> » >

1

i

i'.'

JOURNAL

OF THE

SCIENTIFIC LABORATORIES

OF

DENISON UNIVERSITY

EDITED BY

KIRTLEY F. MATHER

VOLUME XIX- X
1919-1921 ,

GRANVILLE, OHIO

Published

April, September, 1919; May, 1920; September, 1921

CONTENTS OF VOLUME XIX

Foreword. By President Clark W. Chamberlain 1

1. Echinodermata of the Brassfield (Silurian) formation of Ohio. By

Aug. F. Foerste 3

2. America’s Advance in Potash Production. By W. C. Ebaugh 33

3. The Use of Outline Charts in Teaching Vertebrate Paleontology. By

Maurice G. Mehl 47

4. Some Factors in the Geographic Distribution of Petroleum. By Maurice

G. Mehl 55

5. Notes on Isotelus, Acrolichas, Calymene, and Encrinurus. By Aug. F.

Foerste 65

6. Some Suggested Experiments for the Graphic Recording of Speech Vibra-

tions. By Robert James Kellogg 83

7. The Manipulation of the Telescopic Alidade in Geologic Mapping. By

Kirtley F. Mather 97

8. The Importance of Drainage Area in Estimating the Possibilities . of

Petroleum Production from an Anticlinal Structure. By Kirtley F.
Mather and Maurice G. Mehl 143

9. Psychological Factors in Vocational Guidance. By Thomas A. Lewis 147

10. The Use of Models in the Interpretation of Data for Determining the

Structure of Bedded Rocks. By Maurice G. Mehl 157

11. Some Suggestions for Indicating Drilling Operations. By Maurice G.

Mehl 169

12. The Kimmswick and Plattin Limestones of Northeastern Missouri. By

Aug. F. Foerste 175

13. Education for Scholarship. By William E. Castle 225

14. The Cytology of the Sea-side Earwig, Anisolabis maritima Bon. Part 1.

By Sidney I. Kornhauser 234

15. Notes on Arctic Ordovician and Silurian Cephalopods. By Aug. F.

Foerste 247

16. Revolution vs. Evolution: The Paleontologist Renders His Verdict. By

Kirtley F. Mather 307

Subject and Author Index 325

\

iii

OF

Volume XIX Articles 1-4

Foreword. By President Clark W. Chamberlain

1. Echinodermata of the Brassfield (Silurian) formation of Ohio.

By Aug. F. Foerste 3

2. America’s Advance in Potash Production. By W. C. Ebaugh... 33

3. The Use of Outline Charts in Teaching Vertebrate Paleontology.

By Maurice G. Mehl 47

4. Some Factors in the Geographic Distribution of Petroleum. By

Maurice G. Mehl 55

GRANVILLE, OHIO, APRIL, 1919

Denison University Bulletins University Series Vol. XIX, No. 3

The University Bulletins are issued bi-monthly, and are entered at the Postoffice
at Granville as mail matter of the second class.

BULLETIN

OF THE

SCIENTIFIC LABORATORIES

OF

DENISON UNIVERSITY

Edited by

KIRTLEY F. MATHER

Permanent Secretary, Denison Scientific Association,
Granville, Ohio

The entire file of volumes 1 to 13 was destroyed by fire; no publications issued prior to
1907 are now available. Volumes 14 to date may be obtained from the editor at $2.00 per
volume, with the exception of volume 15, the price of which is $1.00. Separate parts, as listed
below, may be purchased at the prices indicated.

VOLUME 14

Articles 1-5, pp. 1-60; Nov., 1908 ; 10.50

Pre-Wisconsin drift in the Finger Lake Region of New York; F. Carney. 16 pp., 4 figs.

An esker group south of Dayton, Ohio; Earl R. Scheffel. 15 pp., 6 figs.

Wave-cut terraces in Keuka Valley, older than the recession stage of Wisconsin ice; F. Carney. 12 pp., 3 figs.

A form of outwash drift; F. Carney. 8 pp., 1 fig. ’

State geological surveys and practical geography; F. Carney. 6 pp.

Articles 6-10, pp. 61-188; April, 1909 SI. 00

Fossils from the Silurian formations of Tennessee, Indiana, and Kentucky;. Aug. F. Foerste. 56 pp., 4 plates.
Studies on Babbit and other alloys; 10 pp. J. A. Baker.

A statigraphical study of Mary Ann Township, Licking County, O. 28 pp., 15 figs. F. Carney.

Significance of drainage changes near Granville, Ohio; Earl R. Scheffel. 17 pp., 2 figs.

Age of the Licking Narrows; K. F. Mather. 13 pp., 5 figs.

Articles 11-16, pp. 189-287; June, 1909. SO. 75

A spectrometer for electromagnetic radiation; A. D. Cole. 10 pp., 6 figs.

The development of the idea of glacial erosion in America; F. Carney. 10 pp.

Preliminary notes on Cincinnatian fossils; Aug. F. Foerste. 20 pp., 1 plate.

Notes on Spondylomorum Quaternarium Ehrenb; M. E. Stickney. 5 pp., 1 plate.

The reaction to tactile stimuli and the development of the swimming movement in embryos of Diemyctylus torsus.

Eschschoitz; G. E. Coghill. 21 pp., 6 figs.

The raised beaches of the Berea, Cleveland, and Euclid sheets, Ohio. F. Carney. 25 pp., 5 figs.

Articles 17-18, pp. 289-442; November, 1909 SI. 00

Preliminary notes on Cincinnatian and Lexington fossils; Aug. F. Foerste. 45 pp.,' 5 plates.

The Pleistocene geology of the Moravia Quadrangle, New York; Frank Carney. 105 pp., 27 figs.

VOLUME 15

Article 1, pp. 1-100; March, 1910 , p.OO

Bulletin in commemoration of Clarence Luther Herrick.

FOREWORD

The Bulletin of the Scientific Laboratoeies was estab-
lished in 1885 by C. L. Herrick, who at that time filled the chair
of Geology and Natural History” at Denison. Two years later
it became the official organ of the Denison Scientific Association,
and has since been edited by the ^Termanent Secretary” of that
organization, a position occupied by various members of the
science staff. The funds to support the publication have been
provided by the Trustees of Denison in recognition of the fact
that it is the province of the University not only to dispense
information, but to enrich the store of human knowledge by
original research and independent investigation. The pages of
The Bulletin are open to contributions from the members and
past-members of the Denison Scientific Association; articles sub-
mitted for publication will be welcomed by the editor at any
time.

It is appropriate in this connection to acknowledge the in-
debtedness of the University and the Scientific Association to
Dr. Frank Carney, formerly Professor of Geology, who was editor
of The Bulletin from 1908 to 1917. Volumes 14 to 18, inclu-
sive, were issued under his direction ; they include more than half
the total number of pages published since 1885. His editorial
ability and facile pen did much to establish The Bulletin on a
high plane of scientific excellence and to bring it the recognition
in the realm of science, both in America and abroad, which it
now enjoys.

Clark W. Chamberlain.

1

ECHINODERMATA OF THE BRASSFIELD (SILURIAN)
FORMATION OF OHIO

AUG. F. FOERSTE

Relatively few echinoderms from the Upper or Albion di-
vision of the Medinan Silurian have hitherto been described.
From the Cataract strata of Ontario, Brockocystis clintonensis
(Parks), Brockocystis huronensis (Billings), Brockocystis tecumseth
(Billings), Mesopalaeaster (?) cataractensis Schuchert, and Meso-
palaeaster granti (Spencer) are known. From the Girardeau
of Missouri and Illinois, Cyclocystoides illinoisensis Miller and
Gurley, Glyptocrinus (?) fimhriatus Shumard, and Ptychocrinus
splendens (Miller) have been described. Deltacrinus alleni
(Rowley), Gissocrinus (?) prohlematicus Rowley, Glyptocrinus
inseparatus, with its varieties carinatus and pentagonus, all by
Rowley, have been described from the Edgewood of Missouri
and Illinois.

Although the Brassfield formation of Ohio, Indiana, and Ken-
tucky contains almost everywhere a considerable quantit of
coarsely crinoidal material, only one species, Clidochirus ameri-
canus Springer, has been listed by Bassler from this formation;
even this species, so far, has not been published.

This extreme poverty of echinoderm material from the Brass-
field formation may be easily understood on studying the lithol-
ogy of the rock. Where the echinoderm material is most
abundant the rock gives evidence of having been deposited by
strong and irregular currents. Cross-bedding is common. The
fragmental material is more or less rounded. Dismembered
plates and columnals of crinoids are common, fragments of col-
umns an inch or more in length are not infrequent, but rarely
are enough plates of the same calyx still found in their original
relative position to make possible even a generic identification.
The material described on the following pages represents all

3

4

AUG. F. FOERSTE

the writer ever found which is worthy of any attention. A close
discrimination of the calyx plates and of the fragments of columns
suggests that the Brassfield sea contained an abundance of
crinoidal life, representing many species. The trouble is not
with the lack of abundance, but with the dismembered condition
of this material.

Under the term crinoidal material, fragments of cystids fre-
quently are included. Pectinirhombs, such as exist among the
Glyptocystidae, occur in considerable numbers at some localities.
Starfish material is extremely rare. In a dismembered condition
it probably could not be recognized as such.

Fragments of calyces with a number of plates still in position
occur occasionally in the soft blue clay forming the top of the
Brassfield formation at the quarry northwest of the railroad
station at Centerville, and at the equivalent horizon in the
abandoned quarry at the Soldiers Home, west of Dayton, Ohio.
In the area southeast of Byron, about 8 miles northwest of Xenia,
Ohio, the weathered tpp of the Brassfield limestone not infre-
quently retains the basal portions of crinoid calyces, but usually
poorly preserved. Unfortunately the exposed rock surface is
relatively small; otherwise this area might give promise of more
crinoid material.

In the southern part of Ohio, in Highland and Adams counties,
Brockocystis nodosarius is represented by numerous fragments
in the lower third of the Brassfield formation; fairly preserved
thecae, however, were found only at one locality, about two
miles west of Peebles. Two of the starfish described from this
part of the state, on the following pages, were obtained near
the top of this Brockocystis zone.

In addition to the material from the Brassfield, there is de-
scribed on the following pages Clidochirus ulrichi, the only
crinoid found so far in the Dayton limestone. This limestone
lies immediately above the Brassfield formation and is correlated
with the Pentamerus limestone in the lower part of the Clinton
formation of New York. A poorly preserved specimen of Bo-
tryocrinus, from the Holophragma zone at the top of the Upper
or Lilley member of the West Union formation at Hillsboro.

ECHINODERMATA OF THE BRASSFIELD FORMATION

5

Ohio^ also has been added. This upper member of the West
Union formation is distinct faunally from the Lower or Bisher
member. The latter is correlated provisionally with the Iron-
dequoit member of the Clinton of New York, so that the upper
member may correspond to the lower part of the Lockport for-
mation of that state. The so-called Niagara shales of the earlier
reports of the Ohio Geological Survey, known as the Crab Orchard
shales in Kentucky, contain, in their upper layers, a fauna in-
cluding some of the characteristic species of the typical Clinton
of the central and more eastern parts of New York, such as
Liocalymene clintoni.

Several of the specimens here discussed present very unusual
features. The nodose aggregation of columnals at the top of
the stem of Brockocystis nodosarius is one of these. The frequent
coiling of the stem of an unknown crinoid, (plate I, fig. 6), with
the narrow end of the stem at the center, is another. An ances-
tral form of Myelodactylus is a third. On plate II (fig. 6) are
figured fragments of a crinoid which would be a Dimerocrinid
if it had sub-basal plates ; but the latter apparently do not occur.
On plate VII are presented several figures of an echinoderm
{Stereoaster) regarding which little is known at present beyond
the fact that it resembles a star-fish in appearance but not in
structure. It promises to be one of the anomalous forms of
which the relationship remains unknown, at least for the present.
Finally, on plates IV and V is figured a star-fish which evidently
diverges distinctly from typical forms of Mesopalaeaster.

Brockocystis nodosarius sp. nov.

Plate 7, figs. 1, 2, S, 5

Theca small, oblong in outline, 11 or 12 mm. long and 9 or
10 mm. wide. Pectinirhombs present on plates 1-5, 12-18,
14-15, and 10-15, but absent on plates 11-17; more or less dis-
crete along the suture which separates the two plates forming
each rhomb. The lower boundary of the pectinirhombs is more
strongly defined on plates 1 and 12 than is the corresponding
upper boundary of the same pectinirhombs on plates 5 and 18.

6

AUG. F. FOEKSTE

The number of stereom-folds in pectinirhomb 1-5 is 3 or 4; in
pectinirhomb 12-18, about 5 or 6; in pectinirhomb 14-15, about
7 or 8; and in pectinirhomb 10-15, about 4 or 5.

Prominent protuberances occupy the middle of all the plates
belonging to the first three rows. The protuberances of the
four basal plates project downward, beyond the top of the column,
for distances approaching or equalling one millimeter. Where
pectinirhombs are present, the latter encroach on the central
protuberances, and similar encroachment is noticed also in case
of the plates bordering on the anal area; the encroachment is
least in case of plate 7. In some specimens, low ridges connect
the protuberances of adjacent plates; in others they are absent.
In their present state of preservation the plates appear smooth.
Anal area apparently elliptical in form, about 3 mm. in height
and 2 mm. in width. None of the plates belonging to this area
are preserved in the specimens at hand.

Only traces of the food-groove system remain. The ambu-
lacra recline on the surface of the theca as in other Lepadocystinae,
In one specimen, one of the ambulacra passes along the upper
left margin of plate 17 to within one millimeter of the top angle
of plate 1 1 ; another ambulacrum reaches the upper part of plate
18, but does not extend nearer than one millimeter to the upper
margin of that part of the pectinirhomb which is present on this
plate. In the same manner, ambulacra reach only the top of
plates 19 and 15. This is true presumably also in case of plate
16, although this plate is not exposed in any specimen at hand.
There scarcely is room for more than two or three brachioles on
each side of each ambulacrum. These brachioles are at least
5 mm. long, and are directed upward. They are biserial dorsally,
the plates of the two series alternating. The length of these
dorsal plates equals or only slightly exceeds their width. The
ventral side of the brachioles is not exposed in any specimen
at hand but its probable appearance may be inferred from the
corresponding parts of Lepadocystis moorei, Meek, a closely re-
lated species occurring in the upper part of the Richmond group,
at Richmond, Indiana. In the latter species the covering plates
on the brachioles are more numerous than the dorsal plates; in

ECHINODERMATA OF THE BRASSFIELD FORMATION

7

outline they are long and linear, with their longer axes directed
at right angles to the length of the brachiole. The ambulacral
plates which remain attached to the theca of the species of
Brockocystis here under discussion appear to be of comparatively
large size and are relatively few in number.

The semilunate pore (gonopore) on plate 23 is distinct y de-
fined in the angle between the two ambulacra which extend to-
ward plates 17 and 18. A more minute pore (hydropore) may
be present directly beneath the center of the semilunate pore,
but is not distinctly defined. Plate 23 may be a double plate;
at least, a crack appears to pass through the center of the semi-
lunate pore.

The largest fragment of a column remaining attached to any
theca known is 20 mm. in length. In the more distal parts of
the column, for a length of 12 mm., the column is narrow, ranging
from two-thirds to a whole millimeter in width, the proximal
columnals being broader. In the prox'mal part of the column,
8 mm. in length, the columnals are collected into two groups,
of which the first is inversely pyriform, and the second is inversely
truncate-conical in form. The constituent columnals of each
group are anchylosed together, but the groups separate readily
from each other and from the remainder of the column. In this
separated condition the groups form characteristic fossil remains
easily identifiable generically, even in the absence of the theca.
This is true especially of the inversely pyriform groups. A
vertical section of one of these groups (fig. 5) shows a lumen
from three-fourths of a millimeter to a whole millimeter in width.
Along this lumen, the constrictions locating the inner parts of
the columnals appear equally spaced, six columnals occupying
a length of slightly more than 3 mm. Exteriorly, the marginal
parts of the constituent columnals of the inversely pyriform
groups rise, so that externally the lower three or four columnals
of each group appear distinctly longer than the upper three or
four columnals of the same group. The topmost columnal is
constricted in size to the width of the lowest columnal, and is
hidden in the base of the large depression indenting the top
of the group. To this hidden columnal is attached the second

8

AUG. F. FOEESTE

group of columnals, of which six columnals occupy a length of
about 2.3 mm. This second group also has a deep, wide depres-
sion at the top, as though the inner part of the body-cavity of
the tegmen were connected directly with the lumen. The upper
margin of this second group is overlapped by the descending
extensions of the protuberances on the basal plates of the theca.
If the proximal columnals are the youngest, then the second
group may be due merely to a rejuvenation of the process which
gave rise to the first group. When the upper margin of the first
group had attained such a size that it crowded upon the over-
lapping extensions of the basal thecal plates, a new series of
smaller columnal plates appears to have been started. It is
conceivable that stereom was added to the exterior of the col-
umnals after the more central parts already had been formed.

In the figured specimens, the surface of the thecal plates ap-
pears to be smooth; however, on many of the loose thecal plates,
evidently belonging to the same genus, the surface of the plates is
covered by a reticulated series of lines, similar to that shown
by Brockocystis tecumsethi (Billings) (plate III, fig. 1) from the
top of the Manitoulin dolomite, on Manitoulin island, in Ontario,
Canada. It is possible that there are two species of Brocko-
cystis in the Brassfield strata of Ohio, but if that be true, this
fact has not yet been definitely determined.

Locality and position. The specimens here figured were ob-
tained in the lower part of the Brassfield formation, beneath a
trestle along the railroad about two miles west of Peebles, Ohio.
They were in the upper part of the cherty layers which occur a
short distance above the base of the Brassfield formation in the
southern part of the state. The following section is exposed

beneath the trestle, in descending order:

feet.

Limestone, cherty nodules few 3

Limestone, in more massive beds, cherty nodules large and numerous . 3

Limestone, thinner bedded, cherty nodules small and few 2

Limestone, thin-bedded, no chert noticed 2.5

Creek level beneath tressle.

The following fossils were secured here, chiefly from the upper
half of strata here listed, which belong to the more cherty part

ECHINODERMATA OF THE BRASSFIELD FORMATION

9

of the section: Cyathophyllum facetum, Brockocystis nodosarius,
Hemitrypa ulrichi, Phaenopora multifida, Rhinopora verrucosa,
Hehertella daytonensis, Hehertella fausta, Orthis fiahellites, Pla-
tystrophia daytonensis, Leptaena rhomhoidalis, Plectambonites
transver sails, Strophonella daytonensis, Illaenus ambiguus, and
Phacops pulchellus.

At the quarry directly north of Lawshe, Ohio, the strata
equivalent to the cherty limestones listed above are underlaid
by several thinner bedded limestone layers containing Platy-
merella manniensis Foerste (Bull. Sci. Lab. Denison Univ.,
vol. 14, 1909, p. 70, pi. 1, figs. 1 A-D) and Plectambonites trans-
versalis. So far, this is the only locality known in Ohio, Indiana,
or Kentucky, at which Platymerella occurs.

The geographical range of Brockocystis nodosarius is limited
to the southern part of Ohio. No specimens have been found
so far in the neighboring parts of Kentucky. It occurs at numer-
ous localities in Adams and Highland counties, in Ohio, and has
been found also at Sharpsville, in the southern angle of Clinton
county. The most western locality at which it has been noted
is the quarry in the creek bottom, a short distance east of Dan-
ville. Eastward, its range appears limited only by the extent
of the outcrops.

An unknown Brassfield Lepadocystid

Plate II, fig. 2

Detached plates of some Lepadocystid are common within
5 feet of the top of the Brassfield formation at the exposure along
the electric railroad where it follows the Dayton and Troy pike,
about a mile northwest of Cowlesville, in the southern part of
Miami County. Many of these plates bear pectinirhombs, and
occasionally one of them bears the double pectinirhomb charac-
teristic of plate 15 in the genera Brockocystis and Lepadocystis.
In some of the plates the halves of the pectinirhombs are broad
but of small height; they lie near the margin of the plates; the
inner margin of the pectinirhomb is gently concave, the outer
margin consists of two sides meeting at a very obtuse angle at

10

AUG. F. FOERSTE

the middle; both the outer and inner margins are delimited by
a narrow linear elevation. On other plates the halves of the
pectinirhombs lie farther from the margins of the plates, and the
outer margin as well as the inner margin of the pectinirhomb is
more lunate in outline. There is no evidence of central nodose
elevations on any of these plates, nor of any prominent radiating
sculpture.

The associated columns are circular in cross-section, with a
circular lumen. The columnals are of very short height, 15
occurring in a length of 5 mm. in a column 6 mm. in diameter.
The ends of these columnals are finely and radiately striated.
There is no tendency toward the grouping of these columnals
into more or less nodose or pyriform sections.

Both the dissociated plates and the associated columns probab-
ly belong to some undescribed species from among the Lepado-
cystinae, possibly to Brockocystis.

Similar plates and columns occur at the same horizon at various
localities in the southern part of Miami and Clark counties and
in the northern halves of Miami and Greene counties. No at-
tempt has been made to determine their area of distribution.
They are described here chiefly to call attention to the presence
of additional cystids in the Brassfield formation in the hope that
more perfect specimens may be found.

Coiled “crinoid” stem

Plate /, fig, 6; plate II, figs. 5 A-C

1884, American Naturalist, p. 57

A coiled column of some echinoderm, obtained in the upper
part of the Brassfield limestone in the Soldiers Home quarry,
west of Dayton, Ohio, was figured by the writer thirty-five years
ago. This column was at least 11.5 cm. long, but, on the sup-
position that almost all of the second largest volution is missing,
an original length of at least 21 cm. is probable. This column
increased from a diameter of 1.5 mm., at the smaller end of the
column, to a diameter of 6.5 mm. in a length of 7.7 cm. Beyond

ECHINODERMATA OF THE BRASSFIELD FORMATION

11

this point, the volutions were not preserved continuously. The
columnals were approximately circular, with a moderately
irregular margin.

A second coiled column, (plate I, fig. 6) evidently belonging
to the same species, was found recently, also in the upper part
of the Brassfield limestone, 1 mile northeast of Wilberforce, and
miles northeast of Xenia, Ohio. The exposure occurs east
of the road to Clifton, on the northern side of the road to the
Eastpoint school, along the upper part of the creek bed. Here
large dissociated columnals of the same species are very common
in the ferruginous layer, 2| feet below the base of the Dayton
limestone. The coiled column found here has a length of 16.4
cm. About three and a third volutions are preserved. Meas-
uring from the larger toward the smaller end, the first volution
has a length of 9.1 cm. ; the second, of 5 cm. ; the third, of 1.8 cm. ;
and the remainder, of 0.5 cm. At the larger extremity the col-
umnals have a diameter of 8 mm. ; at a distance of 7.8 cm. from
the larger end this diameter is 6.5 mm.; 7.7 cm. from the second
point the diameter equals 2.7 mm.; at its smallest extremity
the diameter is only slightly more than 1.5 mm. These measure-
ments suggest that the rate of decrease in the diameter of
the column is more rapid nearer the smaller extremity. The
margins of the columnals are badly weather worn but apparently
were approximately circular, with a moderately irregular margin.

The columnals are not of equal thickness. This is more
readily noticeable in the larger columnals. Frequently narrower
and thinner columnals alternate with thicker ones in such a
manner as to suggest intercalation subsequent to the develop-
ment of the larger columnals. This is a familiar feature among
various genera of crinoids. Since both the larger and the inter-
calated smaller columnals become thinner toward the lumen,
it is evident that arftculation is secured by still smaller columnals,
not readily seen in a view of the exterior of the complete column,
though frequently still attached to the disarticulated larger
columnals. The articulating surface of these articulating col-
umnals, and the corresponding surface of that part of the larger
columnals which surrounds the lumen, is radiately striated.

12

AUG. F. FOERSTE

. Similar coiled crinoid stems, evidently belonging to the same
species, have been found recently also at the large quarry north-
west of the railroad station, at Centre ville, Ohio.

Disjointed columnals (plate II, figs. 5 A-C) are very common
near the top of the Brassfield limestone, both in Ohio and in
eastern Kentucky. The maximum size attained by these col-
umnals is 25 mm. Most of them do not exceed 15 mm. in
width. Columnals between 15 and 25 mm. in width usually
are almost circular in outline with little evidence of crenulation.
Smaller columnals frequently are crenulated; some of the smaller
specimens are pentagonally lobed; when they are both lobed
and crenulate they frequently are very pretty and attract at-
tention as beads. In both of the coiled columns found so far
the outlines of the columnals are moderately crenulated but not
pentagonal in outline. Whether the more or less pentagonal
columnals represent a different species is unknown at present.
On many of these columnals it is possible to recognize five equally
distant, radiating, narrow color lines suggesting former sutures,
and indicating the pentamerid origin of the columnals.

The radiating striae on the articulating surface of the artic-
ulating columnals, described above, number 10 or 11 in a dis-
tance of 1 mm. They correspond closely in appearance with
the striae on the articulating surfaces at the base of the calyces
of the two species of crinoids described next. Both of these
species occur at the top of the Brassfield formation in the area
southeast of Byron, about 7 miles northwest of Xenia, Ohio.
Both are found at about the same horizon as the coiled stem
described from the top of the Brassfield hmestone, 1 mile north-
east of Wilberforce. Both are very similar in the size and the
outline of the first three circles of plates, and apparently even
in the degree of development of the very low but broad radiating
ridges ornamenting the plates. They differ chiefly, as far as
the calyces are known at present, in the shape of one of the
plates in the first or basal circle. In the first species here de-
scribed, (plate II, figs. 6 A-E) the top of one of the basal plates
is truncated, indicating the position of the anal side of the calyx.
In the second species all of the plates belonging to the first circle

E'CHINODEKMATA OF THE BRASSFIELD FORMATION

13

are pentagonal in form, and there is no indication of the anal
side in the part of the calyx known at present. Moreover, in
the second species, (plate VI, figs. 2 A-D) the surface ornamen-
tation consists of numerous parallel lines which are perpendic-
ular to the adjacent sides. The surface of the first species appears
to have been relatively smooth.

At present there is no means of determining whether the coiled
crinoid stems described here belong to either of these two species,
but the latter are the only forms known of such size as to suggest
the possibility of such a relationship.

Dimerocrinus (?) vagans sp. nov.

Plate II, figs, 6 A-E

Basals five, four of them pentagonal in outline, the fifth trun-
cated and supporting the anal x plate. The inner margin of
the circle of five basals is formed by the aperture connecting
the lumen of the stem with the body-cavity of the calyx. The
articulating surface for the attachment of the column is formed
by a circular ridge which encloses the proximal parts of the five
basals. The area thus enclosed is deeply concave. The crest
of the circular ridge traversing the basals is marked by numer-
ous, very fine, short lines arranged as though radiating from the
center of the circle. About 9 or 10 of these lines occur in a
width of 1 mm. No infrabasals are present in any of the speci-
mens found. In the specimen represented by figure 6 A the
margin of the articulating surface appears to be slightly scal-
lopped, somewhat as in figure 6D. If this could be confirmed
by well preserved specimens it would indicate the former pres-
ence of infrabasals. The presence of such infrabasals would
relegate our specimens to the Dimerocrinidae. As a matter of
fact, however, the former presence of infrabasals remains ex-
tremely doubtful, in which case the calyces here described would
not fit into any of the families of Crinoidea as now defined. Fig-
ure 6D is intended to indicate the possible relationship of these
calyces to the Dimerocrinidae.

14

AUG. F. FOEESTE

Judging from the fragments at hand, the basal part of the
calyx must have been comparatively flat as far outward as the
distal parts of the first interradials. Beyond the latter, the
sides of the calyx probably curved more or less rapidly upward,
producing a semi-globose form, flattened beneath, possibly
similar to that of Lyriocrinus. The lateral diameter of the
calyx must have equalled at least 60 mm. Obscure lines of
elevation traverse the plates somewhat as indicated in figure 6E.

Locality and ^position. Within 2| feet from the top of the
Brassfield limestone, 7 miles northwest of Xenia, Ohio. The
locality may be reached by going 1 mile east from Byron, then
1 mile south, to a shallow wet-weather stream exposure, on the
east side of the pike.

Base of calyx of unknown species of crinoid

Plate VI, figs, 2 A-D

At the same locality and horizon as the preceding species,
southeast of Byron, Ohio, occur the basal parts of the calyces
of a second species of crinoid, closely resembling the preceding
species in general appearance. The chief difference consists in
the fact that there is no differentiation of the anal side among
the basals, nor, apparently, among the radials and first inter-
radials, as far as the latter are preserved. All of the basals are
pentagonal in outline. The articulating surface for the attach-
ment of the column is similar to that of the preceding species.
If infrabasals ever were present, this fact remains to be proved.
The plates of the calyx are ornamented by close-set parallel
striae arranged in groups which are perpendicular to the adjacent
suture lines. In intermediate parts of the plates these striae
tend to break up into series of granules which are elongated more
or less in the direction of the neighboring striae. The general
form of the calyx probably was similar to that of Lyriocrinus
melissa Hall.

This second species appears so closely similar to the preceding
species here described, as far as preserved, that there is a possibility
of both belonging to the same family of crinoids. All the Dimero-

ECHINODERMATA OF THE BRASSFIELD FORMATION

15

crinidae, however, have an anal plate following a truncated
basal. In the present state of our knowledge of these calyces
any attempt to assign them to some definite family of crinoids
would be merely guesswork. The chief reason for calling atten-
tion to them is the fact that this and the preceding species
possibly may belong to the interesting coiled crinoid stems de-
scribed earlier in this paper. They are of sufficient size, have
a large enough lumen, the surface markings on the area of attach-
ment are similar, the specimens occur at the same horizon, and
in sufficient numbers at least to suggest a possible former
connection.

Figure 41 on plate VIII of vol. 3, Bull. Sci. Lab. Denison Uni-
versity, probably represents another specimen of the same species
as that here described. This figure is reprinted on plate 27
of vol. 7 of the Ohio Geological Survey, published in 1895. The
specimen was obtained at Reed’s hill, east of Fairfield, Ohio.

Clidochirus sp.

Plate VII j fig, 1

Species named by Springer in his Monograph of the Crinoidea Flexibilia, now in

press.

Infrabasals low, not exceeding 1 mm. in height, presumably
three although the complete circuit is not preserved in the speci-
men at hand; exposed surface erect, taking part in the calyx
wall and having about the same slope as that of the basals. The
right posterior infrabasal is broadly triangulate above. The
anterior and right anterior infrabasals are merged into a single
plate with a gently concave upper surface, bearing the right
anterior basal. Although the left anterior and left posterior
basals are only imperfectly preserved, it is assumed that these
plates also are merged into a single plate with a gently concave
upper margin, bearing the left posterior basal. The height of
the basals only slightly exceeds their width, excepting in the
case of the posterior basal which is a little higher and bears the
anal x plate on its upper right margin. This anal x plate is in
contact with the upper left margin of the radial at the base of

16

AUG. F. FOERSTE

the right posterior arm, and also with the left side of the first
costal and the lower left side of the second costal belonging to
the same arm; on the other side, this anal x plate is in contact
with the right side of the radial and the lower right side of the
first costal belonging to the left posterior arm. Each arm be-
gins with the radial followed by two costals, except in the case
of the right posterior arm where the presence of the '^radianal
in its primitive position under the right posterior radial, resting
on the basals’^ (Springer) produces the appearance of a radial
followed by three costals. The distichals in each arm-branch
number four, excepting in the case of the left branch of the left
posterior arm, where only three distichals occur. Most of the
subsequent branches expose six palmars, but the tips are in-
folded and are not well exposed so that the number of palmars
may equal seven or eight, or even may exceed that number.
The arms all are closely adjoined laterally.

Locality and position. In the clayey layers at the top of the
Brassfield formation, in the large quarry half a mile northeast
of the village of Centerville, Ohio.

Remarks. This species is characterized by its elongate form.
The sides of the calyx diverge at an angle of about 40 degrees
as far as the axillary costals. The series of distichals are more
nearly vertical, and, beyond the distichals, the series of palmars
are incurved. The ratio of the length to the width of the entire
crown is about 17 to 10.

Figure 39 on plate 8, vol. 3, Bull. Sci. Lab. Denison Univer-
sity, republished on plate 27 of vol. 7 of the Ohio Geological
Survey in 1895, represents a specimen obtained in the soft clay
at the top of the Brassfield formation, at the Centerville quarry.
In the original publication it was described as Ichthyocrinus
sp.; a fragment of the calyx. This reference to Ichthyocrinus
is based solely upon the close lateral abutting of the arms, and
the general aspect of the fragment. At the base of the frag-
ment is an axillary costal, followed by two arm-branches, each
with three distichals; this is followed by four arm-branches, the
two median ones with five palmars, the right-hand branch with
eleven palmars; beyond the palmars, branching takes place

ECHINODERMATA OF THE BRASSFIELD FORMATION

17

again. A part of another arm forms the right side of the frag-
ment; the distichals of the left branch are followed by two arm
branches, of which the left one has nine palmars, and the right
one has five palmars. In the case of each arm, the two median
arm branches following the distichals are broader and shorter;
the two exterior arm branches of the same set are narrower and
longer, recalling in this respect CUdochirus of which it may be
another species.

Clidochirus ulrichi sp. nov.

Plate II, figs. 1 A, B; text figure 1

Infrabasals three, 1.3 mm. in height, exposed surface sloping
at the same angle as the basals. Basals, 2.5 mm. in height.
Radials, except in the case of the right posterior arm, 2 mm. in
height. Radials, except in the case of the right posterior arm,
followed by two costals, of which the first has a height of 1.7 mm.
while the second or axillary costal has a height of about 2 mm.
at its middle. The right posterior arm appears to consist of a
radial followed by three costals, and the designations first,
second, and third or axillary costal are used in connection with
this arm in the immediately following parts of this description.
The radianal is relatively long and narrow, narrowing especially
toward the base; it lines the left margin of the radial at the base
of the right posterior arm for its entire length and borders also
on the lower left margin of the first costal of this arm. The
anal x plate borders on the lower left margin of the second costal
and lines the left margin of the first costal of the right posterior
arm; on its left side it barely reaches the lower right corner of
the second or axillary costal, but borders on the right side of
both the first costal and the radial. In all arms there are four
distichals in each vertical series. Each arm terminates with
four series of palmars, of which, in the specimen at hand, the
two outer series consist of about eleven or twelve palmars, while
the two inner series appear to be shorter and to consist of only
eight or nine palmars.

18

AUG. F, FOERSTE

Column slender, about 1.8 mm. in width. Columnals vary-
ing between 0.4 and 0.5 mm. in length, frequently alternating
with much shorter intercalated columnals.

Locality and 'position. In the upper part of the Dayton lime-
stone, at the base of the Niagaran division of the Silurian, along
the side of the Germantown pike, southeast of the Soldiers Home,
west of Dayton, Ohio. Named in honor of E. 0. Ulrich, whose

Fig. 1. Clidochirus ulrichi sp. nov. Diagram of Plates, with Anal Side

AT Top

investigations have enriched every department of Palaeozoic
Paleontology.

Remarks. If, in accordance with the investigation of Springer,
the lowest plate in the right posterior arm series be interpreted
as the ‘hadianal in its primitive position under the right posterior
radial,” then the first costal of the preceding description becomes
the radial, and the right posterior arm is credited with only two,

ECHINODERMATA OF THE BRASSFIELD FORMATION

19

in place of three costals. In that case it is evident that the
specimen here described has two radianal plates, the primitive
radianal plate at the base of the right posterior arm and the
secondary radianal plate w^edged in between the primitive radi-
anal and the anal x plates. It is not known to what extent this
secondary radianal plate will be found to be a constant feature
in this species.

Compared with the Brassfield species of Clidochirus described
and figured by Springer, and also described in this paper, the
crown of Clidochirus ulrichi is elliptical ovate rather than in-
versely conical in form. The sides of the calyx are more di-
vergent and the greatest width of the crown is near mid-length.
All of the arm plates are relatively shorter and wider, especially
in case of the costals and distichals.

Myelodactylus (Eomyelodactylus) rotundatus

sub-gen. et sp. nov.

Plate I, fig. 8; plate II, fig. 3

Fragment of column, coiled, about 115 mm. in length, broken
off where the reversal of curvature begins, possibly within 25
mm. of the base of the crown. The greater diameter of the stem,
measured from the convex to the concave side of its curvature,
equals 2.25 mm, throughout almost the entire length of the frag-
ment, but at a distance of 5 mm. from the beginning of its re-
versal in curvature this diameter diminishes rapidly and is
reduced to 1.4 mm. at the broken end. It probably continued
to diminish in size gradually toward the crown. The diameter
at right angles to the one just discussed is a little less, thus pro-
ducing a slightly elliptical cross-section.

The length of the columnals varies. The first three columnals
at the broken end, where reversal begins, occupy a length of 1.5
mm.; the next three, 1.9 mm.; the next three, 2.0 mpi.; the next
three, 2.3 mm. ; then the length of the columnals remains constant
until a point opposite the broken end has been reached. Then
the length diminishes to three columnals in 1.8 mm., remains

20

AUG. F. FOERSTE

constant for about one-third of a volution, and diminishes to
three columnals in 1.5 mm. at the end of the last third of a
volution.

Throughout by far the greater part of the length of the column
the latter has been split in two along a plane parallel to the plane
of curvature. This exposes a darkened line, never more than
three-tenths of a millimeter in width, which evidently locates
the lumen. The latter is distinctly nearer the convex side of
the curvature of the column, and, in transverse sections of the
stem, is seen to be wider in a direction at right angles to the
plane of curvature. Under a lens it appears possible to detect
four additional planes, indicated by slightly darker coloring,
suggesting original pentamerism (plate II, fig. 3) with the un-
paired segment on the convex side of curvature of the column.
Why this unpaired segment should split so smoothly along its
middle is unknown, but the immediately opposite suture evi-
dently is the one along which the stem should split most readily.

There is no conclusive evidence of the presence of two rows
of cirri, nor of points of attachment for the latter, although
vague traces of short cirri appear to be present at one point.

Locality and position. Holotype found up stream from Silver
Springs, on the head waters of Caesars Creek, 4f miles south-
east of Xenia, Ohio. The locality is over a mile and a half up
stream from the Xenia-Wilmington pike. Here it occurs in
the upper half of the Brassfield limestone, associated with the
following fauna: Cyathophyllum facetus, Haly sites catenularia,
Hemitrypa ulrichi, Chasmatopora angulata, Clathropora frondosa
clintonensis, Phaenopora expansa, Ptilodictya expansa, Ptilo-
dictya americana, Pachydictya hifurcata, Pachydictya ohesa,
Rhinopora verrucosa^ Rhipidomella hyhrida, Platystrophia day-
tonensis, Leptaena rhomhoidalis, Brachyprion moderately convex,
Strophonella daytonensis, Strophonella hanoverensis, Atrypa mar-
ginalis, Cyclonema daytonense, Illaenus ambiguus, Illaenus day-
tonensis, Proetus determinatus, and Encrinurus thresheri.

Remarks. The reversal of curvature at the broken end of this
column is indicated by the distinctly greater length of the last
three columnals along the inner side of the coil. This suggests

ECHINODERMATA OF THE BRASSFIELD FORMATION

21

the reference of the column to Myelodactylus or Herpetocrinus,
two terms regarded at present as applying to the same genus.
In hitherto described species of this genus the column is dis-
tinctly concave longitudinally along the inner side of curvature
of that part of the column which bears the two rows of cirri. In
the Brassfield species here described there is no trace of such a
concave indenting of the outline of the columnals along the inner
curvature of the column, and, hence, the Brassfield specimen
is regarded as representing an earlier stage of development than
typical Myelodactylus, and the subgeneric term Eomyelodactylus
is here proposed with this Brassfield specimen as a type. In
American strata, Myelodactylus is not known in strata earlier
than the Rochester shale of New York and the Laurel limestone
of Indiana, another species being known from the Waldron of
Indiana, and a fourth from the Racine of Bridgeport, Illinois.

Botryocrinus sp.

Plate II, figs, 4 A, B

Calyx imperfect, more or less distorted by obliquely vertical
compression, and with only parts of the upper margin of several
of the infrabasals preserved. Basals, radials, radianal, and
anal x plates similar in outline and general form to Botryocrinus
polyxo Hall, from the Waldron shale of Indiana, but the latter
attains a much larger size, and the facets for the reception of the
arms are more vertically inclined. The maximum width of the
calyx here described is about 13 mm. Although probably rep-
resenting a new species, not enough remains of the specimen at
hand to reveal any distinguishing characteristics.

Locality and position. In the Holophragma zone at the top
of the Upper or Lilley division of the West Union formation,
in the Zink or Corporation quarry, in the eastern part of Hills-
boro, Ohio.

22

AUG. F. FOEKSTE

Mesopalaeaster (Hemipalaeaster) schucherti sp, nov.

Plates IV, V

Measurements: disk imperfectly preserved; its radius, meas-
ured from the center to the nearest part of the interbrachial arc,
estimated as between 10 and 12.5 mm. Length of rays, meas-
ured from the basal radial to the tip, 25 mm.; distance from
center of disk to tip of rays estimated as between 34 and 36.5 mm.
Ratio of the longer radius, from the center of the disk to the tip
of the rays, compared with the shorter radius, to the nearest
part of the interbrachial arc, between 3.4 and 3, probably nearer
the latter.

Abactinally, the disk is limited by an interrupted circle of
large plates, consisting of the basal supramarginals (S, in figure
on plate V), the dorsal interradials (i), and five plates (r), one
at the base of each ray, interpreted as basal radials. The basal
supramarginals tend to be pentagonal in outline and the dorsal
interradials are more or less broadly triangular or rhomboidal
triangular, with the blunted apex of the triangle directed toward
the suture between the basal supramarginals. In the accompa-
nying figure, these outlines are best indicated in the interbrach-
ial areas between rays I and V. In the other interbrachial arcs,
the dorsal interradials tend to have a shallow indentation on
the proximal margin. In the arc between rays I and V, the
proximal halves of the basal supramarginals are separated by
a rhomboidal triagonal area (m) filled by a material distinctly
darker than that of the abactinal plates, and, although occupy-
ing the position of a madreporite, its interpretation as such is
extremely doubtful, especially in view of the absence of distinct
radial striations. Similar dark material appears to occur in
the sutures between some of the other plates on the abactinal
surface. The plates interpreted as basal radials (r) are broadly
pentagonal, with the very obtuse apex directed toward the distal
end of the rays. In the accompanying figure, its outline is best
shown on ray V, its blunt apex being directed slightly down-
ward and toward the right, the plate being slightly displaced.

ECHINODERMATA OF THE BRASSFIELD FORMATION 23

Between the basal radials and the nearest basal supramarginals
there are one or two narrow, transversely elongated plates. The
integument of the abactinal part of the disk apparently broke
loose from the proximal end of rays III and IV, and contracted
toward the opposite side of the disk, causing the disk plates on
that side to be thrust more or less beneath the ring of plates
forming the margin. Possibly the circular plate, marked C in
the accompanying figure, is the centro-dorsal. Several plates
of nearly equal size are slightly reniform in outline, but their
original location is uncertain. Apparently, the remaining plates
of the disk were of smaller size, some of them much smaller than
others, but nothing can be said of their arrangement. In the
accompanying figure the larger cross indicates the center of the
disk as suggested by the present arrangement of the ring of
marginal plates. The smaller cross gives another possible po-
sition for this center, if shrinkage of the integument be supposed
to have caused a moderate lateral spreading of that part of the
marginal ring which remained intact.

Abactinal area of rays consisting distally of three columns of
plates, the two columns of supramarginals and the intermediate
column of radials. The radials here are distinctly smaller than
the supramarginals, forming with the latter transverse groups,
each consisting of three plates, the spaces in the angles between
two consecutive radials and the two adjoining supramarginals,
on each side, being apparently vacant. The distal margin of
each radial tends to overlap slightly the proximal margin of the
adjoining radial. The proximal margin of the supramarginals
tends to overlap slightly the distal part of the two adjoining
supramarginals, while that part of the lateral margin which
adjoins the neighboring radial is slightly pointed and tends to
overlap the margin of this radial. That part of the ray in which
the column of the radials is distinctly defined forms about seven-
tenths of its length. Proximally, for the remaining three-tenths
of its length, it is difficult to determine with certainty which
plates are to be regarded as belonging to the column of radials.
In the accompanying figure, on plate V the outlines of the radials,
in the distal parts of the rays, and also the outlines of the sup-

24

AUG. F. FOEKSTE

posed radials, in the proximal parts of the rays, have been dark-
ened. Only a small portion of these supposed radials is seen
in certain cases, due to hiding beneath the overlapping accessory
plates, intervening between the columns of radials and supra-
marginals. Proximally, there appear to be two columns of the
accessory plates. These plates are ovate in outline, the more
or less pointed ends being directed diagonally both toward the
distant end of the ray and toward the radials, more or less over-
lapping the latter. The original arrangement of plates appears
to have been disturbed least in the proximal parts of ray II; in
ray V, the basal supramarginal and the two adjacent plates of
the same series have been crowded inward, permitting only the
tips of several of the adjacent accessory plates to show; other-
wise the plates of the proximal part of this ray are but little
disturbed.

The number of supramarginals in each column, exclusive of
the basal supramarginal, apparently varies between 17 and 19,
of which the distal two or three are much smaller than those
immediately preceding. The most distal accessory plates occur
at the side of the fifth, sixth, or seventh of the supramarginal
plates, not counting the basal plate of the series. It is diffi-
cult to interpret the distal parts of rays II and IV without
assuming the presence of supernumerary plates in the radial
series, one or two supernumerary plates occurring also in three
of the supramarginal series.

All of the rays expose some of the inframarginals, the longest
continuous series being exposed on the sinistral side of ray I and
on both sides of ray II. The number of these inframarginals
appears to be slightly greater than that of the supramarginals,
so that while they alternate with the latter proximally, they are
even with them laterally in more distant parts of the ray, and
become alternate .again farther on. The inframarginals are
larger in size then the supramarginals at least in the distal parts
of the rays. They form the margins of the rays and extend
from the abactinal to the actinal side of the rays, and are seen
best on lateral view. No ambital or accessory plates occur be-
tween the columns of supramarginals and that part of the series

ECHINODERMATA OF THE BRASSFIELD FORMATION

25

of inframarginals which is exposed immediately adjacent in case
of any of the rays. In ray II, the inframarginals are in contact
with supramarginals as near as the sixth supramarginal, not
counting the basal plate of this series. In ray I, they are in con-
tact as near as the fifth supramarginal. On the sinistral side
of ray V, the nearest inframarginal alternates with the sides of
the fourth and fifth supramarginal. This suggests that if any
ambitals exist the latter must be restricted to more proximal
parts than any here exposed and that their number must be small.

The actinal side of the rays is exposed by the tip of ray V (see
figure VB on plate IV) for a length of 15 mm. The inframarginal
plates form the sides of the rays and the adambulacral plates
form two additional rows, one on each side of the ambulacral
groove. In number, the adambulacrals appear to equal the
inframarginals, and to be directly opposite the latter, but they
are of less width. The plates seen at the bottom of the ambu-
lacral groove are interpreted as ambulacral plates, but they are
not exposed well enough to permit of accurate description.

The surface of the plates, where unweathered, is minutely
granular, about four granules occurring in a distance of half a
millimeter.

Locality and formation. Five and a half miles west of Hills-
boro, Ohio, at a quarry reached by going from Fairview cross-
roads half a mile east and then three-quarters of a mile south-
ward, to the southern side of the head-waters of a small stream.
Here, the specimen described, a holotype, was found in the thin-
ner-bedded layers at the top of the quarry, associated with
Brockocystis nodosarius, Hallopora magnopora, Orthis flahellites,
Strophonella daytonensis, and Plectambonites transver satis. These
thin-bedded hmestone layers occur II J feet above the base of
the quarry. The base is formed by the more massive cherty
layers which occur a short distance above the base of the Brass-
field formation. Named in honor of Prof. Charles Schuchert,
in recognition of his many services to American Paleontology.

Remarks. The most striking feature of Mesopalaeaster s chuck-
erti consists in the radial plates forming a distinctly recogniz-
able series only along the more distal parts of the rays, and in

26

AUG. F. FOERSTE

the radial accessory plates being confined to the proximal parts
of the rays. In the more proximal parts of the rays it is im-
possible to pick out, with any degree of confidence, those plates
which are to be regarded as belonging to the radial series. The
nearer accessory plates either equal or exceed the radials in size,
and the latter either are partially covered or are more or less
displaced, so that they can not be identified as radials. While
not in the direct line of descent from Hudsonaster to Palaeaster,
this species indicates how Palaeaster may have originated by the
introduction of radial accessory plates and by the displacement
of the radials, the latter diminishing in size and finally disappear-
ing altogether distally.

It is evident that the genus Mesopalaeaster will be broken up
into various subgenera or genera as the species at present referred
to this genus become better known. The beginning has been
made by W. K. Spencer, who founds the new genus Caractacaster
on the Ordovician species Palaeaster caractaci Gregory, from the
Caradoc sandstone of Wales and of the Welsh border, character-
izing this genus by the presence of a continuous series of radials,
bordered on each side by a column of small radial accessory
plates which extends the entire length of the rays. For Meso-
palaeaster schucherti the subgeneric name Hemipalaeaster is pro-
posed, in view of the partial loss of a distinct series of radials, in
the proximal parts of the rays.

Schuchertia magna sp. nov.

Plate VI, fig, 1

Measurements. Radius of the disk, from its center to the
nearest part of the interbrachial arcs, 13 mm. Radius from the
center of the disk to the tip of the rays, 33 mm.; longer radius
about 2.5 times the length of the shorter radius.

Rays separated by large interbrachial arcs, narrowing rapidly
near the base, so as not to exceed 7 mm. in width at a distance
of 14 mm. from the tip; narrowing thence more gradually and
terminating rather bluntly.

ECHINODERMATA OF THE BRASSFIELD FORMATION

27

Abactinal area composed of numerous small plates. These
plates are very small near the tips of the rays and gradually
increase in size toward the disk, numerous plates on the disk
equalling 2 mm. in diameter. Nothing is known of the arrange-
ment of the plates except along the distal halves of the rays
where the plates are aligned in slightly oblique rows, as indicated
on rays A and B of the accompanying figure. Apparently five
or six of these rows occupied the width of the ray between 6 and
12 mm. from its tip. In the present state of preservation of the
specimen, the larger plates, on and near the disk, appear to be
irregularly interspersed with smaller plates. In the accompany-
ing figure, the larger plates are shown best on the left side of the
disk, between rays B and D.

Nothing definite is known of the surface of the plates, but a
few of them present the appearance of having been strongly
elevated at the middle into a prominent node.

