now lives well toward the north, coming down to
Saginaw, Michigan. _Ochotona princeps_ lives in the Rocky Mountains of
British America. _Synaptomys borealis_ is known only from the region
about Great Bear Lake, Mackenzie, Canada. _Microtus chrotorrhinus_ has
its habitat in Quebec and the northeastern United States. The species of
_Napæozapus_ are Canadian in their range, but descend to southeastern
Maryland and to North Carolina in the mountains. _Sciuropterus alpinus_
is found from Alaska to Hudson Bay, but descends on the Pacific coast to
southern California. This northern habitat of so many supposed species
suggests that the fissure received its contents during one of the
glacial stages, and this may be the case. However, it is not unlikely
that these species and some others are really undescribed ones. One may
reasonably expect to find in a fauna containing _Equus_ and _Tapirus_ a
much higher percentage of extinct species than Gidley has recorded.
The most remarkable member of the fauna is _Taurotragus americanus_, a
species closely related to the eland of southern Africa (Gidley, Smiths.
Misc. Coll., vol. LX, No. 27). Its presence in western Maryland gives a
vivid impression of the widely extended journey that some animals have
made from one continent to others. The same species has since been found
in collections made at Alton, Illinois (p. 339), and at Kimmswick,
Missouri (Proc. U. S. Nat. Mus., vol. LVIII, p. 113).
According to the author’s views, the fauna found at Cumberland, like
that of localities in western Virginia, belongs to a time somewhere
about the middle of the Pleistocene. Most of the species may be supposed
to have lived there during the warm Sangamon stage; others, as the
wolverine, at a somewhat earlier or later time when the climate was
cooler.
VIRGINIA.
For the student of Pleistocene vertebrate palæontology, as for the
geologist, Virginia may be divided into three physiographic regions, the
Coastal Plain, the Piedmont Plateau, and the Appalachian Mountains. The
line which divides the Coastal Plain from the Piedmont Plateau begins at
the southern boundary of the State, at about 77° 31′ longitude. The
towns on or not far from this nearly north-and-south line are Emporia,
Petersburg, Richmond, Hanover, and Fredericksburg. Near the latter the
line inclines slightly eastward and passes a few miles west of
Alexandria and Washington, D. C. The Coastal Plain is much less elevated
than the region west of it and consists of deposits of Mesozoic or
Cenozoic age, and much of it is covered by Pleistocene materials. The
Plateau region is elevated and consists mostly of Palæozoic rocks,
mostly metamorphosed into a crystalline condition. The Appalachian
region presents nearly parallel ranges of mountains and intervening
valleys.
For a knowledge of the Pleistocene geology of the Coastal Plain the
reader should consult Bulletin iv, 1912, of the Virginia Geological
Survey. The authors who discuss the physiography and geology of this
region are William B. Clark and Benjamin L. Miller. On pages 19 to 45
they present a very full bibliography of the geological literature
pertaining to this region. Additional valuable assistance may be
obtained from the various folios issued by the United States Geological
Survey, but unfortunately not many species of vertebrate animals have
been found on this Coastal Plain of Virginia.
In Bulletin IV, already mentioned, Clark and Miller recognize the
presence of three terraces belonging to the Pleistocene. To these are
given the names applied in Maryland and North Carolina to what are
regarded as equivalent terraces. The oldest of these, most elevated and
farthest from the coast, is the Sunderland; eastward of this lies the
Wicomico; the Talbot is the youngest and lowest and borders the coast.
Unfortunately, the geologists referred to did not map the areas occupied
individually or collectively by these terraces. They accept the theory
that these terraces were laid down in the sea. It is admitted,
nevertheless, that no marine fossils are found in deposits of the
Sunderland and Wicomico. In the Talbot, 26 species of marine mollusks
have been reported from Talbot deposits of the Dismal Swamp Canal, all
regarded as belonging to living species. It will be recollected that
Woolman (Proc. Acad. Nat. Sci. Phila., 1898, p. 414), in a study of
mollusks collected in the Dismal Swamp Canal, found 7 extinct species in
a collection of 49 species, equal to about 16 per cent. It is, however,
not unlikely that the collections had been dredged up from deeper
deposits.