Locality and position. The holotype was found about 5| miles
east of West Union, l| miles east of the Stone Church, where
the road crosses a small creek. Here the specimen was found
in the Brassfield limestone at the top of a small fall immediately
beneath the bridge, 30 feet below the base of the Dayton lime-
stone, at about the same horizon as the holotype of Mesopalae-
aster schucherti, although the latter was found miles west of
Hillsboro, Ohio.

Remarks. This specimen is of interest chiefly on account of
its occurrence in the Brassfield formation. At the time of its
discovery it appeared scarcely worth collecting. In outline it
closely resembles Schuchertia laxata Schuchert, but it is distinctly
larger and the plates on the disk appear to have been much more
irregular in size. If these plates were strongly nodose centrally,
this alone would be sufficient to distinguish it from the few spe-
cies of Schuchertia hitherto described.

The possibility of the plates being nodose centrally is sug-
gested by an anomalous specimen (fig. 7 on plate II) found,
associated with Brockocystis nodosarius, in the lower part of the
Brassfield formation, on a hill-crest a mile northeast of the center
of Manchester, Ohio. It is not known even that this specimen

28

AUG. F. FOERSTE

is part of a starfish, but if the nodose projections were removed
the plates would at least be similar in size and irregularity. The
larger of these plates are 2 mm. in width and the central nodose
projections are slightly over 1 mm. in width. Smaller plates
have correspondingly narrower projections. All plates are of
about the same thickness, about 0.8 mm., and the nodose eleva-
tions vary from a little over 1 mm. on the larger plates to about
0.6 mm. on the smaller ones. The width of the nodose elevations
is slightly greater at the top than at mid-length, and they may
have served as supports for spines.

Stereoaster squamosus sp. nov.

Plate VII, figs. 2 A, B, C

In its present state, the echinoderm here figured and described
resembles a starfish, and as such it is here described, although
structurally differing from all of the three major subdivisions
of the Palaeozoic Stelleroidea so far proposed — the Asteroidea,
Auluroidea, and Ophiuroidea.

Rays five, slender and gradually tapering, separated by dis-
tinct interbrachial arcs. The radius of the disk, from the center
of the disk to the interbrachial arcs, varies from 4.5 to 5 ihm.
None of the rays is preserved as far as its tip, but from such parts
as are preserved it is estimated that the radius from the center
of the disk to the tip of the rays equals about 18 or 19 mm. In
two of the interbrachial arcs the outline of the disk is moderately
convex rather than concave.

Only the actinal side of the specimen is exposed, but this side
of the specimen appears considerably worn so that almost all
of the plates actually exposed undoubtedly belong to the
abactinal part of the integumentary skeleton, only the inner sur-
faces of the abactinal plates being visible in most cases.

In the interbrachial area between rays I and V, as designated
on the accompanying figures, there is a broad, flat, scale-like
plate. Between this plate and the center of the disk, the bevelled-
off inner margins of at least four additional similar plates are
exposed. These plates overlap each other in such a manner

ECHINODERMATA OF THE BRASSFIELD FORMATION

29

that in each case the slope is from the upper, distal margin to-
ward the lower, proximal margin of the plate, forming an angle
of about 15 degrees with the horizontal plane of the specimen.
The surfaces of contact between these plates are finely striated
in a direction perpendicular to their inner margins, similar to
the striations on the inner surfaces of contact on some of the
larger scales of some of the Ordovician Agelacrinidae. In the
specimen here described these plates evidently were closely ar-
ticulated, and probably were held rigidly together, or were only
slightly movable.

In the interbrachial arc between rays I and II, and also be-
tween rays IV and V, there are several plates of which those
near rays I and V are shorter, while those near rays II and IV
are longer, in a radial direction. When viewed from the interior
of the disk, these plates or series of plates tend to slope in the
same direction as those between rays I and V, already described.

Large, flat, scale-like plates are present also between rays II
and III, and between rays III and IV. These also are finely
striated in a direction from their distal toward their proximal
margins, along their surfaces of contact. They slope somewhat
as the interbrachial plates between rays I and V, rising laterally
toward rays II and IV, and inclined more or less downward to-
ward ray III.

Mr. Austin H. Clark, of the United States National Museum,
kindly showed the writer various Ophiuroidea with more or less
overlapping scale-like plates, but in these Ophiuroidea the sym-
metry was plainly radial, while in the specimen here described
the symmetry seems more bilateral, as far as the arrangement
of the scales of the disk are concerned. Unfortunately the upper
surface of the disk is not visible. . On the basis of at least partial
bilateral symmetry, the interbrachial arc between rays I and V
is regarded as the posterior part of the disk.

The outlines of the inner surfaces of the abactinal plates of’
the rays are exposed best in case of ray IV. As here exposed,
the plates are irregular in size, form, and arrangement; there
appears to be no arrangement in longitudinal series, correspond-
ing to the radials, marginals, and inframarginals among the

30

AUG. F. FOERSTE

Stelleroidea. In its present state of preservation, the most
striking feature of this ray is the irregular series of short vertical
pores along the anterior side of the concave depression traversing
the actinal side of this ray longitudinally. These pores vary
from 0.25 to 0.33 mm. in depth, and tend to occur in pairs, the
members of each pair being less than 0.5 mm. apart, or sometimes
so close together that two pores are included in the same general
depression, appearing as separate pores only at the bottom of
the larger elliptical pore formed by their union.

A similar irregular series of vertical pores occurs along the
anterior side of the longitudinal depression following the actinal
side of ray II. Pores are not seen on the proximal parts of ray
III, but on the distal part several pores occur along the middle
of the longitudinal depression there visible. Vertical pores exist
also along the middle of the deep depression following the actinal
side of ray V. In the case of ray I, that part of the longitudinal
depression which might show pores is over-arched by other
plates, not seen on the other rays, probably because not pre-
served there. No explanation for the presence of these pores
can be offered. They appear closed at their inner extremities,
and apparently bear no relation to the podial canals among the
Auluroidea. At first they were regarded merely as borings,
subsequent to the death of the animal, but in that case there
appears to be no reason why their presence should be confined
practically to definite parts along the longitudinal depressions
following the actinal side of the specimen. The depression
marked a in figure 2C on plate VI accompanying this paper
probably represents an ordinary boring, and is quite different
in size and depth from the pores just described. Moreover,
there is no appearance of pairing in this case.

The plates forming the abactinal side of the specimen,’ and
these are almost the only plates here exposed, are so thick, and
are so closely appressed at the sutures, that they must have
been almost immovable. The thickness of the plates varies
between 0.6 mm. to almost an entire millimeter, and may exceed
this amount in some parts of the specimen, nearer the disk,
where measurements, in the present state of exposure of the
specimen, are impossible.

ECHINODERMATA OF THE BRASSFIELD FORMATION

31

In the case of ray I, what is regarded as the ambulacral groove
is overarched, at least proximally, by a number of small plates
not seen on the other rays. The outlines of only a few of these
small plates can be distinguished, and these do not suggest any
analogy with the ambulacral and adambulacral plates among
the Asteroidea. The arching plates, except at the proximal end
of the ray, appear to be thin, and appear to sag readily into the
ambulacral groove. Similar over-arching plates may have ex-
isted formerly over the proximal ends of the ambulacral grooves
of all of the other rays, but, in the present worn condition of the
specimen no trace of these plates can be detected. The proximal
half of ray III at present shows no trace of the ambulacral groove,
probably on account of weathering, but the longitudinal de-
pression formed by this groove is retained on the distal half of
the ray, and here the short vertical pores already described occur
along the central part of this depression.

Locality and position. Associated with Dimer ocrinus (?)
vagans, within 2| feet from the top of the Brassfield limestone,
at a locality reached by going from Byron, Ohio, 1 mile east and
then 1 mile southeast. The exposure occurs in a shallow wet-
weather stream bed, east of the road. In a direct line this ex-
posure is less than seven miles northwest of Xenia.

Remarks. The affinities of this species among the Echinoder-
mata are highly problematical. The arm structure does not
resemble even remotely that of the Ophiuroidea or Auluroidea.
The entire absence of any structure resembling ambulacrals and
adambulacrals excludes it from the Asteroidea, even from the
Cryptozonia division of the Asteroidea. The specimen here
figured and described is the only one found in many years of
collecting, and there seems no prospect of securing additional
illuminative material in the near future; hence its present
publication.

The excellent photographs forming the basis of the accompa-
nying figures were prepared by Dr. Herrick E. Wilson, of the
U. S. National Museum.

PLATE I

Figs. 1-5. Brockocystis nodosarius sp. nov. The pectinirhomb on plates
12-18 is seen in figures 1, 2, and 3; the last two of these figures show also the pec-
tinirhomb on plates 1-5; in each figure the anal area is on the right, the two plates
bordering on the left side of this area being included in the figure. Figures 1
and 3 show traces of the brachioles. The pectinirhombs on plates 14-15 and 10-
15 are shown by figure 4; the anal area is included in the lower left hand corner
of the figure. The pyriform enlargement of the column, a short distance below
its top, is shown in figure 5, presenting both a horizontal and a vertical section,
indicating the origin of this enlargement from the coalescence of a number of
columnals. All figures enlarged 2.7 diameters. From 2 miles west of Peebles,
Ohio; Brassfield formation.

Fig. 6. Coiled crinoid stem. From Brassfield formation, 1 mile northeast of
Wilberforce, Ohio. For illustrations of separate columnals see plate II, figures
5A, B, C.

Fig. 7. Brockocystis tecumseth (Billings). Enlargements of the top of the
column, due to coalescence of several of the columnals. Three lateral views,
showing variation in outline; one specimen viewed from the top, showing area
of articulation. Cataract formation; half a mile east of Ice Lake, on road from
Gore Bay to Kagawong, on Manitoulin Island. Shown in contrast with similar
enlargements of the column in Brockocystis nodosarius.

Fig. 8. Eomyelodactylus rotundatus sp. nov. Coiled column, terminating
at the center at the point where reversa of curvature took place. In by far the
greater part of its length this column has been split in half, and only the split
surface is seen, exposing the lumen. See plate II, figure 3, for a cross-section of
this column. Brassfield formation; nearly 5 miles southeast of Xenia, Ohio.

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE I

FOERSTE: OHIO BRASSFIELD ECHINODERMATA

PLATE II

Fig. 1. Clidochirus ulrichi sp. nov. A. Enlarged view of calyx and arms,
showing the anal side. B. Same specimen, with column attached. Dayton
limestone; southeast of Soldiers’ Home, west of Dayton, Ohio.

Fig. 2. Lepadocystid plate. Single plate of unknown species of Lepadocystid.
Brassfield formation; 1 mile northwest of Cowlesville, Ohio.

Fig. 3. Eomyelodactylus rotundatus sp. nov. Cross-section of column of
specimen represented by figure 8, plate 1.

Fig. 4. Botryocrinus sp. A. Lateral view of calyx, anal side. B. Top view
of same specimen. Holophragma zone at top of Upper or Lilley division of West
Union formation; Zink quarry in eastern margin of Hillsboro, Ohio.

Fig. 5. Crinoid columnals. Columnals of same species as that forming the
coiled column illustrated by figure 6, plate I. A and C from Soldiers’ Home
quarry, west of Dayton; B from Centerville quarry, Ohio.

Fig. 6. Dimerocrinus (?) vagans sp. nov. A, B, and C. Fragments of the base
of calyces, all with anal side at top of figure; A, B, exterior views; C, view from
interior side of calyx. D. An attempt at a restoration of the basal part of the
calyx, based on various specimens. E. Figure indicating the direction of the
radiating lines ornamenting the plates. Brassfield formation; about H miles
southeast of Byron, Ohio.

Fig. 7. Echinoderm plates. Numerous small plates of an echinoderm, each
plate ornamented by a small central abruptly elevated protuberance. For de-
scription, see paragraph following remarks on Schuchertia magna.

Bulletin Scientific Laboratories Denison University Vol. XIX

FOERSTE: OHIO BRASSFIELD ECHINODERMATA

PLATE III

Fig. 1. Brockocystis lecumseth (Billings). Basal view of theca, showing
large lumen at area of attachment, the pectinirhomb on plates 1-5, and the reticu-
lated surface of the plates. For additional illustrations of the same specimen,
see Bull. Sci. Lab. Denison Univ., vol. 17, pi. V., figs. 2A, B, C; the character-
istic globular or pyriform aggregations of columnals of th’s species are figured
on plate I of the present paper. From Manitoulin Island, east of Ice Lake, on
the road from Gore Bay to Kagawong.

Fig. 2. Undetermined crinoid. Basal part of calyx of some unknown crinoid,
with five infrabasals. Top of Brassfield formation; southeast of Byron, Ohio.

Fig. 3. A Platycrinid (?). Calyx and arms apparently belonging to the Platy-
crinidae; however, the margins of the plates are not defined clearly enough for
accurate determination. Fro r the soft clay at the top of the Brassfield formation
at Centerville, Ohio. Platycrinus corporiculus liingueberg (Bull. Buffalo Soc.
Nat. Sci., vol. 5, 1886, p. 12, pi. I, fig. 9) from the Rochester shale at Lockport,
N. Y., is a somewhat similar dubious form.

Fig. 4. Cyathocrinus (?) sp. Parts of a crinoid with very thick plates, possi-
bly a Cyathocrinus . A, a radial followed by two costals, the axillary costal sup-
porting two arm-branches, of which only the left one is well preserved. The
latter has three distichals, and again only the left branch of the succeeding arm-
branch is well preserved. B, top of column with 2 very thick infrabasals still
attached, also one of the basals. From the soft clay at the top of the Brassfield
formation, at the Centerville quarry, Ohio. In vol. 3, Bull. Sci. Lab. Denison
Univ., on plate 8, figure 42 presents one of the radials of this species, and figure
43 probably represents one of the basals. Figure 44 may be one of the axillary
plates of the arm system. All of these earlier figured specimens were obtained
from the soft clay at the top of the Brassfield formation, at Soldiers’ Home, west
of Dayton, Ohio.

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE III

FOERSTE: OHIO BRASSFIELD ECHiNODERMATA

PLATE IV

llemipalaeaster scliucherti sp. nov. Abactinal side of an almost entire speci-
men, enlarged about 2.1 diameters. Before complete burial, the margin of the
disc appears to have rotted away from the proximal parts of rays III and IV, and
to have shrunk away from the latter. In collecting the specimen, the tip of ray
V broke off, and the impression left by this ray in the top of the limestone is shown
by figure VA; the actinal side of this tip is represented by figure VB. The
lateral margins of this second figure are formed by the inframarginals; the
other two rows of conspicuous plates are the adambulacrals. For comments
on the remainder of the specimen see the descriptive material accompanying
the diagrammatic indications on plate V. From the top layers in the quarry,
5^ miles west of Hillsboro, Ohio, reached by going from Fairview cross-roads
half a mile east, then three-quarters of a mile south, crossing the headwaters
of a small stream to a quarry in the lower half of the Brassfield formation.

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE IV

FOERSTE: OHIO BRASSFIELD ECHINODERMATA

PLATE V

Hemipalaeaster schucherti sp. nov. The rays are numbered from I to V. In
each ray, the radial plates are indicated by darkening their outlines. In the
distal parts of the rays this may be done with some accuracy; in the more proxi-
mal parts this is all guess-work. The basal supramarginals are indicated by S,
and from these plates the remaining supramarginals may be traced readily as
far as the tips of the rays. The inframarginals are well seen on the left side of
ray I, and on both sides of ray II, along the more distal two-thirds of the rays.
The dorsal interradials are indicated by i. The plates indicated by r may cor-
respond to the basal radials of other species, but this is very doubtful. The
former extent of the disc of this specimen is indicated by the broken circle. The
two plates which are marked i, and which are enclosed by this broken circle,
resemble the dorsal interradials in outline and are believed to have been located
originally at the points on the circle with which these plates are connected by
dotted lines. The original center of the disc probably was located near one of
the two small crosses. The plate marked C may correspond to the centrodorsal
of other species, but this is highly problematical. Moreover, the correct inter-
pretation of the apparent opening toward the right of plate C is prevented by its
poor state of preservation. If the plate marked M is the madreporite, it does
not resemble the corresponding one in Palaeaster niagarensis. The arrange-
ment and general appearance of the basal supramarginals and of the dorsal inter-
radials, however, is similar.

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE V

:fe^|

FOERSTE: OHIO BRASSFIELD ECHINODERM ATA

PLATE VI

Fig. L Schuchertia magna sp. nov. A poorly preserved specimen, enlarged
1.7 diameters, photographed under water so as to bring out the individual plates.
Most of these have been displaced. Near the tip of ray A most of the plates still
occupy their original relative position; this is true also of some of the plates on
the distal halves of rays B and E. Those of the central part of the specimen
evidently have been much displaced. The specimen is valuable chiefly in pre-
senting the general form and size of the species. About 5^ miles east of West
Union, miles east of the Stone Church, where the pike crosses a small creek.
Here the specimen was found in the Brassfield limestone, 30 feet below the base
of the Dayton limestone, at the top of the limestone exposure immediately
beneath the bridge. The horizon is regarded as approximately the same as
that of H emipalaeaster schucherti, although the latter was found over 5 miles
west of Hillsboro, Ohio.

Fig. 2. Unknown crinoid. A, base of calyx with traces of the low ridges
ornamenting the plates; in the figure these traces are emphasized. B, a second
specimen, preserving better the articulating surface for the attachment of the
column, C, several additional plates. D, one of the plates, preserving the sur-
face ornamentation. From the area a mile and a half southeast of Byron, Ohio,
at the top of the Brassfield formation. Figure 41 on plate 8, vol. 3, Bull. Sci. Lab.
Denison Univ., appears to represent the same species. The same figure is seen
on plate 27 of vol. 7 of the Ohio Geological Survey, published in 1895.

Bulletin Scientific Laboratories Denison University Vol. XIX

Xj.3

ZA 2.B

PLATE VI

Ki.3

2C

FOERSTE: OHIO BRASSFIELD ECHINODERMATA

PLATE VII

Fig. 1. Ciidochiriis sp. Species described by Springer. Anal side of calyx
with arms attached. From the soft clay at the top of the Brassfield formation
at the quarry northwest of the railroad station at Centerville, Ohio.

Fig. 2. Stereoaster squamosus sp. nov. A, entire specimen, actinal side.
B, the greater part of the same specimen enlarged. ^ C, a part of one of the arms
enlarged still further. The arms are numbered with Roman numerals. The
arrows in figure 2C point to depressions within which the pores are seen to occur
in pairs; the letter a in the same figure points to a large pit for which there ap-
pears no structural reason. The overlapping of the plates within the central
area is seen best within the lower, lefthand side of this area, and near the basal
parts of ray II in figure 2B. There is no evidence of system in the arrangement
of the plates, such as would be expected among the Stelleroidea.

Bulletin Scientific Laboratories Denison University Vol. XiX

PLATE VII

FOERSTE: OHIO BRASSFIELD ECHINODERMATA

AMERICA’S ADVANCE IN POTASH PRODUCTION^

W. C. EBAUGH
INTRODUCTION

In a paper presented early in 1917,2 it was pointed out that
the world faced an emergency of greatest consequence, due to
its inability to get potash for agricultural and industrial uses,
and the hope was expressed that the Great War might lead to
cheap potash, just as the Napoleonic wars of the preceding
century had led to cheap soda. Events of the last two years
apparently justify the belief that this hope has turned to fact,
and that economic independence, so far as potash is concerned,
has been won by a victory no less remarkable in its way than
that achieved by arms.

The antitheses of war are striking. Men, women and chil-
dren have pain, mutilation, starvation and death forced upon
them, are torn loose from their abodes and possessions, and
scattered broadcast as refugees ; yet never are bravery, coopera-
tive action, fellowship of all classes, and self-forgetfulness more
in evidence. Science and industry run amuck, labor on a gi-
gantic scale is turned from constructive to* destructive work,
the normal markets and trade routes are closed, and wastage
is enormous; yet inventive genius, medical skill, sanitation, con-
servation, substitution of new raw materials for those no longer
available, and the introduction of new methods of manufacture
and distribution come to a nation’s relief. National hate, greed,
duplicity, rapacity, ruthlessness and cruelty find their counter-
parts in love and sympathy for one’s allies, generosity to war
victims at home and abroad, the introduction of ^Tlue sky

1 An address prepared for the regular semi-monthly meeting of the Denison
Scientific Association, December 17, 1918.

2 W. C. Ebaugh, Potash and a world emergency. Jour. Indus. Eng. Chern..
vol. 9, p. 688, 1917.

33

34

W. C. EBAUGH

diplomacy/’ and the abolition of secret treaties, the organization
of benevolence on an unprecedented scale, and the expenditure
of time and money to repair wastage — not for self, but for those
who would have been considered aliens, beyond the pale of one’s
normal interest a few months ago.

It has been well said that the sinews of war are men, munitions
or material, money and morale. In the second category come
explosives and the enginery of war, clothing, shelter and food.
And the greatest of these is food — food not only for men at the
front, but for all the people of the nation at war. The maxi-
mum production of food without fertilizers is impossible, and
Liebig’s doctrines that phosphates, nitrogen and potash must
be put into soils to replace these constituents removed with
crops and transported to distant places, have found ever increas-
ing acceptance since they were published some seventy-five
years ago. Of these three plant foods, the Allies and the United
States had access to phosphates and nitrogen in sufficient
amounts, but in the case of potash, Germany was sole dictator.
In fact, her control of this great natural monopoly constituted
her Affine big economic weapon” which she threatened to use
in such a way that the nations of the world would be brought
starving to her doors, begging for potash that they might have
bread!

STASFURT DEPOSITS

The story of Stasfurt salt deposits is one of great interest.
For centuries salt had been obtained from this district in north
central Germany, near Magdeburg, and the deposits are known
to be at least 100 square miles in area, with strata 3 to 4 inches
thick and with some 15,000 “rings” or layers, indicating that
the salt required at least 15,000 years for its deposition. Judg-
ing from workings down to the 3300 foot level, it has been esti-
mated that brine, from which these salts came, would have
covered the earth to a depth of 50 miles, that the temperature
during at least a part of the time evaporation was taking place,
varied from 80° to 160°F. and that “conditions for air evapora-
tion were exceedingly favorable during the Permian period.”

AMERICANS ADVANCE IN POTASH PRODUCTION

35

Borings were begun in 1837, salt was encountered in 1843, and
shafts were sunk between 1851 and 1856. Disappointment
ensued, because ''bitter salts’’ and not rock salt, were found.
But the value of these "bitter salts” as a source of potash was
soon recognized. Frank, a sugar chemist, worked out a method
6f10RT TOm
300000

200000

too 000

Fig. 1. Imports (open rectangles) and domestic production (shaded rec-
tangles) of potash (K2O) in United States 1904-1918.

for extracting potassium chloride from the mixed sodium-potas-
sium-magnesium salts, and the first factory was erected in 1861.
From that time until 1914 Germany monopolized the world
trade in potash.

The extent of Germany’s exports of potash to the United
States is shown in the accompanying diagram (fig. 1). Although

36

W. C. EBAUGH

both crude and refined salts are shipped, for purposes of com-
parison all are calculated to a ‘^potash” or content. In

1912 the exports from the German Empire and the imports
into the United States were:

EXPOETS FEOM
GEKMANY

IMPOETS INTO
U. S. A.

Crude potassium salts

met. tons

1,300,559

286,528

85,452

48,540

met. tons

650,297

190,775

35,366

14,172

Potassium chloride

Potassium sulphate

Potassium magnesium sulphate

1,721,079

890,610*

* Equivalent to 65 cars, 100,000 pounds capacity, six days a week throughout
the year.

This immense amount of potash was consumed very largely
(about seven-eighths) in the fertilizer industry, and found its
chief use in the south-eastern part of our country. Cotton,
tobacco and cereals are the chief crops requiring potash
fertilizers.

WAR AND THE BLOCKADE

With the catastrophe of war, the allied nations and the United
States faced a desperate situation. Stocks of potash on hand
were relatively small, and no other source than that in Germany
was available. Even deposits — similar to those at Stasfurt —
said to exist in Alsace-Lorraine, were in territory controlled by
the Central Empires. The law of supply and demand was illus-
trated at once — prices soared from the ordinary level (a little
under $40 per ton) to unheard of heights, but even then potash
could not be had (fig. 2).

The technical press soon echoed Germany’s boast that a
starving world would be brought begging on its knees for potash
fertilizers, and let it be known that this was the one great eco-
nomic weapon possessed by the enemy. America’s response was
immediate. A search for potash, both on the part of govern-
mental bureaus and of private parties, was begun, and the country

ameeica’s advance in potash production

37

was examined as never before for this substance. Other nations
joined in the search, but nothing comparable to Stasfurt could
be found. Under these conditions, therefore, it is not strange
that efforts were put forth to secure potash from industries
of the ^Var-baby’’ type, and to recover it as a by-product
from existing plants. The success attending these efforts is
remarkable.

Fig. 2. Monthly prices in dollars per ton for ‘Tof^ssium muriate” (80 per
cent), 1913-1918.

INORGANIC SOURCES

a. Lakes and brines. In 1912 some students from the Uni-
versity of Nebraska filed claims on certain alkaline lakes in the
western part of their state, and during 1914 development of an
alkali industry was begun. The treatment of the brine is very
simple; it is pumped into settling tanks, evaporated in vacuum
pans similar to those used in sugar factories, crystallized and

38

W. C. EBAUGH

shipped in a crude state. The commercial product must con-
tain 14 per cent of potash, but it is not difficult to maintain its
content around 25 to 35 per cent. This industry has grown
until a dozen or more plants are pumping brine from lakes over
an area of 230 square miles. The major part of potash pro-
duced in this country during the first two years of the war came
from the Nebraska lakes.

In the eastern part of California and neighboring portions of
Nevada is an immense arid area that held promise for the potash
prospector. Death Valley and Panamint, names associated in
the popular mind with desert, desolation and starvation, repre-
sent typical districts where deposits were looked for; men seemed
to feel that potash would be found as surface deposits, not real-
izing that those at Stasfurt were revealed only by deep borings.

At Searles Lake, California, is found the residue of an inland
sea. Salt is firm and solid for about 15 to 25 feet and then brine
or loose crystals form a layer 65 to 75 feet deep. Potassium
chloride occurs to the extent of 4 per cent, and the total amount
of this constituent is estimated at 24,000, OQO tons. A plant was
installed consisting of pumps, storage tanks and triple effect
evaporators capable of handling 200,000 to 250,000 gallons brine
and 100,000 gallons mother liquor per day. In September,
1918, production was at the rate of 1800 tons of crude potassium
salts per day, and it was expected to raise the production to
4500 tons of salts, containing 75 to 80 per cent potassium chlo-
ride, early in 1919. In other words, it was estimated that this
one source would be supplying about one-eighth of the pre-war
consumption of potash.

At Salduro, on the Nevada-Utah border, and at Great Salt
Lake, Utah, plants have been erected for the extraction of po-
tassium salts by processes similar to those mentioned above, and
much crude potash has been shipped to fertilizer factories and
chemical plants. One company has operated for years at Great
Salt Lake, making common salt and sluicing the mother liquors,
rich in potash and magnesia, back into the lake. Its capacity
was 100,000 tons of salt per year; the enhanced value of its prod-
ucts now that potash brings such prices, is self-evident.

AMERICANS ADVANCE IN POTASH PRODUCTION 39

During 1917 brines supplied more than 60 per cent of the
total potash production in the United States.

h. Alunite. Alunite is essentially a basic sulphate of alumi-
num and potassium containing ^ ^potash’ ^ (K2O) to the extent
of about 11 per cent in the best varieties. At Marysvale, Utah,
deposits have been developed on a large scale and a steady out-
put of potassium sulphate has been maintained. At Sulphur,
Nevada, are less well known deposits.

The treatment, of alunite consists essentially of roasting the
mineral, usually in rotary kilns of the cement-burning type, to
drive off a part of the sulphur trioxide, convert the alumina
into an insoluble form and the potash into a soluble sulphate.
The last named salt is then extracted with water, separated from
the insoluble residue, and recovered by evaporation. As no
satisfactory method for disposing of the by-product alumina has
yet been made, commercially, the industry is generally viewed as
being of the ^Var-baby type,’’ but capable of stabilization
through development of by-products when readjustment to peace
conditions occurs. During 1917 the production amounted to
2400 tons of potash, or about 8 per cent of the nation’s output.

c. Cement kilns. At Riverside, California, a cement plant
was compelled to abate its dust nuisance, and applied the Cot-
trell process of precipitation, i.e., passing flue gases between
electrically charged conductors maintained at high potential
differences. The removal of 95 per cent of the solids was at-
tained with relative ease, and to the surprise of the technical
staff it was found that a large portion of this recovered dust con-
sisted of water soluble potash, or of material that could readily
be made water soluble. It is another illustration of a fact
so often seen in industry — a plant is forced to correct a nuisance,
and the improvements installed yield valuable products that
formerly escaped, thus adding to the earning power of the plant.
Modifications of this process were installed later for cement
plants located at Hagerstown, Maryland, Salt Lake City, Utah,
and other points, and success so far attained indicates that the
adoption of this or similar systems will become general, espe-
cially in the east.

40

W. C. EBAUGH

d. Iron blast furnaces. Gases from iron blast furnaces must
be cleaned before they can be used in gas engines. The Cottrell
process mentioned above has proved its value in this service,
and the ores of certain districts, Alabama in particular, contain
such quantities of potash that recovery of this material becomes
of great economic importance. Only 200 tons of potash were
made from these sources in 1917 — all of which came from ex-
perimental plants — ^but largely increased yields are expected in
1919.

R. K. Meade has estimated that an expenditure of $37,000,000
for potash recovery plants at iron and cement plants throughout
the country would add 200,000 tons of by-product potash, or 80
per cent of our pre-war consumption, to America’s output. This
would be a low price to pay for economic independence in this
line, and the amount involved seems small indeed when com-
pared with war-time ^ ^drives” for $30,000,000 for Armenian and
Syrian Relief, $170,000,000 for a United War Work Campaign,
$200,000,000 for a Red Cross Fund or a $6,000,000,000 Fourth
Liberty Loan! And the irony of fate is again evident.
America’s chemists and engineers have shown how to wrest Ger-
many’s “one economic weapon” from her hands by recovering
and utilizing nuisance-creating material that is now allowed to
go to waste on an enormous scale, by industries well established
and easily able to provide necessary plants and technical skill.

e. Manufacture from silicates. For decades it has been recog-
nized that the logical source of potash is silicate minerals, and
much effort has been expended on developing processes to ex-
tract potash from feldspar, leucite (Wyomingite), glauconite or
green sands, and similar material. Recently it has become
general knowledge that tailings dumps often represent large
quantities of locked-up potash; those at Cripple Qreek, Colorado,
run 10 per cent in potash, and those from the Utah Copper Com-
pany’s mills, at Garfield, Utah, carry more than 6 per cent of
this constituent. Such tailings are already finely ground and
constitute the most accessible source of raw material for a sili-
cate potash industry. The Utah Copper mills alone, treating
30,000 tons of ore daily, could supply enough raw material

America’s advance in potash production 41

(tailings) to yield 360,000 tons of potash annually, granting that
only a 75 per cent extraction was made. This would be about
150 per cent of the pre-war consumption. And worthy of care-
ful consideration is the fact that cement, also, could be obtained
as a product from such a plant. The difficulties in the way are
those of transportation and markets, rather than those of ma-
terials and processes; they are economic rather than technical.

Of the large number of methods proposed for treating sili-
cates in order to obtain potash, heating with lime or magnesia
and a. chloride or sulphate of the alkali or alkali-earth metals,
seems to be most highly esteemed. Mill tests have been so
favorable that the adaptation of existing cement plants (as at
Devil’s Slide, Utah) and the erection of new plants (as at Green
River, Wyoming) for the treatment of leucite, are now under
way. Feldspar yields its potash less readily than does leucite,
but even at that good extractions are to be had, and it is prob-
able that only the fear of ruinous competition on the part of the
German Kalisyndikat has prevented capital from entering this
field more extensively.

Entirely unlike the processes outlined above are those pro-
posed for utilizing glauconite or green sand. This material can
be decomposed by water, or by water and carbon dioxide, under
pressure at high temperatures, and quite pure potassium hydrox-
ide or carbonate made in one operation. The by-product formed
can be used for manufacturing building materials resembling sand-
lime brick. Unfortunately deposits of glauconite in a sufficiently
pure state are far less extensive than those of the other potash-
bearing minerals.

ORGANIC SOURCES

d. Suint from wool washing gives potassium carbonate on
ignition. About 300 tons of potash (K2O) came from this source
in 1917.

b. Beet sugar residues^ especially those from the Steffens proc-
ess, gave 360 tons potash in 1917.

c. Molasses from cane sugar factories, and distillery waste gave
2850 tons of potash in 1917.

42

W. C. EBAUGH

All three of these sources are capable of great expansion, but
cannot be viewed as main sources of potash. The last two men-
tioned contain nitrogen as well as potash, and are therefore
doubly valuable as fertilizers.

d. Wood ashes. Until 1860 wood ashes constituted the most
important source of potash, the supply coming chiefly from
Canada and Russia. The introduction of Stasfurt salts in 1861
killed the industry. Normally not even the dust from inciner-
ators at lumbering camps can be worked up profitably. During
1917, however, 425 tons of potash from this source were pre-
pared in this country.

e. Kelp. The collection of kelp (seaweed) on the coasts of
Scotland and France has been carried out for more than a century.
The crop was then burned and used as a fertilizer. Like the
wood ash industry it was snuffed out by Stasfurt potash in 1861,
except in so far as it afforded a source of iodine.

During late years both governmental funds and private capital
have been spent lavishly in investigating the possibilities of the
Giant Kelps along the Pacific coast. These fields extend from
Lower California to Alaska, and it was hoped that they would
afford limitless supplies of potash. Most of the reduction plants
have been erected in the neighborhood of San Diego, California.
Two general processes have been tried, incineration and fermen-
tation. In 1917 the production of potash from kelp amounted
to 3575 tons, and in 1918 it did not exceed 9000 tons. The kelp
is cut by seagoing dredges, acting like huge mowing machines,
transported to land and dumped. It is said that it costs $1.10
to harvest and dump a ton of seaweed averaging only 1.5 per cent
potash, or $85 per ton of potash brought to land. Under these
conditions not much hope can be entertained for the permanent
success of an industry that aims to yield potash as a main
product by the incineration method.

But much more favorable is the outlook for plants like that
of the Hercules Powder Company. That company needed ace-
tone and other organic solvents, and worked out processes for
getting them from the fermentation of seaweed. The outlay
for apparatus was enormous, and the scale of operations is

America’s advance in potash production

43

immense, but as acetone, oils, esters, organic acids, algin, iodine,
salt and potassium compounds are prepared in correspondingly
large amounts, there is reason to view this as a permanent in-
dustry, and not one to cease with the coming of peace. With
large technical staffs and expert sales organizations available,
the outlook is favorable.

CONCLUSION

And thus we see how Germany’s ^Vaunting ambition doth
o’er leap itself” as truly in technical fields as in military and
governmental affairs. She had the world buying potash from
her mines, and a fleet of merchantmen carrying it to the utter-
most parts of the earth. Her customers paid whatever price
was demanded, and considered competition hopeless. Then
came war, and long preparation for a short, intense campaign —
like those waged under Bismarck’s direction — gave her an in-
stant advantage over peaceable nations who thought of war in
terms of Sherman’s definition. Conquest for booty, loot and
subjugation of alien peoples — sordid and selfish motives all —
was to the Junker and militarist only “big business.”

But how she miscalculated the moral, mental and material
reserves of an outraged world! Instead of having but one or
two antagonists to dispose of at a time, the other nations being
cowed into inaction through physical fear, she was soon sur-
rounded by the dreaded wall of blood and iron, a circle of steel,
and brought to bay, with a world against her. The eleventh
hour of the fateful eleventh day of the eleventh month, 1918,
marked the end of actual hostilities. What a reversal of form!

And what a shock it will be to the government-controlled
Kalisyndikat to realize that its monopoly has been broken, that
America increased its potash production from practically noth-
ing in 1914 to 10,000 tons in 1916, 33,000 tons in 1917, and
65,000 tons in 1918, with the prospect of ever increasing produc-
tion until all that is needed can come directly from local plants !

America’s economic independence of German potash is thus
a valuable by-product of this frightful World War, a result en-
tirely unforeseen by friend and foe in 1914. The end has not

44

W. C. EBAUGH

been reached without hard work, scientific skill, ample capital,
constructive ability and business daring on the part of our citi-
zens, but this victory in an art of peace is no less splendid than
that won in war itself. Its story constitutes another chapter
in the romance of American industrial achievement.

ADDENDUM

Revised statistics issued since the above was written give a
somewhat . smaller production of potash during 1918 than was
estimated in October of that year. Press Bulletin No. 399 (Feb-
ruary, 1919) of the United States Geological Survey reads in
part as follows:

Statistics of the production of potash in the United States in 1918,
which are complete except for reports from some of the smaller pro-
ducers, show a large increase of output. The returns now at hand
indicate a total production of 192,587 short tons of potash materials
containing 52,135 short tons of actual potash (K2O). They are sum-
marized in the following tables, compiled by W. B. Hicks, of the United
States Geological Survey, Department of the Interior.

Potash produced in the United States in 1918, classified according to sources

SOURCES

NUMBER OF
PRODUCERS

TOTAL

PRODUCTION

AVAILABLE
POTASH (K2O)

Natural brines

21

tons

147,125

tons

39,255

Alunite

4

6,073

2,619

Dust from cement mills

9

11,739

1,429

Kelp

6

14,456

4,292

Molasses distillery waste

4

9,505

3,322

Steffens waste water

5

2,818

761

Wood ashes

26

609

365

Other sources

3

262

92

Total

78

192,587

52,135

The production in 1918 was almost double that in 1917. About 75
per cent of the total output came from natural brines, 55 per cent com-
ing from brines in Nebraska alone. Most of the product was in the
form of mixed salts and fertilizer materials containing from 20 to 30

AMERICANS ADVANCE IN POTASH PRODUCTION 45

per cent of potash (K2O). About 24 per cent of it was in the form of
muriate and about 6 per cent in the form of sulphate.

For several years immediately before the European war the United
States used annually an average of about 240,000 short tons of actual
potash (K2O). The production so far reported in 1918 is therefore
about 22 per cent of our normal consumption. The imports during
1918 were very small. The producers reported that on January 1,
1919, they had in storage 60,426 tons of crude potash, held because of
the dull market prevailing during the latter part of 1918. These figures
represent a minimum, as some producers did not give quantities, but
stated that they had produced considerably in excess of sales. Most
of the potash now held in storage was produced when the price was high,
when quantity production was the main object, and when competition
with foreign potash was not considered. The price now offered for that
material is apparently below the actual cost at which many firms pro-
duced it, consequently there is a crisis in the domestic potash industry.
Many producing plants have already shut down, and others are marking
time.

The producing capacity of American potash plants, classified ac-
cording to sources of raw materials, is estimated roughly as follows:

Capacity of American potash plants

• SOURCE

AVAILABLE
POTASH (K2O)

Natural brines

Nebraska lakes

tons

50.000

28.000

4,000

3.500

5.500

4.000

3.000

1.000

1,000

Other sources.

Alunite

Dust from cement mills

Kelp

Molasses distillery waste

Steffens waste water

Wood ashes.

Other sources .'

Total

100,000

This quantity corresponds to more than 40 per cent of our normal
consumption and indicates what may be produced in the United States
during 1919 provided the American producers are able to compete with
foreign producers.

46

W. C. EBAUGIl

It is evident that plants extracting potash from kelp were
among the first to shut down after the signing of the armistice,
and that many contemplated enterprises were allowed to die.
Offsetting these abandoned projects in part at least, it should
be noted that plants for making potassium chloride and sulphate
from leucite are now operating.

THE USE OF OUTLINE CHARTS IN TEACHING
VERTEBRATE PALEONTOLOGY

MAURICE G. MEHL

It is undoubtedly the common experience of all teachers of
vertebrate paleontology and comparative osteology that only
those anatomical structures or relations presented to the student
through visual instruction become a part of his real working
store of knowledge. Occasionally the exceptional teacher is
able to fix uninteresting facts in the student’s mind by means
of fitting illustrations, fascinating stories, or accounts of first
hand experiences. Certain it is, however, that only in pro-
portion as the student visualizes a structure is he able to retain
it. For this reason the teacher of paleontology usually feels
very keenly the need of a large supply of museum or laboratory
materials; mounted skeletons, skeletal parts, drawings, charts,
transparencies, etc.

There are few colleges or universities that have an adequate
supply of skeletal material for teaching vertebrate paleontology
to the best advantage. Even so, much of the material avail-
able is not entirely safe in the hands of the inexperienced student.
As a rule the lack of space, the cost involved, or the fact that
collections are built up but slowly and many specimens cannot
be duplicated, holds the collections down to a few illustrative
types. Each institution is inclined to specialize in, to over em-
phasize, perhaps, the group or groups which are most available
to it, and for illustrative material in other groups the student
is forced to depend on written or oral descriptions and drawings.
Were one able to study in several institutions till the entire field
had been covered this would constitute ideal instruction, to be
sure, but this is impossible in many cases.

It was because of a lack of skeletal parts by means of which
the student could become thoroughly acquainted with the struc-

47

Copyright, 1919, by M. G. Mehl.

48

MAURICE G. MEHL

tures illustrating the main types of vertebrates that the writer
was led in an attempt to supply the materials by means of charts.
It was recognized that even when certain structures were well
described, such illustrations as were available were often in-
adequate and gave the student little more than an idea of the
shape of the bones. Even to gain this it was usually necessary
to work through a great mass of literature, often not available.
To work out a chart for each form or group with which it was
desired to become familiar would mean an endless task. Fur-
thermore, such charts would not have the vital interest which
the preparator gains as he ^Vorks out’^ and mounts a skeleton.
It was thought that could the student be furnished with a set
of conventional ^^paper bones’^ from which he could construct
skeletons at will, much of the difficulty of teaching the verte-
brate skeleton would be eliminated.

Some time ago the writer conceived the idea of compiling a
guide chart on which were designated the elements in the primi-
tive skull together with the conspicuous openings in their proper
relations. Working oh the principle that organic evolution in-
volves only the loss of parts or the modification of existing ele-
ments, the student was expected to construct any skull from the
base by discarding or utilizing the lines bounding the primitive
elements.

The results of this experiment were very gratifying. While
the guide chart had been compiled for the sole purpose of supply-
ing laboratory materials, it was found that it answered other
purposes as well. In the first place the student came to realize
that it was the elements and openings and their relations in the
skull that were all important ; the size and shape were of second-
ary consideration. The use of the same size and shape of
skull to show the structure of various types seemed to give a new
meaning to the word ^ ^structure” : the student observed that
between the largest and the smallest dinosaur skulls there were
fewer differences than between many skulls that in a hasty
glance seemed very similar.

Again, he came to a realization, as never before, that every
form, no matter how complicated, was merely a modification,

USE OF CHARTS IN TEACHING VERTEBRATE PALEONTOLOGY 49

through loss chiefly, of a pre-existing, more generalized type,
a fact strikingly presented by the discarded parts that accompany
every ^^finished^^ skull.

Not least of the advantages of the guide charts was the manner
in which they assisted the student to become familiar with the
technical terms. After he has worked out several types and
labeled each element, every name comes to have a rather definite
meaning.

Encouraged with the results gained from the use of the chart
I for the skull and at the suggestion of the late Dr. S. W. Willis-
ton, the writer attempted the compilation of guide charts for
the limbs and the vertebrae. These guide charts, together with
some suggestions as to their use are presented herewith.

THE SKULL

The chart for the skull, plate IX, consists of dorsal, ventral,
and posterior views. It is accompanied by a form suitable for
student use in the laboratory. While the chart was designed
primarily to illustrate the amphibians and reptiles, it may be
used for the mammals and birds. The solid lines mark the out-
lines of the skull and, the openings commonly present such as
the orbits and nares. It is only in exceptional cases, for in-
stance, to close the otic notch, that these lines should be modified.

In the dorsal view the elements found in the primitive skull
are outlined by dots. Each bone in the type to be represented
should be designated by following its dotted outlines with heavy,
preferably red, lines. When an element or elements are missing,
the outlines are ignored and the adjacent bones are expanded
in the proper directions to fill the space and maintain the proper
relations. In the exclusion of the lacrimal from the nares
and in other rare instances, the dotted lines will necessarily be
changed slightly.

In the ventral view the same plan is followed as in the dorsal.
The dotted lines give a choice between a single and a double
occipital condyle. A large and small interpterygoid vacuity
are designated by dashed outlines and a dotted line from the

50

MAURICE G. MEHL

anterior end of each gives a choice between a large and small
parasphenoid. It will be found that with the use of the small
vacuity and small parasphenoid, the sutures between the pala-
tines, pterygoids, and vomers will have to be slightly modified.

A false palate may be indicated by adding a line drawn across
the bones of the palate along points at which the fold takes
place. Arrows pointing from this line to the median line of the
skull indicate the fold somewhat more effectively.

Teeth on the various elements may be designated by circles
or crosses. The various types, thecodont, acrodont, etc., may
be designated by special symbols agreed upon.

The posterior view gives a choice between a single and double
occipital condyle. When the single condyle is utilized the out-
line remains unchanged. The suture between the tabular and
the. paroccipital is left incomplete so that it may be continued
toward the median line of the skull in any direction so as to
maintain the desired relations between the supraoccipital and
the laterally adjacent bones.

An index sheet, plate VIII, furnishes the names in common use
for the various bones of the skull. Most of the openings are
indicated in a like manner. To eliminate confusion, openings
are indicated by a curved line beneath the abbreviation for the
name. Unpaired bones are underscored with a straight line.
In filling out a chart the same abbreviations should be used as
are given in the index sheet, and the openings and unpaired bones
should be designated in the same manner.

THE LIMBS

The guide chart for the limbs, plate X, furnishes outlines for
both the front and the hind legs. Names of the various elements
should be added by the student. All of the elements in the
primitive leg are represented by conventional designs save in
the case of the mesopodials. Here there is so much doubt as to
the primitive arrangement and number, and such a variation
among known forms, that only the lines to designate the three
rows are given. Between these, vertical lines may be drawn to

USE OF CHARTS IN TEACHING VERTEBRATE PALEONTOLOGY 51

indicate the number and relative proportions of the bones in
each row. The loss of all or a part of the ulna or fibula may be
shown by ignoring the outlines of these bones or by using only

Hind Leg.

Fig. 1

those lines bounding the part retained. The fusion of two
bones is indicated by omitting the division between them. In
the humerus the presence of the ectepicondylar or entepicondylar

52

MAURICE G. MEHL

foramen is indicated by following the dotted circles near the
distal end of this bone. These foramina may be further em-
phasized by placing a cross within the circle. A hyperphalan-
geate or hyperdactylate condition in the hand or foot may be
indicated either by the addition of new squares or the splitting
of the present rectangles by vertical or horizontal lines or both.

The accompanying diagram, figure 1, shows how the com-
pleted chart for a purely hypothetical form might appear. The
features indicated are the loss of the shaft portion of the fibula
and the fusion of the upper and lower ends of this bone with the
tibia; the loss of the first, second, and fifth metatarsals and the
partial fusion of the third and fourth; and the loss of all the
phalanges in the first, second, and fifth fingers and the loss of
one and two phalanges in the third and fourth fingers respec-
tively. In the tarsus there are but two rows of bones with three
elements in the proximal and two in the distal row.

THE VERTEBRAE

While the guide chart for the composition and modification
of the vertebrae, plate XI, is not all that could be desired for
certain primitive forms, it works well for the great majority of
types. The names of the parts should be added by the student.

In the end view given in this chart a perforate or solid centrum
may be shown. The upper set of dotted angles near the neural
canal is used to show the presence of the zygosphene and the
lower set is for the hyposphene. While the lateral view shows
the presence or absence of the hypocentrum and its relative size,
it is also shown in the end view where it may be designated as a
single unit or composed of two parts.

In the lateral view the composition and modification of the
centrum may be more fully shown. Temnospondylous types
as illustrated by Cricotus and Eryops may be shown by util-
izing certain of the dotted lines while holospondylous forms are
indicated by ignoring these. The presence of an intercentrum
is indicated by following another dotted line that cuts off a
small triangular space in the lower anterior corner of the out-

USE OF CHARTS IN TEACHING VERTEBRATE PALEONTOLOGY 53

line of the centrum. For amphiplatyan vertebrae the lines at
the ends of the centrum are not altered, but for procoelous,
opisthocoelous, and amphicoelous types the suitable curved
dotted lines are to be used. It has been found useful to out-
line the several elements composing the vertebrae with hachures
as is shown in the illustration of foot structure (fig. 1).

The importance of the rib articulation has long been recog-
nized. No two animals with different rib articulations can be
closely related. For this reason the facets on the vertebrae
should be carefully noted. In the lateral view of the vertebra
the small dotted circles permit the designation of all possible
rib attachments. For a double, diapophysial attachment a
cross should be placed in each of the two circles on the diapo-
physis. Obviously the small half circles at the posterior end of
the centrum are used to indicate intervertebral attachments.

No doubt the guide charts as here presented are inadequate
in many respects and not unlikely will they be found to contain
certain errors. Other uses of the charts may suggest themselves
and perhaps other forms may be added. The writer has tried
forms for showing the structure of the pectoral and pelvic girdles
and also a form for showing the evolution of the teeth. In both
of these cases, however, the results were of doubtful benefit
because of the complexity of fche charts.

PLATE VIII

Av, antorbital vacuity

Pal, palatine

Bo, basioccipital

Pao, paroccipital (opisthotic

Bs, basisphenoid

Par, parasphenoid

En, external nares

Pf, parietal foramen

Eo, exoccipital

Pm, premaxilla

Et, ectopterygoid (transverse)

Po postfrontal

Ds, dermosupraoccipital (postparietal)

Poo, postorbital

Fm, foramen magnum

Ppf, postpalatine foramen

Fr, frontal

Prf, prefrontal

In, internal nares

Pt, pterygoid

Ipv, interpterygoid vacuity

Qj, quadratojugal

It, intertemporal

Qu, quadrate

Itv, intertemporal vacuity

So, supraoccipital

Ju, jugal

Sq, squamosal

La, lacrimal

St, supratemporal

Ltv, lateral temporal fenestra

Stv, supratemporal vacuity

M, maxilla

Ta, tabular

Na, nasal

Vo, vomer

Or, orbit

an opening

P, parietal

' — an unpaired bone

THE SKULL
{Copyright, 1919, by M. G Mehl.)

Bulletin Scientific Laboratories Denison University Vol. XIX

M. G. MEHL: OUTLINE CHARTS VERTEBRATE PALEONTOU

Subject

N ame

References

I

Q ;

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE IX

Subject Type

Name Date Exercise No,

References

{Copyright, 1919, by M. G. Mehl.)

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE X

Hind Leg.

Front Leg.

I L_ J

L . 4- - 4- • 4- . 4 . -I

l.4.

I-- -I- -J

L..4. 4--:

M. G. MEHL: OUTLINE CHARTS VERTEBRATE PALEONTOLOGY.

r "I

r * T - T
> I I

r-i'T

L .1 .4.
I

4-. I
I I I

T - t -T ■
I I I
"-T’l
L. J

THE LIMBS
{Copyright, 1919, hy M. G. Mehl.)

Bulletin Scientific Laboratories Denison University Voi. XiX

PLATE XI

M. G. MEHL: OUTLINE CHARTS VERTEBRATE PALEONTOLOGY.

THE VERTEBRAE

(Copyright, 1919, by M. G, Meki.)

/

SOME FACTORS IN THE GEOGRAPHIC DISTRIBUTION

OF PETROLEUM

MAURICE G. MEHL

Few industries have experienced such rapid or so compre-
hensive development as has the petroleum industry. The use
of petroleum and its products is so firmly fixed in the affairs of
man and so important are these products to his activities of in-
dustry and pleasure that even a slight reduction in the petroleum
output would probably work real hardships on a large proportion
of the human race. The discovery of new areas of accumulation
of petroleum and the rapid development of these new fields have
followed each other in rapid succession during the past few years.
Production, nevertheless, scarcely keeps pace with the growing
demands.

Some look with alarm on the rate of consumption of our
known supply of petroleum and many are already studying the
possibilities of new stores from other sources or other regions.
Not a few of the larger corporations are sending representatives
from time to time to investigate the possibilities ip. unexplored
or inadequately tested parts of the world.

Whether an actual shortage faces us at some near date or not,
certain it is that at some future time it will be necessary, or at
least desirable, to determine what may be expected in the way
of a world supply of petroleum. When prospecting is carried
into regions of unknown possibilities, to countries not now im-
portant as producers of petroleum, what is to be the guide; what
shall determine the order in which the various “possible’^ regions
are to be investigated? Just as today experts are able to desig-
nate the most favorable places for testing a given region, will it
not be possible in the future to indicate, within the confines of
well founded theory, at least, a logical order in which the land
masses of the earth should be tested?

55

Copyright, 1919, by M. G. Mehl.

56

MAURICE G. MEHL

In the following paragraphs the writer attempts to correlate
certain facts and observations which may assist in the solution
of some of the problems in the geographic distribution of petro-
leum. There is no attempt at exhaustive treatment and little
or no claim is made for originality. It is hoped that the specu-
lations will call forth a discussion of the principles involved and
possibly stimulate investigations in the several branches of
science interested. It is only through the cooperation of the
experts in these sciences that adequately supported conclusions
as to the likely distribution of petroleum can be reached.

Considering petroleum and the related substances as a group,
they are among the most widely distributed minerals; there are
but few unmetamorphosed sedimentary beds that contain no
trace of these hydrocarbons. Small showings are found en-
circling the globe and they extend from well toward the poles
to the equator. Workable accumulations are much less widely
distributed, however, and great commercial deposits are com-
paratively rare.

On the accompanying map, plate XII, are platted the more
important areas of production throughout the world. It will
be noted at once that these major accumulations, as they may
be termed, are confined to the northern hemisphere. It will
also be seen that none of the areas indicated extend north of 50°
N. latitude nor south of 20° N. latitude. In fact, if one is to
avoid extremely sinuous lines, perhaps no better boundary could
be desired than these parallels.

True, outside of this belt are known deposits of some magni-
tude, accumulations that might be classed with the major fields,
such, for example, as those of Alaska, Peru, or Ecuador. These
and other possible exceptions, however, are in no wise comparable
with the productive areas about the Black and Caspian Seas,
the Lorraine district, the great belt across the United States, or
the accumulations in Mexico.

Attention is further called to the general correspondence be-
tween the position of the twentieth and fiftieth parallels in both
hemispheres with the average annual isotherms of 70° and 40°
respectively. Although these parallels are, in reality, nothing

GEOGEAPHIC DISTRIBUTION OF PETROLEUM

57

more than imaginary lines of geographic reference, each does,
in much probability, mark the average position of some isotherm
as it has shifted in past geological times. While the disposition
of maximum accumulations as here bounded does not indicate
a definite temperature zone within which petroleum has been
formed, it does suggest a distinctly zonal distribution of petro-
leum in which temperature may have been an important factor.

At once the question arises as to whether these apparent
boundaries of the zone of maximum accumulations fit well with
the actual conditions or whether further investigation will greatly
modify the shape and extent of the ^ important’’ areas. If there
is this actual zonal distribution of petroleum, one must consider
several factors involved in such limitation and with these specu-
lations others follow such as the possibility of a ‘ ^barren’ ^ equato-
rial belt and a productive zone in the southern hemisphere cor-
responding with that of the northern.

There is, of course, grave danger in assuming that the belt of
maximum production is as observed, or that such an area may
be expected to have anything in the way of a definite boundary,
even theoretically. There can be little doubt, for instance, that
this zone has offered. the most favorable conditions for explo-
ration and it is not unlikely that with more extensive prospecting
other great accumulations of petroleum will be found, possibly
well outside these approximate boundaries.

Regardless of the lack of thorough prospecting, however, there
is reason to believe that of the three zones, the equatorial
belt between the twentieth parallels and adjacent belts in the
northern and southern hemispheres extendingn orth and south to
the fiftieth parallels, the northern belt will, when investigations
are carried to completion, be found the more productive. For
instance, one may safely assert that, all other factors being equal,
the amount of petroleum underlying a given area is directly pro-
portional to the size of that area. It is evident that in the area
of exposed lands neither the southern nor the equatorial belts
compare favorably with the northern zone.

Inasmuch as important accumulations of petroleum in Pre-
Cambrian rocks are unknown, certain broad areas of Pre-Cam-

58

MAURICE G. MEHL

brian and igneous rocks may at once be designated as impossible
territory. The proportion of the possible productive territory
to the total area in each zone differs greatly. Again the differ-
ences favor the northern zone for the proportion of the Post-
Cambrian area to the total land surface is much greater in this
belt (see plate XIII). Furthermore, the ^^possible’^ territory in
the other zones includes considerable areas that may properly
be eliminated because of the presence of sediments representing
periods that are generally barren throughout the world, such as
the broad expanse of supposed Triassic rocks in northeastern
South America and the great areas of Mesozoics in eastern Aus-
tralia and central Africa.

The foregoing considerations are all, in a sense, passive agents,
factors which would tend to minimize the importance of petro-
leum accumulations outside of the northern belt. So closely
confined to this belt are the great accumulations as they are
known today that it is thought there must be a more active
determining factor; one of the fundamental influences in the
formation of petroleum. Of these, one of the most far reaching
is probably the temperature consideration.

It may safely be granted, perhaps, that petroleum is derived
from organic matter. Without going into the evidence it may
also be stated that there is reason for assuming that no par-
ticular group or groups of organisms may be designated as the
source of petroleum except that all evidence points to the fact
that it is only the smaller plants and animals, perhaps largely
the microscopic forms, and fragmental material from larger
organisms that are available.

It is evident that there is a marked dependence of life on
temperature conditions. Perhaps this one factor, more than
any other, determines the variety and abundance of life through-
out the world. It is recognized that the amount of agitation of
the waters, the degree of salinity, the nature and amount of
sediment, the depth of the water, etc., are very important factors
in the distribution of marine life, but for every temperature
these other conditions may be found in almost endless variety
and combination. Still, life is not equally abundant in every

GEOGRAPHIC DISTRIBUTION OF PETROLEUM

59

temperature, \\niile it is true that there is more or less of a
‘ ^patchwork’ ^ arrangement of temperatures in the ocean, cold
waters often immediately adjacent to warm waters, it may be
said in general that the temperature increases toward the equator.
Likewise, with conspicuous exceptions, the abundance and
variety of life increases rapidly toward the equator. So far as
the abundance of life alone is concerned, it seems likely that there
has been some limit, poleward from which the formation of petro-
leum has been of little importance.

Other factors concerned in the origin of petroleum from organ-
isms have been suggested, factors of equal or greater importance
than the relative amount of organic matter available. Two of
the most conspicuous of these is the rate of decay of organic
matter and the rate of sedimentation. A brief consideration of
some of the principles involved will make the importance of
these factors more evident.

Many sorts of organisms have been subjected to destructive
distillation in an attempt to produce petroleum. Of these sub-
stances a large number, both plant and animal and various combi-
nations, have produced oils very similar to natural petroleum.
It has been noted in all cases, however, that it is the fatty portion
of the organism that produces the desired results. In every case
w^here the entire organism is utilized the simulation of petroleum
is much less marked, especially in the presence of large pro-
portions of nitrogenous bases in the synthetic product. Ap-
parently in nature there has been a very efficient denitrifying
agent cooperating in the formation of petroleum.

As such a denitrifying agent, nothing more adequate, more
logical is suggested than denitrifying bacteria. While the abun-
dance, the importance, and the exact role of these organisms is
not generally understood, the principles involved are evident.
Apparently their first activity in the destruction of organic
matter is the consumption of the nitrogenous portions; the fatty
parts are for a time untouched. In the decay of a given amount
of organic detritus, up to a certain time, there is an actual
increase in the proportion of fatty material to the whole.

60

MAURICE G. MEHL

The destruction of organic matter by denitrifying bacteria is
not confined to the nitrogenous portions alone, however; in time
the fats are also attacked and, in the normal process of decay,
these too are entirely destroyed. Obviously, other factors being
equal, in those regions in which denitrifying bacteria are most
active the destruction of the fatty portions of organisms should
be fastest and most complete; there should be the least likeli-
hood of the formation of petroleum. For ideal conditions in the
formation of petroleum the denitrifying bacteria should be suf-
ficiently active to denitrify the organic base, but their abundance
should not make possible the excessive destruction of the fatty
portions.

Vaughan has pointed out the part played by denitrifying bac-
teria in the precipitation of calcium carbonate from sea water
and has stated that this activity, if not confined to tropical
waters, is at least most marked in the warmer portions of the
sea.^ Drew, in speaking of Bacterium calcis and other deni-
trifying bacteria, says:^

Such action would be almost limited to comparatively shallow
seas whose temperature approximated to that of tropical seas at the
present time.

Now, while such investigations offer no conclusive evidence
as to whether denitrifying bacteria are sufficiently active to
effectively destroy the fatty portions of decaying organic matter
in the equatorial belt, they do indicate that the destruction would
be progressively greater toward the equator, other factors being
equal. From this standpoint it does not seem unlikely that
throughout past times there have been fluctuating boundaries
beyond which, toward the equator, conditions for the formation
of petroleum have been subnormal.

^ Vaughan, T. W., Preliminary remarks on the Bahamas, with special reference
to the origin of the Bahaman and Floridian oolite : Carnegie Inst. Washington,
Pub. no. 182, pp. 47-54, 1914.

2 Drew, G. H., On the precipitation of calcium carbonate in the sea by marine
bacteria, and on the action of denitrifying bacteria in tropical and temperate
seas: Carnegie Inst. Washington, Pub. no. 182, pp. 7-45, 1914.

GEOGRAPHIC DISTRIBUTION OF PETROLEUM

61

While the importance of the temperature check on the activi-
ties of denitrifying bacteria has been indicated, it is obvious that
there must be a check of another sort as well. In any region
where the bacteria are sufficiently active to denitrify the organic
base of petroleum more or less completely, the fats would also be
destroyed were such a check, not operative.

It has been assumed by some writers that the formation of
petroleum would in itself constitute an automatic check on bac-
terial destruction by virtue of antiseptic products. This is not
in keeping with the observed processes of decay, however, and
it assumes, furthermore, that petroleum is formed almost, if not
quite, as rapidly as the nitrogenous bases are destroyed. As a
matter of fact, all evidence points to an opposite condition, the
extreme slowness with which petroleum is formed. It is,
perhaps, not far from correct to assume that the hydrocarbon
substance in oil shales is the somewhat altered organic base
which, after the lapse of an extremely great length of time, has
not yet been transformed into the ultimate product, petroleum.
It is only by hastening the process through destructive distil-
lation that petroleum may be derived from these shales.

There is, apparently, a check of a mechanical nature found in
the accumulation of inorganic sediments. It is generally recog-
nized that accumulations of soil and fine sediment materially
limit the activities of bacteria. It follows that the more rapid
the deposition of fine sediments, the more complete the check.
In much probability the fineness of the sediments has been one
of the most important of the factors determining the rock asso-
ciations of petroleum. At any rate, petroleum is associated
primarily with shales. The presence of nitrogen in varying pro-
portions in petroleum would seem to testify to the effectiveness
of the shales as a check on the destruction of organic matter on
occasion. In the cases of marked proportions of nitrogen we
may suppose, perhaps, that not only have the fatty portions of
the original base been protected, but that not even all of the
nitrogenous parts have been destroyed by bacterial activities.

It may be assumed that in general the rate of sedimentation
is slower in the equatorial belt than elsewhere, a fact evidenced

62

MAUKICE G. MEHL

by the thick accumulations of soil on these lands. Again, from
the standpoint of the inadequacy of the check on the destruction
of the fatty base by bacteria, the equatorial belt should be less
favored in accumulations of petroleum. This too is largely a
function of temperature, for the slow rate of sedimentation is in
no small measure due to the luxuriant growth of vegetation
which prevents the free wash of the rock waste from the
land.

Aside from its function as a check to the activities of denitri-
fying bacteria, the rate of accumulation of inorganic sediments
is of further importance in the formation of petroleum. Very
often the rapid decay of organisms is pointed to as illustrating
the manner in which petroleum is formed. In certain parts of
the Mediterranean Sea, for instance, the accumulation and decay
of organic detritus is so rapid that the lower levels of the water
are filled with scattered globules of oil. Instead of illustrating
how petroleum is formed, however, it points to the effective
manner in which fatty matter is ordinarily separated out from
accumulating sediments. Certainly, the globules of oil which
are escaping into the water offer no suggestion of being retrapped
and converted into petroleum. It is only that part of the organic
matter which is converted into oil so slowly that the accumu-
lating sediments form a sufficient thickness and suitable suc-
cession to retain it against the tendency of the associated waters
to drive it off, that may become petroleum.

If we may grant, then, that within a limited zone, the equato-
rial belt, conditions have been unfavorable for the formation of
accumulations of petroleum, on the average, it is logical to seek
a belt in the southern hemisphere suitable for such deposits, to
correspond with the belt in the northern hemisphere. Were
the temperature factors alone to be considered, there is little
doubt but that much might be expected from the southern zone.
It has already been pointed out, however, that the area of ex-
posed land within this zone is relatively small and of this a very
large proportion consists of Pre-Cambrian or igneous rocks. Ap-
parently little more is to be expected from the southern belt
than from the equatorial zone.

GEOGRAPHIC DISTRIBUTION OF PETROLEUM

63

Now, while in the foregoing paragraphs certain considerations
have been presented which point to the maximum petroleum
accumulations in a zone between the twentieth and fiftieth paral-
lels in the northern hemisphere, it would be a grave error to
assume that nothing is to be gained by prospecting outside of
this belt. Even if later investigations should show the specu-
lations here presented to be well founded, it would seem in keep-
ing with the theories advanced that there should occasionally
be found within the very heart of the equatorial belt, accumu-
lations of importance. As a working hypothesis only, it is sug-
gested that the prospector^ s efforts will much more likely be
rewarded in the northern than in the southern belt and that he
is least likely to achieve the desired results in the equatorial zone.

PLATE XII

The geographic distribution of petroleum. The known accumulations of
Ijetroleum of major importance are indicated by oblique lines. The size of
many of the areas is greatly exaggerated and the locations are only approxi-
mate.

Bulletin Scientific Laboratories Denison University Vol. XlX

PLATE XII

PLATE XIII

The distribution of Pre-Cambrian and igneous rocks within the equatorial
and adjacent belts. The black portions represent the chief areas of Pre-Cam-
brian sedimentaries or igneous rocks of any age. Areas concerning which no
information is available are not differentiated from Post-Proterozoic sedimen-
taries.

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE XIII

M.G. MEHL; GEOGRAPHIC DISTRIBUTION OF PETROLEUM

if 6 7 . 7 7

,0'ZO^t 1

Scientific Laboratories

DENISON UNIVERSITY

^//onal

Articles 5-8

Volume XIX

5. Notes on Isotelus, Acrolichas, Calymene, and Encrinurus. By.

Aug. F. Foerste 65

6. Some Suggested Experiments for the Graphic Recording of

Speech Vibrations. By Robert James Kellogg 83

7. The Manipulation of the Telescopic Alidade in Geologic

Mapping. By Kirtley F. Mather 97

8. The Importance of Drainage Area in Estimating the Possibilities

of Petroleum Production from an Anticlinal Structure. By
Kirtley F. Mather and Maurice G. Mehl 143

I'

GRANVILLE, OHIO, SEPTEMBER. 1919

Denison University Bulletins University Series Vol. XIX, No. 7

The University Bulletins are issued bi-monthly, and are entered at the Postoffice
at Granville as mail matter of the second class.

BULLETIN

OF THE

SCIENTIFIC LABORATORIES

OF

DENISON UNIVERSITY

Edited by

KIRTLEY F. MATHER

Permanent Secretary, Denison Scientific Association,
Granville, Ohio

The entire file of volumes 1 to 13 was destroyed by fire; no publications issued prior to
1907 are now available. Volumes 14 to date may be obtained from the editor at $2.00 per
volume, with the exception of volume 15, the price of which is $1.00. Separate parts, as listed
below, may be purchased at the prices indicated.

VOLUME 14

Articles 1-5, pp. 1-60; Nov., 1908 $0.50

Pre-Wisconsin drift in the Finger Lake Region of New York; F. Carney. 16 pp., 4 figs.

An esker group south of Dayton, Ohio; Earl R. Scheffel. 15 pp., 6 figs.

Wave-cut terraces in Keuka Valley, older than the recession stage of Wisconsin ice; F. Carney. 12 pp., 3 figs.

A form of outwash drift; F. Carney. 8 pp., 1 fig.

State geological surveys and practical geography; F. Carney. 6 pp.

Articles 6-10, pp. 61-188; April, 1909 $1.00

Fossils from the Silurian formations of Tennessee, Indiana, and Kentucky; Aug. F. Foerste. 56 pp., 4 plates.
Studies on Babbit and other alloys; 10 pp. J. A. Baker.

A statigraphical study of Mary Ann Township, Licking County, O. 28 pp., 15 figs. F. Carney.

Significance of drainage changes near Granville; Ohio; Earl R. Scheffel. 17 pp., 2 figs.

Age of the Licking Narrows; K. F. Mather. 13 pp., 5 figs.

Articles 11-16, pp. 189-287; June, 1909 $0.75

A spectrometer for electromagnetic radiation; A. D. Cole. 10 pp., 6 figs.

The development of the idea of glacial erosion in America; F. Carney. 10 pp.

Preliminary notes on Cincinnatian fossils; Aug. F. Foerste. 20 pp., 1 plate.

Notes on Spondylomorum Quaternarium Ehrenb; M. E. Stickney. 5 pp., 1 plate.

The reaction to tactile stimuli and the development of the swimming movement in embryos of Diemyctylus torsus,
Eschscholtz; G. E. Coghill. 21 pp., 6 figs.

The raised beaches of the Berea, Cleveland, and Euclid sheets, Ohio. F. Carney. 25 pp., 5 figs.

Articles 17-18, pp. 289-442; November, 1909 $1.00

Preliminary notes on Cincinnatian and Lexington fossils; Aug. F. Foerste. 45 pp., 5 plates.

The Pleistocene geology of the Moravia Quadrangle, New York; Frank Carney. 105 pp., 27 figs.

VOLUME 15

Article 1, pp. 1-100; March, 1910 $1,00

Bulletin in commemoration of Clarence Luther Herrick.

AUG. F. FOERSTE

The exact correlation of strata by means of fossils requires an
equally exact discrimination of these fossils into species and
varieties. Especially is this true of genera in which many of
the species are closely related. In the genus Calymene^ for in-
stance, almost any Ordovician species has been called C. senaria,
while almost any Niagaran species has been called C. niagarensis.
Recently Raymond (Bull. Mus. Comp. Zoology, Harvard Univ.,
60, 1, 1916, p. 27) has placed the Niagaran species on a better
footing. In a similar manner, the various species in the Cin-
cinnatian strata of Ohio, Indiana, and Kentucky need more
exact discrimination. Very little has been published on the
species of Isotelus in the Cincinnatian strata. Moreover, the
published figure of Encrinurus ornatus was altogether insufficient
for purposes of discrimination from closely similar forms found
in other strata. The following pages are intended as a contribu-
tion to a more exact discrimination of some of the closely
similar forms of the genera mentioned above.

Isotelus brachycephalus sp. nov.

Plates XIV, XIVA, and XV

Cephalon (plate XIV) 10.5 cm. in length along its median
line, and 26.3 cm. in width at the genal angles; the ratio of the
length to the width being four-tenths. The marginal border is
depressed or concave for a width varying from 13 mm. anteriorly
to nearly 20 mm. along the free cheeks. The facial suture is
outlined distinctly both anteriorly and posteriorly to the pal-
pebral lobes, and the position of these lobes is indicated, but the
course of the suture along the margin of the palpebral lobes can

65

66

AUG. F. FOERSTE

not be determined with certainty. Anteriorly the facial sutures
are almost marginal, being only 0.5 nun. distant from the an-
terior margin of the cephalon. They almost meet the anterior
margin of the cephalon, at points about 37 nun. on each side of
its median line. The length of the genal spines is not known,
but, judging from the width of their proximal ends, the tip of
these spines must have extended at least as far as the posterior
margin of the fourth segment of the thorax.

The length of the thorax (plates XIV and XIV A) along its
median line is 12.5 cm.; and its width is about 25.3 cm. There
are eight segments, as in other species of Isotelus in their adult
state. The width of the axial lobe is 10 cm. The broad median
groove along the proximal half of the pleural segments, and the
diagonal ridge crossing their more distal parts, are as in other
species of Isotelus.

The posterior end of the pygidium (plate XIV A) is not pre-
served, but its length is estimated at 13.8 cm., measuring from
the posterior margin of the thorax; its width is 24.8 cm.; the
ratio of the length to the width being about 55 per cent. Along
the antero-lateral angles the surface inclines abruptly down-
ward, forming a low ridge, posterior to which, proximally, there
is a broad groove, similar to that along the proximal parts of the
pleural segments of the thorax. The marginal part of the
pygidium is inclined downward and is slightly concave, the
width of this marginal part varying from 3.5 to nearly 4 cm.

The entire length of the specimen is 36.8 cm., the ratio of this
length of the entire individual to the width of the pygidium
being almost equal to the ratio of three to two; and the ratio of
this length to that of the pygidium alone equals that of twenty-
seven to ten. From this it is evident that the length of the
entire individual falls short of equalling three times the length
of the pygidium.

Locality and position. The large specimen of Isotelus de-
scribed above occurred at the western end of the excavation for
the conduit beneath the Huffman Conservancy dam, six miles
northeast of the center of Dayton, at an elevation of 745 feet
above sea, and 162 feet below the base of the Brassfield forma-

ISOTELUS, ACROLICHAS, CALYMENE, AND ENCRINURUS 67

tion. The trilobite was lying on its back, and it remained
attached to the upper half of the indurated clay layer in which
it was imbedded. Five feet above the trilobite horizon was
found a single specimen of Columnaria vacua Foerste. Since in
the northwestern quarter of the Waynesville quadrangle the
Hehertella insculpta layer, forming the base of the Liberty meni-
ber of the Richmond formation, lies about 165 feet beneath the
base of the Brassfield formation, the horizon at which the large
Isotelus at the Huffman Conservancy dam was found must be
either in the base of the Liberty member or near the top of the
Wajmesville member of the Richmond formation. The writer is
indebted to Arthur E. Morgan, chief engineer of the Miami
Conservancy District, for the privilege of studying this specimen.

At the bluff adjoining the southern end of the Huffman Con-
servancy dam the Brassfield limestone is underlain by the Elk-
horn clay shale, 60 feet thick, and this in turn by the White-
water member of the Richmond, but the line of contact of the
Whitewater with the Elkhorn could not be determined on ac-
count of the muddy clay adhering to the rock as the result of
continuous quarrying operations.

A second large specimen of Isotelus, apparently belonging to
the same species as the Huffman Conservancy dam specimen
was found by Dr. George M. Austin in the Isotelus clay layer in
the upper or Blanchester division of the Waynesville member of
the Richmond formation, at a locality about 2^ miles northeast
of Oregonia, in Warren County, Ohio. This locality is on
Roaring Run, about three-quarters of a mile northwest of the
Flat Fork school. The length of this specimen was 23.5 cm.
The original was an impression in clay, the trilobite lying on its
back, and of this impression Dr. Austin secured the plaster of
Paris cast, here illustrated on plate XV. In all essentials this
smaller specimen is similar to the larger specimen, described
above. The ratio of the length of the head to its width is as
five to ten. The ratio of the length of the pygidium to its width
is 58 per cent. The basal part of the genal spine on the right
side of the specimen is preserved, but its tip is gone, so that
there is no means of determining its exact length. It probably

68

AUG. F. FOERSTE

reached beyond the posterior margin of the third thoracic seg-
ment, possibly as far as the posterior margin of the fourth seg-
ment. In this specimen it is not possible to determine how close
the anterior parts of the facial sutures are to the anterior margin
of the cephalon, since they are not clearly differentiated here.
The state of preservation of the thoracic segments and of the
pygidium is excellent, and this is the chief reason for presenting
here a figure of this smaller specimen. In the collections at
Wilmington College, in Ohio, a cephalon occurs which has a
length, along its median parts, of 8.5 cm., and a width of 20
cm. This specimen evidently came from the base of the Liberty
formation, since the slab contains also columns of Glyptocrinus
richardsoni Wetherby, which is characteristic of that horizon. •

Remarks. Both the Huffman Conservancy dam specimen
and the Roaring Run specimen are characterized by cephalons
and pygidia which are remarkably short compared with their
width. This is true also of the Wilmington College specimen.

Only two species of Isotelus have been described from the
Richmond formation: Isotelus maximus Locke from the Liberty
member of the Richmond in Ohio, and Isotelus iowensis (Owen)
from the Maquoketa member in Iowa.

Isotelus iowensis is a much smaller species, 10 to 12 cm. long,
with’ much more elongate cephalons and pygidia, compared
with their width.

Isotelus maximus is founded on two specimens found in the
Liberty member of the Richmond formation a short distance
above the mouth of Treber’s Run, three-quarters of a mile
southwest of Duncanville, and 8 miles southwest of Peebles,
Ohio. Here the, two types were found by Dr. John Locke in a
strongly rippled layer of limestone, the ripples varying from 2
to 3 feet in distance from each other, and the troughs varying
from 2 to 3 inches in depth. Similar rippled layers of lime-
stone occur at higher elevations up the run. Both of the type
specimens were figured by Dr. Locke (Geol, Surv. of Ohio, 1838,
pp. 247-249, figs. 8, 9; see also fig. 1 and 2 on plate XVII of
this publication), and they are mentioned again in his descrip-
tion of Isotelus megistos Locke (Amer. Jour. Sci., 42, 1842, p.
366, pi. 3, fig.).

ISOTELUS, ACROLICHAS, CALYMENE, AND ENCRINURUS 69

The specimen described first by Locke consisted of a fragment
of the reflexed margin or doublure of the posterior part of the
pygidium; this fragment was 5 inches long and If inches wide,
and it was marked by veins,’’ but its curvature was so small
that it suggested ^The end of an ellipse 22 inches long and 12
inches broad.” The posterior termination of the axial lobe could
be recognized. All of these features are represented in figure
8, accompanying Locke’s original description of this species
(see also fig. 1 on plate XVII of this publication), but other
features are added so as to indicate the relative position of the
fragment in the pygidium. Essentially, nothing is known about
this type except that its posterior margin was of small curvature.
So little of the pygidium is preserved that it is impossible to
determine the ratio of the length of the latter to its width. As
a type it is worthless.

The specimen described second by Dr. Locke (fig. 9 accom-
panying his original description; see also figure 2 on plate XVII
herewith), consisted of an entire pygidium about 3| inches in
length, but this pygidium was enlarged by Dr. Locke to twice
its natural size, and a thorax and cephalon, based on Isotelus
megalops Green (Mon. Tril. N. Amer., 1832, p. 70, cast No. 25),
was added, producing a drawing 21 inches in length. Only the
pygidium of this drawing belongs to Isotelus maximus, and this
pygidium is distinctly more elongate and more triangular than
the pygidia of the Huffman Conservancy dam and Roaring Run
specimens described above, the ratio of length to width of Locke’s
specimen being about 65 per cent.

Although the more perfect pygidium, found by Dr. Locke,
was described and figured by him second, it is the only one of
the two specimens sufficiently complete to serve as a basis for
the identification of other specimens, the first specimen suggest-
ing merely large size but no other specific characters. On this
account figure 9 of Locke (fig. 2 on plate XVII of this publica-
tion) is chosen as representing the type of Isotelus maximus;
figure 8 may belong to the same species as the Huffman Conser-
vancy dam and Roaring Run specimens, described here, but
there is no means of determining this with certainty.

70

AUG. F. FOERSTE

Apparently there are two species of Isotelus present in the
Liberty and Waynesville members of the Richmond of Ohio
and adjacent states. One of these has more elongate cephalons
and pygidia, and is represented by the pygidium used by Dr.
Locke for his figure 9. For this species the name Isotelus max-
imus is retained. The second species, represented by the Huff-
man Conservancy dam and Roaring Run specimens, has rela-
tively shorter cephalons and pygidia and is regarded as a distinct
species for which the name Isotelus hrachycephalus is proposed.

A large pygidium of Isotelus resembling in outline that of Isotelus
maximus (fig. 9 of Locke), was found in the Stony Hollow,
northwest of Clarksville, Ohio, by Prof. S. R. Williams of Miami
University. Imbedded in the same slab is Hehertella insculpta,
and it was found at the extreme top of the Waynesville member
of the Richmond group. This pygidium is 5| inches long and
7 inches wide, thus indicating that Isotelus maximus actually
attains as large a size as Isotelus hrachycephalus, and is not con-
fined to the smallbr size usud by Locke for his figure 9.

It is customary to refer Isotelus megistos Locke (Amer. Jour.
Sci., 42, 1842, p. 366, pi. 3; see also plate XVI of this publica-
tion) to Isotelus maximus Locke. This is natural since Locke
himself included the two type specimens of Isotelus maximus
in his description of Isotelus megistos. However, the original
description of Isotelus megistos begins with a description of a
specimen found by Wm. Burnett on the hills at Cincinnati, and
this is the specimen figured on the plate accompanying Locke’s
paper. The horizon at Cincinnati apparently was not in the,
Richmond but in the upper half of the Maysville formation,
possibly in the Corryville. Compared with Isotelus hrachy-
cephalus both the cephalon and the pygidia of Isotelus megistos
are more elongate. The eyes are located nearer the posterior
margin of the cephalon, and the anterior parts of the facial
sutures are much more distant from the anterior margin of the
cephalon. The space between the facial sutures, anterior to the
eyes, is much more elongate. From this it seems evident that
the specimen described by Locke from the Cincinnati hills
belongs to a distinct species, for which the name Isotelus megistos
might be retained.

ISOTELUS, ACROLICHAS, CALYMENE, AND ENCRINURUS 71

Considering how abundant the fragments of large specimens
of Isotelus are at various horizons in the Richmond formation it
seems strange that .no attempt has been made to illustrate them
fully. Our knowledge of Isotelus maximus is confined to the few
notes and the meager illustrations presented by Locke in his
original publication. The numerous citations of Isotelus maxi-
mus from other authors concern chiefly closely similar, but prob-
ably not identical, Trenton forms. The Cincinnati species
described by Locke under Isotelus megistos also needs further
elucidation. It is hoped that the present publication of illus-
trations of Isotelus hrachycephalus, and the accompanying obser-
vations on Isotelus maximus and Isotelus megistos will stimulate
an interest in the large specimens of Isotelus occurring in Ordo-
vician strata.

Accompanying his original description of Isotelus maximus j
Locke pubhshed a figure of this species as though of an indi-
vidual 21 inches in length. His figure was based upon a py-
gidium of only half the size of that included in the figure, enlarged
so as to correspond in size to a second pygidium of which he had
only a fragment of the doublure. In a similar manner Clarke
published a figure of Isotelus maximus, from the Prosser lime-
stone at Mentorville, Minnesota (Geol. Minnesota, 3, pt. 2,
1894, p. 706, plate) as though of an individual 17 inches in length.
His figure was based on a fragment of a large glabella. Both
figures are based on estimates; both undoubtedly represented
large specimens of Isotelus; but actual figures and measurements
of large complete specimens are preferable, and an accumulation
of such figures and measurements is necessary before the large
forms of Isotelus can be discriminated successfully into species.

Both of the large specimens of Isotelus hrachycephalus, here
figured and described, were found lying on their back imbedded
in the middle of an indmated clay layer. In fact, all of the large
specimens of Isotelus found by Dr. George M. Austin in place in
the Richmond strata of Clinton and neighboring counties in
southwestern Ohio, between ten and fifteen in number, were
found imbedded in clay and lying on their back. Evidently the
specimens were covered by clay before decay dismembered the

72

AUG. F. FOERSTE

pleural segments of the thorax and permitted the free cheeks to
separate frum the cranidium. Very few specimens that re-
mained in their natural position escaped dismemberment during
decay. Dr. Welch, now dead, but formerly also a resident of
Wilmington, Ohio, found one of the few specimens ever seen
imbedded in a natural position in the rocks, but the parts of his
specimen were badly disarranged. These facts suggest a rapid
deposition of the clay layers in which the large specimens of
Isotelus were found.

In Cincinnatian areas thin layers of limestone, several inches
thick, frequently are interbedded with somewhat thicker layers
of clay, often a foot or more in thickness. The limestone layers
often consist of more or less comminuted fragments of bryozoans,
shells, and other organic remains, and are remarkably free of clay
except in very moderate quantities. Apparently the waters that
stirred up the organic fragments and removed the clays from the
future limestone layers kept these clays more or less in suspen-
sion and later permitted their deposition when the violence of the
motion of these waters had considerably diminished. In this
manner considerable quantities of clay may have been deposited
in relatively brief periods of time.

Little is known of sex differences among the trilobites. The
presence of both broad and narrow forms of Isotelus in the Rich-
mond strata of Ohio and Indiana suggests the possibility that
the more elongate forms {Isotelus maximus) may be the males,
and the broader forms {Isotelus hrachycephalus) the females of
the same species. Our present knowledge does not permit us to
determine with any confidence whether the differences noted are
connected with sexual differences or not.

ACROLICHAS

Ohio Journal of Science, XIX, 1919, p. 402.

For the American species at present referred to the European
genus Amphilichas, the generic term Acrolichas is proposed, on
account of differences in the structure of the pygidia belonging
to the American species. These pygidia have three pairs of ribs,

ISOTELUS, ACROLICHAS, CALYMENE, AND ENCRINURUS 73

all with free tips, but only the first two pairs of ribs bear me-
dian grooves ; moreover, the axial lobe narrows posteriorly to an
acute point which reaches the notch between the free tips of
the posterior pair of ribs. Lichas cucullus Meek and Worthen
(Plate XVII, Figs. 4 A,B) is chosen as the genotype. In the
Waynesville member of the Richmond formation, in Ohio, Acroli-
chas is represented by Lichas harrisi Miller, and a species with
coarser pustules is present in the upper part of the Liberty
member and the lower part of the Whitewater member of the
Richmond.

Acrolichas (?) shideleri sp. nov.

Plate XVII, Figs. 3 A, B

Two fragments, both interpreted as right free cheeks of some
Lichad. The general outline is falcate, but along the anterior
part of the outer margin of both fragments the curvature is
concave. Along its entire length, this outer margin is coarsely
striated, the width of the striated border varying from 2 mm.
near the posterior end of the free cheek to about 5 mm. along its
concave curvature. Posteriorly, these striae are directed diago-
nally outward and backward. Along the concavely curved
part, the striae bend up and down in an evenly concave manner.
The remainder of the free cheek, in each specimen, is coarsely
papillated, the apex of many of the papillae drooping diagonally
downward in a sort of ^Tear-drop” manner. The inner margin
of the tip of the free cheeks shows coarse striae, similar to those
along the outer border, but diverging only slightly from this
inner margin in direction; these striae can be seen only along the
posterior part of the inner margin, within 4 mm. from the tip of
the free cheek.

In one of these two fragments, the lower surface of the free
cheek was freed from the matrix. This surface is coarsely
striated with anastomosing lines, and at its proximal end it
shows the inner limit of the test on the lower side of the free
cheek. In removing the matrix, the anterior end of the free
cheek, with its concave outer margin, was broken off.

74

AUG. F. FOERSTE

Locality and 'position. At McDill Mill, about 6 miles north
of Oxford, Ohio, on the main branch of Four Mile creek, half a
mile northwest of the point where it is joined by East Fork.
In the lower part of the Whitewater member of the Richmond
formation, just above the Gyroceras haeri (Meek and Worthen)
bed. Found by Prof. W. H. Shideler, in whose honor the species
is named.

Remarks. The reference of these two free cheeks to Acro-
lichas is based chiefly upon their association in the same strata
with cranidia undoubtedly belonging to Acrolichas, and the fact
that these cranidia also bear coarse pustules. The pustules on
these cranidia are of two sizes; the conspicuous ones are large
and flat, and between these are others which are much smaller.
A cranidium found in the basal part of the Saluda, on Hanna
creek, one mile east of Liberty, Indiana, by Prof. W. H. Shideler,
apparenty belongs to the same species as the cranidia associated
with Acrolichas (?) shideleri.

A hypostoma of some species of Acrolichas, (plate XVIII, fig. 6)
possibly Acrolichas harrisi (Miller) was found by Prof. Shideler
just above the RhyncKotrema dentatum layer in the upper or
Blanchester division of the Waynesville member of the Rich-
mond, on Bull Run, less than a mile south of the railroad station
at Oxford, Ohio. The anterior, broadly T-shaped half of the
hypostoma is covered with numerous small pits. The lateral
parts of the hypostoma are striated longitudinally with flexuous
and more or less anastomosing lines. Along the posterior
median parts, the pits are very minute and distant.

Calymene abbreviata Foerste
Plate XVIII, figs. 5 A, B

Calymene abbreviata Foerste, Bull. Sci. Lab. Denison Univ., 16, 1910, p. 83, pi. 3,
fig. 17. Jour. Cincinnati Soc. Nat. Hist., 21, 1914, p. 148, pi. I, figs. 14 A, B.

The type of Calymene abbreviata was found in the Cynthiana
formation, one mile south of Roger's Gap, Kentucky. It is
characterized by the straightened, truncated anterior margin of
the glabella. The anterior two-fifths of the glabella tends to be

ISOTELUS, ACROLICHAS, CALYMENE, AND ENCRINURUS 75

quadrangular, but posteriorly the dorsal furrows diverge widely.
Along the anterior margin of the cranidium, the border equals
almost a third of the length of the glabella. Cranidia having
the same structure occur in the Rogers Gap member of the
Cynthiana formation, from Rogers Gap northward as far as
Sadieville, Kentucky.

A similar cranidium (plate XVIII, fig. 5 A, B) was found also
in the quarry east of Carnestown, on the Kentucky side of the
Ohio river. Here it occurred, associated with a single speci-
ment of Orthorhynchula linneyi, about 10 feet above the railroad,
and 56 feet below the base of the Fulton member, the latter
containing Triarthrus hecki. Forty- two feet below the level of
the railroad occur numerous specimens of Dalmanella hassleri,
Hallopora multitahulata, and occasional specimens of Stropho-
mena vicina, indicating the presence of typical Trenton strata,
such as occur in central Kentucky. Associated with the cra-
nidium mentioned above, occurred a single pygidium, with five
pairs of ribs, all of which, excepting those belonging to the last
pair, have the distal halves bifurcated by median grooves, as in
typical Calymena senaria.

Calymene sp. (Lorraine form)

Plate XVIII, fig, fi

At the Don Valley brick yards in the northeastern part of
Toronto, in Canada, strata occur which are referred to the lower
part of the Lorraine formation chiefly on account of the presence
of Trinucleus concentricus, Leptaena invenusta, and Catazyga
headi, all three associated in the same slabs. Among other
species occurring in these slabs are the following: Climacograptus
(Mesograptus) putillus, locrinus suhcrassus, Plectambonites seri-
ceus, Dalmanella sp., Zygospira modesta, PhoUdops suhtruncata,
Pterinea demissa, Byssonychia radiata, Lyrodesma poststriatum,
Modiolopsis cf. concentrica, Modiolopsis modiolaris, Cyrtolites
ornatus, Lophospira howdeni, Lophospira tropidophora, Sinuites
cancellatus, and a species of Arthraria 3 inches long.

With these fossils occurs a species of Calymene (Plate XVIII,
fig. 1) which resembles Calymene abhreviata in the shortness of

76

AUG. F. FOERSTE

its glabella and in the divergence of the dorsal furrows posteri-
orly, but differs in having a more rounded anterior margin on
the glabella, in this respect agreeing with Calymene meeki, a
species from the Maysville formation of Ohio, Indiana, and Ken-
tucky. In Calymene meeki the ribs of the pygidium show only
a trace of an impressed groove along their median line. The
pygidium of the Don Valley specimens is unknown.

Calymene retrorsa minuens var. nov.

Plate XYIII, fig. 4

Compared with Calymene meeki Foerste (Bull. Sci. Lab.
Denison Univ., 16, 1910, p. 84, pi. 3, fig. 18; also fig. 3 on plate
XVIII accompanying this paper), Calymene retrorsa Foerste
(Bull. Sci. Lab. Denison Univ., 16, 1910, p. 85, pi. 3, fig. 19;
also fig. 2 on plate XVIII herewith) is characterized by rounded
genal angles; a narrower, less triangular cephalon; and a shorter,
less nasute anterior border, in front of the glabella. Calymene
meeki is characteristic of the Maysville formation; and Calymene
retrorsa is characteristic of the Waynesville member of the
Richmond formation.

In the Whitewater member of the Richmond, both in Ohio
and Indiana, a small form of Calymene occurs which has all of
the characteristics of Calymene retrorsa but is constantly of
smaller size. For this form the varietal name minuens is pro-
posed. The specimen here figured (plate XVIII, fig. 4) was
obtained at Richmond, Indiana, by John Misener.

In Ohio, Calymene retrorsa minuens is found in Clinton county,
on a little branch entering Cowan creek, about a mile southeast
of the entrance of the latter into Todd’s Fork. Here the Liberty
member of the Richmond formation is 43 feet thick. In its
upper part, through a vertical range of 5 feet, Pachydictya
fenestelliformis is fairly common, and a large form of Strep-
telasma rusticum is abundant. The even-bedded character of
the Liberty member is continued into the lower part of the
Whitewater member for a distance of II feet. Above this level
the Whitewater strata become argillaceous and more or less
nodular, and specimens of Calymene retrorsa minuens begins to
make their appearance.

ISOTELUS, ACROLICHAS, CALYMENE, AND ENCRINURUS 77

Calymene sp. (West Union form)

Plate XVIII y figs. 8 B

The type of Calymene vogdesi Foerste (Bull. Sci. Lab. Denison
Univ., 2, 1887, p. 95, pi. 8, figs. 12, 16) is a large cranidium with
a broad, massive border, separated from the anterior part of the
glabella by a broad groove. The glabella is long, the dorsal
furrows are not strongly convergent, and the anterior margin of
the glabella has a broadly rounded outline. The accompanying
pygidia have five pairs of ribs. All ribs, except those belonging
to the last pair, are grooved for a short distance from the dorsal
furrow, and for a longer distance from the distal end of the rib.
Along the intermediate part of the ribs, the furrow is very faint or
entirely obsolete. This species is characteristic of the Brass-
field formation.

In the Holophragma zone at the top of the West Union forma-
tion at Hillsboro, Ohio, a much smaller species of Calymene
occurs, (Ohio Jour. Sci., XIX, 1919, p. 402, pi. 18, fig. 6) about
three-fifths as large as typical Calymene vogdesi. It has about
the same form of cranidium, but the anterior half of the glabella
is more quadrangular and is truncately rounded anteriorly; the
anterior margin of the cranidium is relatively broad, but there is
no broad groove separating this border from the anterior margin
of the glabella, as in Calymene vogdesi.

In the Trimerus (formerly referred to Homalonotus) delphino-
cephalus zone, about 10 feet above the base of the West Union
formation, at the quarry in the southeastern corner of West
Union, Ohio, cranidia (figs. 8 A, B, on plate XVIII of this Bulle-
tin) were found which closely resemble those from the Holo-
phragma zone mentioned above. They differ chiefly in having
a narrower anterior border, which bends more strongly upward,
so that, from above, this border appear's more narrow than its
actual width. The accompanying pygidia show five pairs of
ribs, the grooving of which can not be determined from the
specimens at hand.

78

AUG. F. FOERSTE

Calymene niagarensis Hall

Plate XVIII, figs. 12 A, B

Specimens from the Rochester shale of New York, furnished
by the New York State Museum, through Dr. Ruedemann,
have glabellae with a somewhat swollen frontal lobe, elevated
rather abruptly above the frontal margin. The articulating
margin along the anterior of the pygidium curves outward from
the axial lobe and then backward to the posterior margin. When
the axial lobe is placed in a horizontal position the posterior
margin of pygidium appears rounded or slightly angular. The
axial rings are transverse, about 7 in number, leaving only a
very short posterior undifferentiated end.

Calymene breviceps Raymond
Plate XVIII, fig. 7

Calymene breviceps Raymond, Bull. Mus. Comp. Zool. Harvard Univ., 60, 1916,

p. 27, pi. 3, fig. 11.

Specimens of the Calymene which is common in the Waldron
shale at Newson, Tennessee, compared with typical Calymene
niagarensis, have a somewhat flatter frontal lobe on the glabella,
and this frontal lobe rises less above the anterior margin of the
cranidium. The axial lobe of the pygidium has more convergent
sides; the axial rings are curved, especially the anterior ring.
When the axial lobe is placed in a horizontal position, the pos-
terior margin of the pygidium is less curved and frequently has
an almost transverse outline.

Calymene cedarvillensis sp. nov.

Plate XVIII, figs. 11 A, B, C

In the Cedarville dolomite, in the quarry at Cedarville, Ohio,
a large species of Calymene is found, equalling Calymene vogdesi
in size. The only complete specimen found, more or less dis-
torted by pressure along its right side and along its anterior

ISOTELUS, ACROLICHAS, CALYMENE, AND ENCRINURUS 79

margin, originally must have been nearly 95 mm. in length.
The glabella has about the same structure as the glabella of the
other Silurian species here described; it is relatively long, the
anterior part tends to be quadrangular, and the dorsal furrows
do not diverge strongly posteriorly. The chief difference from
Calymene vogdesi consists in the narrower anterior border which
is not separated from the anterior part of the glabella by a groove
distinct from the general curvature of the border. Compared
with Calymene celehra Raymond (Bull. Mus. Comp. Zool. Har-
vard Univ., 60, 1916, p. 28, pi. 3, figs. 9, 10) its anterior border
is considerably wider. Of the pygidium not much is known, but
the shallow groove along the top of the' ribs appears nearer the
posterior margin of these ribs, at least along their distal half.

All of the Trenton and Cincinnatian species of Calymene in
American strata known to the present writer have the abbre-
viated form of glabella, with the strongly divergent dorsal fur-
rows. All of the Medinan and Niagaran species have the more
elongate form of glabella, with the more moderately divergent
dorsal furrows. The Trenton species include Calymene senaria
Conrad, and Calymene abhreviata Foerste. The Cincinnatian
species include Calymene granulosa Foerste, C. meeki Foerste,
C. retrorsa and variety minuens Foerste, C. fayettensis Slocom,
and C. gracilis Slocom. Calymene callicephala Green may have
been founded on a poorly preserved erratic specimen of Calymene
senaria. The Medinan species include Calymene vogdesi Foerste,
and the Niagaran species include Calymene niagarensis Hall,
C. hreviceps Raymond, C. celehra Raymond, and C. cedarvillensis
Foerste.

Encrinurus ornatus Hall and Whitfield
Plate XVIII, figs. 9 A, B

Encrinurus ornatus Hall and Whitfield, Pal. Ohio, 2, 1875, p. 154, pi. 6, fig. 16.

The type of Encrinurus ornatus was found in the Cedarville
dolomite at Cedarville, Ohio. It is doubtful whether this species
occurs at any other horizon than in the Cedarville dolomite,
although closely similar forms occur at other horizons. This
species is found in the Cedarville dolomite not only at Cedar-

80

AUG. F. FOERSTE

ville but also at the Moody quarry, in the southeastern part of
Wilmington, Ohio, from which specimens occur in the collection
of T3r. George M. Austin. The pygidium, in the best preserved
interior cast found in this collection, figured herewith, has 7
pairs of ribs, of which the last pair is very short and is indicated
chiefly by the nodular elevation of part of this rib. A cast of
the exterior of another specimen suggests the possibility of an
eighth pair of ribs, but this is doubtful. The chief character-
istic of the species, as far as known, is found in the curvature of
the ribs. The axial lobe is almost straight from front to rear.
From this lobe all of the anterior ribs diverge strongly, and
the backward curvature of their distal halves is more moderate
than in any other Silurian species. The posterior termination
of the pygidium of this species is unknown.

In Encrinurus reflexus Raymond (Bull. Mus. Comp. ZooL,
60, 1916, p. 25, pi. 3, figs. 7, 8) from the Niagaran at Wauwatosa,
Wisconsin, there are 8 pairs of ribs, and these are deflected more
strongly toward the rear.

Encrinurus hillsboroensis sp. nov.

Encrinurus cf. ornatus, Ohio Jour. Sci., 1919, p. 391, pi. 18, figs. 2 A-C.

In the Holophragma zone, at the top of the West Union for-
mation, at Hillsboro, Ohio, fragments of a species of Encrinurus
occur which differ from either Encrinurus ornatus^ or Encrinurus
reflexus in the strong posterior reflexion of the distal parts of the
ribs on the pygidium. There are 8 pairs of ribs and the pygidium
terminates posteriorly in an acute spinose end. It is probable
that a similar termination would be found also on the pygidia of
other species if these parts were preserved.