In Bulletin V of the Virginia Geological Survey, on page 25, Sanford
stated that the Talbot had a width of 30 miles at the south. On
consulting Stephenson’s map of the superficial formations of the Coastal
Plain in North Carolina (North Carolina Geol. Surv., vol. III, plate
XIII) it will be seen that this corresponds quite exactly with the width
of the Pamlico formation at that line. For the writer’s views on the
terraces named the reader may consult page 346 on the geology of
Maryland.
On page 113 is recorded the discovery of a tooth of a mastodon in a
marsh near Disputanta, in Prince George’s County. Not enough is known
about the geology of the region to say more than that the deposit
belongs to the Pleistocene.
About 6 miles east of Williamsburg, a little more than 100 years ago,
remains which pretty certainly belonged to the genus _Mammut_ and
probably to the species _M. americanum_ (p. 113) were discovered, said
to have been found on the banks of York River; but by this was probably
meant the banks of the flood-plain. The bones were found in marsh mud
and were surrounded by roots of cypress trees. The adjacent bank was 20
feet higher than this level. The topographical map of the Williamsburg
Quadrangle shows that an abrupt rise of this amount is to be found only
about 10 miles away from the river. Whether the cypress roots were those
of trees that had grown within recent years or whether they were remains
of a Pleistocene forest, such as was exposed at Tappahannock, Essex
County (Bull. IV, p. 186), the writer does not know. The information at
hand about this case does not make it possible to pronounce on the
geological age of the mastodon.
On page 28 an account is given of the discovery of a skull of a walrus
on the Atlantic coast of Virginia, at Accomac. It had doubtless been
washed up by the sea from a Pleistocene deposit. It is easiest to
suppose that the walrus had been driven southward along the coast during
the Wisconsin glacial stage; but possibly this happened during an
earlier glacial time.
No vertebrate fossils of Pleistocene age appear to have come to light
anywhere on the Piedmont Plateau, and little or nothing is known about
its Pleistocene geology.
From the geological surveys we get little information about the
Pleistocene formations of the Appalachian region. At most, mention is
made of soils of undetermined age along the streams; and yet from this
region have been obtained a very considerable number of Pleistocene
vertebrates.
From Mr. Wyndham Robinson, of Abingdon, Washington County, the U. S.
National Museum received in 1869 a tooth of _Mammut americanum_ (p. 113)
and one of _Equus complicatus_ (p. 189). Nothing has been learned
regarding the conditions under which they were unearthed. The
horse-tooth points to an age preceding the Wisconsin drift.
From Saltville, in Smyth County, the following forms have been obtained:
Crocodylus sp. indet.
Megalonyx dissimilis (p. 34).
Equus sp. indet. (p. 190).
Odocoileus? sp. indet. (p. 231).
Cervalces sp. indet.
Bison sp. indet. (p. 259).
Mammut americanum (p. 113).
Elephas primigenius (p. 145).
That a crocodile should have lived in this region during the Pleistocene
is remarkable. _Megalonyx dissimilis_ is otherwise known only from
Natchez, Mississippi, from deposits which appear to be of about
Illinoian or Sangamon age. The horse-tooth points to about this time or
earlier, while the other species do not contradict this conclusion. The
astragalus referred to _Odocoileus_ probably belongs to some other
genus.
Mr. M. D. Mount sent to the U. S. National Museum remains of _Bison_ (p.
259), _Mammut americanum_ (p. 113), and _Elephas primigenius_ (p. 145).
These, he reported, had been found at a depth not greater than 8 feet in
excavating for the city reservoir. He has written that the valley of
Holston River at Saltville, within about 80 years, had been a lake, at
least at certain times of the year, and that the reservoir was excavated
at the margin of this low area.
Mr. O. A. Peterson (Ann. Carnegie Mus., vol. XI, 1917, pp. 469–474)
reported from this place the crocodile, the megalonyx, cervalces, the
supposed deer, the horse-tooth, and remains of mastodons. The bones were
found in a sink-hole, in a layer of coarse gravel, pebbles and
cobblestones, a fact indicating that a stream of some size had occupied
the place. Overlying this layer was one in which there were fragments of
large river shells. The bone layer appears to have been only about 4
feet from the surface. Peterson concluded that at the close of the
Pleistocene or later the remains had been moved and redeposited from
some place not far away, but this would not affect the geological age of
the fossils and it is evident that remains of vertebrates are widely
dispersed in that valley. All the species reported are extinct, but only
large forms were secured.