In Encrinurus thresheri Foerste (Bull. Sci. Lab. Denison Univ.,
2, 1887, p. 101, pi. 8, fig. 26; also pL XVIII, fig. 10 of present
issue) the ribs curve strongly backward as in Encrinurus hills-
horoensis, but there are only 6 pairs of distinctly defined ribs,
with a doubtful seventh pair parallel to the posterior end of the
axial lobe. The type apparently is a cast of the lower surface
of the pygidium, which accounts for the apparent narrowness of
the ribs.

ISOTELUS, ACROLICHAS, CALYMENE, AND ENCRINURUS , 81

ADDITIONAL NOTES ON BRASSFIELD ECHINODERMATA

Since the publication of the article on the echinodermata of
the Brassfield Formation, in the earlier part of this volume,
Mr. Frank Springer, the eminent American authority on Cri-
noidea, has kindly offered the following notes on several of the
specimens there figured.

The broad, flat calyx, represented by figures 2 A, B, C, and D on plate Vl,
belongs to the Rhodocrinidae, and may be similar to the form described by
Weller, from the Racine of the Chicago area, as Archaeocrinus depressus.
Hitherto we have supposed- this genus to be purely Trenton and Chazyan, but
the Racine and Brassfield forms appear to be close to it.

The specimen retaining both calyx and arms, obtained at the Centerville
quarry, and forming figure 3 on plate III, is of the type PaielUocrinus Angelin,
one of the rare Gotland forms, but the preservation of the Centerville specimen
is tantalizing, and one does not feel sure of the structure.

The fragments of calyx and arms forming figures 4 A, B, on plate III, also
found at the Centerville quarry, apparently belong to the Flexihilia, and very
probably is Pycnosaccus , as far as can be determined in the absence of an
entire calyx.

The problematical specimen described on page 28 as Stereoaster squamosus
forms the genotype of Stereoaster, the latter being a new generic term, a fact
not indicated in the text at the time of its original publication.

PLATES XIV AND XIV A

Isotelus brachycephalus sp. nov.; type. An entire individual, figured in two
parts, reduced in size. The cephalon and the five anterior segments of the thorax
are shown on plate XIV ; the pygidium and the three posterior segments of the
thorax are shown on plate XIV A. The former presence of a genal spine is seen
on the left side of the cephalon. The length of this spine is unknown. Parts
of the reflexed lower margins of the free cheeks and of the pygidium are seen on
the left side of the specimen. Found in the base of the Liberty or the top of the
Waynesville member of the Richmond, at the Huffman Conservancy dam, 6 miles
northeast of the center of Dayton, Ohio. Loaned by Arthur E. Morgan, Chief
Engineer.

Bulletin Scientific Laboratories Denison University Vol. X\X

PLATE XIV

FOERSTE : ORDOVICIAN TRILOBITES

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE XIV A

FOERSTE: ORDOVICIAN TRILOBITES

PLATE XV

Isotelus brachycephalus sp. nov. A cast showing the upper suHace of an
entire individual, in a remarkably good state of preservation; figure reduced
in size. Found in the upper or Blanchester division of the Waynesville member
of the Richmond, about 2| miles northeast of Oregonia, Ohio, on Roaring Run,
by Dr. George M. Austin.

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE XV

FOERSTE: ORDOVICIAN TRILOBITES

PLATE XVI

Isotelus megistos Locke; type specimen, described and figured in the Amer-
ican Journal of Science, vol. 42, in 1842; p. 366; pi. 3. Found by Wm. Burnett on
the hills at Cincinnati, Ohio, presumably in the upper part of the Maysville
formation.

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE XVI

FOERSTE: ORDOVICIAN TRILOBITES

PLATE XVII

Fig. 1. Isotelus maximus Locke; one of the types figured by him in Geol. Surv.
Ohio, 1838, pp. 247-249, plates 8 and 9. As the first published figure, this should
be the type, but of this entire figure only that part was based on an actual speci-
men which is included in the marginal part of the pygidium, where the lower,
reflexed doublure is shown by the removal of the upper part of the pygidium.
This part is not regarded as sufficient to determine the outline of the pygidium.
All of the remainder of the drawing was added to ‘^place’The fragment in its
proper surroundings in the pygidium. Found in the Liberty member of the
Richmond, on Treber Run, 8 miles southwest of Peebles, Ohio.

Fig. 2. Isotelus maximus Locke; the second one of the types figured by Locke,
as figure 9, found at the same locality and horizon as the preceding specimen.
Copied from the enormous figure, 21 inches long, presented by Locke. This
figure was based on a single pygidium, much smaller than the figure, the outline
being based on the entire pygidium at hand and the size being enlarged so as to
conform with the imagined size of the individual of which figure 8 illustrates only
a fragment. Probably two species are represented by figures 8 and 9 of Locke.
Of these, figure 9 is the only one including enough of an individual to make pos-
sible the identification of the type. In the opinion of the writer, either Locke’s
name, maximus, should be dropped or the name should be attached to the speci-
men represented by figure 9, which there is some chance of identifying, in the
entire absence of Locke’s types.

Fig. 3. Acrolichas (?) shideleri sp. nov. A, upper surface of a fragment re-
garded as a free cheek. B, under surface of a second, similar free cheek. Found
in the Whitewater member of the Richmond, at McDill’s Mill, 9 miles north of
Oxford, by Prof. W. H. Shideler.

Fig. 4. Acrolichas cucullus ottawaensis var. nov. A, cranidium; B, pygidium.
From the Trenton at Hull, opposite Ottawa, Canada. Collected by J. E. Narra-
way. Differing from the type chiefly in the rounded free tips of the ribs on the
pygidium.

Bulletin Scientific Labcratories Denison University Vol. XIX

PLATE XVII

FOERSTE; ORDOVICIAN TRILOBITES

PLATE XVIII

Fig. 1. Calymene sp. (Lorraine form). Enrolled individual from Lorraine
formation at Don Valley brickyards at Toronto, Canada.

Fig. 2. Calymene retrorsa Foerste. Lateral view of type; see Bull. Sci. Lab.
Denison Univ., 16, 1910, p. 85, pi. 3, fig. 19. From middle or Clarksville division
of Waynesville member of Richmond formation, on Silver Creek, east of Dun-
lapsville, Indiana.

Fig. 3. Calymene meeki Foerste. Lateral view of type; see Bull. Sci. Lab.
Denison Univ., 16, 1910, p. 84, pi. 3, fig. 18. From Fairmount member of Mays-
ville formation, at Cincinnati, Ohio.

Fig. 4. Calymene retrorsa minuens Foerste. Enrolled specimen, from White-
water member, at Richmond, Indiana, collected by John Misener.

Fig. 5. Calymene abbreviata Foerste. A, cranidium; B, pygidium, with
posterior part preserved. From Cynthiana formation at quarry east of Ivor,
Kentucky.

Fig. 6. Acrolichas harrisi (Miller) (?). Hypostoma; found in Blanchester
division of Waynesville member of Richmond formation, on Bull Run, southwest
of Oxford, Ohio, by Prof. W. H. Shideler.

Fig. 7. Calymene breviceps Raymond; the posterior part of the occipital ring
is broken off. Glabella. From Waldron shale at Newsom, Tennessee.

Fig. 8. Calymene sp. (West Union form). A, cranidium; B, pygidium. From
the Trimerus delphinocephalus zone, ten feet above the base of the Bisher mem-
ber of the West Union formation.

Fig. 9. Encrinurus ornatus Hall and Whitfield. A, pygidium, with the pos-
terior tip missing; B, lateral view of same. From the Cedarville dolomite at the
long abandoned quarry southeast of Wilmington, Ohio, west of the county
infirmary.

Fig. 10. Encrinurus thresheri Foerste. Pygidium, with the posterior tip not
clearly exposed, and with the anterior margin of the axial lobe missing; both
restored. Type; see Bull. Sci. Lab. Denison Univ., 2, 1887, p. 101, pi. 8, fig. 26.
From the Brassfield formation, at Dayton, Ohio.

Fig. 11. Calymene cedarvillensis Foerste. A, entire individual with right
side and anterior margin distorted by crushing; B, part of cranidium; C, frag-
ment of another cranidium. From the Cedarville dolomite at Cedarville, Ohio.

Fig. 12. Calymene niagarensis Hall. A, cephalon of enrolled specimen; B,
lateral view of extended specimen. From the Rochester shale of New York,
loaned from the New York State Museum, at Albany, through the courtesy of
Dr. Rudolph Ruedemann.

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE XVIII

FOERSTE: ORDOVICIAN AND SILURIAN TRILOBITES

SOME SUGGESTED EXPERIMENTS FOR THE GRAPHIC
RECORDING OF SPEECH VIBRATIONS

ROBERT JAMES KELLOGG

In an attempt to recast the science of phonetics on the basis
of connected speech flow,^ I have found it necessary to criti-
cally compare the results obtained by different methods of
graphically recording speech vibrations. Out of this comparison
a number of suggestions have emerged (1) for further perfecting
certain existing types of apparatus, (2) for the application of
apparatus already perfected to special linguistic problems, and
(3) for the development of new types of apparatus in which the
^Tight-lever’’ (or shifting ray of light responding to sound vibra-
tions) partly or wholly replaces the physically vibrating parts.

These suggestions are presented herewith in the hope that they
may be of interest and help to other investigators, and also that,
if a larger number can cooperate in working them out, the prac-
tical and mechanical difficulties involved may be the sooner
solved and the apparatus based on these principles devised and
perfected.

I. THE PERFECTING OF EXISTING TYPES OF APPARATUS

It cannot be too strongly insisted that the mechanical per-
fection of diverse types is necessary if the problems of experi-
mental phonetics are to be fully solved. Every type of sound
recording apparatus distorts the sound curves in its own special
way, suppressing, damping, modifying or adding specific vibra-
tional elements. Even in the perfected apparatus this distor-
tion may either require complicated correction of results (as in
the phonodeik), or it may not be fully determinable from the
unaided standpoint of the apparatus in question (as in the case

^ Proc. Mod. Lang. Assoc., 1915, p. xxix, title 46: About face in fonetics.

83

84

ROBERT JAMES KELLOGG

of the manometric flame). But the results of diverse types of
apparatus check and interpret each other. Thus in the case of
the two types just mentioned^ the phonodeik^ gives legible
sinusoidal records of even the minutest elements and phases of
vibration^ showing distinctive curves even of voiceless con-
sonants and whisper sounds ^ but its records require varied and
complicated corrections of horn and diaphragm effects. ^ The
manometric flame as developed by Nichols and Merritt^ is non-
sinusoidal in its record and therefore hard to interpret^ but it is
apparently freer than any other apparatus from special muf-
flings and reinforcements. It is equally able to show the highest
and minutest vibrational elements and* phases.® Apparently
therefore these two types of apparatus are complementary^ each
approaching perfection where the other is most defective.

Furthermore, it is impossible to forecast either the kind or
value of results obtainable with any type of apparatus until it is
perfected and its results thoroughly tested out. Thus, the
phonograph and gramophone are merely perfected forms of
Scott^s crude phonautograph, which, though it has failed thus
far to produce the visible graphic record originally sought, pro-
duces in these perfected forms practically perfect results in a
new and unforeseen direction. Nichols and Merritt^s mano-
metric flame apparatus shows that Koenig’s manometric figures
consisted of partly overlapping images, which effectively con-
cealed all minor phases of vibration, but that with a vibrating
flame of high actinic power and high speed of the recording
fihn, these figures are resolved and the minutest phases and
shades of vibration clearly recorded. The phonodeik, with its
marvellous sensitiveness to the minutest and most rapid vibra-
tory movements, shows an equally marked advance over the
cruder instruments of the same type developed by Blake, Argollot
and Chavanon, Lebedeff, and Somojloff. Thus the three types

2 Miller, Science of Musical Sounds. New York, 1916.

^ Ibid., figs. 170, 171, 172, 184; Phys. Rev., xxviii, 151 ff.

4 Ibid., ch. y,

5 Phys. Rev., i, 166-176, and vii, ,93-101.

® See illustrations under the second article cited in note 5.

GRA.PHIC RECORDING OF SPEECH VIBRATIONS

85

of apparatus (phonograph, phonodeik and manometric flame)
which have been brought nearest to mechanical perfection, have
all been developed out of exceedingly defective and seemingly
unpromising types. It is therefore precarious to reject any
type of apparatus on a-priori grounds, and surely worth while
to study the problem of perfecting existing types of apparatus
and devising new ones.

Enlargement of phonographic and gramophonic records. It is
highly probable both on practical and theoretic grounds that
the direct phonautograph type cannot be perfected to produce
accurate sound curves large enough for direct reading. This
appears both from the negative results attending long years
of efforts and experiments directed to improving the pho-
nautograph, ^ and from the fact that the degree of magnification,
the inertia, length and flexibility of levers, and the amplitude of
vibration demanded at the recording point are so great that the
physical mechanism cannot conform to the rapid and com-
plexly changing phases of speech vibration, and also necessarily
introduces interfering vibrational elements of its own. But in
the form of the phonograph and gramophone, the phonauto-
graph has been brought to approximate mechanical perfection for
the production of audible records, and the phonograph and
gramophone grooves are therefore approximately perfect phys-
ical records of speech vibrations on a microscopic scale. Various
means of enlargement have been tried in the effort to render the
sound grooves legible.

Direct magnification^ of the sound groove has thus far proved
unsatisfactory for the phonograph and impossible for the gramo-
phone. In the phonograph groove the sinusoidal element is
perpendicular to the surface and therefore in the line of sight,
and hence disappears both in direct microscopic observation by
the eye and in microphotographic enlargement. The gramo-
phone groove is indeed sinusoidal in the plane of the record, but
the length of the sinusoids is so great in comparison with their

^ Scripture, Elements of Experimental Phonetics. New York, 1902, pp. 17-24.

® Cf. Marichelle, La parole d!apres le trace du phonographe. Paris, 1897.
See also Boeke in Pflueger's Archiv, 1891, p. 297.

86

ROBERT JAMES KELLOGG

amplitude that they are wholly illegible on any scale of enlarge-
ment. In other words, the difficulty rests for both instruments
in the fact that the record is not made for visible but only for
audible purposes. The remedy obviously lies in constructing
phonograph and gramophone records for the express purpose of
microscopic enlargement without regard to their fitness for
audible reproduction (though a synchronous audible record
could also be made for comparison if desired).

In the case of the phonograph, a micro-legible record could be
made by using a wedge-shaped cutting sapphire (that is, one
with two straight cutting edges meeting in a' point) , thus making
the depth and width of the groove proportional and the edges
true sinusoids of the sound vibrations recorded, and as such
capable of direct microscopic enlargement and photographic
reproduction and interpretation. Whether it could be made
more easily legible and photographable by a surface coloring of
the wax, could be determined by trial.

In the case of the gramophone, a micro-legible record could
easily be made by sufficiently reducing the speed of the record-
ing disk, thus foreshortening the vibrational curves to legible
sinusoids. Such a record ought to be easily magnifiable suffi-
ciently to show the minutest phases of vowel and consonant
vibrations.

The unsatisfactory results hitherto attending microscopic
enlargement of *the sound groove led to various efforts at indirect
enlargement, either by physical levers (as by Scripture,^ Muen-
zinger^® and others), or by physical and light-levers combined
(as by Hermann,^^ Rosset^^ ^nd others).

Scripture apparently carried the simple lever apparatus to
the limit of its possibilities. He himself adjudges it inadequate
and believes that ^Hhe future of the method lies in the develop-

® Elements of Experimental Phonetics, ch. IV, and Study of speech curves,
Washington, 1906, ch. II.

Bull, of Univ. of Texas, no. 24, April, 1915.

See Elements of Experimental Phonetics, p. 38 ff, with the references there
given.

Recherches experimentales pour I’inscription de la voix parlee. Paris, 1911.

GRAPHIC RECORDING OF SPEECH VIBRATIONS

87

ment of a compound lever.^’i^ He believes this inadequacy is
due to the low degree of magnihcation obtainable (125 to 300
times). But a comparison of his results with those of Hermann,
Rosset, Marichelle and Miller, shows that the failure of Scrip-
ture’s apparatus to record consonantal and overtone vibrations
is due to its low limit of sensitiveness and not to its low degree
of magnihcation. Thus Marichelle shows the occlusive and
explosive phases of voiceless consonants with a magnihcation of
less than thirty diameters.^^ Miller’s record of Lowell Institute
as recorded in his Science of Musical Sounds^^ has a magnihca-
tion only a little greater than that given by Scripture’s appa-
ratus, but it plainly shows the vibrations of even the occluded
phases of s and t.

Muenzinger’s compound lever apparatus neutralizes the
weight of all levers through counterbalancing, and practically
eliminates play and friction of bearings and joints by point or
V-bearings. His hrst results do not exceed those obtained with
Scripture’s simple lever apparatus. Muenzinger’s apparatus
ought to be further developed and perfected in order to deter-
mine its full possibilities. Apparently any further progress in
physical lever magnihcation of the sound groove must follow
the lines that he has laid down. The future of the method must
lie, not in seeking greater magnihcation as Scripture supposed,
but in seeking greater sensitiveness, perhaps with lower magnih-
cation if that is necessary to secure it. The absorption of
minute vibrational phases (due in Scripture’s apparatus to play
of bearings, inhnitesimal bending of levers, and friction of the
recording stylus) must be eliminated. Muenzihger’s V-bearings
will probably solve the hrst difficulty. The bending can perhaps
be eliminated by using very light levers with delicate trussing
or wire bracing, which are kept at a hxed temperature; the
method probably cannot be perfected unless such rigid and
delicate levers can be obtained. For the recording surface some

■ Study of Speech Curves, p. 26.

La parole d’apres le trace du phonographe, figs. 83-86, p. 80.

Figure 184, p. 254.

88

ROBERT JAMES KELLOGG

substance or surfacing approaching absolute smoothness must
be sought.

Decidedly better results have been obtained by the combina-
tion of physical levers with light-levers. Hermann's work on
this line (cited above) is well known. It is worth while, how-
ever, to call especial attention to Rosseks apparatus. A tiny
concave mirror attached to the reproducing stylus of the phono-
graph reflects a beam of light to the recording screen, thus giv-
ing synchronous graphic and auditory records of the sound
waves, the latter record testing and interpreting the former, and
enabling him to perfect his apparatus. Fuller details of his
method are given in his Recherches experimentales, cited above.
For want of adequate funds, his experiments were confined to
working out the principle. With a lateral magnification of 250
times, he secured distinctive records not only of vowels, voiced
consonants and spirants, but also of explosive t, of on and off
glides in connected speech, and of the gradually changing form of
.the so-called simple vowels. His apparatus is probably capable
of being brought to an extreme degree of delicacy and perfec-
tion, and the principle he uses may be capable of other applica-
tions. It would be well if some of ' our American laboratories
could help in this development.

Sinusoidal manometric flame records. One other type of re-
cording apparatus probably capable of being more fully per-
fected is the sinusoidal manometric flame record of J. G. Brown.
The direct non-sinusoidal form of the manometric flame has
been approximately perfected by Nichols and Merritt, as noted
above. Brown succeeded in obtaining a sinusoidal record by
turning the exit tube of the manometric capsule on a downward
slant, thus obtaining a curved flame with its outer portion curv-
ing upward and describing up and down harmonic motions with
the variations of vibratory pressure in the manometric capsule.
By using a clear actinic flame good photographic records of the
flame sinusoids were obtained, as shown in illustrations in the
article just cited. By using a smoky flame a sinusoidal record

Phys. Rev., xxxiii, 442-446.

GRAPHIC RECORDING OF SPEECH VIBRATIONS

89

was deposited in soot on a revolving tambour. But the soot
record is not wholly satisfactory because different portions of the
flame deposit separate superposed records not wholly agreeing
in form, as only the lower edge of the flame gives a true sinusoid.
So far as published, Brown’s apparatus was applied only to a
few simple vowel sounds and its power of recording finer and
higher speech sounds remains to be tested. But the extreme
sensitiveness of the manometric flame as demonstrated by
Nichols and Merritt, makes it probable that his apparatus could
be developed and used along this line. It would therefore be
of the utmost importance if this method could be so developed
as to eliminate the superposed soot figures and give a single
clear sinusoidal line. Perhaps this could be effected by using a
generally clear flame in which a single tiny soot-producing source
is introduced, and from which a fine line of soot would continu-
ously pass to the recording tambour. If the method can be thus
perfected, it would give a cheap, efficient and manageable way
of producing clear and legible records of connected speech.
How important this would be will appear plainly if we reflect
that even our best equipped and endowed laboratories find
serious mechanical and financial difficulties in making extensive
records of connected sentences and words. To be legible the
sinusoids must not be foreshortened, and when this condition
is fulfilled, the record of even a single syllable becomes several
feet long, complete words and sentences correspondingly longer,
while a discourse may be measured by the mile. The mechanical
difficulty and expense of producing photographic records on this
scale is prohibitive. Hence the importance of developing a
cheap and efficient means of producing extensive permanent
records of connected speech. It would seem to be worth while
for different laboratories to cooperate in experiments directed
to this end.

II. APPLICATION TO SPECIFIC PROBLEMS

As to the application of perfected types of apparatus to specific
linguistic problems, the chief need is undoubtedly a more exten-
sive and intensive study of the phenomena of colloquial speech

90 EGBERT JAMES KELLOGG

— not merely of intoned vowels or selected syllables or formally
enunciated phonographic records, but of actual spoken language
in the setting of actual life. If, for instance, the phonodeik,
either alone or in conjunction with the manometric flame, could
be used to make as careful a study of the spoken language of
many different persons, as it was used to make of intoned vowels,
it would likely solve many important problems. Note further
how many types of apparatus have been barely developed and
demonstrated, but for lack of funds never applied to the solu-
tion of urgent phonetic problems. Cases in point are the mano-
metric apparatus of Nichols and Merritt and of J. G. Brown,
Muenzinger’s compound lever apparatus and RosseCs syn-
chronous recording and reproducing apparatus, all of which were
noted above. When we consider that' language is the vehicle of
all of human life and institutions and of all of our knowledge
and study of the outside world, it may be reasonably contended
that no other single phenomenon is a more important object of
investigation. The scientific study of its different phases has
already yielded writing, printing, telegraphy, the telephone, and
the phonograph, besides making important contributions to
psychology and physiology, as in the case of the doctrine of
cerebral localizations which is a part of the basis of modern
surgery. It is devoutly to be hoped that more nearly adequate
provision may be made for the scientiflc study of language in all
its phases. To which of our institutions of learning and research
will fall the honor of leading in such a movement?

III. NEW TYPES OF APPARATUS

As to the development of new apparatus of the light-lever
type, I would suggest two principles, to which we may provision-
al y give the names of sonoscope and sonograph, the first in-
volving the elimination of all physical levers but retaining a
receiving horn andMiaphragm, the second eliminating all reso-
nating and physically vibrating parts, and using a light-lever

Science of Musical Sounds, chs. VII and VIII.

GRAPHIC RECORDING OF SPEECH VIBRATIONS 91

whose initial deflection is obtained by refraction as it passes
through free sound-transmitting air. The purpose is to develop,
if possible, an apparatus combining great sensitiveness and high,
magnification with minimum distortion, and constructible at
moderate expense in the average laboratory of limited means
and equipment.

The sonoscope. The principle of the sonoscope is shown in
three forms in figures 1, 2 and 3. It consists essentially of a
receiver horn H, with a thin mirror-diaphragm D (probably of
silvered glass or mica, or perhaps of polished metal) from which

P

Fig. 1. Principle of the Sonoscope, Form A (Horizontal Section)

a ray of light (or light-lever) R is reflected to the demonstration
screen or photographic film P. The ray is received through the
pinhole aperture A, focussed by the lens Li, falls at an oblique
angle (say 30 degrees) on the vibrating mirror-diaphragm, whose
varying vibratory positions DD' shift the ray to varying paths
RR'. These paths are nearly parallel or slightly divergent with
an extreme separation of perhaps 0.005 or 0.010 of an inch,
more or less, according to the amplitude of vibration which

If either of these principles proves successful, acknowledgment will be due
to Prof. D. C. Miller, as the ideas were partly suggested to me by the phonodeik.

92

ROBERT JAMES KELLOGG

proves feasible for the diaphragm. The divergence of the
paths RR' is increased by refraction or reflection, thus causing
the ray or light-lever to describe on the screen P an enlarged
representation of the vibratory movements of the diaphragm D,
In form A (fig. 1), the paths RR' are made convergent by a
lens of crossed glass or quartz fibers L2L3, whose proper radius
of curvature (perhaps from 0.01 to 0.02 of an inch) must be
experimentally determined. The paths RR' diverge again
beyond the crossing point C, and when sufficiently far apart,
have their rate of divergence increased by the concave lens L4
(or by a convex glass-tube mirror, which can be made in the

V

Fig. 2. Principle of the Sonoscope, Form B (Horizontal Section)

laboratory). The exact location of the various lenses must be
such as to focus approximately the light-lever R on the screen
P. The first focus of lens Li must fall between the diaphragm
D and the fiber lens L2L3; the second focus P2 of the lens L2L3
will fall beyond the crossing point C, because divergence within
the ray before reaching the fiber lens L2P3 is greater than that
between its paths RR', The concave lens (or convex mirror)
L4 must be placed between the crossing point C and the second
focus F2, thus prolonging the focus to P3 on the film or screen P.

In form B (fig. 2), a convex glass-tube mirror M replaces the
lenses L2L3 and Li of form A. The first focus Pi must fall be-

GRAPHIC RECORDING OF SPEECH VIBRATIONS

93

yond the mirror M, which prolongs the focus to on the screen
P. Other factors are as in form A. It may be found advisable
also to try two glass-tube mirrors instead of one. For the pos-
sible arrangement in that case, compare the place of the two
mirrors in form B of the sonograph in figure' 5.

In form C (fig. 3), a concave lens L2 replaces the mirror M
of form B. Other details are as in form B. The lens L2 would
have to be very small and might therefore be more difficult to
obtain and adjust than the glass-tube mirror. Form C there-
fore seems to offer less promise of success than forms A and B.

F

Fig. 3. Principle of the Sonoscope, Form C (Horizontal Section)

The sonograph. The principle of the sonograph is shown in
figures 4, 5 and 6. It consists of a sound-proof cylinder SC and
S'C' completely cut across by an oblique opening 00 comprised
between two parallel planes. A ray of light R passing throug
the aperture A and the collecting lens L], all in the first section
of the sound-proof cylinder SC, thence passes through a paral-
lelogram prism Pti into the opening 00, through a second prism
Pr’2 into the second sound-proof section S'C', where it passes
through diverging lenses or mirrors to the screen or film PP.
The ray R is refracted away from the perpendicular as it passes

94

ROBERT JAMES KELLOGG

Fig. 4. Principle of the Sonograph, Form A (Vertical Section)

S 0 S' ?

Fig. 5. Principle of the Sonograph, Form B (Vertical Section)

Fig. 6. Principle of the Sonograph, Form C (Vertical Section)

GRAPHIC RECORDING OF SPEECH VIBRATIONS

95

from the prism Pri to the open space 00. If, at the same time
voice or other sound waves are passing through the free space 00,
the refraction of R will vary slightly according to the successive
rarefactions and condensations caused by the varying phases of
the sound waves passing through 00, thus shifting the ray or
light-lever into different slightly divergent paths RR and RR\
This divergence is increased by the lenses or mirrors, thus pro-
jecting on PP an enlarged sinusoidal record of the sound waves
passing through 00.

Two modifications of the second prism Pr2 will probably be
found necessary in actual practice. First, it would, if unmodi-
fied in form, tend to neutralize the divergence of the light-lever
R^ effected by the varying air densities in the opening 00, since
the refractive indices of the two prisms Pvi and Pr^ would be
reciprocal to each other for every density of air in the opening
00, while the air density in both sound proof chambers SC and
S'C' remains constant. To avoid] this neutralizing effect, it
will undoubtedly be necessary to concave either the first surface
or both surfaces of the second prism Pr^ at the point or small
area where the light-lever R traverses it, the first center of curv-
ature or concavity lying either at the point where the light-
lever R emerges from the first prism Pri or within the open
space 00. This would in effect introduce a minute concave or
bi-concave lens in the second prism Pn at this point. Again, the
second prism Pr^ may have to be doubled, with a dead air space
between its two parts, in order to preserve the sound proofing of
the second chamber S'C'.

In form A (fig. 4), the arrangement of lenses and focussing
is the same in principle as that of form A of the sonoscope,
shown in figure I. This plan would probably necessitate the
distance RL2 (from the first prism to the fiber lens) to be
relatively very great in order to allow the very slight divergence
of the paths RR and RR' to become sufficient for the lens L2L3
to deal with it. How great this difficulty will prove to be in
practice can be determined by trial.

In form B (fig. 5), two convex glass-tube mirrors Mi and M2
replace the lenses L2L3 and L4 of form A. The focussing follows

96

ROBEKT JAMES KELLOGG

the principle of form B of the sonoscope in figure 2. This form
of the sonograph principle would seem to be more sure of success,
since the tiny tube mirror Mi could deal with and magnify very
small divergences in the paths RR and RR', and probably need
not be as far from 00 as would be necessary for the lens L2 in
form A.

In form C (fig. 6), a simple concave lens is substituted for the
battery of mirrors or lenses of forms A and B. Otherwise it is
the same in principle as form B. The difficulty of length be-
tween the prism Pvi and the lens L2 would probably be much
greater in this form than in form A. Perhaps it could be partly
overcome by using an additonal concave lens between L2 and Fi.

Whether or not the above suggestions prove to be practicable,
the problem of approximating a perfect graphic record of sound
vibrations must fulfil the conditions of eliminating all distortion,
suppression, extraneous addition, reinforcement and muffling.
In the final solution the light lever (or some electrical, magnetic
or x-ray substitute) will probably enter. If a receiver horn and
diaphragm enter in, the form must be so shaped as to have the
widest range of equalized responsiveness to all forms of vibra-
tions, and the diaphragm must be of such form and texture or so
weighted as to avoid all self-vibration and unequal responsive-
ness. Perhaps the outer ear and ear drum of man or other
animals still have suggestions to give us on these lines. If
physically vibrating parts enter in, they must be .of the minute
order of magnitude or vibrative amplitude which allow them to
vibrate fully and freely on the scale of normal sound- vibrations,
and so damped or adjusted as to eliminate muffling, reinforce-
ment and self-vibration. Mechanical construction (if any
remains) must be practically perfect. Probably the final solu-
tion will come along the line of some principle which (like the
sonograph principle suggested above) uses a light-lever whose
initial deflection is effected by refraction as it passes through
free sound-transmitting air.

THE MANIPULATION OF THE TELESCOPIC ALIDADE
IN GEOLOGIC MAPPING

KIRTLEY F. MATHER
INTRODUCTION

The ability to use the telescopic alidade in plane-table mapping
is absolutely indispensable to the geologist engaged in investi-
gating oil and gas resources of any region. Even though he
may be assisted by an ^ instrument man/’ to whom is entrusted
the actual operation of alidade and table, final responsibility
for the accuracy and speed of the work rests with the geologist.
No geologist bent upon applying the principles of geology to
the search for, and production of, petroleum may consider his
training complete until he has had considerable experience using
plane-table and telescopic alidade. Manipulation of the alidade
is sufficiently simple to permit the tyro to grasp quickly its more
obvious details, but at the same time offers opportunities for
ingenuity and resourcefulness sufficiently complex to be worthy
the mettle of the most expert.

It is the purpose of this paper to assemble in convenient form
certain of the more successful methods of manipulating the
alidade, which have been developed during the last few years
by many of the workers with this instrument. It is hoped that
this presentation will be sufficiently simple to enable the be-
ginner to make use of it, and at the same time sufficiently
comprehensive to be a desirable reference work for even the in-
strument man of wide experience. The paper does not include
a description of field methods of mapping, either by traverse or
triangulation; for such a description reference should be made to

97

98

KIKTLEY F. MATHER

the work of Wainwright/ Ransome^^ Wegemann,^ Stebinger^
and others.

The writer is deeply indebted to his comrades of the United
States Geological Survey, especially to K. C. Heald, E. Russell
Lloyd and Eugene Stebinger, for much of the information
assembled here. He is also obligated to the Bausch and Lomb
Optical Company and to W. and L. E. Gurley for illustrations
and tables reproduced from their catalogs and manuals.

DESCRIPTION OF THE ALIDADE

The telescopic alidade consists essentially of a telescope
attached by a transverse axis to a base plate, one edge of which
bears a fixed and approximately parallel relation to the line of
sight, and so supported as to permit the telescope to be elevated
or depressed in a vertical plane. Of the many different models
on the market, that most suited to the needs of the petroleum
geologist is the miniature” or explorer’s” alidade, designed
in 1909 by H. S. Gale of the United States Geological Survey,
some form of which is now produced by each of the leading
makers of surveying instruments. This alidade is illustrated
in figure 1.

The telescope is a metal tube fitted with an object-glass at one
end, an eyepiece at the other, and between the two a reticle
holding cross-hairs. A diagrammatic longitudinal section of the
telescope, showing the paths of light rays passing through it,
forms figure 2.

The object-glass ordinarily comprises a crown lens and a flint
lens so shaped and arranged as to gather the rays of light from
an object and form a small inverted image in the plane of the

1 Wainwright, Plane-table manual. U. S. Coast and GeodeHc Survey, Kept,
for 1905, App. 7, 1906.

2 Ransome, F. L., The Plane-table in detailed geologic mapping. Econ. Geol.
vol. 7, pp. 113-119, 1912.

2 Wegemann, C. H., Plane-table methods as applied to geologic mapping.
Econ. Geol., vol. 7, pp. 621-637, 1912.

^ Stebinger, Eugene, Control for geologic mapping in the absence of a topo-
graphic base map. Econ. Geol., vol. 8, pp. 266-271, 1913.

MANIPULATION OF THE TELESCOPIC ALIDADE

99

cross-hairs. These lenses are contained in a separate smaller
tube which may be slid in or out of the telescope tube by means
of a rack and pinion turned by the focusing screw oii one side of
the telescope in front of the transverse axis. This is necessary
to define sharply the image of distant or near objects at will, or
in other words to provide a means of bringing the objects in the
field of vision into focus.

The eyepiece is similar to a microscope; its purpose is to mag-
nify the cross-hairs and the image thrown by the object-glass.
It may be adjusted to suit the eye of the individual observer by
twisting the knurled ring at the end of the telescope tube. This

Fig. 1. The Gale Alidade with Stebinger Gradienter Drum Attachment
AND Detachable Parallel Rule; Striding Level in Place and
Compass Needle Released, (Photograph from
U. S. Geological Survey.)

shifts the eyepiece toward or away from the cross-hairs. Once
properly adjusted there is no reason for changing the position of
the eyepiece unless the instrument is used by another observer.

If the image formed by the object-glass is not in the same plane with
the cross-hairs, any movement of the eye is likely to cause an appar-
ent movement of the image with respect to the cross-hairs. This is
called 'parallax. The effect is similar to that produced in looking
through a window, where any movement of the eye causes an appar-
ent movement of objects outside. Parallax may render accurate work
impossible. To remedy it the image and the cross-hairs must be
brought into the same plane. Two steps are necessary.

100

KIRTLEY F. MATHER

(1) Point the telescope toward the sky and move the eye-piece in

or out until the cross-hairs are as well defined as possible, i.e., in per-
fect focus

(2) Direct the telescope to the object and focus the object-glass as
usual, keeping the eye on the cross-hairs until the image appears in
sharp focus. Test by moving the eye from side to side, and if neces-
sary move the object-glass slightly until parallax disappears.

The more accurate the work the more care should be used to elimi-
nate parallax, while the higher the power of the telescope the more
difficult it is to do this.^

At the ocular end of the eyepiece is a fixed prism which deflects
the rays of light at right angles to their line of passage through
the telescope and at the same time produces an erect image of
the field. All observations are to be made while the operator is

Fig. 2. Diagrammatic Longitudinal Section of Alidade Telescope;
Paths of Light Rays Indicated by Broken Lines

looking directly down into the eyepiece prism. Some alidades
are fitted with a periscope’’ or tubular roof above the eyepiece
prism in which is housed a lens for the reversal of the image.
When this is wanting, images in the field appear right side up
but reversed from right to left. To keep maximum illumination
of an undistorted field as observed through a roofed prism entails
precision grinding of the highest order of merit; this is obviously
very expensive so that there exists some doubt as to whether it
actually pays to correct the relation of the elements of the field
in this particular.

The magnification of miniature alidades is ordinarily 16 or
20 diameters.

® J. C. Tracy, Plane Surveying. John Wiley and Sons, New York, 1907, pp.
555-6.

MANIPULATION OF THE TELESCOPIC ALIDADE 101

The cross-hair ring, or reticle, is placed so as to be at a prin-
cipal focus of the object-glass as well as at a focus of the eyepiece.
Its position is indicated by four screws or capstans on the outside
•of the telescope tube. The cross-hairs are spider webs, or very
fine platinum wires, almost invisible to the unaided eye. They
are generally four in number and are fastened immovably with
shellac to the brass ring before it is inserted in the telescope.
Two of the hairs cross the center of the ring at right angles to
each other; their purpose primarily is to define the line of sight.
The other two are parallel to one of these and spaced equidis-
tant on either side of it; they are the stadia hairs and are used
primarily for measuring distances. In the Gale design of ali-
dade, none of these hairs are adjustable with respect to each
other, but the whole reticle may be moved by means of the four
screws which hold it in place.

It is very important for purposes of adjustment to understand how
the capstan screws control the movement of the cross-hair ring. . .

. . The holes in the telescope through which the screws pass are not

threaded; on the contrary, they are a little larger than the screws, so
that when the latter are loose the whole ring may be turned slightly
by moving the four capstan heads simultaneously around the outside
of the telescope until one cross-hair is vertical and the other hori-
zontal. When the capstan screws are tight, each screw presses a
curved washer (shown in the photograph) against the outside surface
of the telescope. When one screw is loosened and the opposite screw
tightened, the whole ring Is drawn toward the tightened screw (since
the holes in the shell of the telescope are smooth) until the loose screw
and its washer are brought into contact again with the outside of the
telescope. Notice that before tightening one screw the opposite screw
should be loosened, otherwise the ring cannot move and the screw-
thread may be stripped. By loosening the lower screw and tightening
the upper screw, the whole ring may be drawn upward, or by reversing
the process it may be drawn downward. Likewise by working the side
screws in a similar manner, it may be drawn to one side or the other.
All this may be done without turning the ring, i.e., one hair may be
kept vertical, the other horizontal.®

® J. C. Tracy, loc. cit., p. 550.

102

KIKTLEY F. MATHER

The telescope tube is inserted in a short sleeve at its mid-
length, which forms a part of, the transverse axis by means of
which vertical oscillation is made possible. The telescope is
mounted revolvably between 180-degree stops in this axis--
sleeve and is prevented from turning on its longitudinal axis in
the process of focusing either by a plunger at the under side or
by a clamp ring screwed at one end of the sleeve. At either side
of this axis-sleeve the telescope is surrounded by a ‘Ted metah’
collar, accurately turned to the axis of rotation defined by the
sleeve. These collars are for the support of the striding-level
by means of which the telescope is brought into the plane of the
horizon. The striding-level is removable and when not in use is
held in a corner of the base plate by a binding post. A similar
post is attached to the top of the axis-sleeve and when the strid-
ing-level is put in place- for observations, as in figure 1, it is
snapped down over the shoulder on this post, which merely
prevents it from falling off in case the alidade is tilted and should
not support it in any way. The wyes, trued to the same angle,
at either end of the bubble glass then rest on the metal collars.

The striding-level itself is a glass vial, partially filled with a
non-freezing liquid, ground on the inside to the arc of a circle
with long radius.

The more uniform this curvature is throughout the length of the
tube the more regular will be the motion of the bubble, and the greater
the radius of curvature the greater the sensitiveness of the bubble.
Within reasonable limits’ the more sensitive the bubble the more perfect
the work, though a very sensitive bubble may be too unsteady for
many purposes; on the other hand a sluggish bubble, though it may
give the appearance of steadiness to an instrument, and an impression
that it “keeps’’ its adjustment, is incapable of accurate work

The line tangent to the circular arc of the tube at its middle point,
or a line parallel to this tangent, is called the axis of the huhhle-tuhe.
When this axis is horizontal the bubble will be in the center of the tube.
Should the axis become slightly inclined the bubble will move toward
the higher end of the tube in proportion to the angle made by the axis
with the horizon. The glass tube is usually graduated on top by
marks 0.01 feet (or 2 mm.) apart. The value of a level-bubble is usu-

MANIPULATION OF THE TELESCOPIC ALIDADE 103

*ally expressed by the change which takes place in the inclination of the
axis when the bubble moves over a single space. Thus in a 1 -minute
level for a displacement of one division the inclination changes 1 min-
ute, and in a 20-second level it changes 20 seconds.'^

Ordinarily, the alidades in use by geologists are fitted with
60-second levels, but it is preferable where possible to use
a 20-second level, a change which at low cost adds greatly to the
possible accuracy of the work.

The telescope and axis-sleeve are carried on standards about
two inches high to permit a reasonable vertical swing of the
telescope. The transverse axis projects beyond the bearings
which cap these standards and is gripped on the right by the
vertical clamp. This is tightened or loosened by the knurled
screw, set close to the top of the right hand standard. When
loosened, .the telescope swings freely through an arc of about
45 degrees in the plane at right angles to the transverse axis.
When tightened, the swing of the telescope is limited by the play
of the clamp arm, a downward extension of the clamp proper.
In one style of miniature alidade, this arm is held by a horizontal
spring against the point of a horizontal tangent screw working
through the lower part of the telescope standard. In another
model this arm is expanded, and itself carries the tangent screw
and horizontal spring bearing against a stud fixed to the inside’
surface of the right hand standard. In either, the rotation of
the tangent screw" causes the telescope to be slowly elevated or
depressed. ‘ The screw is therefore spoken of sometimes as the
fine adjustment or micrometer screw. A graduated drum may
be attached to this screw, as in figure 1, which as explained later
may be used in the measurement of distances or the determina-
tion of vertical angles. When thus equipped the tangent screw
is known as the gradienter screw. Or if the special gradienter
drum provided with a celluloid index, as suggested by Eugene
Stebinger, United States Geological Survey, is attached, it is
frequently referred to as the Stebinger drum and screw.

^ J. C. Tracy, loc. cit., p. 544.

104

KIRTLEY F. MATHER

Fixed to the opposite end of the transverse axis and attached
just outside of the left hand standard is a graduated arc, gen-
erally of about 130 degrees duration, by means of which vertical
angles are measured. It is therefore referred to as the vertical
arc. It moves past a shorter arc of similar curvature, which
carries the vernier scale and is adjustable by means of a hori-
zontal screw working through the left hand standard in much
the same way as does the micrometer screw on the right standard.

The base plate is firmly attached to the telescope standards
and is primarily intended to form a straight edge, parallel with
the line of sight through the telescope and maintaining that
fixed relation no matter in what direction the instrument is
pointed. To facilitate the use of the straight edge, the right
side of the plate is beveled and graduated in linear measure; it is
known as the fiducial edge. In the miniature alidades there is
attached to one corner of the base plate a compass box, or de-
clinatoire, housing a compass needle which has a possible oscilla-
tion of about 10 degrees. The compass is not intended for the
reading of angles of departure from magnetic north, but solely
for the designation of the magnetic meridian; therefore the only
markings are the zero points at either end of the needle. The
needle is either of the tubular or the steel bar variety, mounted
generally on a sapphire-tipped pivot, and provided with clamp-
ing device and adjustable balance. The latter must be adjusted
by the user for different latitudes by sliding it along the needle
until it is properly balanced. A declinatoire so constructed as
to make the needle easily accessible is therefore preferable.
There is also fixed to the base plate, generally near the objective
end of the telescope, a hulVs eye level by means of which the plane
table on which the alidade is resting may be quickly brought
into an approximately level attitude.

An extra” attachment which has proved to be a great time-
(and therefore money-) saver is the parallel rule, shown in
figure 1. A brass straight-edge, | inch wide and as long as the
alidade base, carries two brass bars, 1 or IJ inch long, pivoted
near either end, with the pivot centers in a line parallel to the
straight edge. Set in the free end of each short bar is a round

MANIPULATION OF THE TELESCOPIC ALIDADE

105

lug which fits into a circular hole bored in the base plate near
its margin. The centers of these holes are in a line parallel to
the fiducial edge, and the short bars are of equal length. There-
fore the removable straight-edge, when put in place, is parallel
to the fiducial edge and may be shifted close to it or out away
from it without losing its parallelism. In ^Tining-in’^ a distant
station, all the time involved in getting the fiducial edge exactly
on the occupied station point is saved. The line of sight is
mechanically shifted in parallel position to the proper place on
the map. Similar holes may be bored near the left side of the
alidade base, and the same straight-edge attached there for work
close to the left margin of the table, but if that change is made,
the table must be re-oriented because of the probable change in
the relation between the line of sight and the ruler edge. The
parallel rule, when detached, may be conveniently carried in a
pocket sewn across one edge of the alidade case.

The complete instrument weighs about 3 pounds, stands
between 3 and 4 inches in height, and is 10 to 12 inches in length.
It is fitted into a sole-leather case with shoulder strap for carry-
ing in the field.

MANIPULATION OF THE ALIDADE

To determine hearing

In traversing with plane table and alidade, the location of an
unplotted point is determined by its direction and distance from
another point which has previously been plotted on the plane
table sheet. Instead of determining this direction in terms of a
compass or angle reading, to be later drawn on the map in the
office, as is done with transit or theodolite, the determination
and the plotting of the bearing to the distant point are accom-
plished by a single operation. This makes necessary the accu-
rate orientation of the plane table sheet so that the lines drawn
on it will, whenever the plane table is set up for use in the field,
be parallel to the position which they occupied at every preced-
ing set-up.

106

KIRTLEY F. MATHER

Plane table orientation. Orientation of the plane-table sheet
is ordinarily accomplished by means of the magnetic needle
housed in the compass box attached to the base of the alidade.
The fiducial edge of the alidade base is placed along a line ruled
on the plane table sheet, and the needle liberated from its rest
so that it swings freely in its box; the table is then rotated until
the needle points to the north and south marks at either end
of the compass box. Thereafter, whenever the same alidade is
placed on the same side of the same line so that the same edge
of its base coincides with the line, and by rotating the table the
freely vibrating needle is made to come to rest at the same point,
the sheet is in approximately parallel position. The orientation
line ruled on the plane table sheet should extend the full length
of the alidade base, or should consist of two shorter lines, three
or four inches in length, drawn to each extremity of the base.
An arrow should be sketched at the north end of the line or
lines; the compass box is so attached to the alidade that when
the needle comes to rest in the line of the marks at its ends the
line of sight through the telescope leads approximately toward
magnetic north.

Although of course not necessary, it is very desirable and uni-
versally customary so to draw the orientation line that the
sides of the plane-table sheet coincide with the four cardinal
directions. This may be accomplished in several ways, a few of
•which will be mentioned here. In many parts of the country,
the public roads have been accurately surveyed along section
lines; commonly the fences have been similarly placed in a true
north-south or east-west direction; or again, section corners
may be so situated that one corner-post — or a flag placed directly
above it — may be seen from another. If the plane table can be
set up in the line thus determined by road or fence or land net,
the ruler-edge of the alidade should be placed along the margin
of the plane table sheet, or along the line previously drawn to
represent the meridian of the map, and the table rotated until
the line of sight through the telescope falls along the visible line
thus defined. The table locked in that position, the alidade is
moved to the desired part of the sheet and turned until the

MANIPULATION OF THE TELESCOPIC ALIDADE

107

compass needle comes to rest in the line of its indicators. The
orientation line is then ruled along the alidade base. The angle
between that line and the meridian of the map will be deter-
mined by the local magnetic declination as modified by any
divergence which may be present between the line of sight of
the alidade, the fiducial edge of the alidade base, and the line
defined by the compass needle and its indicators. These three
lines need not be parallel; the work will not be affected by diver-
gence between them.

Another method of orienting the table before drawing the
orientation line makes use of a Brunton or other compass, care
being taken to make allowance for the departure of magnetic
from true north, and depends upon previous knowledge of the
magnetic declination in the region.

Or, again, it may be necessary or desirable to draw the orien-
tation line on the plane-table sheet before it is oriented for the
first time. It must then be assumed that the line of sight, the
compass line, and the alidade straight edge are parallel; the error
in orientation thus involved will in most cases be of no conse-
quence. The orientation line is plotted so that the angle be-
tween it and the meridian line is equal to the magnetic declina-
tion.* This angle may be scaled off by means of a protractor, or
if more accurate drafting is desirable, a trigonometric function
may be used. Draw a line 10 inches long in the desired position
of true north; at one end erect a perpendicular such that its
.length in inches is 10 times the tangent of the angle of declina-
tion; connect the other end with the end of the perpendicular
by a line which is the desired orientation line. This is more
accurate than plotting the angle with a protractor which has a
radius of only 3 or 4 inches for in that case any error in plotting
is greatly multiplied when the line is extended to the necessary
length of 12 or 15 inches.

The whole matter of accurate situation of the orientation line
is of slight importance when working upon a plain sheet, but is
of the greatest importance if the work is to be done upon a sheet
on which the land net has been previously plotted, or upon a
base map prepared by other surveyors, as for example an enlarge-

108

KIRTLEY F. MATHER

ment of a portion of a United States Geological Survey topo-
graphic map or a Land Office map.

The use of the magnetic needle for orientation of a plane-
table sheet requires the utmost care. The length of the needle
from its pivot to either end is only 1| to 3 inches, and lines will
frequently be drawn on the map which are much longer than
that. Errors in observing the needle may therefore be multi-
plied during the progress of the work and thus piay become of
more than trivial importance. Careful attention should be paid
to see that the needle is swinging freely; a pocket magnifier
should be used in observing its position with respect to the indi-
cators; observation should be made from directly behind the
instrument so that the observer sights along the needle from
above rather than from the side.

In many instruments the needle is not perfectly straight, or
the two indicators and the needle pivot are not in a straight
line; it is then best to regard only one end of the needle, being
careful always to use that end and not the other. Or, again,
the needle points may be blunt and the indicators of consider-
able width; in that case select a definite relationship of needle
point to marker and adjust the table or alidade so that the
needle always returns to that relationship each time the map is
oriented.

The surveyor must, moreover, be always on guard lest steel
or iron bodies in proximity to the compass box deflect the needle.
Articles about his own person should receive his attention; he
should stand so that his pocket knife is at least a foot from the
needle; a Brunton or other compass must be kept at least 3 feet
distant and must, therefore, be removed from the belt before
attempting to orient the table; the margin of safety for a geo-
logic hammer is a little less than 2 feet, and it may therefore be
left in the belt if carried in the rear and if the surveyor stands
well away from the table in observing the needle; a harmless
appearing, leather-covered metal binocular or monocular case,
if permitted to come within 2 feet of the needle, may lead to the
erroneous conclusion that one is endowed with a superabundance
of personal magnetism. Metallic bodies in the general vicinity

MANIPULATION OF THE TELESCOPIC ALIDADE

109

of the plane table may deflect the needle and introduce grave
errors into the work. The table should never be set up for com-
pass orientation within 10 feet of a wire fence, within 15 feet
of a pump-jack, less than 10 feet away from a pipe-line, buried
or on the surface, closer than 10 feet to a railroad track, or nearer
than 20 feet to an automobile.

The plane-table sheet may also be brought into correct orien-
tation without the use of the compass needle by means of fore-
sight lines. This necessitates the planning of one’s work for
days or even weeks in advance, but should be used in all triangu-
lation work and may be used in orienting the table at any set-up
where for some reason compass orientation is unwise. Assume
that two stations are clearly visible, the one from the other, and
that the table is set up in correct orientation at one, while the
other has not yet been occupied. A line, the fore-sight, is drawn
from the point representing the occupied station in the direction
of the distant objective. It should be drawn the full length of
the alidade base, extending from the plotted point away from the
unplotted as well as toward it, even though the point when
plotted will be only an inch or two away from the occupied
station. Or if preferred, the fore-sight line may be discontinu-
ous, covering the estimated location of the distant station on the
map and including a line an inch or so in length at either end
of the alidade straight edge. When, later, the station to which
the fore-sight line has been drawn is reached in the progress of
the field work, the table should be approximately oriented with
the eye, the alidade base placed along the fore-sight line so that
the telescope points back toward the bid station, and the table
rotated until the distant signal is bisected by the vertical cross
hair of the alidade. The most likely place for error to enter into
this manipulation is in the adjustment of the alidade base to
the ruled fore-sight line; a pocket magnifier should be used in
the placing of the alidade, if the most accurate results are desired.

Still another method of orientation makes use of the Baldwin
Solar Chart. The angle between the apparent position of the
sun and true north is graphically determined by means of this
chart which is so constructed that when turned until the proper

110

KIRTLEY F. MATHER

pivot point on an arrow and the sun- time point’’ on a latitude
arc are on a line parallel to the shadow cast by a plumb-line
upon a level table the arrow points true north. A copy of this
chart and full directions for its use may be found in Topographic
Instructions of the United States Geological Survey, pp. 136 to
141.8

Lining in the station. After the table has been properly
oriented at a station, the location of which has been plotted on
the map, the bearing of any visible object may be drawn directly.
The alidade is moved until the straight edge touches the side of
the needle-hole or pencil dot representing the occupied station
and the vertical cross-hair in the telescope bisects the distant
object, the bearing of which is desired; a line drawn along the
straight edge will then represent the compass-bearing plotted to
position on the map under construction.

The best method to pursue in lining-in a distant station is to
grasp the ends of the alidade base with either hand; shift the
instrument until the line of sight through the telescope falls upon
the desired objective and the fiducial edge rests within an inch or
two of the dot locating the occupied station; then move the
alidade diagonally forward and to the right, keeping the vertical
cross-hair on the distant object, until the ruler edge touches the
proper point. If the alidade is equipped with a parallel-edge
ruler, it is only necessary to place the instrument somewhere
near and to the left of the plotted point in such a position that
the vertical cross-hair cuts the distant station; then push the
parallel straight-edge outward until it touches the proper point.
Some surveyors make it a practice to stick a. needle vertically
into the plane table at the point representing the occupied
station, and to pivot the alidade on the needle when lining-in a
station. This practice is not recommended. Although it is an
easy way for the novice to increase his speed, it involves inaccu-
racies of considerable import. If the needle is inserted far
enough to hold its upright position, it makes a hole several
times as large as necessary; the point becomes a space which on

® Government Printing Office, Washington, D. C., 1918; price 35 cents.

MANIPULATION OF THE TELESCOPIC ALIDADE

111

the customary scales represents an area on the ground, 30 to 60
feet in diameter.

Lines representing bearings should be drawn with the chiseled
edge of a 9-H pencil, being careful always to hold the pencil
at the same angle and to see that the contact of rule and paper
is perfect. By placing the ruler edge in a position tangential to
the tiny circle formed by needle-hole or dot, the line when drawn
should exactly cut the center of the point.’’ If the distant
station is subsequently to be occupied and orientation there is
to be by back-sight, the fore-sight line should be the full length
of the alidade base; if not, the fore-sight line may be short, cover-
ing only the estimated position of the point. It is better not to
draw lines through the dot or needle-hole representing the oc-
cupied station; break the line for a fraction of an inch on either
side.

To measure distance

Distances are directly determined with the telescopic alidade
by means of the stadia hairs and rod. Stadia work depends
upon the hypothesis that the sizes of objects required to produce
an image of fixed size in the telescope are directly proportional
to their distances from the point over which the telescope is set.
This hypothesis is not rigidly correct, but the theoretical error
is small and the practical error negligible. The limits of the
image in the telescope are fixed by the parallel stadia hairs in
the reticle. The object most convenient to use is a graduated
rod. In the alidades commonly used by the geologist, the stadia
hairs are so adjusted that the ratio 'between the distance from
the telescope to the rod and the distance intercepted on the rod
by the upper and lower hairs, when the rod is held at right angles
to the line of sight and to the hairs, is as 100 to 1. If the rod is
100 feet from the instrument, the outer hairs appear to subtend
1 foot upon it; if 1200 feet distant, 12 feet of the rod will appear
between them (see figure 3) . Moreover, the middle cross hair in
the reticle is placed as nearly as possible equidistant from the
outer two. Therefore, the distance subtended on the rod by
the middle hair and either outer hair is 1/200 the distance of the

112

KIRTLEY F. MATHER

rod from the telescope. In some alidades, quarter hairs” are
placed so that they bisect the spaces between the outer and
middle hairs. The ratio for them is, of course, 1: 400; with an
instrument so equipped distances up to 400 times the length of
the rod may be read directly. Sketches showing the relation of
a stadia rod to the field of view at different distances are shown
in figures 4, 5 and 6.

In practice, then, it is necessary only to raise or lower the
telescope until the two stadia hairs appear to rest on the rod,
one intersecting a primary division and the other falling across a
divided foot. Read the intercept and multiply that distance by 100
if the outer hairs were used, by 200, if the middle and one of the

Fig. 3. Diagram Illustrating the Stadia Principle

The diverging lines representing the projection of the stadia hairs form inter-
cepts on the rods proportional in length to their distance from the instrument.

outer hairs were used, or by 400, if the quarter hairs” were read.
Use the most distant hairs the intercept of which may be read,
for otherwise the observational error is multiplied by 2 or 4, as
the case may be. Also place the hairs as near the top of the
rod as possible so as to minimize the error of refraction.

As a matter of fact, the distance in the line of sight to the rod,
thus determined, is not measured from the center of the instru-
ment but from a point in front of the telescope objective at a
distance equal to F, the focal length of the objective. Therefore
the distance from center of alidade to rod is represented by the
formula

D = 100s + F + c,

MANIPULATION OF THE TELESCOPIC ALIDADE

113

where s is the intercept on the rod between the outer hairs, and
c the distance from center of instrument to objective, + c is
practically a constant for a particular alidade, as it varies only

Fig. 4. Stadia Rod in the Field of
View at a Distance of 720 Feet

Fig. 5. Stadia Rod in the Field of
View at a Distance of 1740 Feet

Fig. 6. Stadia Rod in the Field of View at a Distance of 3360 Feet

with the focusing of the instrument. For ordinary purposes it
may be taken as 1 foot, a space so short as to be altogether
negligible in most work undertaken by the geologist.

114

KIRTLEY F. MATHER

Long sights. Occasionally, it is necessary to measure distances
greater than 200 times the rod length with an alidade equipped
only with three stadia hairs. Several different methods of pro-
cedure are available; the choice of the one to use depends upon
the equipment of the instrument, the geographic environment,
and the custom of the individual surveyors. Some of the meth-
ods are in effect schemes to provide a longer rod. Others de-
pend upon trigonometric principles. The method numbered
5 is probably best suited to the more common conditions met
in geologic mapping.

1. Rotate the telescope 90 degrees in its sleeve so that the
stadia hairs are vertical instead of horizontal. Signal rodman
to mark his station with a flag or to select a certain sapling or
post for his station. Place one hair on the station and signal
rodman to move at right angles to the line of sight until the rod,
held vertically, is in line with the other stadia hair. The rodman
will then measure the distance horizontally on the ground from
his second position to his first, using the rod as a measuring
stick, and report the result to the instrument man. Distances
of 4000 to 7000 feet may be determined with a fair degree of
accuracy by this method. It may be used to advantage only
when the two men are able to communicate freely by signals
such as the two-arm semaphore code.

2. Rotate the telescope as before. Signal rodman to hold rod
horizontally and to be prepared to move laterally so that the
base of the rod will occupy the point now occupied by its top.
Intersect base of rod with one stadia hair. Signal rodman to
move over in the desired direction a sufficient number of rod-
lengths so that the other stadia hair will finally intersect the rod.
Read intersection; add the number of feet indicated by the
length of the rod multiplied by the number of moves; multiply
by 100 or 200 depending upon which hairs were used.

3. If instrument is equipped with a Stebinger gradienter drum
attached to the fine adjustment screw, proceed as follows: Place
bottom hair on lowest visible primary division of the rod; read
and record Stebinger. Turn Stebinger drum until middle hair
rests on the top of the rod; read and record Stebinger. Take

MANIPULATION OF THE TELESCOPIC ALIDADE

115

the difference of the two Stebinger readings; turn an equal
number of divisions in the direction which brings the middle
hair down onto the rod; observe the number, of feet between
the top of the rod and the intersection of the middle hair. Add
this to the length of the rod which was above the bottom hair at
the first reading; the sum multiplied by 200 is the horizontal
distance. For example:^ 12 feet of the rod are entirely visible
and the middle hair is well above the rod when the bottom hair
rests 12 feet below its top. In that position the Stebinger drum
reads 24. Turn down until middle hair touches the top of the
rod; Stebinger reading is now 60. The difference between the
two readings is 36. Turn down 36 divisions more, to 96. The
middle hair now intersects the rod 3.4 feet below its top. The
horizontal distance is 200 X (12 + 3.4) or 3080 feet.

4. If instrument is equipped as in 3 and there is at hand a
table, previously prepared for this particular instrument, show-
ing Stebinger factors,^® i.e., the differences in elevation at the
unit distance of 100 feet corresponding to the vertical swing of
the telescope denoted in divisions of the Stebinger drum, pro-
ceed as follows: Place one hair on the top of the rod; read and
record Stebinger. Turn down until that hair cuts the lowest
visible primary division of the rod; read and record Stebinger.
Take the difference of the two readings. Repeat for each of the
other two hairs. The three results should check. Select from
the table the Stebinger factor corresponding to that number of
divisions. Note the number of feet passed over on the rod;
multiply it by 100 and divide by the factor. The result is the
horizontal distance. For example: 13 -feet of the rod are visible.
With the middle hair resting on the top of the rod, the Stebinger
reading is 62. When the middle hair is turned down to the
primary division 13 feet lower, the reading is 106. Difference of
the two readings is 44; corresponding factor is 0.4111; horizontal
distance is 1300 0.4111 = 3160 feet.

^ This, and the following examples apply only to those instruments in which a
clock-wise rotation of the Stebinger drum depresses the objective end of the
telescope.

The preparation of such a table and the mathematical principles on which
it is based are discussed in subsequent pages of this paper.

116

KIETLEY F. MATHER

This method is frequently employed by ingenious surveyors
to good advantage in determining distances without the use of
the stadia rod. Any two points, one above the other, at known
distances apart suffice; two flags at a measured interval, the
crown plate and girths (commonly eight feet apart) of a stand-
ard derrick, the eaves and lower copings of a church tower, are
listed merely as suggestions. If the location of such a target is
plotted, the surveyor may ‘‘shoot himself in,” with a fair degree
of accuracy, at any point from which it is visible.

5. If alidade is equipped as in 3, an alternative method which
may be used is as follows: Place middle cross hair on top of
rod; read and record Stebinger, denoting the record as A. Turn
down until middle hair intersects the lowest visible primary
division; read and record Stebinger (record B), Turn down
until top hair rests on top of rod; read and record Stebinger
(record C). Compute distance by the formula

B

200 r

C-A

B-A

in which D represents the distance, r the length of the rod above
lowest visible primary division, and A, B, and C, respectively
the three readings of the Stebinger drum. For example: a
13-foot rod is entirely visible. The middle hair on top of rod
gives a Stebinger reading of 31; middle hair on bottom of rod
gives a reading of 54; top hair on top of rod gives a reading of 78.

Distance = 200 x 13 x

78 - 31
54 - 31

5300 feet.

The formula may be more easily recalled if one has grasped
the principle upon which it is based. The Stebinger difference,
C-A, is theoretically a constant, the measure of the angle between
the rays converging from the top and middle cross hairs to the
focus of the telescope. If the rod at the distant point were of
sufficient length, the intercept subtended by this angle could be
read and, multiplied by 200, would give the distance to the rod.
That is, if i be taken to mean the length in feet of that hypothet-
ical intercept,

MANIPULATION OF THE TELESCOPIC ALIDADE

117

i = D 200.

But

i : r :: C-A : B-A,

for the Stebinger difference C-A is. the measure of the angle
defined by the chord i and B-A is the measure of the angle de-
fined by the length of the rod at the same distance. Therefore,

(D 200) : r :: C-A : B-A,
or

D- 200r^.

Fig. 7. Diagram Illustrating the Stadia Principle applied to Inclined Sights

Inclined sights. This discussion of the measurement of dis-
tances with the stadia has been based on the assumption that
the rod is always held perpendicular to the line of sight and that
the desired distance is to be measured along that line. As a
matter of fact, most of the sights in stadia work are taken not on
a level, but on a slope or inclination, as suggested in the diagram,
figure 7. Consequently if the rod is held vertically, the stadia
intercept is somewhat more than it would be when held per-
pendicular to the line of sight, and an element of error is intro-

118

KIRTLEY F. MATHER

duced. This error amounts to 1 per cent of the distance for a
gradient of 8 degrees, 2 per cent for 11 degrees, and 3 per cent for
14 degrees. It may obviously be corrected by tilting the rod so
that it is perpendicular to the central visual ray from the tele-
scope. This may be acconofplished by attaching a short pointer
to the rod at right angles to its face and aiming this pointer at
the instrument when the sight is taken. It is, however, difficult
to hold the rod steadily in this position and this corrects only
one of the two discrepancies. It is therefore customary to hold
the rod vertical no matter what the angle of slope may be and
make the correction in the tables for distance and elevation.
The second discrepancy is due to the fact that the distance to be
plotted is the horizontal distance from telescope to rod, not the
inclined distance. So far as plotting is concerned, this dis-
crepancy, and therefore the angle of inclination, must be fairly
large before it need be taken into account; how large depends
upon the scale of the map, but for most work it may be neglected
for all angles of less than 3 degrees. With an angle of 5| degrees
this discrepancy amounts to about 1 per cent, which for a dis-
tance of 1000 feet is little more than the diameter of a needle
hole on a scale of 1: 31,250.

The stadia tables ordinarily used include the correction for
horizontal distance of inclined sights. In practice, such tables
should be consulted before plotting distances determined by
sights which depart more than 3 degrees from the horizontal.
Reference to the accompanying diagram, figure 7, will make
clear the mathematical formula upon which the correction tables
are based. In the diagram, AB represents the intercept on the
rod held vertically, CD the intercept on the rod held perpen-
dicular to the line of sight from G, GE, the distance from table
to rod in the line of sight, and GF the horizontal distance from
set-up to station. The angle of inclination of sight and the equal
angle between the two positions of the rod are indicated by m.
By trigonometry,

CD = AB cos m

and .

GF = GE cos m.

MANIPULATION OF THE TELESCOPIC ALIDADE

119

But

GE = 100 CD = 100 AB cos m;
therefore^ by substitution,

GF = 100 AB cos2 m,

by means of which the horizontal distance may be computed
from the rod intercept and the angle of inclination.

The correction to be applied to the observed distance on
inclined sights may be determined without reference to tables or
formulae by means of the Beaman stadia arc (see fig. 11) an
attachment for the mechanical solution of the stadia problem,
which will be described in greater detail in a subsequent para-
graph. The arc carries two scales, a multiple scale and a reduc-
tion scale, having coincident zero points marked 50 and 0, re-
spectively. The reduction scale is, of the two, the more distant
from the adjustable index and gives percentages of correction
that may be used to reduce observed stadia distances to hori-
zontal. The adjustable index should be set opposite the zero
of the reduction scale when the telescope is level. To get the
necessary correction, simply read the same scale with the line
of sight cutting the distant station. Reading to the nearest per
cent is usually sufficient. For example: the reduction scale
reads 3 with an observed rod intercept of 16.2; then 3 per cent
of 1620 = 48.6; 1620 — 48.6 = 1571.4 = corrected horizontal
distance.

Location of stations. The distance thus determined by stadia
is scaled off on the line ruled in the direction of the rod station
from the point representing the occupied station. The proper
method is to place the fractional scale division on the plotted
point and prick the new location with the needle, or mark it
with a well sharpened pencil, at the even division at the end of
the scale. This operation should be performed with the greatest
care and preferably with the assistance of a pocket magnifier;
more closure errors are to be attributed to careless plotting than
to any other cause. If a needle is used, do not try to puncture a
hole clear through the paper; push the needle point just far

120

KIKTLEY F. MATHER

enough into the paper to make a permanent indentation, being
careful to hold the needle vertically.

Accuracy of the stadia method. The telescopic alidade and
stadia rod are to be looked upon as instruments of precision;
distances are not estimated, but accurately determined in well-
conducted stadia work. Although essentially intended to secure
rapidity rather than accuracy, the stadia method employed with
due care to eliminate the chief sources of error is capable of
attaining a high degree of accuracy.

Perhaps some of the most interesting results obtained with stadia?
as showing its precision, were those obtained by Mr. J. L. Van Ornum
in taking topography on the international survey of the Mexican
Boundary. The whole of the boundary line was .measured with the
stadia, and a large portion of it by the chain, and always tied in by a
system of accurate primary triangulation. Corresponding distances
were found by stadia and chain and compared with the known dis-
tances as obtained by triangulation, with the following results:

Of five different stretches measured by the three methods, the total
distance shown by triangulation was 99,110 meters, by stadia 99,025

meters, by corrected chain 99,041 meters Other sections of

the line were measured by stadia and triangulation, but not by chain.
In all there were measured 182.5 miles by stadia w;hich were triangu-
lated and in which the total difference in length was plus 50 meters, or
1 in 5837. It tnay be noted that the chained distance was marked
corrected chain, because in six measurements of the chained distance,
dropping or omission of chain-lengths occurred which were detected
in every instance by the stadia.

To determine differences in elevation

Methods of determining differences in elevation by means of
the telescopic alidade are even more numerous than those in
vogue for measuring distances. The good instrument man will
know several different methods and select the one best suited to
the particular sight, depending upon the accuracy required, the
inclination of the sight, the equipment of the instrument, and

H. M. Wilson, Topographic Surveying. John Wiley and Sons, New York,
1910, pp. 241-2.

MANIPULATION OF THE TELESCOPIC ALIDADE

121

the necessity for speed. The more commonly used methods will
be described in the order of their simplicity.

1. Direct readings on the rod. Occasionally the difference in
elevation between plane table and rod is so slight that with level
telescope the middle cross hair intersects the rod. The vertical
distance from the bottom of the rod, or from any other selected
point on it, to the point of intersection may be read directly
from the graduations on the rod’s face. Care must be exercised
to prevent the confusion of the top and bottom stadia hairs with
the middle cross hair. It is the visual ray projected by the
middle hair that is parallel to the striding level and therefore is
horizontal when the level bubble is centered.

But, suppose that when the instrument is level, the middle
hair falls above or below the rod while one of the other hori-
zontal hairs cuts the rod. In practice it is customary first to
read the rod intercept for distance and second to determine the
vertical difference between instrument and rod; therefore, the
operator has just measured the vertical distance between the
visual rays projected by the cross hairs at the position occupied
•by the rod. The bottom hair, in figure 8, for example, cuts the
rod at a point, the distance of which below the point where the
middle hair would intersect the rod, were the rod long enough,
has just been determined. Similarly, the top hair in figure 9
intersects the rod at a known distance above the middle hair.
Hence, if any of the three hairs rests on the rod when the tele-
scope is level, the vertical difference between instrument and rod
may be measured directly.

Examples are illustrated in figures 8 and 9. In the former,
the horizontal distance has been read as 1050 feet and with level
telescope the bottom hair intersects the rod 9.6 feet above its
base, which is therefore 14.85 feet below the elevation of the
instrument. In the latter, the horizontal distance has been
determined as 1960 feet and with level telescope the top hair
intersects the rodT.8 feet above its base, which is therefore 8
feet above the alidade.

In practice it is only necessary to record the horizontal dis-
tance and the rod intersection, noting which hair intersects the

122

KIRTLEY F. MATHER

rod, with level sight. The vertical distance can be determined
later by addition or subtraction.

2. The step method.^^ The same principle may be extended to
cover a much larger range of circumstances. Suppose the rod is
so far below the elevation of the alidade that with level sight all
three hairs project rays slightly above the top of the rod. Note
where the middle hair intersects any fixed object in the field — a
point on a nearby tree, or a certain rock on the distant hill-side.
Turn down the instrument until the top hair intersects the

Fig. 8. Stadia Rod in Field of View
WITH Level Telescope at Dis-
tance OF 1050 Feet

The base of the 13 foot rod is 14.8 feet
below the elevation of the alidade.

Fig. 9. Stadia Rod in Field of View
WITH Level Telescope at Dis-
tance OF 1960 Feet

The base of the rod is 8.0 feet above
the elevation of the alidade.

now appears to be 1/100 the

same object. The bottom hair
horizontal distance, previously determined by the stadia inter-
cept on the rod, below the point where the middle hair had for-
merly been. If the bottom hair now cuts the rod, read its inter-

Douglas, E. M., The stadia and stadia surveying. ‘Engineering News, vol.
63, pp. 483-484, 1910. Meyer, A. F., The ‘‘interval” method of determining
elevations in stadia surveys. Engineering News, vol. 64, pp. 231-232, 1910.
Edgerton, H. H., Jr., Modern methods of economical railway location.
Engineering and Contracting, vol. 41, pp. 229-232, 1914.

MANIPULATION OF THE TELESCOPIC ALIDADE

123 ‘

section and add that figure to 1/100 the horizontal distance to
get the V. D. (vertical difference in elevation), which in this
case, would be negative. If the bottom hair is still above the
rod, note where it in turn intersects some fixed object in the
field of vision and turn down the instrument until the top hair
occupies its position. The bottom hair now appears to be 2/100
the horizontal distance below the point intersected by the middle
hair with level sight. The process may be repeated, noting how
many steps’’ are used, until the bottom hair finally intersects
the rod.

Obviously, the same method may be utilized for determining
elevations of stations above the instrument by stepping up”
from the level sight until the top hair cuts the rod. Figure 10
illustrates the method. In recording observations it is only
necessary to note the observed distance, the number of steps, the
final rod intersection, and the sign of the V. D., plus for stations
above and minus for stations below the instrument elevation.
For example, a sight to a station 1760 feet distant, recorded as
“ +4 (steps) — 3.5”, indicates that the base of the rod is (4 X
17.6) — 3.5, or 66.9 feet above the instrument. Or, a sight of
1320 feet with the V. D. recorded ^‘—3 (steps) — 12.9” indicates
that the base of the rod is — (3 X 13.2) — 12.9, or — 52.5 feet
in relation to the altitude of the telescope.

Attention should be directed again to the fact that the first
^^step” is in reality only a “half step” for by it one of the outer
hairs is moved to the position occupied by the middle hair,
whereas, each step, after the first, involves the movement of
one outer hair to the position occupied by the other outer hair.
This is compensated by the fact that the reading of the rod
intersection after the final “step” is a reading of the position of
an outer hair, not that of the middle hair. This makes the
final “step” really a “step and a half” for the hair, the inter-
section of which is read, is a^half intercept above or below the
middle hair.

The “step” method when used by an experienced instrument
man is very fast and fairly accurate. It is not, however, suffi-
ciently accurate for important work, as there is wide margin of

124

KIRTLEY F. MATHER

error involved in the placing of one hair in the position previ-
ously occupied by another. Moreover, there is no simple way
of correcting the error resulting from the inclination of sight to
the rod when the intercept is read. The ^^step’’ method should

A

ii>

IS

V

E

D

C

B

A

Fig. 10. The Step Method

Circle A encloses the field of view as observed through the level telescope.
Circle B is the field after the telescope has been raised so that the bottom cross
hair occupies the position occupied in A bj^ the middle hair. C and D represent
the second and third steps, in each of which the bottom cross hair rests in the
position previously occupied by the top hair. In D, the third step, the top hair
cuts the rod 0.5 feet above its base. The rod intercept, 16 feet, is indicated
in E. The base of the rod is therefore 3 X 16 — 0.5 = 47.5 feet above the
instrument.

never be used when more than 6 steps are necessary, nor to
determine the elevation of a turning-point or set-up. It is well
fitted to serve as a check upon the more accurate methods next
described, when there is need for especial care to guard against

error.

MANIPULATION OF THE TELESCOPIC ALIDADE

125

3. Vertical arc determinations. Other and more accurate
methods of measuring the difference in elevation between two
stations depend upon the determination of the vertical angle
between the line of sight from one station to the other and the
line of sight through the level telescope. The methods differ
only in respect to the reading or computation of that angle; all
are based upon the same mathematical principle. In figure 7,
FE represents the vertical distance from the intersection of the
middle hair on the rod, AB, to the level of the instrument at G.
CD is drawn perpendicular to the line of sight, GE, the angle of
inclination of which is represented by m.

By trigonometry '

CD = AB cos m

and

FE = GE sin m.

But

therefore

GE = 100 CD = 100 AB cos m;

FE = 100 AB sin m cos m = 100 AB X J sin 2m,

the formula upon which stadia tables are based.

The angle of inclination of the line of sight to the target may
be read in degrees and minutes by means of the vertical arc.
With loosened clamp the telescope is raised or lowered until the
middle cross-hair rests near the selected target. The clamp is
tightened and by means of the tangent screw the middle hair is
accurately placed on the target. The point on the vertical arc
opposite the zero of the vernier is read to the nearest minute and
recorded. The telescope is then leveled, first loosening the
clamp if* desired, and the bubble in the striding level centered
by adjustment of the tangent screw. The point on the vertical
arc now opposite the vernier zero is read and recorded; the dif-
ference between the two readings is the desired vertical angle.

The graduations of the vertical arc differ on alidades of dif-
ferent manufacture, but one of the common graduations is indi-
cated in figure 11 by the markings on the left half of the arc.
The main scale of the arc is divided into degrees and half degrees.

126

KIKTLEY F. MATHER

By means of the vernier it may be read in minutes. The vernier
is an auxiliary scale qn which there are 30 graduations occupying
a space equal to that of 29 graduations on the main scale. That
is, each division on the vernier is just one-thirtieth smaller than
a division on the main scale. If, therefore, the zero line of the
vernier is directly opposite a line on the main scale, no other
line on the vernier scale will coincide with a division of the main
scale except the thirtieth. If, then, the arc be moved one minute
( = one-thirtieth of one division) to the right, the first line on the
left of the vernier zero will coincide with a line on the main scale;
if the arc be moved 15 minutes to the right, the fifteenth line
on the left of the vernier zero will coincide with a line on the
main scale, etc. On this principle the arc graduated only to
half degrees may be read in minutes. On an arc graduated
from right to left, read the highest division to the right of the
vernier zero line; this will be either an even degree or a degree
plus 30 minutes. Observe which line on the vernier coincides
with a line on the main scale; add its value in minutes to the
reading of the main scale. For example: the vernier zero is
between the 24° 30' and 25° graduations of the main scale; line
16 on the vernier coincides with a division of the main scale; the
arc reading is therefore 24° 46'.

A vertical angle of 1 minute subtends a chord of 0.3 feet at
a distance of 1000 feet; hence it is imperative that no mistake be
piade in selecting the vernier division which conicides most
closely with a line of the main scale. Most surveyors make it a
practice always to use a pocket magnifier in reading the vernier.
It is also easier to detect offsets of the main scale and vernier
division lines if one looks obliquely along the lines at an angle of
30 or 40 degrees with the face of the scale than it is when observ-
ing the vernier face from a direction perpendicular to it. The
most common of the serious errors which may involve the vernier
reading is to overlook the | degree division of the main scale and
count it as an even degree; guard against that blunder by com-
puting the position of the vernier zero twice for each angle.

Most alidades are equipped with adjustable vernier and with
main scale so graduated that the vertical arc may be set to read

MANIPULATION OF THE TELESCOPIC ALIDADE

127

30° 00' when the telescope is level. Among topographers it is
customary, in reading vertical angles, first to level the instru-
ment and set the vernier at 30° 00', and second to turn the tele-
scope down or up for the reading on the distant object. It is
then necessary to record only one angle reading — that made
after the cross-hair is set on the target; a reading less than 30°
00' indicates an angle of elevation, one greater than 30° 00' an
angle of depression if the arc is graduated from right to left.
This procedure is not recommended for petroleum geologists,
however, because of inherent differences in the work of these
two classes of alidade-users. In the topographer’s party the
lowest-paid man is ordinarily holding the rod on the station to
which the sight is being taken. It is of little consequence
whether he remains there four minutes or two. When he is
moving on to the next station the topographer’s time is occupied
with sketching contours; he has no idle moments. In the petro-
leum geologist’s party, the reverse is the case. The highest-
paid man ordinarily holds the rod; the amount of work the party
can do in a day is in inverse ratio to the length of time he is
kept idle while the instrument man makes observations. While
he is moving on to the next station, the selection of which will
ordinarily require 10 to 20 minutes, the instrument man has
nothing to do except compute his results — a task which if neces-
sary may be done later in ^The office.” Moreover, the geol-
ogist’s plane table is customarily lighter and smaller than that
used by the topographer; it is seldom possible to get it in a
precisely level attitude. Therefore it would be necessary to
level the telescope and set the vernier after the geologist has
occupied the fore sight station and while he is waiting for the
observations to be made. The procedure of the instrument man
should be planned explicitly to minimize the length of time the
rodman is kept at a station. Just as much of instrument work
as possible should be done after the rodman has been waved
on.” With this in mind, the instrument man signals the rod-
man as soon as the cross hair is set on the selected mark on the
rod; after the rodman has departed he reads and records the
vernier, levels the telescope, reads and records the new position

128

KIRTLEY F. MATHER

of the vernier, wherever it happens to be, and determines the
vertical angle by subtraction. He is then under no pressure of
haste in reading the vertical arc and in centering the level bubble.
To increased speed of geologic work is added thereby greater
accuracy in instrumental observations. The record, then, in-
cludes two angle readings, one on the target and one with level
telescope; the sign of the angle, plus for stations above and minus
for those below the altitude of the table; and the observed inter-

Fig. 11. Explorers’ Alidade, with Vertical Arc Combined with Beaman

Stadia Arc

Courtesy of W. and L. E. Gurley, Troy, N. Y.

cept on the rod. From these data the vertical distance may be
computed at leisure.

4. Beaman stadia arc. The reading of vertical angles may be
avoided by the use of the Beaman stadia arc, illustrated in
figure 11. This is a specially graduated vertical arc which may
be attached to the vertical limb of a transit or telescopic alidade.
It carries two scales, of which the one nearer the adjustable
index is known as the multiple scale because it indicates mul-

MANIPULATION OF THE TELESCOPIC ALIDADE

129

tiples for obtaining differences in elevation. The zero point of
this scale is marked 50 and its divisions are so spaced as to be
proportional to one-half the sine of twice the angle through
which the telescope moves.

To determine differences in elevation read the distance subtended
on rod and express in feet (for example, 8.7 = 870 feet). Clamp
telescope and level. Set index exactly at 50, by means of the tangent
screw back of arc, and do not touch this tangent screw again.

Then, by means of the customary clamp and tangent movement,
raise or lower telescope until there is brought exactly opposite the
index such a graduation on the multiple scale as will throw the middle
stadia wire somewhere on the rod, it does not matter where. The arc
reading, minus 50, multiplied by the observed stadia distance gives
the difference in elevation between the instrument and a known point
on the rod — that is, the height on rod indicated by middle wire. Set-
tings of both index and arc should be made carefully under reading
glass.

Example: Suppose observed stadia distance is 6.3 (630 feet) and that
telescope is so inclined that multiple scale reads 58, at which exact
setting the middle wire on rod reads 7.2 (7.2 feet above base of rod)
then multiple is 58 — 50 = -h 8, and computation for a fore sight
would be ‘

6.3

X8

+50.4

-7.2

+43.2 feet = base of rod aboye H. I.

If middle wire were set on H. I. or top or other fixed point on rod
and the arc were read by estimation (for example, 54.2) to obtain a
multiple, the result would be approximate only; therefore this method
is not to be used with this attachment.

If the half-wire interval is read and this reading is then doubled to
get the stadia distance, it occasionally happens that no even multiple
arc setting which will throw middle wire on rod can be found. In this
case make arc setting that will throw the lower wire anywhere on rod ;
the middle wire will then be somewhere above the top of the rod.
Then take multiple as read on arc, but compute position of middle

130

KIRTLEY F. MATHER

wire above base of rod by adding one-half the expressed stadia distance
(in feet subtended) to the reading of the lower wire.

Example: If the half wires subtend 7.2 on rod, the distance would
be 7.2 X 2 = 14.4 (1440 feet). If the lower wire cuts the rod 8.7 feet
above its base, the computed middle wire reading would be 8.7 4- 7.2
= 15.9 feet above base of rod. Then compute as before.

The advantages of the stadia arc are readily apparent. The
use of stadia tables, slide rules, or diagrams is entirely obviated,
nor is there any vernier to be read. The accuracy of results is
identical with that obtained from formula or table computa-
tions; in fact differences in elevation may be read more closely
than is possible where vertical angles are determined only to the
nearest minute. Moreover the simplicity of the process elim-
inates many of the chances of error which are incidental to the
use of other methods and gives final results in minimum time.
The use of the arc is, however, limited to sights which involve
the reading of the stadia rod, and for most shots’^ it holds the
rodmah on the station longer than is necessary with certain other
methods.

' If it is desired to use the Beaman stadia arc principle with
an instrument not regularly equipped for such work,, the ordi-
nary vernier arc may be used by reference to the following table,
which is also of use in checking the action of the Beaman scale.
It is computed from the formula: — vertical distance = i sine
of twice the vertical angle, and gives values by which the Bea-
man intervals can be translated into angular valuations and
vice versa.

S. Stebinger gradienter drum. The accuracy of a sensitive
bubble vial in the striding level is greater than that implied by
the reading of the vertical angle only to even minutes. The
fine adjustment tangent screw is so threaded^^ that a complete

Topographic Instructions of the U. S. Geol. Survey, Washington, Gov.
Printing Office, 1918, pp. 131-2.

The intention of the makers commonly is to calculate the pitch of the screw
and the length of the clamp arm so that one complete revolution of the screw
head moves the line of sight 1 foot vertically at a horizontal distance of 100 feet,
but this ratio may not be safely depended upon except as a broad approximation.

MANIPULATION OF THE TELESCOPIC ALIDADE

131

Table showing angular values of Beaman intervals'^

NUMBER OP

ANGLE

DIFFERENCE IN

NUMBER OP

ANGLE

DIFFERENCE IN

INTERVAL

o

'

INTERVAL

'

MINUTES

0

00.00

34.38

36.16

1

0

34.38

34.39

16

9

19.89

36.42

2

1

08.77

34.42

17

9

56.31

36.70

3

1

43.19

34.47

18

10

33.01

37.00

4

2

17.66

34.52

19

11

10.01

37.32

5

2

52.18

34.59

20

11

47.33

37.71

6

3

26.76

34.68

21

12

25.04

38.08

7

4

01.44

34.77

22

13

03.12

38.49

8

4

36.21

34.88

23

13

41.61

38.95

9

5

11.09

35.02

24

14

20.56

39.44

10

5

46.11

35.16

%

15

00. OQ

^39.97

11

6

21.27

35.33

26

15

39.97

40.54

12

6

56.60

35.50

27

16

20.51

41.16

13

7

32.10

35.71

28

17

01.67

41.85

14

8

07.81

35.92

29

17

43.52

42.58

15

8

43.73

30

18

26.10

*Reproduced by permission from Metro Manual, Bausch and Lomb Optical
Co., Rochester, N. Y., 1915, p. 114.

revolution deflects the telescope about 34 minutes, so that if the
unit of measurement be 1/500 a revolution of that screw, the
accuracy of reading vertical angles is greatly increased. This
is especially important in determining the difference in elevation
of a station two to eight miles distant as is frequently done in
triangulation work. The Stebinger gradienter drum surround-

132

KIRTLEY F. MATHER

ing the tangent screw is graduated into 100 divisions, so broadly
spaced that the drum may be read accurately by estimation to
0.2 division, and so quickly legible that there is marked saving
of time and increased safeguard against error in observation
when it is used in preference to the vertical arc. It is in reality
simply another method of reading the vertical angle, denoting
the angle by an arbitrary unit instead of by degrees and minutes.
The value of that unit in length of chord at known distances
may be expressed in tables similar to those provided for com-
putation from vertical arc readings.

In most instruments a clock-wise rotation of the Stebinger
drum depresses the objective end of the telescope by pressing
against a little stud fixed to the inside surface of the right hand
standard. A counter-clock-wise rotation permits a spiral spring
to expand against the opposite side of the stud and thus to raise
the objective end of the telescope. Experience indicates that it
is unsafe to trust the spring to act with uniform regularity and
smoothness. It is therefore necessary in using the Stebinger
method always to read vertical distances in one direction —
usually downwardly — the direction in which the telescope is
moved by clock-wise rotation of the drum. If the station is
higher than the telescope, the first reading is taken with the
horizontal cross-hair cutting the target; the telescope is then
turned down to the level position for the second reading. If
the station is lower than the instrument, the telescope is leveled
for the first reading of the Stebinger drum and then turned down
till the cross-hair cuts the target for the second reading.

The fine adjustment screw to which the Stebinger drum is
attached is a tangent screw; that is, its motion is tangential to
the arc described by the arm of the clamp of the telescope axis.
Therefore, a revolution of the screw, when it is near one of its
limits of motion will elevate or depress the telescope through an
arc slightly different from that resulting from an equal turn of
the screw when it is midway between its limits. Therefore it is

In some instruments the screw is fixed to the telescope stanclaid and the
stud is attached to the arm of the clamp of the telescope axis; when so attached
the direction of movement to be used in reading the gradienter is upward.

MANIPULATION OF THE TELESCOPIC ALIDADE

133

necessary always to begin an angle reading with the tangent
screw in approximately the same position as that from which
the determination of the Stebinger factors was made. This
position, generally about a quarter turn of the screw after it
first ^ Takes hold,” should be indicated by a mark on the cellu-
loid or steel index. After each reading the tangent screw should
be withdrawn to that position, ready for the next reading.

In practice, then, the first reading is made with the Stebinger
drum somewhere near the predetermined starting point and
with the cross-hair on the distant object, if it is higher than the
instrument or with the telescope level if the sight is a ^^down
shot.” The reading, a figure between 0 and 100, is recorded in
the proper column of the note book. The telescope is then
turned down by means of the tangent screw to position for the
second reading. As the Stebinger drum revolves the total
number of revolutions should be counted. The count may be
verified by the graduations on the index bar if present and is
set down at the left of the two digits which indicate the Stebinger
division, beneath the index. For instance, after completing 8
revolutions, the Stebinger drum is brought to rest at 67; the
second reading is therefore recorded in the appropriate column
as 867. With an alidade which “reads down,” as is the more
common arrangement, the smaller of the two Stebinger readings
will be in the Sight” column if the target is higher than the
instrument, and in the Level” column if lower than the instru-
ment. The difference of the two readings expresses the size of
the vertical angle in terms of Stebinger divisions. From the
Stebinger tables prepared for the individual instrument the
corresponding Stebinger factor” is selected. This factor multi-
plied by the apparent distance gives the difference of elevation
of target and plane table.

The preparation of the Stebinger tables is essentially the
determination of the value of Stebinger units in terms of circular
measure. Withdraw the micrometer screw to the position from
which determinations of vertical angles will be started. Set the
drum on an even division and read the vertical arc; turn the
drum through 100 divisions and read the arc again. Turn

134

KIRTLEY F. MATHER

through 200, 300, etc., divisions, reading the arc at each hun-
dred until the screw has reached the farther limit of its play.
Usually 9 or 10 hundred divisions will suffice. Repeat the opera-
tion at least five times and take the average value in minutes
for each hundred divisions. Determine the corresponding dif-
ference in elevation for each of these angles by interpolation of
the regular stadia tables or from a table of natural sines by the
formula: Difference of elevation = J sine of twice the angle.
The first value thus determined divided by 100 is the difference
in elevation corresponding to each Stebinger division between
0 and 100. The second value minus the first and divided by
100 is the difference in elevation corresponding to each Stebinger
division between 100 and 200. The third minus the second and
divided by 100 is the value for Stebinger divisions between 200
and 300, etc. Carry the quotients in each case to the fifth
decimal. With an adding machine set at the difference in
elevation for one division between 0 and 100, print 100 addi-
tions for the factors corresponding to the first 100 Stebinger
divisions. Then with the machine set at the difference in eleva-
tion per division between 100 and 200, print 100 additions for
the factors corresponding to the second 100 Stebinger divisions.
Complete the table in this manner, changing the addition figure
after each 100 additions. Number the divisions, strike out the
extra decimals beyond the third for the first 50 divisions and
beyond the second thereafter, and typewrite into tabular form
in parallel columns; the number of divisions in one column, the
corresponding factors in another. Brief tables for correction
because of curvature and refraction as well as for conversion of
observed to horizontal distances should be added at the margin.
The whole, if properly planned, will occupy a sheet about 5x7
inches in size when photographed to one-half reduction for field
use.

A slight modification^® of the above method will give a still
more accurate series of factors. Read the vertical arc at each
50th division of the Stebinger drum instead of each 100th; deter-

Suggested by K. C. Heald of the U. S. Geological Survey.

MANIPULATION OF THE TELESCOPIC ALIDADE

135

mine the corresponding difference in elevation for each Stebinger
unit as before; with the factors thus obtained plot a curve using
the numbers of divisions as the abscissas and the values as the
ordinates. From this curve the point will be readily apparent
at which the micrometer screw begins to work with reasonable
uniformity; begin constructing the table to be used at that
point. From the curve determine the points where the factors
for two successive divisions differ by 0.00005 and compute the
factors for the number of divisions represented by each of these
points; interpolate between the values thus obtained to complete
the table.

The table of Stebinger factors should be checked every few
weeks by comparing a half dozen Stebinger readings, made at
haphazard intervals well distributed throughout the range of
the micrometer screw, with the corresponding readings of the
vertical arc. The Stebinger factor should be identical, on the
average, with the vertical distance corresponding to the arc
reading.

In reading the Stebinger drum the observation should be made
from directly above the celluloid or steel index so as to project
the index line vertically downward to the drum. Ordinarily, a
reading to the nearest Stebinger division is sufficiently close, but
for low angles and long ^ ^shots’’ it is better to estimate half
divisions, and for the nearly horizontal two-to-five mile ^ ^shots’’
of triangulation it is frequently worth while to estimate to tenths
of a division. For these long sights, the distance of which is
determined by scaling off the space on the map, there is a theo-
retical error in using tables based on the formula involving one-
half the sine of twice the angle, but there is practically no dis-
crepancy here for the difference between the sine of a small
angle and one half the sine of twice the angle is negligible.

CURVATUEE AND REFRACTION.

No matter what method of determining vertical distances is
used, a correction for curvature and refraction must be applied
to all shots’’ of a mile or more in length. The level datum to

136

KIKTLEY F. MATHEK

which all elevations are referred is a surface having the curva-
ture of the Earth; the line of sight through the telescope in a
level position is tangential to this curved surface; therefore
distant objects appear to be higher above the datum plane than
is actually the case. In the greatly exaggerated figure 12, for
example, the rod reading is increased from C to A. The result
of curvature can be determined with reasonable accuracy. It
varies directly as the square of the distance and may be com-
puted by the formula: Curvature = 0.667 X where D is the
distance in miles.

Fig. 12. Diageam, Greatly Exaggerated
Showing influence of curvature and refraction upon observations for deter-
mining differences in elevation between two points.

Refraction, on the other hand, has the opposite effect- When
light rays pass obliquely from one air stratum to another of
different density they are bent or refracted from their original
position. In figure 12, the light from the target at B, passing
into air strata of increasing density as it travels to the alidade at
the left, is bent downward and enters the telescope as though it
had come by a straight line from A. Thus, the effect of normal
atmospheric refraction is to make distant objects appear higher
than they really are. It, therefore, tends to decrease the curva-
ture correction, as shown in the figure. The amount of refrac;
tion depends upon the density of the air and is, therefore, quite

MANIPULATION OF THE TELESCOPIC ALIDADE

137

variable. ‘ It is much greater near the ground than 3 feet above
it, and generally greater at midday than early in the morning or
late in the afternoon. The empirical valuation ordinarily
placed upon the effects of refraction gives the combined for-
mula: Curvature plus refraction = 0.57135 X D^.

A table showing corrections based on this formula may be
found in the ordinary stadia tables. The correction amounts to
only 0.1 foot for distances of 2200 feet, 0.2 foot for 3125 feet
and 0.5 foot for 4940 but increases rapidly to more than 5 feet at
3 miles and 20 feet at 6 miles. It may safely be disregarded for
the great majority of rod shots,” which will of course be less
than 3000 feet long.

The correction is always a minus quantity and should be
added algebraically after the proper sign has been placed in
front of the vertical distance as instrumentally determined. It
will thus increase the vertical distance for angles of depression
and decrease it for angles of elevation on all fore-sights. Occa-
sionally, for nearly level sights the correction to be applied for
curvature and refraction will be greater than the observed dif-
ference in elevation, and the sign of the vertical distance may
than be changed. No confusion will arise, if the rule stated in
the first sentence of this paragraph be rigidly observed.

ADJUSTMENT OF THE ALIDADE

The most important adjustments of the miniature or ex-
plorer’s alidade, which require attention in the field, are those
for collimation and of the striding level. All other adjustments
are reasonably permanent as made in the factory. It is, how-
ever, well for the instrument man to be able to detect, and if
possible correct, faulty workmanship or damage from mistreat-
ment or accident.

Collimation. The line of sight through the telescope is deter-
mined by the intersection of the cross-hairs, whatever their
position in the tube, and the nodal point in the objective lens.

Obviously, the refraction to which reference is here made is not that of the
direct rays of light from sun or* stars. The. refraction for which correction must
be made in determining sun azimuth is least between 9 a.m. and 3 p.m.

138

KIRTLEY F. MATHER

This line is correctly collimated when it coincides with the opti-
cal axis of the objective. That is, the intersection of the cross-
hairs should remain stationary in the field of vision when the
telescope is rotated on its horizontal axis. The telescope is
mounted between 180-degree stops in the axis-sleeve for this
purpose.

Sight some distant fixed object of small size and center the
cross-hair exactly upon it. The telescope need not be hori-
zontal. Rotate the tube carefully half way round and twist the
prismatic eye-piece back into position. Note whether the cross-
hairs are still centered upon the object. If not, correct half the

discrepancy by means of the dia-
phragm adjusting studs, which may
or may not be concealed beneath a
ferrule which forms a guard against
accident or tampering. In figure 13,
let the original position of the cross-
hairs be represented by the lines
passing through the point A, their
position after rotation of the tele-
scope by the lines passing through
the point B and their collimated
position by the lines passing through
the center of the circle. Move the
vertical hair to left or right by turn-
ing both lateral studs in the same direction, first slightly loosening
the one, then tightening the other. If the alidade is of the erect-
ing type with field reversed from right to left, as is commonly
the case, loosen the screw away from which the vertical hair must
apparently be moved, and tighten the opposite screw. Move
the horizontal hair up or down by turning top and bottom studs
in the same direction, first slightly loosening the one and then
tightening the other. If the eyepiece is of the erecting type,
loosen the screw towards which the horizontal cross-hairs must
apparently be moved and tighten the opposite screw. Having '
corrected half the discrepancy in this way, shift the alidade until
the cross-hairs are again centered upon the distant object, and

Fig. 13. Diagkam Illustrating
THE Adjustment for
COLLIMATION

MANIPULATION OF THE TELESCOPIC ALIDADE

139

rotate the telescope as before. The line of sight should now
remain fixed upon the distant point; if it does not do so, correct
half the apparent error as before. Repeat until the hairs are
properly centered.

The test for collimation should be frequently made. No
. important triangulations should be begun until one is certain
that the cross-hairs are properly located. Should the instru-
ment be subjected to any unusual jar, it must be collimated
before it is again used. In the normal routine of field work the
position of the cross-hairs should be examined at least once each
week.

Striding level. The line of sight when correctly collimated
should be in absolute parallelism to the bubble axis, which is a
line tangential to the curved surface of the striding level vial at
the center of its scale. The two “red metal’^ collars which
support the striding level are trued in the factory to the axis of
rotation defined by the axis-sleeve within which the telescope
rotates. There is very little chance for wear in the sleeve and
the collars themselves are subject to little or no wear, so that
this adjustment is a fairly permanent one. The customary test
of parallelism is therefore simple and rapid. Level the telescope
by the striding level, then turn the level end for end on the
collars. If the bubble does not come to rest in the same position
as before, correct one half of the indicated error with the tan-
gent screw and the other half in the striding level by turning the
set screw in the crotch of one of the wyes with a screw driver.
This will secure parallelism between the bubble axis and the
contact points on the collars, but does not guarantee parallelism
with the line of sight although that has supposedly been pro-
vided for by the maker of the instrument. The reliable test is
that of the peg-method described in most surveying manuals.

Stadia constant. In alidades of the type customarily used by
geologists, the distance between the stadia hairs is fixed in manu-
facture and may not be adjusted in the field. Occasional test
should be made to ensure a close approximation to the fixed

Tracy, Plane Surveying. New York, 1907, pp. 597-600. Metro Manual,
Bausch and Lomb Optical Company, Rochester, N. Y., 1915, pp. 19-20.'

140

KIRTLEY F. MATHER

ratio of 1 : 100 between observed intercept on the rod and distance
from alidade to rod. Read the rod intercept at accurately
measured distances between 100 and 1000 feet from the instru-
ment. If the stadia hairs do not give intercepts sufficiently
accurate for the work in hand, the discrepancy may be remedied
either by preparing a specially graduated rod adapted for the
particular alidade or by computing a constant by which observed
distances must be multiplied in order to give true distances.