Professor Cope, probably in 1868, found the following 24 species. He did
not state the localities exactly, except that they were along New River,
in Wythe County. Two were on the land of Abraham Painter. The writer
applied to the surveyor of the county named and has been informed that
the farm which belonged to Abraham Painter is on New River, near the
town of Ivanhoe. The nomenclature of the species has been revised. The
species preceded by a dagger are extinct.
†Megalonyx jeffersonii (p. 34).
Castor fiber.
Neotoma floridana?
Marmota monax.
Peromyscus leucopus.
†Tamias lævidens.
†Sciurus panolius.
Sylvilagus floridanus.
Blarina sp. indet.
Vespertilio sp. indet.
†Tapirus haysii (p. 204).
†Equus complicatus? (p. 190).
†Mylohyus nasutus (p. 221).
Odocoileus virginianus (p. 231).
†Bison sp. indet. (p. 260).
†Ursus amplidens.
Procyon lotor.
Spilogale putorius.
†Myxophagus spelæus.
Crotalus sp. indet.
Amyda sp. indet.
Terrapene sp. indet.
Cryptobranchus sp. indet.
At least 9 of the 24 species are extinct. None of the recorded species
requires us to refer the deposit to early Pleistocene times. _Ursus
amplidens_ was described from the deposits at Natchez. This and _Tapirus
haysii_, _Equus complicatus_, and _Mylohyus nasutus_ point to middle
Pleistocene, apparently about to Illinoian or Sangamon times.
Cope reported that the teeth and bones were found in a cave breccia.
This consisted of a number of irregular masses which occupied
“depressions and short galleries” in the southeast side of a line of
hills. When those masses were excavated from their beds the floor and
roof of a portion of a cave were exposed, with the stalactites,
stalagmites, and usual incrustations. It would appear, therefore, that
at some time in the early Pleistocene or in the late Pliocene the caves
had been formed through the effect of streams of carbonated waters on
the limestone; that in some way the bones and teeth of the animals
listed above had got into the cave; that by a change in the amount or
character of the water the caves had gradually filled up; and that
afterwards the limestone which contained these caves had undergone great
erosion.
Further north, in the valley of Jackson River at Covington, there is
evidently a deposit of Pleistocene clay, for in it at a depth of 12 feet
was found a tooth of a mastodon (p. 114). Another mastodon tooth was
found near Hot Springs, at the head of Wilson Creek, in Bath County,
possibly in similar deposits (p. 114). In Augusta County an unidentified
species of horse (p. 190) and the peccary _Platygonus_ (p. 221) have
been discovered.
WEST VIRGINIA.
So far as the writer has learned, vertebrate remains belonging to the
Pleistocene have been found in West Virginia in only eight places and
only seven species are represented: _Mammut americanum_ (p. 115),
_Elephas_ sp. indet. (p. 179), _Equus niobrarensis?_ (p. 190), _Symbos
cavifrons_ (p. 254), _Megalonyx jeffersonii_ (p. 34), _Odocoileus
virginianus?_ (p. 231), and a peccary (p. 221). The horse appears to
indicate an early Pleistocene time, possibly pre-Kansan, but all the
other species continued from at least the Aftonian stage through to the
Late Wisconsin. The specimens, therefore, do not help us to determine
the age of the deposits in which they are found.
No part of the State lies within the glaciated area; hence, during the
whole of the Pleistocene epoch its surface was subjected to weathering
and to the erosion of running water. At times the streams built up
deposits on their beds. Later they deepened their channels and left a
part of their former deposits as terraces. At a still later time the
deposition and deepening may have been repeated, and as a result there
is sometimes a series of terraces one above another. The age of these
terraces and their origin have been the subjects of a good deal of
controversy.
In the Masontown-Uniontown Folio (U. S. Geol. Surv. No. 82), M. R.
Campbell has discussed the terraces along the Monongahela River, which
occur at an altitude of about 1,000 feet above sea-level and perhaps 150
feet above the present river. Also more than 100 feet above the present
river are old abandoned river channels which are now partially filled
up.