Bullseye level. The inner surface of the circular bubble by
means of which the alidade base is made approximately to coin-
cide with the horizon is that of a sphere of long radius. The
alidade base should be parallel to a plane which is tangential to
this sphere at the point defined by the bubble indices. Once
adjusted in the factory it is rarely necessary to rectify the bubble
to keep this parajlelism within the rather broad limits required
for plane table work, but in case of this necessity place the ali-
dade upon a plane surface which is known to be level in all direc-
tions and tighten the screw toward which the bubble seems to
creep..

Telescope axis. In order that the vertical cross-hair shall
travel in a vertical plane, the telescope axis must be adjusted to
horizontality. The requirements for plane table work are suffi-
ciently met by the plumb line test. Carefully level the plane
table and place the alidade along a ruled mark. Hang a plumb
line in the field of view and revolve the table to check against it.
If the vertical hair deviates to the right for instance, reverse the
alidade along the guide line and test on another plumb line
swung in the new field of view. If in this case the vertical hair
deviates an equal amount to the left, the test will show that
while the plane table is not horizontal in the direction of the
telescope axis, the axis itself is correct.

Adjustment of the horizontal axis, should this ever become
necessary, cannot be made in the field. The factory adjust-
ment is considered to be so permanent that an adjusting block is
not provided on alidades. Moreover, it would be difficult to fit
such a contrivance, for the vertical arc is on one extension of the
horizontal axis and the vertical clamp is on the other.

MANIPULATION OF THE TELESCOPIC ALIDADE

141

Fiducial edge. While it is not essential for the fiducial edge
to be more than approximately parallel with the line of sight, it
is important that this edge be straight. Draw a line against
the straight edge and turn the alidade end for end. If the
straight edge coincides perfectly with the test line, the require-
ments are satisfied.

CARE OF THE ALIDADE

Like all instruments of precision the alidade must be handled
with extreme care. Its metal parts are composed almost exclu-
sively of brass, bronze, and ^^red metal,” materials which are
not notably resistant to abrasion. Precautions should con-
stantly be taken, therefore, to keep the bearings free from gritty
particles. The instrument, for example, should never be placed
on the ground or laid on a rock pile. If for any reason it must
be removed from the plane table, return it to its leather case and
close the case, tightly before depositing it anywhere. The
bottom must be kept clean. The instrument in its case should
at all times be protected against jar and shock. The habit of
dropping the alidade to the floor of an automobile to be shaken
around in transit with hammers, specimens, tire tools and other
impedimenta is indefensible. Treat it with at least as much
consideration as one gives to lunch-kit and thermos bottles.

Once or twice a month, bearings, clamps and screws should
be wiped clean with a cloth dampened in a light oil such as
^^3-in-l.” The springs which play against the bearing studs on
the opposite sides from the vernier and tangent screws should
be removed from their housings, wiped clean, stretched a little
and replaced.

If the Stebinger drum is used in determining the elevations,
the tangent screw must be treated with special care. Experience
indicates that very trivial and unobtrusive things may change
the relation of the screw to the arc sufficiently to make a Stebinger
table no longer applicable and necessitate the construction of a
new one. If possible, the gradienter screw should be entirely
withdrawn every week or two and wiped absolutely clean with
the oily cloth. The bearing plate stud against which the point

142

KIKTLEY F. MATHEB

of the micrometer screw pushes must be kept securely tightened.
Should it become loose very erratic readings will result. The
surface of this plate will gradually wear at the point where the
micrometer screw bears against it until a distinct socket is made.
Ultimately this becomes so pronounced that not only does it
throw out the relation of the straight line push of the screw to
the circular movement of the arc, but the point of the screw
will not hit exactly the same spot on successive readings, and as
a result three or four readings from the same station to the same
object will fail to check. When that happens, the bearing plate
should be stirfaced with a file and a new gradienter table
constructed.

The compass needle should always be raised from its pivot
and clamped immediately after it has been used. Protect the
pivot in every way possible, for unless the pivot is sharp and
perfect the needle may be sluggish and unreliable.’’ Place the
alidade as nearly as possible in the magnetic meridian before
releasing the needle, and thus avoid the blow to the needle
resulting from sudden contact with the compass box. The
danger of destroying the polarity of the needle is another reason
for guarding against reckless treatment of the alidade as a whole.
When working in the rain, the compass box is the most vulner-
able part of the instrument. Unless the glass cover is securely
sealed all around, moisture will penetrate the box and put the
needle out of commission by causing it to adhere to the inside of
the glass. If this occurs, the box must be opened, the needle
removed, and all parts thoroughly dried before proceeding with
the work.

THE IMPORTANCE OF DRAINAGE AREA IN ESTI-
MATING THE POSSIBILITIES OF PETROLEUM
PRODUCTION FROM AN ANTICLINAL
STRUCTURE

KIRTLEY F. MATHER and MAURICE G. MEHL

So fully is the general dependence of commercial accumula-
tions of petroleum on rock structure accepted among the oil
fraternity that the average report setting forth the possibilities
of oil and gas production properly centers about the structure
of the region concerned. Experience has indicated that accumu-
lations of petroleum usually coincide with certain variations in
the attitude of the reservoir rocks; mobility of liquid and gaseous
hydrocarbons in tilted porous beds has been recognized to the
extent that these structures are looked upon as entrapping
basins’’ or checks to the upward movement of hydrocarbons
along the inclined strata. Attention, however, is usually focused
on the nature of the accumulating structure or trap rather than
on the nature of .the area from which petroleum or gas could have
been gathered. In the more common descriptions of a favorable
structure, concise statements are made concerning its effective-
ness as a trap as indicated by the amount of closure and the
size of the area beneath which accumulations of oil or gas should
occur; too often nothing is stated concerning the possible feeding
ground which may have served as the source from which the oil
or gas must come. Account is seldom taken of the fact that a
large and effective accumulating structure may be so situated
that it could have drawn an accumulation of petroleum from
only a very small area; or, as we are here using the term, that
the “drainage area” may be of such slight extent as to be in-
sufficient to supply all the oil or gas which could be retained in
the structural trap.

A map showing geologic structure by means of contour lines
should therefore convey two items of valuable information to the

143

144

KIRTLEY F. MATHER AND MAURICE G. MEHL

man interested in the oil and gas resources of the region repre-
sented: (1) the location and extent of the areas beneath which
oil and gas migrating up the dip of the reservoir rocks would
be trapped; (2) the size of the area from which the mobile hydro-
carbons might be expected to move toward this trap. The first
of these is important in determining the location of drill holes;
the second is an equally important factor in determining the
volume of possible production from the favorable structure.

To those uninitiated into the mysteries of contour lines — and
many such must constantly be dealt with in the petroleum
industry — neither of these facts is apparent from the ordinary
structure contour map. If the structure of the region be at all
complicated, even the connoisseur must spend much time in a
careful analysis of the contour lines before he can visualize the
structure in all its details and grasp adequately the information
thereby set forth. It has been found helpful in the interpreta-
tion of structure contours to draft an auxiliary map so planned
as immediately to focus the attention upon these two facts
undistracted by a maze of lines.

To illustrate the method and the result, there is presented
herewith a structure contour map (plate XIX) of the four town-
ships in the southwestern corner of the Pawhuska Quadrangle,
Osage County, Oklahoma. The contour lines, redrawn from the
township plats prepared by Heald, Winchester, Bowen, Condit,
Emery, Clark and Mather, ^ represent a region of complicated
structure comprising 31 anticlines and domes of sufficient indi-
viduality to be given distinctive names. Accompanying this
contour map is an oversheet reproduced from a map prepared
by N. L. Thomas, a member of our class in petroleum geology,
delineating the area of each inverted basin and drainage tract.
The space embraced within the lowest closed contour line on
each anticlinal fold is diagonally ruled; the direction of migration
of oil or gas in the reservoir rock is indicated by arrows; the feed-
ing ground from which the hydrocarbons, accumulated on or

1 Structure and oil and gas resources of the Osage Reservation, Oklahoma,
Twps. 24 and 25 N., Rs. 8 and 9 E., U. S. Geol. Survey, Bull. 686, parts E, M and
P, 1918-1919.

IMPOKTANCE OF DRAINAGE AREA

145

near the crest of each fold, may have been drawn is enclosed by
a sinuous line.

A merely desultory glance at the oversheet is sufficient to
enable one to grasp the import of the structure. of the region so
far as its influence upon the accumulation of oil and gas is con-
cerned. If we assume that a suitably porous reservoir stratum
is continuous beneath the surface of the entire region, that
hydrocarbons were at one time disseminated uniformly through-
out that stratum, and that they have subsequently moved up
the dip in obedience to gravitational sorting, we may conclude
that oil and gas will be concentrated in and near the shaded
tracts in amounts proportional to the size of the feeding grounds
or drainage areas.

Such a map obviously fails to present a complete picture of
the geologic structure of the region. Where the rocks are faulted,
as they are in the area chosen for illustrative purposes, the struc-
tural drainage areas may be outlined only after making certain
unsupported assumptions as to the effect of faults upon the
movement of the hydrocarbons. Here, for example, it was as-
sumed that faults whose maximum throw at the earth’s surface
was less than 30 feet would not have prevented the up-dip
migration of oil or gas, while a fault with a throw of 50 to 70
feet — such as the one which slices the Ducotey anticline in
15-25-9 — is believed to have effectually halted such migration.
Again, change of dip angle without any actual reversal of dip
direction or closure of contour lines may be all that is needed
to trap the migrant hydrocarbons; but it is impossible to state
in advance how much flattening of the beds is necessary to permit
a structural terrace to localize an oil or gas accumulation. In
the illustrative case, it was decided to neglect all changes of
dip angle and consider as traps only true domes or doubly plung-
ing anticlines. The drainage outline map must therefore be
used only in connection with the contour map on which it is
based; it is to serve as an aid to the ready interpretation of the
structure contours, not as an independent entity.

Possibly the greatest value of such a map to the petroleum
geologist is that it brings into merited prominence the factor of

146

KIRTLEY F. MATHER AND MAURICE G. MEHL

drainage area. In our illustration, for example, the Wheeler
dome near the center of 24-8 has about the same area within
the lowest closed contouf line as has the northeastern bump on
the Wooster anticline in 27-25-9; the latter has 50 feet of clo-
sure, the former only 30, and hence the latter would be considered
by many as a more valuable structure; but the oversheet draws
attention to the fact that the drainage area contributory to the
Whoeler dome is more than twice that which may have fed this
portion of the Wooster anticline, and hence, other things being
equal, the Wheeler dome should contain more than twice as
much oil.

Outlining the possible gathering ground for each anticlinal
fold, as on the accompanying plate, serves also to depict clearly
certain of the peculiarities of distribution of producing wells in
the Osage Reservation. In general, it is noted that the folds
are so closely crowded that the drainage areas are all very small.
In certain parts of the Reservation good production is obtained
from pools so situated that none of the oil which they contain
could have come from a greater distance than miles. On
the average, oil beneath Osage County has probably migrated
only 2 or 3 miles from its point of entrance into the reservoir
stratum to its resting place in an oil pool. Few accumulations
are so situated as to have drawn oil or gas from points more
remote than 4 miles.

Again, the asymetrical situation of the effective trap, almost
invariably much nearer the eastern than the western margin of
the drainage area, is forcibly presented. Experience indicates
that production extends much farther down the longer flanks of
the anticlinal folds than the shorter. Where the east flank is
less than a mile long, little oil is found east of the crest of the
fold; the area from which that portion of the anticline may have
been supplied was insufficient to permit a commercial accumu-
lation. In general, the amount of production from the various
parts of an anticlinal fold seems to depend largely upon the
length of the slope from the margin of the drainage area.

;^Map areas ins southwestern tpor!

s/ iilvenlijed txaps for, .gas wthin.clcfefed

Bulletin Scientific Latooratorle* Denison Oniverelty, Vot. XIX

.flLATE XIXA

Map showing structural drainage aveasiin southwestern portion of Pavrhuska qliadlaidgle,iQklahomaL .iShaided areas are
inverted traps foEt oil and gas within closed contours; arrows indic^U direotion o? migration of ioil and gasl

Bulletin Scientific Laboratories Denison University, Vol. XIX

PLATE XIXA

Map showing structural drainage areas in southwestern portion of Pawhuska quadrangle, Oklahoma. Shaded areas are
invertjed traps for oil and gas within closed contours; arrows indicate direction of migration of oil and gas

N. '

Map showing geologic structure of southwestern portion of Pawhuska quadrangle, Oklahoma. Contour interval, 10 feet;
scale, 1:114,500. Redrawn from Plates VII, XXIV, XXV, and XXXII, Bull. 686, U. S. Geol. Survey, 1918-1919

,V'

: . '’O ■•iv i,. iv' >■■■>■' rvr') );r',V7dl7o?^ '. y :*!■; -i

■ .■■■; / j .1-::^) /JiiH /tL/'/A {'iiT ,V.“A r.'.vj.t'iiX!. ■ •.OO".,-' i i ..1

• J , , ■ ■ • ''

.'Ki

VOLUME XIX, NO. 3

MAY, 1920

Denison University Bulletin

Journal

OF THE

Scientific Laboratories,

Volume XIX Articles 9-12 Pages 147 to 224

9. Psychological Factors in Vocational Guidance. By Thomas A. Lewis 147

10. The Use of Models in the Interpretation of Data for Determining

the Structure of Bedded Rocks. By Maurice G. Mehl 157

11. Some Suggestions for Indicating Drilling Operations. By Maurice

G. Mehl 169

12. The Kimmswick and Plattin Limestones of Northeastern Missouri.

By Aug. F. Foerste 175

The University Bulletin is issued bi-monthly, and is entered at the Granville, Ohio,
Postoffice as mail matter of the second class.

JOURNAL

OF THE

SCIENTIFIC LABORATORIES

OF

DENISON UNIVERSITY

Edited by

KIRTLEY F. MATHER

Permanent Seeretary, Denison Scientific Association,
Granville, Ohio

Acting Edito

WILLIAM CLARENCE EBAUGH

The entire file of volumes 1 to 13 was destroyed by fire; no publications issued prior to
1907 are now available. Volumes 14 to date may be obtained from the editor at $2.00 per
volume, with the exception of volume 15, the price of which is $1.00. Separate parts, as listed
below, may be purchased at the prices indicated.

VOLUME 14

Articles 1-5, pp. 1-60; Nov., 1908 $0.50

Pre-Wisconsin drift in the Finger Lake Region of New York; F. Carney. 16 pp., 4 figs.

An esker group south of Dayton, Ohio; Earl R. Scheffel. 15 pp.. 6 figs.

Wave-cut terraces in Keuka Valley, older than the recession stage of Wisconsin ice; F. Carney. 12 pp., 3 figs.

A form of outwash drift; F. Carney. 8 pp., 1 fig.

State geological surveys and practical geography; F. Carney. 6 pp.

Articles 6-10, pp. 61-188; April, 1909 $1.00

Fossils from the Silurian formations of Tennessee, Indiana, and Kentucky; Aug. F. Foerste. 56 pp., 4 plates.
Studies on Babbit and other alloys; 10 pp. J. A. Baker.

A statigraphical study of Mary Ann Township, Licking County, O. 28 pp., 15 figs. F. Carney.

Significance of drainage changes near Granville, Ohio;' Earl R. Scheffel. 17 pp., 2 figs.

Age of the Licking Narrows; K. F. Mather. 13 pp., 5 figs.

Articles 11-16, pp. 189-287; June, 1909 $0.75

A spectrometer for electromagnetic radiation; A. D. Cole. 10 pp., 6 figs.

The development of the idea of glacial erosion in America; F. Carney. 10 pp.

Preliminary notes on Cincinnatian fossils; Aug. F. Foerste. 20 pp., 1 plate.

Notes on Spondylomorum Quaternarium Ehrenb; M. E. Stickney. 5 pp., 1 plate.

The reaction to tactile stimuli and the development of the swimming movement in embryos of Diemyctylus torsus,
Eschscholtz; G. E. Coghill. 21 pp., 6 figs.

The raised beaches of the Berea, Cleveland, and Euclid sheets, Ohio. F. Carney. 25 pp., 5 figs.

Articles 17-18, pp. 289-442; November, 1909 • $1.00

Preliminary notes on Cincinnatian and Lexington fossils; Aug. F. Foerste. 45 pp., 5 plates.

The Pleistocene geology of the Moravia Quadrangle, New York; Frank Carney. 105 pp., 27 figs.

VOLUME 15

Article 1, pp. 1-100; March, 1910 $1.00

Bulletin in cc^memoration of Clarence Luther Herrick.

PSYCHOLOGICAL FACTORS IN VOCATIONAL
GUIDANCE!

THOMAS A. LEWIS

Vocational guidance is a short name for ^The conservation of the
energies and talents of human workers/^ The object is to secure
for the new generation, by expert assistance, that occupational
adjustment which reduces waste and worry to a minimum. It is
an attempt to afford boys and girls and young people the aid so
much needed by them in order that they may choose the vocations
in which they will have the best chance for personal success and
for public usefulness. Putting the matter concretely, it is an
attempt to prevent such situations as that typified by the firm
which utilizes the services of a thousand salesmen, but ^To keep
the ranks of that thousand full hires from five to seven thousand
men a year.’^

The main field for vocational guidance is in schools and col
leges, because by centering the undertaking there practically
every person who has yet to choose a vocation may be reached
and that at an opportune time. With guidance machinery
installed in the later elementary grades the 40 per cent that
drops out as soon as the law allows will not fail to receive its
benefits, and with this machinery still operating in the college
those who make their decisions at this relatively late age will
not be neglected. Vocational guidance in connection with
manual vocations extends out into the occupation in the case
of those pupils who enter the busy world early and need ^Tol-
low-up’^ supervision to keep them from getting trapped in ‘‘blind-
alley’^ jobs; and in the case of students in educational institutions
where the “part-time” plan is in operation, and where the stu-
dent divides his time between school and work. In this latter

1 Address of the retiring President at the regular semi-monthly meeting of the
Denison Scientific Association, October 7, 1919.

147

148

THOMAS A. LEWIS

instance guidance takes its cue as much from the way the indi-
vidual gets along ^^on the job” as from the run of things in his
study-life. There is an extreme swing of vocational guidance to
the occupational end in the case where the psychological expert
stands at the door of the business concern and by use of various
kinds of tests attempts to find the right men for the different
places, shutting out the others.

There is more to vocational guidance, of course, than just
what is being done by the psychologist in his diagnostic testing.
In the opinion of the Commission on the Reorganization of
Secondary Education, vocational guidance should be a continu-
ous process designed to help the individual to choose, to plan his
preparation for, to enter upon, and to make progress in an occu-
pation.” That this task is many-sided and therefore calls for
the cooperation of many minds is indicated by the nature of the
program set by the committee for carrying it through. The
program consists of eight steps, as follows:

1. Survey of the world’s work.

2. Studying and testing pupils’ possibilities.

3. Guidance in choice and rechoice of vocation.

4. Guidance with reference to preparation for vocation.

5. Guidance in entering upon work; that is, placement.”

6. Guidance in employment; that is, “employment super-
vision.”

7. Progressive modification of school practices.

8. Progressive modification of economic conditions.

' The outline, it will be seen, assigns sufficient work for teacher,
school administrator, vocational counsellor, parent, psycholo-
gist, and others. It is only to be noted that the psychologist
is assigned a particular part, namely, “studying and testing
pupils’ possibilities.” Not that he alone is assigned this topic,
though there is evidence that his services here are going to
increase in volume and reliability.

The late Prof. Hugo Muensterberg, of Harvard University,
was very optimistic about the future of vocational psychology.
He thought that the problem of vocational guidance “had

PSYCHOLOGICAL FACTORS IN VOCATIONAL GUIDANCE 149

already been handed over from the vocational counsellors to the
experimental psychologists.’’ In his mind, ^Hhe laboratory
method” was as superior to the ^^mere-impression” method as
^Hhe microscope is superior to the human eye.” As a rule the
investigators in this line are more moderate in their claims and
expectations, and for the two reasons, namely that (1) the
technique of mental measurement is not so highly perfected as
the microscope and (2) the material to be dealt with is of the
most complex kind.

The committee on vocational guidance appointed by the
National Education Association makes a * three-fold classifi-
cation of the experimental work being carried on by the voca-
tional psychologist, namely:

(1) The attempt to supply the employer with tests that will enable
him to select from a large number of applicants those most likely to
succeed in a given position (vocational selection) ; (2) the attempt to
determine specific vocational abilities — that is, which of several occu-
pations would be the best one for a given individual to follow; (3) the
attempt to develop tests for the measurement of general intelligence.

Professor Muensterberg, who was one of the first men in this
country to go at the matter of vocational guidance laboratory
fashion, performed experiments to weed out applicants and also
to discover personal aptitude. His tests (which were not of the
general intelligence variety, but were tests of reaction time,
association, attention, etc.) were applied, as he said, from the
side of ^The scientific manager who seeks the best man for the
work; and from the side of the vocational counsellor who seeks
the best work for the man.” He thought that by so doing the
interests of both sides were provided for. Being a pioneer in
this new world of discovery, Muensterberg did not blaze the
way very far, but what he did was of practical value and rather
significant. His investigations were concerned with finding out
what sort of equipment was required of a person who could be
counted on to succeed as a typesetter, a motorman, a telephone
operator, etc. His methods and results in the case of -the motor-
man are typical. Assuming that for motormen on street rail-

150

THOMAS A. LEWIS

ways essential ability consists in the power to combine

continuous attention with an impulse to quick reaction, and
with a certain imagination by which the movements of pedes-
trians and vehicles are foreseen/’ he contrived a device whereby
it was possible to test a man for these specific characteristics.
There was a crank which the subject turned, and red and black
puppet figures that appeared on a passing screen in different
combinations, and the noting of certain particular combinations
seemed to be the thing that told the tale. The number of the
mistakes made in this particular and the rapidity in turning the
crank were measured. ‘‘Experienced motormen felt, in carry-
ing out this experiment,” says Muensterberg, “that the mental
attitude was indeed quite similar to that of their function on the
street.” He remarks upon the fact that “13 per cent of the
gross receipts of some roads go for damages due to avoidable
accidents,” and significantly adds that his “experiments resulted
in the rejection of one-fourth of the applicants for positions as
motormen.”

Other men engaged in psychological research have also become
greatly interested in recent years in the practical possibilities of
the science, and in some institutions of higher education (Car-
negie Institute of Technology, for example) applied psychology
has assumed large proportions.

But it is the service performed in connection with the organi-
zation of our recent Army that vocational psychology stands out.
Psychology here undertook a task of mental engineering which
was on a scale so vast as to require of the specialists in that
field the abandonment for the duration of the war of many or
all of their other duties. The classification of the membership
of the Army on the basis of trade abilities and general intelli-
gence and officer qualities was largely the psychologist’s respon-
sibility. The dual problem (set by Muensterberg) of studying
the man and the occupation as the prime fundamental in voca-
tional guidance, was attacked in great earnestness, and with the
result that it became possible to select officers with some assur-
ance that right selections were being made, to classify recruits
according to their capacities both to learn what a soldier must

PSYCHOLOGICAL FACTORS IN VOCATIONAL GUIDANCE 151

know and to do what a soldier must do, and ^Ho locate every
man that had any kind of special skill that the Army might
need.’^ The methods followed in working up these different
tests, as well as the results obtained by their use, are significant
as indicating the way the thing must be gone at if any contribu-
tion to vocational guidance is to be made from this source. In
formulating the trade tests, to use this set of tests as an example.

The committee sought material from all promising sources. These
included skilled mechanics in all the trades represented, trade-union
officials, employment managers, factory superintendents and foremen,
the United States Bureau of Labor Statistics, civil service examiners,
and Army officers in all branches of the service.

A first-hand study was made of the mechanic on his job. With the
assistance of skilled workers in each trade, the essential elements of
the processes involved were selected and classified. These were then
translated into questions which might be used to test the capacity of
the worker.

In addition to the oral test, here described, there were picture
and performance tests. ^^The picture test required the candi-
date to identify certain technical processes and details relating
to the trade, and the performance test required the candidate
to carry through some operation, or construct some piece of
work, which involved the essential processes of the trade.”

Raymond Dodge points out the fact that

These tests standardized for the first time in America the classifi-
cation of novices, apprentices, journeymen, and experts in the most
important trades. The scientific care with which these trade tests were
prepared may be indicated by the fact that each test before it was
adopted passed through a process of development, trial, and evaluation
consisting of twelve distinct stages.

A question in one of these finished-up tests for telephone
repair men is given by Randall in the American Magazine for
April, 1919:

Some of the questions (the trade test questions) are very interesting.
For example here is one that will set off a journej'-man telephone repair

152

THOMAS A. LEWIS

man from an apprentice: ^^Why is is that when a subscriber tips the
telephone instrument in talking, the party at the other end does not
hear so well?”

The answer is that the sound box in the instrument contains a lot
of little carbon granules which, when put under pressure by the sound
waves of the voice, transmit electricity. The harder the pressure the
more electricity they transmit, and the better the voice is carried.
Tip the instrument, and the granules, which are loosely packed, are
displaced, and the person at the other end says, don’t hear, you’ll
have to speak a little louder.”

A journeyman repair man knows that, because he is expected to
open sound boxes and fix them when they are wrong. An apprentice is
forbidden, under any circumstances, to open a sound box. His func-
tions are limited to taking a faulty sound box out and putting a perfect
one in; and he never sees the inside of one of them.

To the oral tests were added picture tests. One of these — the test
for typewriter repair men — I myself took. A four-page leaflet was
put in my hands, containing on each page a picture of one section of a
typewriter. There were twenty questions on this order: ‘What is the
purpose of the screw marked B?’ ‘If your carriage was running too
slow what part of the machine would you adjust?’ The test proved
that as a typewriter repair man I rank as a low apprentice — which is
about right.

In the same concrete fashion, Randall gives an example of a
performance test — one for an automobile repair man. In this
case the man was a ^Hrame-up’’ — a person coached for the occa-
sion just to see if he could not weather the automobile test,
though in fact only a novice. Randall says:

He appeared in camp, and on the oral tests made a perfect record,
which was so unusual as to excite the admiration of the examiner.
The result was that he was led into a tent where a certain part of an
automobile lay on the table in pieces, and left to put it together. The
examiner discovered him a half-hour later. The part was screwed
together and looked pretty workmanlike. But the candidate had
forgotten entirely to put in any packing, and he was cudgeling his
brain to discover what the two springs and a bolt for which he had
found no place could possibly be intended for.

PSYCHOLOGICAL FACTORS IN VOCATIONAL GUIDANCE 153

If both the tests for general intelligence and the trade tests
could be incorporated in a vocational guidance program for the
school and the college it would be possible to estimate the indi-
vidual’s all-round capacity as well as any special capacity that
he might have. The trade tests to be used with novices or
vocationally untrained persons, as would be the case here, would
have to be framed to sound native bent, and not to sound (as
was the case in the Army) the capacity the person had by virtue
of specific vocational training. Not much has so far been done
along this line and it may be too much to expect that a great
deal can be done. Professor Seashore of the University of Iowa
seems to have succeeded in testing for musical ability, and there
are a number of men who are busy trying to contrive tests that
will have forecasting value in other directions. Dean Schneider
of the College of Engineering, University of Cincinnati, is scep-
tical and maintains that the only way to test for vocational
fitness or unfitness is ^^on the job.” It may be, however, that
the remarkable success of the trade tests in the Army — con-
futing the sceptic — will have both a heartening and enlightening
effect, and that in consequence real things will be achieved
before many years in creating and applying similar tests in
educational institutions. .

With respect to the general intelligence tests, it seems fair to
say that as a rule they do really test, though in a more or less
rough way. As adapted for military use (under the name Army
recruit test) they counted for something. Thorndike, one of
the men who figured prominently in this adaptation, and the
man into whose hands was given the preparation of the tests
for entrance to Columbia University, while acknowledging the
large possibility for error in the results obtained through the use
of tests for general intelligence, still holds that ^The test score
may always be of great value, since it is a clear addition to the
available impressionistic knowledge; it taps a new source of
information.”

A few of the tests in which most faith is placed may be added
here. They are of such rank as to have been closely patterned
after in the Army. Reference to the army tests can only be

154

TllOMAS A. LEWIS

indirect as their publication is forbidden under penalty. These
examples are taken from Terman^s The Measurement of Intel-
ligence.

First, the ^'dissected-sentence’’ test. The sentences are to be
put in right order.

(a) For the started an we country early at hour.

(b) To asked paper my teacher correct I my.

(c) A defends dog good his bravely master. . . . . false true

In the corresponding army test, which contained false as well
as true statements, the men had not only to rearrange the dis-
arranged words but had also to indicate whether true or false,
by underlining as in sentence (c) above.

A second test is that of detecting absurdities,’’ used by the
army also, only with modified content and with somewhat differ-
ent instructions. In the Army, those taking the test were told
to write the letter before each of the statements which could
not possibly be true.

(a) A man said: ‘T know a road from my house to the city which
is downhill all the way to the city and downhill all the way back home.”

(b) An engineer said that the more cars he had on his train the
faster he could go.

(c) Yesterday the police found the body of a girl cut in eighteen
pieces. They believe that she killed herself.

The following test, framed for testing salesman, and closely
parallel to one of the army tests, is given by Bruce Barton in
the American Magazine for March, 1919, There is a time limit
set as an index of mentality of different grades. For example,
^To take less than 100 seconds is to be in the superior 25 per
cent.” The individual is graded also on accuracy. The test
plainly calls for variegated mental behavior, such as close obser-
vation, the ability to hold several things in mind at once, careful
and quick use of one’s judgment, etc.

With your pencil make a dot over any one of these letters F G H I J
and a comma after the longest of these three words: boy mother girl.

PSYCHOLOGICAL FACTORS IN VOCATIONAL GUIDANCE 155

Then, if Christmas comes in March, make a cross right here ....
but if not, pass along to the next question, and tell where the sun rises.
. . . . If you believe that Edison discovered America, cross out
what you just wrote, but if it was some one else, put in a number to
complete this sentence: horse has .... feet.” Write yes,

no matter whether China is in Africa or not . . . .; and then

give a wrong answer to this question: ‘‘How many days are there in a
week?” .... Write any letter except g just after this comma,
and then WTite no if 2 times 5 are 10 ... . Now, if Tuesday

comes after Monday, make two crosses here . . . .; but if not

make a circle here .... or else a square here .... Be
sure to make three crosses between these two names of boys: George
. . . . Henry. Notice these two numbers: 3, 5. If iron is heavier

than water, write the larger number here . . . ., but if iron is

lighter write the smaller number here .... Show by a cross
when the nights are longer; in summer? .... in winter?
. . . . Give the correct answer to this question: “Does water
run uphill? .... and repeat your answer here .... Do
nothing here (5 + 7 = . . . .), unless you skipped the preceding

question; but write the first letter of your first name, and the last
letter of your last name at the end of this line: ....

There is need for improvement in the general intelligence tests
both in their character and in their use. Thorndike points out
the fact that they are not, as their name might indicate, tests of
“all intellectual abilities,’’ but only of such abilities as are
involved “in learning from lectures and books and dealing with
ideas and symbols.” He says, illustrating his point:

In the army test Alpha, a test whose data are largely words and
numbers and whose score is largely determined by speed, stenogra-
phers and typists score enormously better than tool makers, gun-
smiths and locomotive engineers, etc., and almost on a level with civil
and mechanical engineers and physicians.

It is his opinion, therefore, that “our present standard tests
of intelligence need to be greatly extended and improved; and
expectations from them need to be kept modestly in line with
the facts.” One other caution may be appended, namely, that
not even vocational psychology can do more toward guiding

156

THOMAS A. LEWIS

the individual in choosing a vocation than to point out the direc-
tion in which it appears his nature will block the way with least
physical and mental and temperamental handicaps. He may
have sufficient unmeasurable will power, or tenacity, or grit to
succeed though he goes into a vocation for which he seems least
fitted, but he can hardly succeed so well.

Finally, it may be said that the thing which holds out the
most promise for the actual realization of the vocational psychol-
ogist’s dream is the increasing establishment in educational insti-
tutions of a personnel bureau, corresponding to a similar bureau
in the Army. This will give vocational guidance an official
standing, and all the means and methods available will be laid
hold of and be turned to account or thrown overboard. The
bureau will make use not only of the technique at hand, but
^^will initiate and encourage research” to the end that trade
(vocational) tests may be adapted and invented, the general
intelligence tests ^^be expanded and improved,” and other
things be done that through vocational guidance “the pupil
(and the student) may be helped to discover his own capacities,
aptitudes, and interests, may learn about the character and
conditions of occupational life, and may himself arrive at an
intelligent vocational decision.”

THE USE OF MODELS IN THE INTERPRETATION
OF DATA FOR DETERMINING THE
STRUCTURE OF BEDDED ROCKS

MAURICE G. MEHL

Of the various ways to describe the structure of sedimentary
beds graphically, that of showing the configuration of the datum
bed by contours is by far the more common and, for most cases,
altogether the more satisfactory method. Ordinarily the struc-
tural contour map is drawn from irregularly scattered observat-
ions— elevations on a key bed or on other horizons from which
the elevation of this bed may be calculated.

At best the determination of the structure of a region is an
approximation. It is rare indeed that a single bed has unlimited
exposures over a large area and even with supplementary obser-
vations from sub- and superadjacent beds, within a compara-
tively large proportion of almost any region, no data are to be
had. Usually, then, the observations are closely crowded along
the limited outcrops and are relatively far apart over most of
the area.

Although in general the principles of contouring topography
and structure are the same, the details are somewhat different.
Since topographic contours attempt to represent accurately the
configuration of a surface, every point on that surface is a valid
observation and the greater the number of observations the
more accurate the resulting contour map. In contouring the
structure, although the contours represent a certain condition
of the bed it is not the configuration of its surface. What is to
be shown is the structural attitude, the attitude of the general
plane of the bed as it has been modified by diastrophism alone.
This is not necessarily the upper or lower surface nor even the
present attitude of the general plane of the bed as is pointed out
later.

157

158

MAURICE G. MEHL

One cannot always be sure, for instance, that an elevation on
a bed indicates its structural attitude. Within a region of even
moderate relief, if the rock series has the normal complement of
shales, there is abundant opportunity for their creep or slump
with a consequent down-slope bending of the competent beds.
One has only to observe this tendency of limestones to conform
to the slope of the hill, as it is shown in a fresh cut across a
ridge, to realize the possibility of error in this direction.

As a rule, the top of some conspicuous bed is selected as the
datum plane and the observations are confined to this horizon as
fully as possible. Few beds maintain their full thickness for any
considerable distance, however, and often they are notably
irregular. In Wilson County, Kansas, the writer has observed
the Stanton limestone reduced from more than 30 feet in thick-
ness to nothing within comparatively short distances. Or again,
in Anderson County, Kansas, a Sub-Allen limestone which
forms a conspicuous cap of as much as 40 feet in thickness
over the ridges of a considerable area is very thin or entirely
lacking within half a mile from what is essentially its greatest
development.

Obviously, closely spaced observations on such an irregular
surface do not give a true picture of the structure of the region.
If the datum horizon is displaced 5 feet by slump or the irregu-
lar surface of the bed, a decidedly abnormal dip is indicated
between this point and another observation point nearby which
is taken on the properly related plane. An error of 5 feet if dis-
tributed over a large distance is not far from the true configura-
tion of the datum bed. It would appear that observation points
can be spaced too closely for the accurate determination of the
structure.

There is also some question as to the desirability of showing
other than the larger features in the configuration of the beds in
an attempt to show the structure. Even if one could be sure of
the correctness of the closely spaced observations it is doubtful
if the minor changes in dip which these observations show would
affect the generally parallel beds at any appreciable distance
above or below the datum bed.

DETERMINING THE STRUCTURE OF BEDDED ROCKS 159

Granting, however, that all the observed elevations do indicate
the true effective structure, there is no assurance that the data will
be interpreted in a like manner by two different workers. In
the writer^s experience, a dozen students using the same data
will present nearly as many variations in the interpretation of
the structure. With common methods there seem to be always
several possible interpretations of the same data, although but
rarely more than one logical interpretation presents itself if the
observation points are in any sense adequate.

An excellent illustration is to be found in a discussion by
K. C. Heald.i In this discussion it is pointed out that two

Fig. 1. Structural contour map of a region in which data are lacking at cer-
tain critical points. Cross marks with figures are observation points on the
datum bed. (After Heald.)

Fig. 2. Structural contour map of the same data as presented in figure 1.
Under the methods commonly employed this almost opposite interpretation of
the data is permissible if not even logical. (After Heald.)

almost opposite interpretations may be made from the same data.
Figures 1 and 2 show the same elevations with an entirely dif-
ferent interpretation. Aside from the fact that the structure
shown in figure 2 is a very exceptional expression of deforma-
tion, there is apparently no reason why either of these inter-
pretations might not be considered correct.

In determining the structure of a region much must always be
taken for granted. It is assumed, for instance, that between two
adjacent observation points the dip is essentially uniform. This

1 Geologic structure of the northwestern part of the Pawhuska Quadrangle,
Oklahoma. U. S. G. S. Bull 691 C, p. 80-81, 1918.

160

MAURICE G. MEHL

assumption is necessary if one is to avoid a number of interpreta-
tions comparable to the whims of the various workers. Further-
more, this is found to be justified within limits by experience.
It is only because of the fact that the datum plane is thought
of as a series of intersecting planes, each one comparatively
large, that it may be in any sense adequately represented by
contours.

For all practical purposes any surface, no matter how irregular,
can be resolved into a series of planes. If the surface is curved at

30

Fig. 3. Application of the triangle system to the data, presented in figures 1
and 2. The letters A to L indicate the triangles into which the surface is divided
by dashed (continuous lines where the edge of the triangles is coincident with a
contour) lines. The continuous lines are the contours that appear on the
unwarped triangular surfaces.

every part, as in a sphere, the closest representation by planes is
that of the greatest number of planes each of the least extent.
Three points on a plane, providing they are not in a straight
line, fix the position of that plane. If, then, lines are drawn to
connect each of three adjacent observation points on a datum
bed, that bed will be divided into a series of triangular planes,
the greatest number of planes which the data permits. If it is
agreed that each set of three points fixes the position of an
essentially flat plane which they outline, and this agreement is

DETERMINING THE STRUCTURE OF BEDDED ROCKS 161

arbitrarily adhered to, there can be but slight variation in the
interpretation of any structure represented by a series of isolated
elevations.

In figure 3, as in figures 1 and 2, the same data are again
utilized, but here the principle of intersecting planes is recog-
nized. The observation points are made to outline the several
triangular planes A to L, and each plane is contoured indepen-
dently. The attitude of the triangles A, B, C, D, K, and L is
evident. It is further evident that the corners of the tri-

angles, C, jD, and G are tilted down to form an inclosed depres-
sion. Likewise, the point represented by the ^^60” corners of
the triangles E, F, G, H, /, and J represents an elevation. It is
obvious then, that there can be but one interpretation of the

30

Fig. 4. Structural contour map of the same data as that presented in figures
I and 2 as it would appear after the sharp intersections of the triangular planes
have been ‘‘smoothed out,”

gross structure of the region. The only possible error is that in
the variation in size and the exact position of the small depres-
sion marked by the 50 foot contour and the small elevation
encircled by the 60 foot contour.

The division of the surface into triangles either graphically or
mentally gives the resulting contours a decidedly stiff’ ^ or
mechanical appearance. It is evident that the planes must be
warped and their intersections smoothed out” so that any
cross section except where broken by faulting shall be free from
abrupt changes in direction.

For some time the writer has been practicing a system of
modeling which includes all the advantages of the triangle system
and at the same time eliminates most of its crudities.

162

MAURICE G. MEHL

THE CONSTRUCTION OF STRUCTURE MODELS

As a first step in the construction of the model a base sheet is
prepared from the plane table sheets. The observation points are
properly located and the elevation of the datum plane indicated
at each observation. The sheet is attached to a soft board and
at each observation point a peg is driven so that its length rep-
resents the elevation of the bed at that point. Obviously the

Fig. 5. “Peg” model of the data utilized in the construction of the structure
map in Plate XX.

board represents a horizontal reference plane the elevation of
which is anything the worker may choose, usually slightly less
than the lowest observation point.

After all the pegs are fixed it is a comparatively simple matter
to model the surface which they represent by filling in to their
tops with fine moist sand or modeling clay. The resulting sur-
face is full of crudities for it is composed of a series of fiat tri-
angular surfaces extending between each set of three adjacent
points. By slight additions of material in places and the re-

DETERMINING THE STRUCTURE OF BEDDED ROCKS 163

moval of some of the filler in others the surface soon shapes itself
into one of broad curves simulating those of the average deformed
beds.

There are many short cuts in the technique of model making
with which the worker will become familiar after a little practice.
The relation of the vertical to the horizontal scale makes no
essential difference for if the work is accurately done the resulting
contours will always be the same. Obviously, the model must
be contoured with the same vertical scale as that used in its
construction and the contours must be reckoned and numbered
in reference to the assumed elevation of the wood base. The
writer has found that on the average a vertical scale which
gives a relief of about 3 inches to a model with a base of 16
inches is very desirable. This makes convenient the use of a
horizontal scale of 2 or 4 inches to the mile, the usual scales
used in plane table work. The models of this size or in units of
this size permit the representation of 16 or more square miles,
about the average involved in the report of the consulting
petroleum geologist.

It is often desirable to preserve the model in the form of a
plaster cast. In making casts, care should be taken to preserve
the proper relations between the horizontal reference plane and
the surface representing the structure. Perhaps the most simple
way of accomplishing this is to level the base and then make the
negative by pouring plaster of paris over the model (which has
been confined by sides of suitable height) till the plaster entirely
covers the sand and in its liquid state forms a level surface.
When the negative is reversed, insulated, and confined within a
suitable frame, the positive may be poured and if the lower side
of the reversed negative is horizontal the liquid plaster of the
positive will form a flat surface with which the structural surface
will have the proper attitude. It has been found that for most
work a thin soft soap makes the best insulation between nega-
tive and cast.

For contouring the writer has found very convenient an appa-
ratus such as that shown in figure 6. A less elaborate outlay
answers the purpose well and is, perhaps, even more accurate.

164

MAURICE G. MEHL

A long stick with a hole the size of a pencil bored at midlength
may be moved about in a plane formed by the edges of a frame
about the model and somewhat higher than the latter. The
pencil, if fitted closely, may be ^^set’^ at the proper distances
above the base of the model and the corresponding contours
traced.

Fig. 6. An apparatus for contouring models and illustrating the use of con-
tours. Constructed in the laboratories of the department of geology, Denison
University.

ADVANTAGES OF THE MODELS

Contrary to what might be expected, the models promote
speed of contouring the field data. The average data may be
modeled and contoured and the contours transferred to paper
or tracing cloth in less time than is usually required to puzzle
out the best interpretation after the ordinary manner.

The model has been found an excellent aid not only in visualiz-
ing the data for the geologist but in explaining the nature of the
configuration of the beds to those not familiar with contours.
As a sales argument, several oil companies have found the models
invaluable.

DETERMINING THE STRUCTURE OF BEDDED ROCKS 165

Aside from these advantages, the models have a distinct phase
of usefulness. It is recognized by all geologists that some of the
data are at times more or less questionable. It is sometimes im-
possible to determine in the field whether beds have been prop-
erly correlated or whether an outcrop shows the true structural
attitude. When the structural data of a region are modeled
indiscriminately, it is not uncommonly found that certain of the
observation points are decidedly out of harmony with those
nearby. In other cases there is evident a distinct offset in the
surface represented by adjacent sets of observations. It is at
once suggested that the elevations of the adjacent regions have
been taken on different beds, beds that have been correlated as
the same, or the offset may be of such a nature as to be highly
suggestive of a fault which was not recognized in the field.
In this manner then, the modeling offers a further check on the
field valuation of the observation points.

Of special benefit are these suggestions in the interpretation of
well-log data. One recognizes the difficulty of interpretation of
such data because of the personal equation injected into the record
by the driller. His record, if not actually compiled from memory
at the end of his tower, is based on the hardness of the materials
as indicated by the difficulty of drilling, the color of the sludge
and, very rarely, the actual examination of the cuttings. Any
fall of material in an ^^open hole’’ will modify his record materially
and his estimates of the thickness or depth of any formation
rarely fits well with the steel tape check.

An illustration of the manner in which the models may be
useful is found in checking the data given in connection with the
structural map of the Bothwell-Thamesville oil district of
Canada.2 This map, reproduced with slight modifications in
plate XX, shows a portion of the structure which has evidently
been contoured from well log data from which has been deter-
mined the varying elevation of the Delaware limestone. It is
clear that unless other data were available than those men-
tioned by its author, there are many phases of the map which

2 Williams, M. Y., Oil prospects of Southwestern Ontario, Canadian Dept.
Mines, Summary Kept., 1917, pt. E, plate 1.

166

MAURICE G. MEHL

can not be looked upon as securely established. True, the
author of the map has recognized this to some extent, as is indi-
cated by the many dashed contours. Still, there may be ques-
tions as to the correctness of interpretation of some of the data
in the more definite portions of the map such as the extremely
long, narrow syncline near the center of the plate. Apparently
there is but a single observation upon which this is based not-
withstanding the fact that it is decidedly out of keeping with the
regional structure.

There is another striking peculiarity in the manner after which
the contours follow the outlines of the ^^oil pools’’ in all their
sinuosity. One recognizes the commion tendency to interpret all
data so as to favor a suitable structure” about producing w^ells
and is inclined to wonder if this is another illustration. Cer-
tain it is that so extensive a coincidence of the outline of the oil
pools and the contours is out of the ordinary.

The data indicated in this map has been modeled in recogni-
tion of the intersecting triangular plane method and the resulting
contours are showm in red on plate XX.

In constructing the model all of those observations that w^ere
designated as uncertain” have been omitted because in one
case on the original map the elevation of the datum plane varies
over 40 feet from the observed uncertain” elevation. While it
cannot be asserted that the resulting contours accurately record
the structure of the region, there can be no question but that
they do show, with possible minor Variations, the most logical
interpretation of the data utilized if we are to assume that the
data are all valid. As a matter of fact, several of the observa-
tions appear decidedly out of harmony with the general atti-
tude of the beds and should call for the most strict investigation
in the field before adopted. One striking example is the single
elevation upon which the conspicuous, inclosed depression near
the east center of the map is based.

Now w^hile the possibility of eliminating questionable data has
been pointed out, it must be recognized that there is great danger
in this easy elimination. It must be done with the best dis-
crimination and only after the closest study and after the sug-

DETERMINING THE STRUCTURE OF BEDDED ROCKS 167

gestions have been carefully verified in the field. Otherwise,
obviously, there would be a very natural tendency to eliminate
all data which did not make for a structure corresponding to the
preconceived ideas of the worker. It may be added, however,
that on nearly all occasions where the models have seemed to
demand the rejection of certain data the further investigations in
the field have justified this elimination.

PLATE XX

Structural contour maps to illustrate the difference between the common
methods of interpretation of structural data and the use of models for this
purpose.

r

+0 ^

I

o

<»

V)

Bulletin Scientific Laboratories Denfson University Vol. XIX PLATE XX

MEHL: original CONTOUR MAP

SOME SUGGESTIONS FOR INDICATING DRILLING

OPERATIONS

MAURICE G. MEHL

No doubt it has occurred to all who make use of maps show-
ing drilling operations, that the symbols used for this purpose
are not entirely satisfactory. Mr. E. G. Woodruff recently
called attention to the advantages in the uniform use of sym-
bols in a paper entitled Notebook form and symbols for petro-
leum geologists. 1 A few illustrations will serve to emphasize the
need for improvement in the methods for describing petroleum
and gas development graphically.

4. b. c. d. e. f. g. h, L J, A

Fig. 1

There seems to be no agreement among geologists, drafts-
men, and others responsible for the symbols as to how a certain
feature, a gas well, for instance, shall be designated. Most state
geological surveys have designs of their own selection, and even
the geologist as an individual is sometimes partial to a set of
symbols that is distinctive rather than useful. Unfortunately,
there seems to be no assurance that a design, once having been
selected for a certain feature, will be used consistently by its
author. The accompanying designs (fig. 1) will give some idea of
the great variety in the symbols used for a single feature. As
the source from which these designs were compiled does not
include private reports, the list is in no manner complete.

Adding to the confusion is the common practice of using the
same design to describe many different features. The symbol

1 Economic Geology, vol. 14, no. 5, p. 424, 1919.

169

170

MAURICE G. MEHL

for a gas well, for instance (fig. 1, d), has been used in published
reports alone to indicate fully a dozen different conditions such
as ^^Gas well/’ Abandoned gas well/’ Water sand/’ ^^Oil
well spoiled/’ Stopped above sand/’ etc.

Any set of symbols, if it is to be universally adopted, must
satisfy certain strict requirements. Most of these qualifications
are obvious, but certain of the more important are reviewed
herewith.

SIMPLICITY OF DESIGN

Simplicity is undoubtedly one of the most important con-
siderations. In the first place, to be most useful, the symbols
must involve the fewest possible number of lines. A compli-
cated design will not permit the reduction that is often neces-
sary or desirable. When it is realized that there are occasion-

X ^ m A

d. b. c. d. e. f. g. h. i. J k.

Fig. 2

ally over one hundred wells within a square mile, and that it is
not uncommon for maps to be reproduced on a scale of one inch
to the mile or less, there can be no doubt but that many designs
in common use are not well fitted for all scales.

Even though the maps are reproduced on a sufficiently large
scale, the designs are often so complicated as to appear very
similar and are, therefore, readily confused in a cursory glance.
Designs that depend for their distinctness on the difference in
length of component lines or the addition of a ray to a many
rayed figure are not desirable. Clearness of design is closely
associated with the numbers of lines involved.

To obtain clearness of design some have adopted a set of
distinctive figures such as circles, squares, crosses, pentagons,
etc. While such figures stand out conspicuously for the most
part, they are far from mechanically simple. As a rule they
involve ^Trregular angles” and a large number of operations.

INDICATING DRILLING OPERATIONS

171

Distinctive, but mechanically complex, designs are shown in
figure 2. Any attempt to use these symbols on a large scale
requires a great amount of labor or reduces the drawing to
freehand work, which is, as a rule, quite unsatisfactory.

FLEXIBILITY

To be of greatest use, a map showing oil and gas development
must be kept up to date. In order that development which is
today designated as a location may be changed to an oil or gas
well or a dry hole when the test is completed and may be indi-
cated as an abandoned producer at a later time, each symbol
used must be such that by simple additions it may be changed
to any other design that might be required in the normal history
of the well.

LOGICAL DESIGNS

Any development map is likely to show a considerable number
of different features. In reality, however, the information con-
veyed comes under one of three large heads: producing wells,
nonproducing wells, and locations. Each of these types re-
quires a distinct symbol, and inasmuch as a producer is pre-
dominantly either oil or gas, a distinction must be made between
these two. The result is that four primary symbols form the
basis for all designs that may be required.

Very commonly a well produces both oil and gas. The sym-
bols for each must be such that they can be combined readily so
as to produce a single, self-explanatory figure. The addition of
half the symbol for a gas well to that of an oil well tells clearly
that the producer is predominantly an oil well but with an appre-
ciable amount of gas. Or again, the combination of the total
essentials of the oil and gas symbols should convey the infor-
mation that the oil and gas are equally divided in the well.

Nonproducing wells may be dry holes or abandoned producers.
The reasons for nonproduction may be of great variety, and it
is often desirable to record these reasons. It is important to
know, for instance, that oil in quantities too small to be recovered

172

MAURICE G. MEHL

with profit, has been struck. The essential idea is that the well
is a nonproducer, however, and the nonproduction symbol must
be utilized. The proper designation for such a condition is
logically half the symbol for an oil well plus the synbol for a
nonproducer.

A dry hole is logically a combination of the symbols for a loca-
tion and nonproduction. It is true that many other details
concerning a dry hole are interesting and often important, such,
for instance, as the presence or absence of a sand, the nature of
the sand, the presence or absence of water, the adequacy of the
test, etc. It is very doubtful, however, whether such details
should be recorded on a development map except in the most
special cases. As a rule the map is a compilation from many
sources and not the record of the compiler’s direct observation
of the drilling. To be of real value, the statement that a certain
dry hole does not mark an adequate test, reasons for this con-
clusion are necessary. Apparently a written explanation is more
desirable than a special symbol for many of the details concern-
ing a nonproducing well.

Location” usually means actual drilling or good evidence
that drilling will be started soon — the erection of a drilling rig,
for instance. Very often a map is well marked with ^docations”
which are to be construed as meaning that they will become drill-
ing locations in the ordinary sense if the drilling well” proves
profitable, if more stock is sold, or if the fancy of the operator
does not change; very indefinite locations at best, and usually
calculated to mislead the uninformed. If it is desirable to dis-
tinguish between actual drilling locations and prospective tests,
it is probably well to use a definite symbol for a drilling well
and portions of the same symbol to designate the varying de-
grees of probability that drilling will be carried on seriously at
a later time.

THE UNI-COLOR SYSTEM

A great variety of simple symbols is to be had by the use of
colors and in many cases a multi-color scheme is employed to
good advantage. In most ^^pin systems” for keeping a record

INDICATING DRILLING OPERATIONS

173

of development on wall maps, pins with heads of various colors
show in a striking manner the trends of production. It is clear,
however, that for a set of utility symbols a multi-color system
cannot be used successfully, because the cost is in many cases
prohibitive, and because in the common reproduction by blue-
printing or photography, only black and white symbols may be
utilized.

Location.

O Inadequate. Test.

0

Dry Hole.

0

Show of OH.

0

Oil Well.

9 The Same- Abandoned.

0

Show of Gas.

Gas. IVe/l.

~^^The Same -Abandoned.

Oil Well with ShowofQds

The Same - Abandoned.

Oil and Gas Well.

-^The Same - Abandoned.

Gas Well with Show of Oil.

The Same -Abandoned.

Fig. 3

THE SUGGESTED SYMBOLS

In figure 3 is suggested a set of symbols thought to fulfil ade-
quately the requirements as outlined above. There is no rad-
ical departure from the present practice, for most, if not all, of
symbols are in common use. In one instance, the symbol for
a gas well, it has been necessary to alter a generally accepted
design. However, inasmuch as the essentials of the design are
the same and certain complications are avoided, the change should

174

MAURICE G. MEHL

not be annoying. Especially is this true in that the substitute
design requires fewer operations. All are mechanically simple
and require but a few operations. They are in a very real sense
self-explanatory and logical, and are of such a nature as to be
reproduced readily on either large or small scale.

The Inadequate Test’’ symbol of figure 3 illustrates the type
of variation from the generalized ^^dry hole” symbol which per-
mits the indication of a large number of details. By the sub-
stitution of such letters as W, C, and N, details like water
sand,” close sand,” ^^no sand,” etc., are recorded. Regardless
of the detail indicated by the letter, the essentials are the same —
a nonproducing well in which neither oil nor gas was encountered
in appreciable quantities.

Frequently it is desired to distinguish between wells producing
at different horizons. It has been the writer’s experience that
this and similar data can be shown with less confusion by placing
a Roman or an Arabic reference numeral against the regular
symbol than by the use of special designs such as have been
suggested.

THE KIMMSWICK AND PLATTIN LIMESTONES OF
NORTHEASTERN MISSOURI

AUG. F. FOERSTE

1. THE TERMS PLATTIN AND KIMMSWICK AS USED IN THE GEOLOGY

OF MISSOURI

The Champlainian or Alohawkian strata of Missouri may be
divided into two major lithologic divisions: a lower very fine
grained limestone in which usually no individual grains can be
recognized even with the assistance of a lens, and an upper, dis-
tinctly granular limestone which at some horizons is even coarsely
granular, and more or less crystalline.

In the Geology of Missouri, published by Prof. E. B. Branson
in 1918 as number 15 of volume 19 of the University of Missouri
Bulletin, the lower fine grained limestone is identified as the
Plattin formation, while the overlying distinctly granular lime-
stone is identified as the Kimmswick limestone, both names
being applied in a much less restricted sense than that advocated
at present by E. 0. Ulrich, the original author of these names.
This will become evident on referring to plate 2 among the Cor-
relation Tables at the close of Bassler’s Bibliographic Index of
American Ordovician and Silurian Fossils, published in 1915; a
part of this table is reproduced in a modified form on one of the
following pages in section 6 of this paper.

2. THE LITHOLOGICAL CHARACTERISTICS OF THE PLATTIN AND

KIMMSWICK LIMESTONES

The lower or Plattin limestone appears to have originated as
a lime mud deposited as the result of chemical action induced by
bacteria. During the deposition of these lime muds quiet waters
evidently prevailed. This is shown by the frequent preserva-
tion of even the most minute details of surface sculpture on brach-

175

176

AUG. F. FOERSTE

iopods, trilobites, and other fossils, and by the frequency with
which free cheeks are found still attached to the cranidia of trilo-
bites, even the thoracic segments sometimes being present. There
is no evidence in these strata of shells having been swept by cur-
rents into unnatural positions. There is no evidence of material
distinctly of clastic origin. No ripple marks cross the surfaces
of the limestone layers, although there is no reason why small
ripple marks should not appear locally.

The upper or Kimmswick limestone evidently is chiefly of
clastic origin, and might be defined as a lime sand formed by
the comminuted remains of shells, bryozoans, and other organ-
isms, more or less altered by crystallization. In the more coarsely
granular layers, irregular bedding and cross bedding is not un-
common. Trilobite remains almost invariably are dismembered
and more or less broken. The more strongly comminuted or-
ganic remains form a matrix in which many other fossils are
imbedded. It is remarkable how frequently the surfaces of the
imbedded fossils are well preserved. It is evident that commi-
nution of organic remains into lime sand preceded the washing
of these sands over the imbedded fossils sufficiently to prevent
the surfaces of the latter from being strongly abraded. Periods
of comminution and of aggradation of lime sands may have
followed each other more or less alternately, or the particles
comminuted in one area may have been swept by currents into
other neighboring areas.

3. THE FOLLEY, BRYANT, AND MCCUNE LIMESTONES,

OF KEYES

The first attempt to classify the Champlainian or Mohawkian
strata of Missouri and to apply geographical names to their major
divisions was made by Prof. C. R. Keyes in 1898, in a paper
on Some Geological Formations of the Cap au Gres Uplift, pub-
lished by the Iowa Academy of Science. In this paper the term
Bryant limestone is used for the upper part of the limestone in-
cluded by Branson in his Plattin formation, and the term Folley
is used for the lower part of the same formation. The name

THE KIMMSWICK AND PLATTIN LIMESTONES

177

McCune was used for the upper or Kimmswick limestone, as
the latter term is used by Bralison in the same area.

The term Bryant limestone includes the very fine-grained light
blue, relatively thin-bedded, richly fossiliferous limestone, which
not only contains a Lowville fauna but also has a Lowville as-
pect lithologically. The type exposures are along Bryant Creek
.in the northeastern part of Lincoln County. The total thickness
of the Bryant limestone was estimated by Keyes as between
140 and 150 feet. Only the top of this Bryant limestone was
studied in Ralls County by the present writer.

The Folley limestone includes the underlying light yellow,
heavy, magnesian, poorly fossiliferous limestone. The type lo-
cality is Folley, also spelled Foley, a railroad station a short
distance north of Winfield, in the eastern part of Lincoln County,
where the limestone is exposed in the bluffs west of the Missis-
sippi River. The thickness of the Folley limestone was esti-
mated by Keyes as 65 feet, but later it was recognized that the
actual thickness is considerably greater. In Ralls County the
Folley limestone is exposed north of the bridge 2 miles northwest
of Frankford, on the pike to New London.

Keyes evidently intended to use the term McCune for all of
the distinctly granular limestone of Champlainian age occurring
above his Bryant limestone. This would make the term McCune
equivalent to Kimmswick in the broader sense in which the lat-
ter is used by Branson. The type locality is near McCune sta-
tion, about half way between Frankford and Bowling Green, in
the northwestern part of Pike County, the exposures occurring
on Peno Creek, directly west of town, where a long bluff lines the
eastern side of the creek. The abundance of Receptaculites oweni
associated with Hormotoma major suggests that the actual ex-
posure west of McCune station is limited to the lower part of
the upper half of the Kimmswick limestone of Branson, but
does not rise as high as the top of the latter. Keyes at first
assigned a thickness of only 25 feet to his McCune limestone, and
raised this later to 50 feet, but it is known now that the Kimms-
wick limestone of Branson reaches thicknesses varying from 100
to 125 feet at several points in Ralls County, the county immedi-
ately north of that in which the typical McCune outcrops occur.

178

AUG. F. FOERSTE

4. THE TERMS PLATTIN AND KIMMSWICK PROPOSED BY ULRICH

The terms Plattin and Kimmswick were introduced by E. O.
Ulrich, and made their first appearance on page 111 of the report
of the Missouri Bureau of Mines, 2nd series, volume 2, published
in 1904. Here it is stated that the term Kimmswick is proposed
for the crystalline limestone exposed at Graysboro, Cape Gir-
ardeau, Glen Park, and Kimmswick, and that the term Plattin
was to be used for the starta between the Kimmswick and the
so-called First Magnesian limestone farther down. Kimmswick is
near the northeastern corner of Jefferson County, about twenty
miles southwest of St. Louis; the type exposures extend from
Kimmswick 8 or 9 miles southward to Riverside. Plattin Cre ek
traverses the southeastern corner of the same county, and is
about 18 miles from Kimmswick.

5. THE AUBURN CHERT STUDIED BY BRANSON

In 1909, Prof. E. B. Branson made a special study of the fauna
of the chert occurring in the very fine-grained limestone in the
vicinity of Auburn, a village in the north-central part of Lincoln
County, about 6 miles south of its northern boundary, and prob-
ably about the same distance from the type exposures of the
Bryant limestone. Although apparently of about the same hor-
izon as the Bryant limestone, the fauna studied by Branson has
gone into literature as that of the Auburn chert.

6. CORRELATION TABLES

The terKLS McCune, Auburn, Bryant, and Folley were founded
on exposures in the northeastern counties of Missouri, in Pike
and Lincoln Counties. The terms Kimmswick and Plattin were
drawn from localities in the southeastern counties of the same
state, both in Jefferson County. In. Branson’s Geology of Mis-
souri the terms Kimmswick and Plattin have been extended so
as to cover also the exposures earlier defined as McCune, Bryant,
and Folley, in the northeastern counties of the state. Judging
from the Correlation Tables published in Bassler’s Index, Ulrich

THE KIMMSWICK AND PLATTIN LIMESTONES

179

and Bassler prefer to use the terms Kimmswick and Plattin in
a more restricted sense. A modification of a part of one of their
tables is presented here in the following form:

KENTUCKY

SOUTHEASTERN

MISSOURI

NORTHEASTERN

MISSOURI

MINNESOTA AND

NORTHERN IOWA

Branson’s geol.

OF MISSOURI

McCune

Stewartville

Kimmswick

Curdsville

Prosser

Prosser

Kimmswick

Clay shale

Auburn

Decorah

Plattin

Tyrone

Plattin

Bryant

Platteville

Oregon

Folley

The preceding table suggests that in Champlainian times north-
eastern Missouri formed part of the northern Mississippi valley
province, including Minnesota, Wisconsin, and northern Iowa.
While considerable lithological differences are noted in passing
from northern Iowa across a long gap into northeastern Mis-
souri, a considerable part of the northern fauna may be still
recognized as far south as northeastern Missouri. It is not cer-
tain, however, that the typical Kimmswick fauna of southeastern
Missouri passes across the gap in northern Warren and southern
Lincoln Counties into northeastern Missouri. This can be
determined only after it has been ascertained definitely what
are the characteristics of this fauna, not at Thebes but at
Kimmswick, the type locality. Bassler lists only 4 species from
the Kimmswick: Comar ocystites shumardi, C. ohconicus, Echinc-
sphaerites aurantium, and Eurydictya calhounensis. None of
these species is known at Kimmswick, and the first three are
regarded as belonging beneath the lowest strata exposed in the
Thebes section.

If in Champlainian times there was an east and west barrier
across the central part of Pike county in the area now traversed
by the Cap au Gres fault, such a separation of northern and
southern faunas might have been operative at various times and

180

AUG. F. FOERSTE

in varying degrees. It may be noted, for instance, that the char-
acteristic cystid. Comar ocystites shumardi (see 4 in Description of
species), described from the Kimmswick of Cape Girardeau, in
southeastern Missouri, was found by the writer also in the large
quarry northwest of West Kimmswick, 85 miles northwest of
Cape Girardeau, but the most diligent search failed to reveal this
fossil in Pike or Ralls County, in northeastern Missouri. More-
over in Bassler’s Index, Echinosphaerites aurantium is listed from
the Kimmswick of Missouri, presumably from Cape Girardeau
in the southeastern part of the state, but no trace of this fossil
has been found in the northeastern part of that state.

7. STUDIES OF ONLY ONE LOCAL AUBURN AND ONE LOCAL KIMMS-
WICK FAUNA PUBLISHED SO FAR

Unfortunately, only two studies of the Champlainian faunas
here under consideration have been published so far. The first
of these is a detailed study by Prof. E. B. Branson of the fauna
of the Auburn chert, as exposed along a road side east of the
village of Auburn, in the north central part of Lincoln County.
This study was published in 1909, in volume 18 of the Transac-
tions of the Academy of Science of St. Louis. The following
year, in 1910, Prof. T. E. Savage published a detailed study of
the stratigraphic succession of the faunal elements of the Kimms-
wick limestone as exposed along the Mississippi River, three-
fourths of a mile south of Thebes, in Illinois. This famous lo-
cality is only about 6 or 7 miles southeast of Cape Girardeau, on
the Missouri side of the Mississippi River. Both of these studies
are confined to single formations as exposed at single localities.
No corresponding faunal studies have been published of the
McCune, Prosser, Plattin, Bryant, or Folley limestones of Mis-
souri or of the adjacent parts of Illinois.

THE KIMMSWICK AND PLATTIN LIMESTONES

181

8. RECENT STUDIES OF CHAMPLAINIAN FAUNAS IN NORTHEASTERN

MISSOURI

Recently the writer took advantage of an opportunity to study
in more or less detail several horizons among the Champlainian
rocks of Ralls County and of the adjacent parts of Pike County,
Missouri. These horizons included all of those included by
Branson under the term Kimmswick, used in the broader sense.
In addition, only the top of the underlying Plattin limestone was
studied with any care. No fossils were found in the overlying
Buffalo or Maquoketa clay shales in those parts of Ralls County
where these shales were present. At most localities in this
county, the Kimmswick of Branson is overlaid directly by the
Devonian. Farther southward, in Pike County, the Maquoketa
is sparsely fossiliferous.

In the area under investigation, the Champlainian strata are
exposed along the Salt River and its tributaries. Since interest
was centered chiefly on the Kimmswick limestone, using this
term in its broader sense, this limestone will be discussed first.

9. THE FAUNA OF THE KIMMSWICK LIMESTONE, SOUTH OF THEBES,

ILLINOIS

About three miles south of Thebes, Illinois, there is a conspic-
uous exposure of crystalline limestone along the east bank of
the Mississippi River. The fossils listed by Professor Savage from
this locality are recorded in the accompanying table. Section a
begins at water level, and section o occupies the highest position
stratigraphically. The thickness of the different parts of the
section is recorded in the table in feet and inches. A total thick-
ness of almost 70 feet of strata is exposed. Of this thickness the
lower 20 feet includes the more fossiliferous portion, to which
the overlying 50 feet apparently does not contribute any new
important faunal element.

It will be noted that neither Comar ocystites nor Echinosphaer-
ites are listed by Savage from this Thebes locality, although
both occur at Cape Girardeau, and Comar ocystites has been found
as far north as the large quarry northwest of West Kimmswick.

182

AUG. F. FOEKSTE

This suggests that the Kimmswick south of Thebes and the
Kimmswick at Cape Girardeau and at West Kimmswick may
not be identical stratigraphically.

The fossils listed in the last column of the table, under the
letters LR, were obtained on Little Rock Island, northwest of
Thebes, and evidently contain about the same fauna as the lower
strata examined by Savage at the locality south of Thebes.

10. KIMMSWICK FAUNA IN BALLS COUNTY AND IN NORTHERN PIKE

COUNTY, MISSOURI

The exposures at the Henry Hamilton, Big Cave, and Wood
Cave localities are in direct contact with the top of the Plattin,
and represent the lowest Kimmswick exposed in the Salt River
area. The lowest exposure along the Sanders branch, locality 1,
is supposed to begin about 15 feet above the base of the Kimms-
wick. Locality 7 forms the top of the section. The rise of the
stream channel is at a rate so small that no exact measurements
can be made readily and those here furnished, beneath the
locality numbers, are mere estimates.

A comparison of the lower part of the Sanders branch section,
including localities 1, 2, 3, and 4, with the Kimmswick limestone
section south of Thebes, Illinois, shows a considerable similarity
of faunas, including such forms as CUtambonites sp., Dinorthis
meedsi, Dinorthis pectinella, Parastrophia hemiplicata var., Am-
philichas cucullus, Ceraurinus cf. scofieldi or trentonensis, and
Remopleurides sp. With this lower part of the Sanders branch
section it seems possible to correlate also the Frankford and W.
T. Jackson localities, in the northern part of Pike County, owing
to the presence of Dinorthis meedsi and Amphilichas cucullus at
the latter localities.

Very little is known of the fauna of localities 5 and 6 of the
Sanders Creek section, beyond the fact that Hormotoma (?) major
tends to be more common here, and that various poorly preserved
species of Maclurina, Maclurites, and large forms of Fusispira
occur here. The limestone at this horizon tends to be more
coarsely granular and more crystalline than at other horizons in

THE KIMMSWICK AND PLATTIN LIMESTONES

183

the so-called Kimmswick section of Ralls County. The localities
at Sugar Creek and at McCune Station, in northern Pike County,
evidently belong to the same Hormotoma (?) major horizon. This
Hormotoma major zone is the McCune of Keyes, when this term
is used in a restricted sense.

The top of the so-called Kimmswick limestone section along
Sanders branch is formed by a finer grained limestone containing
an occasional poorly preserved Madurina and other fossils known
also in the underlying strata. It is overlaid by 5 feet of yellow-
ish clay, followed by 10 feet of fine grained Devonian limestone,
an unexposed interval of 7 feet, 6 feet of Devonian sandstone,
and a considerable thickness of fine grained Devonian limestone,
of which only the lower part is exposed at the locality in question.

At the W. H. Bowles locality, only the top of the Kimmswick
is exposed, overlaid by 2 feet of yellowish clay shale, 15 feet of
calcareous shale, probably Devonian, and 15 feet of undoubted
Devonian limestone. The chief interest at this locality was the
presence of a small Cydocystoides near the top of the Kimms-
wick limestone.

At Hagan’s shop, also at three-fourths of a mile east of Shiel,
and at a locality a mile northeast of Spalding Springs, all three
localities being located along the northwestern line of outcrop of
the so-called Kimmswick in Ralls County, Missouri, Pledam-
honites gibbosus occurs in the upper part of the Kimmswick sec-
tion. The Pledambonites gibbosus horizon is regarded as above
that of the typical Hormotoma (?) major zone.

11. CORRELATION OF RALLS AND PIKE COUNTY KIMMSWICK WITH

STRATA ELSEWHERE

It has been noted already, on a preceding page, that the strata
forming the lower half of the so-called Kimmswick section along
Sanders branch may be correlated with those strata south of
Thebes, Illinois, which were regarded by Savage as of Kimmswick
age. A considerable part of the fossils in these strata occur also
in the Prosser of Minnesota, although this may not involve,
actual identity of horizons.

184

AUG. F. FOERSTE

As far as known, the overlying strata, forming the upper part
of the Kimmswick section along Sanders branch, including both
the Hormotoma (?) major and the Plectamhonites gihhosus zone,
are not known to occur south of Pike County. Apparently they
are restricted to areas north of the Cap au Gres fault, and have
their affinities with the Prosser strata exposed in Minnesota. If
Plectamhonites gihhosus and Cyclospira hisulcata are to be re-
garded as characteristic of the lower half of the Fusispira bed
of Ulrich, then the highest so-called Kimmswick strata exposed
in Ralls County and in the adjacent parts of Pike County do not
rise above the Prosser horizons. This view is favored by the
extreme poverty of Maclurites and Maclurina in the upper strata
of the so-called Kimmswick in Ralls and Pike Counties.

Since the McCune exposures belong to the Hormotoma (?)
major zone, beneath the Plectamhonites gihhosus horizon, it ap-
pears necessary to correlate the McCune limestone also with the
Prosser of the Minnesota section, at least for the present. When
a better knowledge of the fauna of the McCune limestone has
been secured it may be necessary to alter this correlation.

On the other hand, the lower Kimmswick fauna, containing
Comarocystites and Echinosphaerites, is unknown in Ralls and
Pike Counties, in the northeastern part of Missouri. Until this
lower Kimmswick fauna is known in greater detail, it must be
regarded as practically an uncertain quantity in Champlainian
stratigraphy. At present it is assumed to belong below any strata
exposed at the locality south of Thebes, Illinois.

12. THE FAUNA OF THE PLATTIN LIMESTONE IN RALLS COUNTY,

MISSOURI

No fauna has been listed so far from the typical Plattin limestone
of southeastern Missouri. In the northeastern part of Missouri,
in Ralls County, only those fossils have been studied which occur
in the upper part of the Plattin limestone as there exposed, usually
within 10 feet of the top of the formation. On comparing the
fauna from the top of the Plattin limestone in Ralls County
with that of the Auburn chert in Lincoln County, enough differ-

THE KIMMSWICK AND PLATTIN LIMESTONES

185

trices are shown to suggest that they may belong to different
horizons. Of the new species and varieties described by Bran-
son from the Auburn chert, only Parallelodus oUiquus and Pter-
ygometopus Uncolnensis have been identified more or less doubt-
fully from the Plattin of Ralls County.

Faunal lists

In the accompanying faunal lists all that is known at present
of the faunas of the Kimmswick limestone south of Thebes, in
Illinois and in Ralls and Pike Counties, in northeastern Missouri,
has been tabulated in order to show the similarity of the Thebes
fauna to the fauna of the lower part of the Ralls County section.
On the other hand the fauna of the top of the Plattin limestone
in Ralls County and that from the Auburn chert has been tabu-
lated in order to make evident certain differences in faunal
content.

In the list of fossils from Thebes, the thickness of the strata
is indicated in feet and inches; in the list of fossils from Sanders
branch, the estimates are in feet. In the Sanders Branch sec-
tion, horizons 1 to 4 correspond to horizons a to f in the Thebes
section. Horizons j to o of the Thebes section contain about
the same fauna as the underlying horizons of this section. The
column marked L. R. records the species found on Little Rock
Island, which is located about 2 miles north of Thebes. Hori-
zons 5 and 6 of the Sanders Branch section form the McCune
zone of the Kimmswick and are not represented in the Thebes
section. In table 14, exposures corresponding to the lower
half of the Sanders Branch section are printed on the left side
of the Sanders Branch section, while exposures corresponding
to the upper half of the latter are printed on the right. The
Pike county sections are separated from the Ralls county sec-
tions by a darker line.

The numbers preceding the names of some of the fossils in the
various lists indicate the order in which these fossils are discussed
in the Description of Species, at the end of this paper.

186

AUG. F. FOERSTE

13. FAUNA OF KIMMSWICK LIMESTONE, THREE-FOURTHS MILE
SOUTH OF THEBES, ILLINOIS

CD

3

(M

A

3

1 (c) 2-0 1

CO

2

(e) 1-9

s

T

3

t

g

o

CD

00

g

5

?

?

1

3

(o) 15-0 1

(l r) 12-0 1

Receptaculites oweni

X

X

X

X

Clitambonites sp

X

X

Crania trentonensis

X

X

Crania cf. setigera

X

X

Dalmanella rogata.

X

X

X

X

X

X

X

X

X

X

X

X

Dinorthis pectinella

X

X

X

X

X

Dinorthis sp

X

X

X

X

X

X

X

Parastrophia hemiplicata

X

X

X

X

P. hemiplicata var

X

Platystrophia shepardi

X

X

X

X

X

X

X

X

X

X

X

Plectambonites minnesotensis

X

Plectorthis plicatella

X

X

Rafinesquina alternata

X

X

X

X

X

X

X

X

X

X

X

X

X

Rafinesquina minnesotense

X

X

Rhynchotrema anticostiense

X

X

Rhynchotrema increbescens

X

X

X

X

Scenidium anthonense

X

Schizambon sp

X

Strophomena billingsi

X

Str. emaciata

X

X

Str. scofieldi

X

X

Str. trentonensis

X

X

X

X

X

Triplecia sp

X

X

X

X

X

Zygospira recurvirostra

X

X

X

X

Cyclonema praeciptum

X

Cyrtolites ornatus var

X

Holopea pyrene

X

Strophostylus textilis

X

Ambony cilia amygdalina

X

Byssonychia intermedia

Orthoceras sp

X

X

X

X

X

X

Bronteus lunatus

X

X

X

X

Bumastus orbicaudatus

X

Bumastus trentonensis

X

X

X

X

X

X

X

X

Calymene callicephala

X

Ceraurus pleurexanthemus

X

Ceraurinus cf. scofieldi

X

Illaenus americanus

X

X

X

X

X

X

X

X

X

X

Isotelus maximus

X

X

X

X

X

Lichas

X

Amphilichas cucullus

X

X

X

X

X

X

Amphilichas cf. robbinsi

X

Pseudosphaerexochus cf. vulcanus

X

Pterygometopus intermedins

X

X

Remopleurides striatulus.

X

Remopleurides cf. canadensis

X

Thaleops cf. ovatus

X

THE KIMMSWICK AND PLATTIN LIMESTONES

187

14. FAUNA OF KIMMSWICK LIMESTONE IN RALLS AND NORTHERN
PIKE COUNTIES, MISSOURI

Receptaculites oweni

Streptelasma corniculum

Cyclocystoides cf. halli

Chasmatopora cf. reticulata. .

Constellaria varia.

Rhinidictya mutabilis

5. Clitambonites sp

Cyclospira bisulcata

Dalmanella rogata

Dinorthis meedsi

Dinorthis meedsi germana. . . .
Dinorthis pectinella.

7. Parastrophia hemiplicata var.

8. Platystrophia shepardi

Platystrophia trentonensis

Plectambonites gibbosus

Plectamborites minnesotensis
Rafinesquina alternata

10. Rafinesquina deltoidea

Rhynchotrema increbescens.. .
Strophomena incurvata

13. Strophomena cf. incurvata

Strophomena trentonensis. . . .

Strophomena trilobita

Ctenodonta intermedia

Vanuxemia hayniana

Fusispira nobilis

22. Hormotoma (?) major

23. Maclurina manitobensis.

24. Maclurites sp

Platyceras cf. depressum

Trochonema umbilicatum. . ; . .

Actinoceras cf. distans

Endoceras proteiforme

Spyroceras bilineatum

Tripteroceras cf. planocon-

vexum

32. Amphilichas cucullus

33. Bumastus cf. billingsi

34. Bumastus rowleyi nov. sp . . . .

35. Ceraurinus cf. trentonensis...

36. Ceraurus cf. bispinosus

Illaenus americanus

40. Proetus cf. undulostriatus

Pterygometopus callicephalus.

42. Remopleurides missouriensis .

05

1

P

pH

z

p

o

o

SANDEKS BRANCH

s

«

OQ

o

1

p

o

o

o

a

LOCALITIES

z

p

w

p

p

M

M

0^

1

K,

z

o

o

s

;>

o

m

o

s

3

QQ

<

p

05

b

p

M

p

w

«

O

M

o

<

w

M

0

o

c

1

2

3

4

5

6

7

o

n

05

w

o

o

K

»

o

M

<

a

K

u

2

S

6

w

15

25

10

30

25

15

10

W. H. I

<

o

■<

w

e4

3

COM

1 MI. N.

«

<

o

p

05

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

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

188

AUG. F. FOERSTE

15. FAUNA OF TOP OF PLATTIN LIMESTONE IN RALLS COUNTY

HENRY HAMILTON

YEAGER

CITY QUARRY

SUSAN KENNEY

BUFORD CAVE

J. H. SMITH

conn’s ford

BIG CREEK

NORTH OF SPALDING SPRINGS

ALSO IN AUBURN CHERT

Streptelasma breve

X

1. Tetradium fibratum

X

X

X

3. Cornulites fiexuosus

X

X

X

Orthis tricenaria

X

X

X

X

X

X

Pionodema subaequata

X

X

X

X

X

, X

X

X

X

Plectambonites sericeus

X

X

X

X

X

9. Zygospira nicolleti

X

X

X

Rafinesquina alternata

X

X

Rhynchotrema minnesotense..

X

12. Schizocrania filosa

X

X

X

Strophomena incurvata

X

X

X

X

X

X

X

X

14. Trematis huronensis

X

X

X

15. Zygospira deflecta

X

X

16. Ctenodonta cf gibberula

X

Ctenodonta nasuta

X

X

Ctenodonta nasuta robusta. . .

X

X

Ctenodonta cf. scofieldi

X

Cyrtodonta billingsi

X

X

Cyrtodonta huronensis

X

X

Cyrtodopta obesa

X

17. Parallelodus obliqua

X

X

Clathrospira subconica

X

X

X

18. Cyrtolites ornatus minor

X

X

Cyrtolites retrorsus var

X

X

Gyronema duplicatum

X

Helicotoma planulata

X

X

^x

19. Holopea concinnula

X

20. Holopea cf. parvula

X

X

21. Hormotoma gracilis angustata

X

X

X

X

X

X

X

X

X

Liospira obtusa

X

X

X

X

X

X

Lophospira bicincta

X

X

Lophospira obliqua

X

X

Lophospira oweni

X

X

X

Phragmolites fimbriatus

X

X

X

Salpingostoma buelli

X

Subulites conradi

X

25. Conularia heymani sp. nov.. .

X

26. Conularia sp

X

X

27. Hyolithes baconi

X

X

29. Orthoceras sp

X

30. Spyroceras bilineatum

X

X

X

X

X

X

31. Tripteroceras planodorsatum.

X

X

43. Bathyurus spiniger

X

X

X

X

Bumastus milleri

X

X

X

37. Ceraurus plattinensis

X

X

X

X

X

Isotelus gigas

X

X

X

41. Pterygometopus lincolnensis.

X

Pterygometopus intermedius..

X

X

X

X

THE KIMMSWICK AND PLATTIN LIMESTONES

189

16. THE FAUNA OF THE AUBURN CHERT, IN LINCOLN COUNTY,

MISSOURI

The following is a list of the species occurring in the Auburn
chert, in the vicinity of Auburn, in Lincoln County, Missouri.
Almost all of the species mentioned were listed by Professor
Branson in his paper on the fauna of* this chert, published in
1909. To this have been added those species which in the body
of Bassler’s Bibliographic Index are cited from the same horizon
and locality; and also a few species found by the writer in the
quarry a short distance north of Auburn, on the east side of the
main pike. Those found in this quarry are italicized. The new

species described by Branson

Hindia parva
Columnaria halli
Lichenaria typa
Streptelasma corniculum
2. Beatricea gracilis

Dalmanella testudinaria
Orthis tricenaria
Pianodema subaequata
Rafinesquina minnesotensis
Strophomena incurvata
Zygospira nicolleti
Zygospira recurvirostris
Aristerella nitidula
Clionychia lamellosa

* Ctenodonta auburnensis

* Ctenodonta costata
Ctenodonta logani
Ctenodonta medialis
Ctenodonta nasuta
Ctenodonta oviformis
Cyrtodonta billingsi
Goniophora carinata
Modiolodon (?) gibbus

* Modiolodon subrhomboideus

* Modiolopsis expansa

* Parallelodus obliquus
Whiteavesia subcarinata
Archinacella patelliformis
Bellerophon capax
Bucania halli
Carinaropsis acuta
Carinaropsis phalera

* Cataschisma typa
Cyrtolites retrorsus fillmorensis

are indicated by *.

Eotomaria dryope

* Helicotoma missouriensis
Helicotoma planulata
Helicotoma tennesseensis
Holopea insignis

* Hormotoma fasciata
Hormotoma gracilis sublaxa

* Hormotoma latiangularis
Liospira micula
Liospira progne
Lophospira fillmorensis
Lophospira obliqua
Lophospira oweni
Lophospira perangulata
Lophospira saffordi
Lophospira spironema
Phragmolites fimbriatus
Strophostylus textilis
Trochonema umbilicatum
Pterotheca expansa
Orthoceras sociale
Spyroceras bilineatum
Tripteroceras planoconvexum
Zitteloceras billingsi
Bathyurus extans
Bathyurus spiniger
Bumastus milleri
Ceraurus pleurexanthemus
Isotelus gigas

Pterygometopus intermedius

* Pterygometopus lincolnensis
Leperditia fabulites

* Technophorus bellistriatus

190

AUG. F. FOERSTE

17. LOCATION OF THE FOSSIL LOCALITIES IN THE KIMMSWICK OF
RALLS AND PIKE COUNTIES, MISSOURI

Frankford; quarried bluff below the level of the railroad, in
the eastern part of the town. W. T. Jackson farm; from Frank-
ford miles north, then about 1 mile east to a bluff north of
the spring east of the farm house; in the southern part of section
24 in R 4 W, T 55 N. Henry Hamilton; 3| miles directly north
of Frankford, in the center of section 14, along the road north-
west of the house, east of the creek. Big Creek; immediately
north of the entrance of Newlon branch, on the W. G. Harvey
farm, in the western edge of section 29, in R 5 W, T 56 N. Cave
on H. C. Wood farm; from New London 1 mile west and then
almost I mile north, in the eastern part of section 2.

Sanders branch; in sections 28, 21, and 22, 5 miles northwest
of New London. The lowest exposure occurs on the E. E.
Priest farm, north of the junction of the two main branches of
the creek in section 28, and contains Dinorthis pectinella. North-
eastward, on the J. H. Luke farm, in the southeastern corner of
section 21, ReceptacuUtes oweni and Constellaria varia are found.
These two localities are listed under locality 1 of the accompany-
ing table; the included strata are estimated to have a thickness
of 15 feet and to be about 15 feet above the base of the Kimms-
wick. Locality 2 consists of a thin limestone layer, scarcely |
foot thick, full of fossils; it is exposed in the southwest corner of
section 22, a considerable distance down stream from the cliff
spring west of the home of J. W. Briscoe. This locality is esti-
mated as 10 feet above the top of locality 1 and 15 feet below
the level of the Briscoe spring. Locality 3 extends from the
Briscoe spring to the road crossing east of the home of John H.
Kirchner; its total thickness is estimated at 10 feet. Locality
4 extends from the Kirchner road crossing to the first natural
rock dam located on the western fork of Sanders branch on the
Kirchner farm, and is estimated at 30 feet. Locality 5 is located
at an elevation about 20 feet higher, and includes 5 feet of strata
on the M. S. Warren farm, in the northwest quarter of section
22, along a bluff exposure containing Hormotoma major associ-

THE KIMMSWICK AND PLATTIN LIMESTONES

191

ated with some form of Maclurites, but H or motoma major is
much more common in the immediately overlying strata. The
total thickness of strata here involved is 25 feet. The strata in
which Hormotoma major is abundant are well exposed at locality
6 on the W. Z. Zink farm, in the northeastern part of section 22.
The rock here often weathers into coarse grained slabs with
tortuous channels on top, and with more or less irregular cavities
along the exposed margins. This coarse grained limestone is 15
feet thick, and is overlaid at locality 7 by a fine grained, richly
fossiliferous limestone layer, about one foot thick, overlaid by
about 9 or 10 feet of similar fine grained rock, but with very
few fossils beyond a single siphuncle of Endoceras and several
specimens of Streptelasma corniculum. The Kimmswick lime-
stone is overlaid here by 5 feet of yellowish clay shale of unde-
termined age.

W. H. Bowles farm; 2 miles west of New London, on south
side of road, on east branch of Doe Run, about | mile above its
confluence with the main creek. Hagan’s blacksmith shop; 7
miles west of the Oakwood end of Hannibal, and then 3 miles
south, south of road crossing at south end of section 13 in range
6 west. Three-fourths mile east of Shiel, near junction of three
forks of main creek, in eastern edge of section 20. One mile
northeast of Spalding Springs, at locality reached by going J
mile northeast from Spalding Springs, and then turning off east-
ward along a second road, and continuing to the top of the hill
land.

Sugar Creek; from Frankford miles eastward on the pike to
Louisiana, to exposures along the southwestern branch of Sugar
Creek, south of the pike. McCune; from the railroad station
westward to Peno Creek, and then southward along the creek.

18. LOCATION OF FOSSIL LOCALITIES IN THE PLATTIN OF RALLS

COUNTY

Henry Hamilton; 3J miles directly north of Frankford, in
center of section 14, northwest of house. Yeager farm; 3 miles
northwest of Frankford, on east side of pike to New London, a

192

AUG. F. FOERSTE

short distance northwest of the house. City quarry; about 1
mile southeast of New London on one of the main roads crossing
Salt River. Susan Kenney farm; 1 mile north of New London, at
the top of the bluff northwest of the bridge crossing a southern
tributary of Salt River. Buford Cave; on the M. F. Meyer farm,

2 miles west of New London, and then | mile north to a point
where the road turns west, near the eastern margin of section 2.
J. H. Smith farm; on south side of Salt River, 1 mile northeast of
Conn’s Ford, near the western edge of section 27, in R 5 W, T
56 N. Conn’s Ford; in bed of Salt River, about 4 miles north-
west of New London, in northwestern corner of section 33, R
5 W, T 56 N. Big Creek; on the W. G. Harvey farm, about 1
mile northwest of Conn’s ford, in the western edge of section
29. Northwest of Spalding springs about 1 mile, at the southern
end of section 23 in R 6 W, T 56 N, southwest of the home of
H. W. Ogle.

19. UNCONFORMITIES AT TOP OF KIMMSWICK LIMESTONE OF RALLS

AND PIKE COUNTIES

In the central and western parts of Ralls County the so-called
Kimmswick limestone is overlaid directly by the Devonian.
This includes all localities west and northwest of New London.
In the eastern part of Ralls County, however, the Buffalo shales,
typically exposed along Buffalo Creek, in Pike County, intervene.
An excellent exposure of the Buffalo shales is found in the east-
ern part of section 29, about 3 miles northeast of New London,
and about miles east of Salt River Switch railroad station.
They are well exposed also south of the home of W. H. Benham,
on the head waters of the western branch of Peno Creek, about

3 miles south of Frankford, in the southern part of section 15.
Here the Buffalo shales are underlaid by coarse grained lime-
stone, 4 feet thick, containing an undescribed species of N ileus,
(See under section 39 in Description of Species). Another
excellent exposure of Buffalo shales occurs 3 miles east of Frank-
ford, on the road to Louisiana. Here a knob formed by the
shales contains a large Rhynchotrema (See under 11, Rhyncho-

THE KIMMSWICK AND PLATTIN LIMESTONES

193

trema rowleyi, in Description of Species) and a multiplicate form
of Dinorthis of the D. suhquadrata group. Further southward
and southeastward in Pike county the Buffalo shales are overlaid
by Silurian strata, so that the Devonian limestones rest on suc-
cessively lower strata on proceeding from southern Pike County
north and northwestward across Ralls County. The Buffalo
shales correspond approximately to the Maquoketa of Iowa.
The immediately overlying part of the Devonian limestone cor-
responds closely to the Wapsipinicon of the same state.

At the same time those upper parts of the Devonian limestone
section which contain Acervularia appear confined to the more
northwestern exposures of Ralls County, extending in a north-
easterly direction from Shiel across the central parts of R 6 W,
T 56 N. They correspond to the Cedar Valley limestone of Iowa.

The Edgewood formation of Pike and of the immediately ad-
jacent counties, of Silurian age, apparently was deposited in a
restrictied basin separated from the Silurian of Iowa by some
barrier. During the later Devonian, however, the seas of Pike
and Ralls Counties may have been connected with those of Iowa,
but a barrier extending across the southern part of Pike and the
adjacent parts of Lincoln County may have limited these seas
southward, cutting them off from the more southern Devonian
areas of Missouri.

20. REMNANTS OF EARLY ORDOVICIAN FAUNAS IN THE EARLY
SILURIAN OF MISSOURI

One of the most striking features of the Richmond group is the
recurrence of Trenton, Black River, and earlier types, frequently
after a long absence during the intermediate Eden and Mays-
ville strata. In the Fernvale member of the Richmond from
southern Illinois and in the adjacent part of Missouri, Hehertella
lineolata Savage belongs to the same generic division as the new
species described in this paper from the Kimmswick limestone of
southeastern Missouri as Mcewanella raymondi. In the Thebes
sandstone of southern Illinois, Conularia delicatula Savage be-
longs to a group of species known hitherto only from the Trenton
of New York {Conularia granulata and C. papillata), but in-

194

AUG. F. FOERSTE

eluding also the Conularia heymani described in this article from
the Plattin limestone of Missouri. The little trilobite Endym-
ionia heUatula Savage, described from southern Illinois and north-
eastern Missouri, apparently finds its nearest relative in the Cana-
dian Endymionia meeki Billings of Quebec and Newfoundland.

In a similar manner the Orchard Creek shale at the base of the
Alexandrian (Medinan) of southern Illinois and adjacent Mis-
souri contains such Ordovician elements as Cyclocystoides, Bys-
sonychia, Lyrodesma, Phragmolites, Isotelus, and Ceratopsis, The
Calymene duhia of Savage belongs to the same group as Calymene
christyi and Calymene platycephala, from the Richmond and Tren-
ton respectively, for which the writer recently proposed the
generic term Platycoryphe.

The association of such Ordovician types with others of Silu-
rian character suggests the proximity of southern Illinois and
southeastern Missouri, in early Silurian times, to areas in which
Ordovician types still thrived. The associated Silurian forms
evidently must have originated as some more distant source, and
must have entered the eastern Missouri areas only as migrants.

DESCRIPTION OF SPECIES

1. Tetradium fibratum Salford.

Most species of Tetradium of Black River age consist of more
or less dissociated groups of cells, while massive growths pre-
dominate in later strata.

At the top of the Plattin limestone, in Ralls County, a species
with more or less flattened massive growth occurs, but in com-
paratively few numbers. One specimen, found at Conn’s Ford,
consists of a circular corallum, 32 cm. in diameter, and 6 to 8
cm. thick. Along the exposed surface the corallites are arranged
in straight or curved rows which intersect each other at angles
varying from 80 to 90 degrees. Usually about 7 corallites occur
in a width of 5 mm., varying locally from 6 to 8 in the same dis-
tance. The corallites are more or less quadrate in cross-section,
single septa extending inward from the middle of each wall, and
almost or fully reaching the center of the corallites. Similar
specimens occur at the J. H. Smith and Yeager localities.

THE KIMMSWICK AND PLATTIN LIMESTONES

195

2. Beatricea gracilis Ulrich.

Plate XXIII, fig, 7

Stems 6 to 7 mm. in diameter, and several centimeters long,
characterized by the presence of granules connected by the char-
acteristic more or less anastomozing lines as in typical Beatricea.
Strongly convex septal lamellae occur at intervals and occupy
almost the entire width of the stems. In the Auburn limestone
at the quarry a short distance north of Auburn, in Lincoln
County. •

3. Cornulites flexuosus Hall.

Specimens closely resembling the type of Cornulites fiexuosus
(Pal. New York, vol. VII, Supplement, 1888, p. 18, pi. 115, fig.
41), from the Trenton of New York, occur on moderately convex
forms of Rafinesquina alternata, at the top of the Plattin lime-
stone in the city quarry, at the Henry Hamilton locality, and
elsewhere in Ralls County. Usually this species is not listed
from below the Trenton.

4. Comarosystites shumardi Meek and Worthen
Plate XXII, figs. 24 A, B

The type of Comar ocystites shumardi was described from the
Kimmswick limestone at Cape Girardeau, in the southeastern
part of Missouri. The specimens here figured came from the
top of the Kimmswick limestone exposure at the large quarry
about ^ mile northwest of West Kimmswick, in Jefferson County.
One specimen consists of a fragment of the theca, bordering on
the anal opening, and exposing the interior side. The plates,
from this point of view, present a stellate appearance, the rays
extending from the center of one plate to the center of one of
the immediately adjoining plates. On the sides of the stellate
rays the pores open in rows parallel with the crest of the rays.
Viewed along the suture planes, between the thecal plates, the
pores are elongated vertically and tend to form vertical series.
A second figured specimen consists of a single detached plate.

196

AUG. F. FOEESTE

Several additional specimens, consisting of a number of plates
still attached to each other, were found at the same horizon.

The Comar ocystites horizon is regarded as below the Kimms-
wick strata exposed at the locality south of Thebes, Illinois,
which were studied by Prof. T. E. Savage.

Comar ocystites punctatus, from the Trenton of the Ottawa
area, is remarkable for possessing pinuliferous free arms, with
plates arranged in uniserial order (Ottawa Naturalist, 30, 1916,
October, November, December numbers.) Uniserial recumbent
fixed arms occur in Amygdalocystites and Canadocystis. Such
uniserial arms seem to be characteristic of a restricted closely
related group of cystids. At one time, this uniserial arrange-
ment of arm plates was regarded by the writer as primitive.
However, it is difficult to maintain this opinion in view of the
fact that all early cystids whose arm structure is known have
the biserial arrangement. Gogia prolifica Walcott (Cambrian
Geology and Paleontology, IV, no. 3, 1917, p. 68), from the Lower
Cambrian of British Columbia, and E ocystites (?) longidactylus
Walcott, from the Middle Cambrian of Nevada have biserial
arms. This is true also of Macrocystella mariae from the Upper
Cambrian of Shropshire of England, and Lichenoides from the
Cambrian of Bohemia.

5. Clitambonites cf. diver sus Shaler
Plate XXIII, fig. 6

Only a single brachial valve of Clitambonites, exposing its in-
terior, was exposed in the Kimmswick limestone, in the lower
half of the Sanders Creek section, in Ralls County.

An excellent pedicel valve was collected by D. C. Barton from
the Kimmswick limestone at the Glencoe Lime and Cement Com-
pany quarry, at Alincke, in St. Louis County. In this specimen
the cardinal area rises 10 mm. above the hinge-line, the latter
being 19 mm. wide, and the maximum width of the valve being
24 mm. The cardinal area forms an angle of about 135 degrees
with the plane of contact of the two valves. It is regarded as
a new species, but more material will be necessary to differen-

THE KIMMSWICK AND PLATTIN LIMESTONES

197

tiate it from the Anticostian Richmond species with which this
form usually is identified. Specimen preserved at Harvard
University.

Mcewanella nov. gen.

Hehertella Uneolata was described by Savage (Illinois Academy of
Science, 1917, p. 267, pi. I, figs. 1, 2) from the Fernvale member
of the Richmond near Thebes, Illinois, and at Cape Girardeau,
Missouri. The same species was described by Eula Davis Mc-
Ewan as Platystrophia fernvalensis (Proc. U. S. Nat. Mus., 56,
1919, p. 428, pi. 50, figs. 1, 2, 3), from the Fernvale limestone at
the old quarry southeast of Regenhardt’s quarry, northwest of
Cape Girardeau, Missouri. This species begins at the beak as
a distinctly plicated shell, the plications being distinctly striated
longitudinally. Toward the anterior margin the plications be-
come indistinct but the longitudinal striations remain distinct.
The median part of the brachial valve is elevated into a fold, and
the corresponding part of the pedicel valve is* depressed into a
sinus.

The anomalous position of this species is indicated by its ref-
erence to Hehertella by one author, and to Platystrophia by a
second. By the present writer it is regarded as distinct from
both, the sharply defined radial striations being unknown in
typical Platystrophia, and the distinct plications of the earlier
stages of growth being unknown in Hehertella. The pedicel valves
of both Hehertella and Platystrophia have deep muscular impres-
sions, those of Platystrophia being deeper and narrower. In this
respect the species here under consideration resembles Platy-
strophia more closely.

Owing to the occurrence in the Kimmswick limestone of south-
eastern Missouri of a second species, closely resembling Heher-
tella Uneolata generically, the desirability of a separate generic
designation for species having this type of structure was increased.
Therefore, the name Mcewanella is proposed in honor of Miss
McEwan, the author of the recent detailed study of the genus
Platystrophia, cited above.

198

AUG. F. FOERSTE

6. Mcewanella raymondi sp. nov.

Plate XXIII, fig. 1

Only a single brachial valve known, 26 mm. wide at the hinge-
line, 20 mm. long, and with a convexity of 9 mm. Valve strongly
plicated, the crests of the two median plications being only 3 mm.
apart and elevated into a median fold which rises 3 mm. above
the bordering depressions. The anterior margin of the shell
curves backward 5 mm. along this fold, thus indicating the pres-
ence of an equally conspicuous sinus on the pedicel valve. On
each side of the median fold of the brachial valve there are five
lateral plications, of which the first two are conspicuous, the
third is of intermediate size, the fourth and fifth are low, and a
distance of about 1.5 mm. intervenes between the fifth plication
and the hinge-area. The elevation of the first and second pli-
cations is about one millimeter ,, and their crests are rather ab-
ruptly rounded. The entire surface is radiately striated. At a
distance of about 5 to 10 mm. back from the anterior margin
these striae frequently average about 4 in a width of 2 mm., but
nearer the anterior margin, where numerous concentric lines of
growth indicate gerontic conditions, the number of these striae
may increase to 6 in the same width. The finer details of surface
structure are not well preserved.

From the Kimmswick limestone in the Glencoe Lime and
Cement Company quarry at Mincke, in St. Louis County, Mis-
souri. Collected by D. C. Barton. Named in honor of Prof.
Percy E. Raymond of Harvard University, to whom I am in-
debted for the loan of this specimen.

7. Parastrophia hemiplicata var.

Plate XXI, fig. Jj.; plate XXII , fig. 4

Two valves found in the Kimmswick limestone at locality 4
on Sanders branch, in Ralls County, are referred to Parastrophia
because they present a median septum extending forward as far
as midlength of the valve, separating posteriorly into two slowly
diverging lamellae such as those forming the narrow spondylium

s

THE KIMMSWICK AND PLATTIN LIMESTONES

199

in Parastrophia. There is no indication of sinus or fold, the
specimens being small, but along the anterior margin there are
traces of short low folds.

8. Platystrophia shepardi Castelnau
Plate XXI, jig. 5

Platystrophia shepardi was figured by Castelnau (Essai Sys-
teme Silurien FAmerique Septentrionale, 1843, p. 42, pi. 14, fig.
15) from the magnesian limestone of the Menominee River, near
its entrance into Green Bay. According to the Geological Map
of Wisconsin, published in 1911, this exposure near Menominee
might correspond approximately to the Prosser limestone of
Minnesota.

The brachial valve here figured was found at locality 3 in the
Sanders branch section, in Ralls County, but it occurs also at
similar horizons at other localities in Ralls and Pike Counties.

Most specimens are less elongate along the hinge-line, resem-
bling Platystrophia trentonensis McEwan, from the Prosser of
Minnesota and Iowa.

9. Zygospira nicolleti Winchell and Schuchert
Plate XXIII, jig. 8A, B.

The largest specimen found so far is 4.6 mm. long, 4.3 mm. wide,
and has a total depth of 3.2 mm., the pedicel valve being slightly
more convex than the brachial one. The median part of the
pedicel valve is angularly arched, and from this median part
the sides slope strongly downward toward the lateral margins.
The general surface of the brachial valve is convex; anteriorly
the median part is depressed into a sinus. Found near the top
of the Plattin limestone at the Buford Cave, at the Yeager local-
ity, and elsewhere in Ralls County, Missouri.

This species is related generally to Zygospira. Externally
it resembles Protoceuga anticostiensis Twenhofel, from the Rich-
mond of Anticosti, in the broad anterior median sinus on the
brachial valve and in the keeled median convexity of the pedicel

200

AUG. F. FOERSTE

valve. In one specimen there is a slight tendency toward the
elevation of the anterior snlcus of the brachial valve along its
median line, and from this it is assumed that the anterior part
of the median elevation of the pedicel valve might be slightly de-
pressed along its median line, but neither tendency finds suffi-
cient expression in any of the specimens at hand to admit of
positive observation. Protozeuga sulcocarinata Savage, from the
Alexandrian (Medinan) of Illinois and Missouri, appears closely
related to the Anticosti form. The Plattin species, here under
consideration, is supposed to be identical with the Black River
species Zygospira nicolleti^ which was described originally under
Hallina.

10. Rafinesquina deltoidea Conrad
Plate XXI, figs. 2, 2; plate XXII, figs. 2, 3.

The small specimens of Rafinesquina, here identified as Rafin-
esquina deltoidea (fig. 3), are not distinctly deltoid in form, but
they correspond most nearly to the specimen figured by Hall and
Clarke under that name (Pal. New York, 8, pt. 1, 1892, pi. 9A,
figs. 1, 2), from the Trenton at Jacksonburg, New York. Most
of these specimens do not exceed 20 mm. in length, but are so
strongly convex as to indicate their full maturity. Abundant at
localities 3 and 4 in the Kimmswick limestone of the Sanders
Creek section.

A single valve (fig. 2) , from locality 4 of the same section, re-
sembles the specimen figured by Hall as Leptaena (= Rafines-
quina) deltoidea (Pal. New York, 1, 1847, pi. 31 A, fig. 3a), from
the Trenton limestone at Trenton Falls, New York. It is 28
mm. long, 27 mm. wide, and has a convexity of 9 mm.

Larger, and relatively less convex shells, such as those usually
identified as Rafinesquina alternata (Emmons), also occur at
locality 3 on Sanders branch. One specimen is 31 mm. long, 35
mm. wide, and has a convexity of 7 mm. ; in other specimens the
convexity is even less.

All specimens of Rafinesquina alternata from the Plattin lime-
stone of Ralls County are only moderately convex, the convexity
usually not exceeding 4 mm.

THE KIMMSWICK AND PLATTIN LIMESTONES

201

11. Rhynchotrema rowleyi sp. nov.

Plate XXIII, fig. 2 A-D

Shells of large size, occurring as separated valves with the
anterior margin more or less broken off. In the three best pre-
served pedicel valves, with lateral diameters of 28, 29, and 33
mm., the lengths are estimated at 27, 29, and 33 mm., and the
convexities at 8, 8, and 9.5 mm. respectively. Three plications
occupy the sinus of the pedicel valve, and five or six plications
occupy each side, leaving an unplicated space 5 or 6 mm. wide
between the last plication and the postero-lateral angle of the
valve. Four plications occupy the median fold of the brachial
valve, and four occur on each side, occasionally with a trace of
a fifth lateral plication. The plications are crossed at regular
intervals by conspicuous and rather coarse concentric striae, of
which five or six occur in a length of 5 mm. on the more central
parts of the valves and toward the beak. In addition to the
coarser striae, some valves show much finer concentric striae,
and the latter tend to dominate along the unplicated postero-
lateral parts of the valves and also along the anterior, more or
less gerontic part of the valves.

The interior of both valves is constructed as in Rhynchotrema
capax, but the muscle scars are more deeply impressed. Ad-
ductor scars impressed in the posterior part of the muscular
area, distinctly defined laterally, 3 mm. wide and almost 6mm.
long. The remainder of the muscular area is occupied by the
diductor scars which are crossed by more or less irregular radi-
ating lines. The posterior part of the diductor scars embraces
the adductor scars. The area occupied by the diductor scars is
deeply impressed postero-laterally and is fairly distinct even an-
teriorly; its width is II mm., and its length is 12 or 13 mm. The
pitted ovarian markings occupy the area between the deeply
impressed postero-lateral parts of the diductor scars and the
nearest lateral margins of the shell. The teeth project upward
and inward, and posterior to the teeth are distinct sockets for
articulation with the posterior part of the hinge plates on the
brachial valve.

202

AUG. F. FOERSTE

The cardinal process in the brachial valve consists of a very
narrow median vertical plate, on each side of which are the bases
supporting the crura. The crura project forward from near the
inner margins of these bases, and the surface of the latter tends
to be distinctly concave toward the cardinal process. The pos-
terior part of the bases articulates with the sockets posterior
to the teeth of the pedicel valve, and sockets for the reception
of these teeth occur exterior to the bases supporting the crura
in the brachial valve. The cardinal process and the adjacent
parts of the bases unite anteriorly and connect with the median
ridge which extends slightly more than half the length of the
valve forward. About 4 or 5 mm. in front of the cardinal proc-
ess there are more or less distinct lateral branches of the ridge,
evidently limiting the anterior from the posterior adductor scars.

From the Buffalo or Maquoketa shales 3 miles east of Frank-
ford, in Pike County, at a small knob on the north side of the
pike to Louisiana. Named in honor of Prof. R. R. Rowley of
Louisiana, who for many years has investigated the strata of
eastern Missouri. Characterized by its large size and by the
conspicuous and distant concentric striae.

12. Schizocrania filosa Hall

In the eastern part of the United States the earliest occurrence
of this species is in the Trenton. In Minnesota it occurs as low
as the Decorah shales. In Ralls County, Missouri, it is fairly
common at several localities near the top of the Plattin limestone;
among others, at Conn’s Ford, Buford Cave, and along the lower
part of Big Creek.

13. Strophomena cf. incurvata Shepard
Plate XXI, fig. 1 , plate XXII, fig. 1

A single specimen of Strophomena, 56 mm. wide along the hinge-
line, and 34 mm. long from the beak of the pedicel valve to its
margin, was found at locality 3 on Sanders branch, in Ralls
County, in the Kimmswick limestone. The concavity of the

THE KIMMSWICK AND PLATTIN LIMESTONES

203

pedicel valve is moderate, scarcely exceeding 2 mm. ; the convex-
ity of the brachial valve may not have exceeded 7 mm., as far
as may be judged from the part remaining. The hinge-area of
the pedicel valve is relatively high, equalling at least 3 mm. at
the beak. The angle between this cardinal area and the general
surface of the pedicel valve is about 15 degrees. The postero-
lateral angles equal about 70 degrees. The surface of the valves
is covered with radiating striae, 6 or 7 in a width of 2 mm. Every
fourth one of these striae tends to be slightly more prominent,
this tendency being greater in the brachial valve. The individ-
ual specimen here described is associated with numerous speci-
mens of typical Strophomena incurvata, and may be only an
aberrant form of the latter.

14. Trematis huronensis Billings

Outline circular, upper valve moderately convex, the convexity
increasing toward the beak. Largest specimen found is 25 mm.
in width and 22 mm. long. The surface is ornamented by radi-
ating and concentric striae, the intercepted areas being occupied
by small elliptical or more or less quadrangular pits. In some
specimens the striae and pits are distinctly perceptible as far as
the beak. In these specimens, both the radiating and the con-
centric striae tend to be narrow, and the intercepted pits tend
to be more quadrangular. In other specimens the pits diminish
more rapidly in size than the intermediate striae toward the
beak, finally appearing as minute circular pits arranged in rows
on an area which otherwise is smooth; sometimes the pits dis-
appear altogether before reaching the beak. In a third group
of specimens, the concentric striae are considerably narrower
than the radiating ones, at least posteriorly, and especially be-
tween 5 and 10 mm. from the beak. Anteriorly, in the more
mature stages of growth, the specimens are much alike; both the
radiating and concentric striae are narrow and the intercepted
pits are more or less quadrangular. In the mature stages of
growth the number of pits usually varies from 8 to 9 in a width of
2 mm., but in the final stages of growth this number may in-

204

AUG. F. FOERSTE

crease to 10 or 11 in the same distance. Occasional specimens
occur in which the number of pits at midlength of the shell, just
before reaching the point of intercalation of additional rows of
pits, may equal 7, or even 6 in a width of 2 mm. On closer
examination, the concentric striae are found to be not strictly
continuous. From 4 to 10 pits may form a continuous series
in a lateral direction; then there is a slight jog, beyond which
there is another continuous series of pits. Only a single specimen
was found in which the pits of adjacent concentric rows alter-
nated sufficiently to accord with the description and figure of
Trematis ottawaensis Billings (Palaeozoic Fossils, 1865, p. 53, fig.
58), from the Trenton limestone at Ottawa, Canada.

The specimens here described occur in the top of the Plattin
limestone at Conn^s Ford, Buford Cave, and at the Yeager
locality.

In Trematis punctostriata Hall, from the type horizon and
locality, in the Saltillo (Trenton) limestone at Clifton, Tennessee,
similar features are shown. Posteriorly the pits are small and
distant, on an otherwise smooth surface, disappearing before
reaching the beak. Anteriorly the pits are separated only by
narrow radiating and concentric striae. The number of pits
sometimes reaches 8 in a width of 2 mm. near midlength of the
shell, increasing to 10 and 12 in the same width along the an-
terior margin. The concentric arrangement of pits is continuous
for distances including 4 to 10 pits, beyond which there is a
slight jog, followed by another continuous series of pits. Alter-
nation of pits belonging to adjacent rows, as described in Tre-
matis ottawaensis, is confined to only three or four rows in those
few cases where it was detected at all.

15. Zygospira deflecta Hall
Plate XXII, figs. 5 A, B

Shells small, scarcely exceeding 3 mm. in length, character-
ized by a broad and distinct median depression on the brachial
valve, its entire width occupied by five radiating plications, the
total number of plications on the valve usually equalling 17 to

THE KIMMSWICK AND PLATTIN LIMESTONES

205

21. The median part of the pedicel valve, for a width of 4
radiating plications, is distinctly elevated above the rest of the
valve. Contrasted with the brachial valve, the pedicel valve
is considerably more convex.

Found at the top of the Plattin limestone, at Buford Cave, and
at the Yeager locality, in Balls County.

The specimens here described agree fairly well with those fig-
ured by Hall (plate XXII, figs. 5 A, B of this bulletin), from the
middle Trenton at Martinsburg, New York, as Atrypa (= Zygo-
spira) deflecta. Zygospira recurvirostris (Hall), from the same
locality and horizon, differs from Zygospira deflecta chiefly in
the greater convexity of the brachial valve and in the much
less conspicuous depression of the median part of this valve.
If it be possible to separate Zygospira recurvirostris from Zygo-
spira deflecta by means of these characteristics, then the Plattin
limestone specimens come nearer to Zygospira deflecta. If these
two species prove not distinct, then both must bear the name
Zygospira deflecta, since the original description of Zygospira de-
flecta precedes that of Zygospira recurvirostris in the original de-
scription of these species (Paleontology of New York, 1, 1847,
p. 140, pi. 33, figs. 4 a, b).

16. Ctenodonta of gibberula group.

Plate XXI, flg. 13

A single left valve of some species of Ctenodonta was found
near the top of the Plattin limestone, about 1 mile northwest of
Spalding Springs, near the home of H. W. Ogle. Compared
with Ctenodonta gibberula Salter (plate II, fig. 13 of this bulletin),
the shell is of smaller height, the ventral margin is much less
convex, the angle between the hinge areas anterior and posterior
to the beak is more divergent, and the entire aspect of the shell
is more elongate.

206

AUG. F. FOERSTE

17. Parallelodus obliqua Branson
Plate XXI j fig, I4

A distinct and rather angular umbonal ridge extends from the
beak toward the lower posterior angle. The post-umbonal slope
is distinctly concave, especially toward the beak. The remainder
of the valves, below and anterior to the umbonal ridge, is gently
and evenly convex. There is no trace of a mesial depression or
sinus. The ventral margin is gently and evenly convex for al-
most its entire length, rounding more abruptly upward at the
two extremities of the shell. The posterior margin of the shell
is strongly oblique to the hinge-line, producing a rather narrowly
rounded posterior angle. None of the specimens expose the
teeth. The general appearance is that of Modiolopsis, but the
absence of a mesial depression suggests the possibility of identity
with Parallelodus.

In Modiolopsis consimilis Ulrich (plate II, fig. 14, of this bul-
letin), the ventral margin is nearly straight and the slope between
this margin and the umbonal ridge is distinctly flattened.

18. Cyrtolites ornatus minor Ulrich and Scofield

Two forms of Cyrtolites occur near the top of the Plattin lime-
stone in Ralls County. The largest specimens reach a diameter
of fully 18 mm. Those specimens in which the transverse undu-
lations meet the carina almost at a right angle are referred to
Cyrtolites ornatus minor, while those in which the undulations
curve strongly backward are regarded as a variety of Cyrtolites
retrorsus Ulrich.

19. Holopea cf. concinnula Ulrich and Scofield
Plate XXI, fig. 7

A specimen found at the top of the Plattin limestone at Conn^s
Ford has about the same apical angle as typical Holopea concin-
nula (plate XXII, fig. 7 of this bulletin), but the shell is smaller
and the rate of enlargement of the volutions is less rapid. .

’ THE KIMMSWICK AND PLATTIN LIMESTONES

207

20. Holopea cf. parvula Ulrich
Plate XXI j jig, 6

A specimen of Holopea, 24 mm. in diameter, was found at the
top of the Plattin limestone at Conn’s Ford. In the elevation
of its spire and in the rate of enlargement of its last volution,
this specimen resembles the much smaller species Holopea parvula
(plate XXII, fig. 7, of this bulletin) , from the Flanagan member
of the Trenton of central Kentucky.

21. Hormotoma gracilis angustata Hall
Plate XXI, jig, 8

A species of Hormotoma is very abundant at every locality in
Ralls County, where the top of the Plattin limestone is exposed.
The specimens attain a larger size than those ordinarily referred
to Hormotoma gracilis angustata. Compared with Hormotoma
gracilis suhlaxa, from the Auburn of Lincoln County, the volu-
tions are less oblique.

22. Hormotoma (?) major Hall

This species is quite common in the coarsely granular or crys-
talline McCune limestone in Pike County; if the name McCune
be restricted to strata equivalent to the exposures found near
McCune station, then the species may be said to characterize
this division of the Kimmswick, using the latter term in the
broad sense employed by Branson. One of the Pike County
specimens was figured by Ulrich in the Paleontology of Minne-
sota, vol. Ill, pt. 2, 1897, on plate 71 (figs. 5, 6).

23. Maclurina manitobensis Whiteaves

A single specimen, 50 mm. wide, from the lower part of the
Hormotoma major or McCune zone, was found on Sanders branch,
in Ralls County. It is referred to Maclurina on account of the
small width of the umbilicus. While the shell is considerably

208

AUG. F. FOERSTE

smaller than mature specimens of Maclurina manitohensis, the
umbilicus apparently enlarged at the same rate and the keel
surrounding this umbilicus rises at about the same angle. In
Maclurina cuneata the keel rises much more rapidly, and the
umbilicus is much narrower.

24. Maclurites sp.

A single specimen, 50 mm. wide, from the Hormotoma major
zone on Sanders branch, is referred to Maclurites on account of
the relatively wide umbilicus. The specimen may be regarded
as a depressed form of Maclurites big shy i Hall, a Platteville
species found in Wisconsin and Minnesota, the shell being more
depressed even than figure 7 on plate 75 of the Paleontology of
Minnesota, III, part 2, 1897; moreover, the peripheral angle is
more acute and the umbilicus exposes fewer volutions. Com-
pared with Maclurites depressus Ulrich, from the Platteville of
Minnesota, the width of the umbilicus is similar, and the per-
ipheral angle is only moderately greater, but there is no tendency
toward concavity on the flattened side of the volutions. Com-
pared with Maclurites crassa, Ulrich and Scofield, and its variety
macra, the umbilicus is much smaller, and the peripheral angle
is more acutely rounded.

25. Conularia heymani sp. nov.

Plate XXI, fig. 12, plate XXII, fig. 12

Only one of the four faces of the shell is exposed and even of
this face the lateral margins are not distinctly defined. As far
as may be determined from the part exposed, the lateral margins
of the one face here described diverge at an angle of about 15
degrees. The median line of the face is occupied by a narrow
groove, on each side of which is a slightly raised line, light brown
in color, ^t the smaller end of the specimen the raised lines are
about 0.8 mm. apart; 20 mm. farther up they are about 1.25
mm. apart. Beyond this point they can not be measured accu-
rately. The face is crossed transversely by very fine striae which

THE KIMMSWICK AND PLATTIN LIMESTONES 209

rise from the lateral margins as far as the slightly raised lines on
each side of the median groove, forming an angle of about 75
degrees with these raised lines. Between these lines the trans-
verse lines curve so as to cross the median groove without any
interruption or abrupt change of direction.

The number of transverse striae varies from 6 to 9 in a length
of 1 mm. near the smaller end of the specimen and also farther
up, at midlength. At the larger end, where gerontic conditions
appear to have set in, the number of these transverse striae equals
11 to 12 in 1 mm. The transverse striae are very narrow, and
their crests are lined with minute granules, numbering from 11
to 17 in a distance of 1 mm. on various parts of the shell. The
granules are arranged also in vertical rows. The linear areas
between the transverse striae are depressed into broad and rather
shallow grooves. Along that margin of the grooves which is
nearer the apical end of the shell, very low granules appear, but
th se granules alternate in position with those on the transverse
striae and are visible only under a lens.

The transverse striae cross the pair of slightly raised vertical
lines along the median part of the face, as though these lines did
not exist. The raised lines appear to be due to features not on
the exterior but on ‘the interior of the shell. Along the raised
lines the interior of the shell appears to be thickened. In a
fossil state this thickened part tends to be preserved better
than the adjacent parts. Moreover, during fossilization it
tends to be lifted slightly above the adjacent parts. The
median groove appears to locate a line of weakness in the shell.
In cross-sections the raised lines are seen to be due to the
presence of a pair of very short longitudinal septa on the
median part of the inner side of each face of the shell.

Found at the top of the Plattin limestone at Conn’s Ford, four
miles northwest of New London, in Balls County. Named in
honor of A. W. Heyman, in memory of many days spent on
geological trips in Ohio and Missouri.

Conularia heymani differs from Conularia granulata Hall
(Pal. New York, 1, 1847, p. 223, pi. 59, figs. 5 a, b), from the
Trenton at Middleville, New York, in the absence of distinct
vertical striae connecting the vertical rows of granules.

210

AUG. F. FOERSTE

26. Conularia sp.

Plate XXI, fig. 9; plate XXII, fig. 9 A, B

Half a dozen fragments of some very thin-shelled Conularia,
rolled up into a more or less tubular form, were found within
the living chamber of some Orthoceroid shell. The fragments
are enrolled laterally. This is indicated by a narrow dark brown
line extending lengthwise down the enrolled fragments. The
width of this line is approximately | mm. Along this line the
inner side of the shell is supported by a narrow sharp septal
ridge, extending about i mm. from the wall of the shell inward.
This septal ridge is colored deep brown, and it is the color of this
ridge which is seen through the thin wall of the shell itself and
which forms the narrow dark brown line as seen on the exterior
of the shell. Possibly a minute tube may have run down the
interior of this septal ridge, close to the wall of the shell, but
this could not be determined beyond all doubt. In order to
conform with Conularia of the C. heymani type, a second brown-
ish line ought to extend down the tubular fragments, parallel to
the brownish line actually found, but in none of the fragments
was a second line found. However, since in no case a sufficient
width of surface was exposed on both sides of the brownish line
actually present, it is not possible to determine definitely either
the presence or absence of such a second parallel brownish line.
Judging from analogy with Conularia heymani, it is here assumed
that the second brownish line should occur in specimens showing
a sufficient width of the original shell wall.

The longest enrolled fragment is 26 mm. long, and the various
fragments are enrolled so as to produce the appearance of tubes
about 4 or 5 mm. in diameter. All of the so-called tubes are
more or less crushed and have their enrolled margins more or
less separated.

The surface is ornamented by minute granules, about a 0.05
mm. in diameter. These granules are arranged both in trans-
verse and in vertical rows. In the transverse rows 10 to 13
granules occupy a width of one millimeter, and in the vertical
rows usually about 8 granules occupy the same length, although

THE KIMMSWICK AND PLATTIN LIMESTONES

211

their number varies from 7 to 9, and 11 occasionally are found.
The transverse rows of granules tend to be supported by low
transverse wrinkles or striae, but the intermediate grooves
never are sharply defined and the wrinkles or striae often are
obsolete. In the latter case the granules appear arranged in
rectangularly intersecting rows on otherwise nearly smooth sur-
faces. On some fragments, numerous low parallel wrinkles
more or less connect the granules in a diagonal, not in a vertical,
direction, somewhat as in Conularia cayuga as figured by Hall
(Pal. New York, 5, pt. 2, 1879, pi. 34, fig. 5) from the Hamilton
group of New York.

From the city quarry, one mile southeast of New London, in
the upper part of the Plattin limestone.

27. Hyolithes baconi Whitfield
Plate XXI, figs. 10 A, B, 11; plate XXII, figs. 10, 11

Apical angle 20 degrees. Top of shell 9 mm. in width. Cross-
section somewhat triangular, with one side flattened and the
opposite side convex, the dorso-ventral diameter at the top of
the shell being 2.5 mm. in the shell here described. The small
size of this diameter may be due in part to compression. The
shell is striated transversely, the direction of these striae being
almost directly transverse on the convex side of the shell, while
on the flattened side they curve distinctly upward.

In one specimen (fig. II) the median part of the convex side is
slightly more convex than the lateral parts of this side, and is
separated from the latter on each side by a slightly concave
area. The lateral margins are narrowly rounded. Of the trans-
verse striae 14 occupy a length of 3 mm. at the larger end of
the shell, preceded by 15 in the same distance at midlength,
increasing still farther in number toward the apical end. The
transverse striae are crossed by much finer vertical striae, of
which 8 to 10 occur in a width of 1 mm.

Hyolithes haconi is fairly common at one horizon near the top
of the Plattin limestone, but most specimens do not show the
low median elevation on the convex side of the shell and the fine

212

AUG. F. FOERSTE

vertical striae rarely are shown. Possibly most specimens lack-
ing these vertical striae are casts of the interior of the shell.

Found at Buford Cave, 2 miles west of New London, near the
top of the Plattin limestone.

28. Hyolithes miseneri Foerste

Under, the name Conularia miseneri the writer described a
'series of specimens from the Whitewater member of the Rich-
mond at Richmond, Indiana (Journal of Cincinnati Soc. Nat.
Hist., 22, 1917, p. 42, pi. I, figs. 1 A, B, C). Later it was recog-
nized that the supposed Conularia was the convex side of a
species of Hyolithes, the median part of which was elevated as
in the second specimen of Hyolithes haconi, described in the pre-
ceding lines. The transverse striae are more prominent. Along
the median line of the shell they curve slightly downward;
laterally they curve rnore strongly downward as far as the lateral
sides of the shell where they begin to curve rapidly upward.
From this it is assumed that on the flattened side of the shell the
transverse striae curve strongly upward as in other species of
Hyolithes. The vertical striae are finer but distinct. An almost
identical species occurs in the Kimmswick of southern Missouri.

29. Orthoceras with vertical color bands.

In a specimen of an unknown species of Orthoceras found at
the top of the Plattin limestone at Conn’s Ford, vertical color
banding is present. The specimen is 22 mm. in width. The
color bands equal or slightly exceed 1 mm. in width and are
1 mm. or slightly less apart. The color banding is a feature
characteristic of the inner layers of the shell and is seen best
where the surface of the shell has weathered away.

Orthoceroid shells with vertical color bands are known also
at other horizons. In the Lorraine formation in the river bed
west of Weston, Ontario, vertical color bands occur in an Ortho-
ceroid shell 22 mm. wide, having a siphuncle with nearly spheri-
cal segments (Loxoceras ?). About 8 vertical color bands occur
in a width of 5 mm., the width of the color bands and that of the
intervals between being about the same.

THE KIMMSWICK AND PLATTIN LIMESTONES

213

In a similar species (Loxoceras .^)/from the Richmond forma-
tion at the Clay Cliffs on the eastern shore of Manitoulin Island,
the vertical color bands are about 1 mm. in width and are sepa-
rated by intervals varying from 1 to 2 mm. where the diameter
of the shell equals 15 mm.

In Orthoceras trusitum Clarke and Ruedemann, from the
Guelph at Rochester, New York, specimens occasionally show
color banding. In the specimen represented by figure 2 on
plate 13 of Memoir 5, New York State Museum, 1903, there are
9 or 10 vertical light brown bands in a width of 3 mm. In the
specimen represented by figure 9 the structure usually accom-
panying color banding is present, but there is no distinctive
color here. This structure consists in the space between the
color bands being composed of a less dense and more readily
weathering material than that forming the color bands.

In all cases of color banding observed by the writer the color
banding consisted of various tints of brown.

30. Spyroceras bilineatum Hall

In typical Spyroceras bilineatum, from the Trenton of New
York, the coarser vertical striae alternate with finer ones.
Conchs of this type occur at the top of the Plattin limestone at
Conn’s Ford, Buford Cave, and elsewhere in Ralls County.
They are accompanied by other specimens in which the vertical
striae practically are of uniform size. In one specimen 17 mm.
in diameter, these vertical striae number 12 or 13 in a width of
5 mm.

31. Tripteroceras cf. planoconvexum Hall

In the Hormotoma major zone 4^ miles east of Frankford, in
Pike County, south of the crossing of the pike to Louisiana
across the western branch of Sugar Creek, a species of Triptero-
ceras was found which is identical with the species figured by
Clarke from the Prosser limestone at Hader, Minnesota (Pal.
Minnesota, III, pt. 2, 1897, pi. 57, fig. 1). Compared with
typical Tripteroceras planoconvexum, from the vicinity of Beloit,
Wisconsin, however, the species here under consideration appears
larger, and with a smaller apical angle.

214

AIJG. F. FOERSTE

32. Amphilichas cucullus Meek and Worthen

This species was described from the Kimmswick limestone in
Alexander County, Illinois, presumably from the exposure south
of Thebes studied by Professor Savage. The same species is
common in the second quarter of the so-called Kimmswick lime-
stone of Ralls and Pike Counties, measuring upward from the
base. It is one of the most characteristic fossils of this horizon.
It is overlaid by the Hormotoma major or McCune zone.

33. Bumastus holei sp. nov.

Plate XXI j figs. 15 A, B; plate XXII, figs. 15 A, B

The cast of the lower side of the cranidium is characterized
by shallow impressed lunettes, relatively very distant from each
other, but rather close to the posterior margin. The length of
the cranidium is 25 mm.; its width is 30 mm.; the distance be-
tween the impressed lunettes is 18 mm. ; the length of the lunettes
is 5 mm., and their posterior margin is 5 mm. from the posterior
margin of the c anidium. The general convexity of the cranid-
ium from side to side is small.

The associated pygidium is 28 mm. wide, 19 mm. long, and
has a convexity corresponding to that of the cranidium. The
articulating axial part is 11 or 12 mm. in width, and from this
axial part the lateral articulating margins bend back at an
angle of at out 155 degrees.

Found at locality 3 in the Kimmswick limestone section on
Sanders branch. Probably identical with the species figured by
Clarke (Pal. Minnesota, III, pt. 2, 1897, p. 722, fig. 36) as
Bumastus orhicaudatus from the Prosser of Minnesota. The
posterior part of the cranidium is not preserved well enough to
determine whether or not a median pustule was present here
originally named in honor of Prof. A. D. Hole, of Earlham
College, Richmond, Indiana.

THE KIMMSWICK AND PLATTIN LIMESTONES

215

34. Bumastus rowleyi sp. nov.

Plate XXI, figs, 16 A, B; plate XXII, figs. 16 A, B

Cranidmm 19 mm. long, 21 mm. wide between the palpebral
lobes, and 22 mm. wide at the broadest part anterior to the
palpebral lobes. The general aspect of the cranidium resembles
that of Bumastus ambiguus Foerste from the Brassfield lime-
stone of Ohio and Indiana. The cast of the lower side of the
cranidium shows impressed lunettes along the dorsal groove.
These lunettes are separated by a distance of nearly 10 mm.
from each other. They are 3 mm. long and are 4 mm. distant
from the posterior margin of the cranidium. Both anterior and
posterior to the lunettes the dorsal grooves curve strongly out-
ward. Anterior to the lunettes the dorsal grooves are very
faint and terminate in distinct pits at points 15.5 mm. from each
other and 11 mm. from the posterior margin of the cranidium.
Each pit contains a small central granule. The cranidium is
moderately convex except toward the anterior margin where it
curves rather abruptly downward.

The associated pygidium is 22 mm. long, 27 mm. wide, and
has an anterior elevation of 7 mm. The cast of the lower sur-
face is moderately concave along the doublure, but the upper
surface appears to have been slightly convex from the more
convex middle parts of the pygidium as far as the posterior
margin.

Found at locality 3 in the Kimmswick limestone section along
Sanders branch in Balls County. Compared wiih. Bumastus inde-
terminatus Walcott, from the Leray-Black River of New York
(Bull. Mus. Comparative Zoology, 60, 1916, pi. 2), Bumastus
rowleyi has a longer, narrower cranidium with a different curva-
ture along the anterior part of the dorsal grooves on the cranid-
ium, and the general outline of the pygidium is more triangular,
especially posteriorly.

216

AUG. F. FOERSTE

35. Ceraurinus cf. trentonensis Barton

Glabella expanding anteriorly; in one cranidium 12 mm. long,
the width of the glabella increases from 8 to almost 10 mm.
from the rear toward the front. The general form of the glabella
is depressed convex, and is distinctly limited laterally by the
relatively shallow dorsal furrow. The first and second pairs of
glabellar furrows are distinctly curved ; from the dorsal furrow
they curve gently forward and then, for a longer distance, back-
ward, the inner ends terminating farther back than their outer
ends. The third or posterior pair of glabellar furrow^s is directed
diagonally backward, at an angle of about 55 degrees with the
median line of the glabella, joining the occipital furrow at points
only 2 mm. distant from each other. The posterior pair of
glabellar lobes is distinctly triangular. The first and second
pairs of glabellar furrows are narrow and sharply incised. The
surface of the glabella is almost smooth or minutely granulated.
On the fixed cheeks minute pits may be detected. In general
appearance, these cranidia resemble those of Cheirurus in which
the posterior pair of glabellar furrows is strongly defined as far
as its connection with the occipital furrow (Ohio Jour. Sci., 19,
1919, p. 396, pi. 19, fig. 7). .

Found at locality 4 on Sanders branch, in the Kimmswick
limestone.

In general aspect this species resembles Ceraurinus scofieldi
(Clarke) from the Platteville at Minneapolis, Minnesota (plate
XXII, fig. 19, of this bulletin), but the first and second pairs of
glabellar furrows in that species are less distinct and less curved.

36. Ceraurus cf. bispinosus Raymond and Barton
Plate XXI, figs. 18 A, B, C

The dorsal furrows limiting the sides of the glabella diverge at
angles between 22 and 27 degrees in different specimens. All
of the glabellar furrows are strongly indented. The eyes are
nearly opposite the second pair of glabellar furrows or slightly
farther forward. They are about equally distant from the

THE KIMMSWICK AND PLATTIN LIMESTONES

217

dorsal furrow and from the furrow following the posterior out-
line of the fixed cheeks. The ocular ridge is either faint or obso-
lete; when present, it starts off from the vicinity of the first
pair of glabellar furrows. The pustules tend to be more con-
spicuous anteriorly and also along two diverging lines which
extend from near the neck furrow forward toward the frontal
lobe in such a manner as to leave a median area in which the
pustules are less prominent. The pustules are less prominent
also between the two rows of more prominent pustules and the
lateral glabellar lobes. On the largest cranidium, 14 mm. long,
the most prominent pustules attain a height of 0.5 mm. None
are developed into spines. The fixed cheeks are indented with
pits, and between these there are a few granules of which several
tend to be prominent.

Found at locality 2 along Sanders branch, in the Kimmswick
limestone.

From typical Ceraurus hispinosus Raymond and Barton (plate
II, fig. 23 of this Bulletin), from the Black River formation of
the Ottawa area in Canada, the Ralls County specimens differ
chiefly in the absence of any pustules sufficiently strong to sug-
gest the presence of spines. From Ceraurus dentatus Raymond
and Barton, from the Trenton formation of Ontario and New
York, they differ in having more rotund glabellar lobes.

37. Ceraurus plattinensis sp. nov.

Plate XXI, figs, 18 A, B; plate XXIII, figs. 3 A, B

Cephalon relatively short. The continuation of the occipital
furrow along the posterior part of the fixed cheeks is nearly
straight as far as the genal angle ; in consequence the angle
between the posterior margin of the cephalon and the genal
spines appears more abrupt. In other respects the backward
curvature of the genal spines resembles that of Ceraurus den-
tatus, The lateral lobes of the glabella are small and rotund,
while those of Ceraurus dentatus are more nearly transversely
oblong. The eyes are set far back, almost opposite the second
pair of lateral lobes or slightly farther forward. A faint ocular

218

AUG. F. FOERSTE

ridge passes from the anterior pair of glabellar furrows obliquely
backward to the palpebral lobe, or may be entirely absent.
The axial lobe of the thorax is relatively broader and the free
terminations of the pleural segments spread out farther than in
Ceraurus dentatus. The strongly developed spines of the pygid-
ium not only curve strongly backward but are even slightly
convergent posteriorly. That part of the pygidium which is
included between these spines resembles the pygidium of Ceraurus
pleurexanthemus; no dentate margin is present as in Ceraurus
dentatus.

From the top of the Plattin limestone at the city quarry a
mile southeast of New London, along the lower part of Big
Creek, at the Buford Cave, and elsewhere in Ralls County.

38. Endymionia bellatula Savage

This species was described by Savage (Illinois Acad. Sci.,
1917, p. 273, pi. I, fig. 3) from the Thebes sandstone, near
Thebes, Illinois. It is cited by him also from Madison Creek, in
Calhoun County, Illinois, and from Dover church, in Pike
County, Missouri. Prof. R. R. Rowley discovered long ago a lo-
cality on the Goodman place, | mile west of Calumet post-
office, where this little trilobite occurs in great abundance about
3 or 4 feet above the base of the Buffalo shales.

39. Nileus sp.

Plate XXIII, fig. 4 A, B

Eyes very prominent, attaining an elevation of 2.5 mm. in
cranidia 15 mm. long, rising rather abruptly above the general
surface of the cephalon, and limited on the inner side by broad
though shallow depressions. In specimens whose palpebral
lobes are 10 mm. apart the shallow depressions along their
inner sides have their deepest parts about 6 mm. apart. The
median parts of the cranidia, between these shallow depressions,
may be regarded as the poorly defined glabella which broadens
anteriorly and merges into the general curvature of the cranidium.

THE KIMMSWICK AND PLATTIN LIMESTONES

219

Posteriorly a few specimens show traces of a prolongation of the
shallow depressions backward in the form of almost obsolete
dorsal furrows. The anterior part of the cranidium curves
downward without any indication of a marginal concave curva-
ture of the cephalon. Anteriorly the facial sutures meet at an
obtuse angle; nevertheless this angle is sufficient to indicate
that the facial sutures could not have been practically marginal.

Pygidium convex as far as the posterior margin. Axial lobe
almost or entirely obsolete. Antero-lateral margins curved
abruptly downward along a distinctly angular ridge. Between
this ridge and the antero-lateral angle, the slope is distinctly
concave. Posteriorly, the margin of the pygidium is slightly
angular rather than evetily convex.

From the limestone immediately beneath the Buffalo or
Maquoketa shales at the W. H. Benham locality, 3 miles south
of Frankford, in Pike County. This limestone rests on the top
of the typical Kimmswick, and is regarded as also of Mohawkian
age.

Compared with N ileus vigilans Meek and Worthen, from the
lower Maquoketa of the upper Mississippi valley, the Trenton
form here described, according to E. O. Ulrich (in a letter),
has much less prominent eyes, larger palpebral lobes; the eyes
situated farther from the anterior edge of the cephalon; the
anterior outline of the cephalon is more uniformly rounded;
the fixed cheeks are shorter; the front slope of the cranidium
is less sharply deflected; the anterodateral angles of the crani-
dium are less rounded; and the corresponding parts of the free
cheeks, where they bend around the front of the cranidium, are
narrower.

40. Proetus undulostriatus Hall.

A small cranidium, 3 mm. in length, was found at locality 2
along Sanders. Creek, in Ralls County. It differs from typical
Proetus undulostriatus from the Trenton (Snake Hill) of New
York, chiefly in the greater distance between the anterior mar-
gin of the glabella and the narrow anterior border of the cephalon.
Moreover, the intervening part is distinctly convex, and at the

220

AUG. F. FOERSTE

line of contact with the glabella it is distinctly indented. In
these particulars the Ralls County specimen agrees better with
the minute specimen of Proetus figured by Ruedemann (Bull.
New York St. Mus., No. 49, 1901, p. 62, pi. 4, figs. 5, 6, 7),
from the Trenton (Rysedorph) of New York.

41. Pterygometopus cf. lincolnensis Branson
Plate XXI, fig, 19

Pterygometopus lincolnensis Branson differs from Pterygometo-
pus eboraceus (plate II, fig. 20, of this Bulletin) , from the Trenton
of New York, in the absence of genal spines; the third pair of
lateral glabellar lobes is not confluent with the second; no tubercle
occurs on the occipital ring; the frontal lobe of the glabella is
shorter and broader; the eyes are larger; and the fixed cheeks
are smaller. At the top of the Plattin limestone, at the Buford
Cave, specimens resembling Pterygometopus lincolnensis occur,
but these have distinct genal spines. An examination of the
types of Branson^s species suggests that better preserved speci-
mens of the latter may also have genal spines.

x4nother form similar to Pterygometopus lincolnensis, found in
the Tyrone member of the Black River formation at High
Bridge, in central Kentucky, was described by me recently as
Pterygometopus confiuens Foerste (Ohio Jour. Sci., 19, 1919,
p. 396, pi. 19, fig. 19). It is refigured in this bulletin as figure
22 on plate II. It differs from the other known forms in the
flatness of the cranidium, including all of its lobes.

In Pterygometopus intermedius (Walcott), from the Black
River formation of the upper Mississippi Valley, all of the lat-
eral glabellar lobes are free (plate II, fig. 21 of this bulletin).

42. Remopleurides missouriensis sp. nov.

Plate XXI, fig. 17; plate XXII, figs. 17 A, B

In the best preserved cranidium, the width of the glabella, at
midlength of the palpebral lobes, is 7.2 mm., and each of the
palpebral lobes is slightly over 0.2 mm. in width. The length
of the glabella is 7 mm., and the neck segment adds 1 mm. in

THE KIMMSWICK AND PLATTIN LIMESTONES

221

estimating the length of the cranidium. The facial suture curves
abruptly downward, 5 mm. from the neck furrow, for a distance
of 1.2 mm., thus limiting the frontal lobe of the glabella laterally
with nearly parallel parts of the facial suture. Here the width
of the frontal lobe is slightly over 5 mm. Viewed from above,
the anterior outline of the frontal lobe, as far back as the ante-
rior margin of the palpebral lobes, appears rather evenly convex.
Viewed from in front, or from the side, the anterior part of the
cranidium rises abruptly for a height of 1 mm., then curves rap-
idly backward, attaining its maximum height of 2 mm. about
on line with the anterior pair of glabellar furrows. Except
along the frontal lobe, the glabella is only moderately convex,
especially posteriorly. The palpebral lobes are 4.5 mm. in
length, and extend as far back as the neck furrow. The poste-
rior margin of the glabella is distinctly defined by an abrupt
though very slight lowering of that part of the glabella forming
the neck segment. The median tubercle on the neck segment is
almost invisible.

There are three pairs of glabellar furrows. Of these the
middle pair is the longest. They are 2 mm. in length, and are
separated by a distance of 2 mm. Both furrows are slightly
curved, with their convex sides facing forward. Their outer
termination is slightly in advance of the inner one. The ante-
rior pair of glabellar furrows are about 1 mm. long, and are
separated by a distance of 2 mm. They also are slightly convex
toward the front. The posterior pair of glabellar furrows are
slightly over 1 mm. in length; they are separated by a distance
of almost 3 mm., and they are more convexly curved than either
of the other two pairs of furrows. All three pairs of furrows con-
sist of smooth lines, scarcely 0.1 mm. in wddth, in their present
condition appearing as slightly darker lines contrasted wfith the
whiter adjoining parts of the cranidium.

The surface of the cranidium is marked by minute granules
which become larger toward the margin of the cranidium.
Under a microscope the granules are seen to be elongated trans-
versely. Anteriorly, their upper surface slopes gradually down-
ward. Posteriorly, the slope is more or less abrupt, often being

222

AUG. F. FOERSTE

limited by a more or less lunate outline which becomes con-
spicuous on cross-illumination.

The hypostoma closely resembles that of Remopleurides striatu-
lus Walcott (Cincinnati Quarterly Journal of Science, II, 1875,
p. 347) in general form, and is 6 mm. in length.

From localities 2 and 4 in the Sanders Branch section, in the
Kimmswick limestone.

In Remopleurides striatulus Walcott (plate 41, figs. 18 A, B, C,
of this Bulletin), from the Trenton of New York, the smooth
lines indicating the glabellar furrows are indistinct, those corre-
sponding to the anterior and posterior pairs being extremely
obscure. The general curvature of the glabella is very moderate
except at its anterior margin, where the frontal lobe curves
more strongly downward.

Compared with Remopleurides striatulus^ the Ralls County
specimens have much more distinct indications of the glabellar
furrows; the frontal lobe curves downward more strongly and
for a greater distance; and the general aspect of the glabella is
somewhat narrower and less flattened.

In Remopleurides linguatus Ruedemann, from the basal Tren-
ton (Rysedorph) of New York, the anterior extension of the
frontal lobe is much narrower and more prolonged.

In Remopleurides tumidus Ruedemann, from the same horizon
and locality, the glabella is relatively broader, the anterior exten-
sion of the frontal lobe is shorter, and it is bounded laterally by
more converging facial sutures; moreover, the convexity of the
cranidium from front to rear is greater.

43. Bathyurus spiniger Hall

Plate XXII, fig. 20

Cranidium with posterior margin of neck ring dentate on
each side of the median spine. Those parts of the cranidium
which are immediately posterior to the palpebral lobes are
indistinctly preserved. From the top of the Plattin limestone,
in the city quarry, 1 mile southeast of New London, in Ralls
county.

THE KIMMSWICK AND PLATTIN LIMESTONES

223

appendix: SILURIAN SPECIES
44. Platymerella manniensis Foerste
Plate XXIII, figs, 5 A-H

Platymerella manniensis Foerste, originally described from the
Brassfield of western Tennessee, and later found by Savage in
the basal part of the Sexton Creek equivalent of the Brassfield in
northeastern Missouri and adjacent Illinois, and also in the
northeastern corner of Illinois, has been found recently in
the basal layers of the Brassfield at Lawshe, in Adams County,
Ohio. The Lawshe specimens are of special interest on account
of exposing the interior of the valves. Viewed from the exterior,
the dissociated valves are so closely similar that it is difficult to
distinguish the pedicel valves from the brachial ones. When
attached to each other, the umbo of the pedicel valve rises farther
above the hinge-line, so that the beak is more curved.

Pedicel valve (figs. 5 A, B, C, D) with an oval or rhomboid
spondylium, about 5 mm. long, strongly divergent from the
surface of the interior of the valve, and supported by a thin,
tall median septum which disappears within 5 mm. from the
anterior margin of the spondylium. Pitted ovarian markings
are present on the posterior part of the interior.

Brachial valve (figs. 5 E, F, G) with two short crural plates,
about 3 or 4 mm. in length, converging along the median line
and forming a cruralium resting directly upon the bottom of
the interior of the valve. The crural prolongations of the an-
terior margin of the crural plates rarely are preserved. Along
the median line of the shell the anterior part of the cruralium
is prolonged into a low and narrow septal line. In one speci-
men (fig. 5 H) the crural plates rest directly upon the bottom
of the interior of the valve, and are prolonged anteriorly into
two sharp parallel ridges, about a millimeter in height, 3 or 4
mm. long, and slightly over 2 mm. apart.

The genus Platymerella is characterized by its flattened,
elongate form; the absence of a cardinal area; the delthyrium
is concealed entirely by the contact of the beaks of the two

224

AUG. F. FOERSTE

valves with each other; both the spondylia and cruralia are
short, the former being supported on a high median septum
and the latter being sessile along the median line on bottom of
the interior of the valve. The exterior of the pedicel valve
shows no tendency toward a median depression or groove. The
genus is regarded as related most nearly to Pentamerella, a Devonian
genus. In Pentamerella the shell is short, deep, and galeatiform,
the spondylium is not supported by a long septum, there is a
tendency toward a narrow sinus on the exterior of the pedicel
valve, the delthyrium is exposed, there is a pseudo-cardinal
area, and the anterior septal extensions of the crural plates
unite at the base so as to form a cruralium resting on the inner
surface of the brachial valve.

PLATE XXI

Fig. 1. Strophomena cf. incurvata. Pedicel valve. Locality 3 on Sanders
branch, in Kimmswick limestone.

Figs. 2, 3. Rafinesquina deltoidea. Pedicel valves. Locality 4 on Sanders
branch, in Kimmswick limestone.

Fig. 4. Parastrophia hemiplicata var. Pedicel valve. Locality 4 on Sanders
branch, in Kimmswick limestone.

Fig. 5. Platystrophia shepardi. Brachial valve. Locality 3 on Sanders
branch, in Kimmswick limestone.

Fig. 6. Holopea cf. parvula. From Conn’s Ford, at top of Plattin limestone.

Fig. 7. Holopea concinnula. From Conn’s Ford, at top of Plattin limestone.

Fig. 8. Hormotoma gracilis angustata. From Conn’s Ford, at top of Plattin
limestone.

Fig. 9. Conularia sp. Enrolled fragments. From city quarry, 1 mile south-
east of New London, near top of Plattin limestone.

Fig. 10. Hyolithes baconi. A, convex side of fragment, with lower end
restored; from Buford cave. B, flattened side of second specimen, from J. H.
Smith farm. Both from top of Plattin limestone.

Fig. 11. Hyolithes baconi. Convex side. From Buford Cave, at top of
Plattin limestone.

Fig. 12. Conularia plattinensis. Fragment apparently exposing almost all of
one face. From Conn’s Ford, at top of Plattin limestone.

Fig. 13. Ctenodonta sp. (gibberula group). Left valve. From 1 mile north-
west of Spalding Springs, near home of H. W. Ogle, at top of Plattin limestone.

Fig. 14. Parallelodus obliquus. Right valve. From Conn’s Ford, at top of
Plattin limestone.

Fig. 15. Bumastus holei. A, cranidium; B, pygidium. From locality 3 on
Sanders branch, in Kimmswick limestone.

PLATE XXI

BULLETIN Scientific Laboratories Denison University Vol. XIX

FOERSTE: KIMMSWICK AND PLATTIN FOSSILS

Fig. 16. Bumastus rowleyi. A, cranidium; left side restored; B, pygidium.
Locality 3 on Sanders branch, in Kimmswick limestone.

Fig. 17. Remopleurides missouriensis. Cranidium, with the smooth lines
representing the glabellar furrows darkened. Locality 2 on Sanders branch, in
Kimmswick limestone.

Fig. 18. Ceraurus cf. bispinosus. A, B, fragments of cranidia with traces of
ocular ridge on right side. C, cephalon lacking the free cheeks, genal spine on
right side restored. Locality 2 on Sanders branch, in Kimmswick limestone.

Fig. 19. Pterygometopus cf. lincolnensis. Cephalon, left side and part of
margin restored. From Buford Cave, at top of Plattin limestone.

Fig. 20. Ceraurus plattinensis. A, an almost entire individual, proximal
parts of genal spines widened by crushing; from city quarry, one mile southeast
■of New London. B, Cephalon, from Harvey farm on lower Big Creek, at top of
Plattin limestone.

Additional figures of some of the specimens illustrated on this plate appear on
the following plate.

PLATE XXII

Fig. 1. Strophomena incurvata. Curvature of median line of valves of
specimen figured on preceding plate; with pedicel valve on right.

Figs. 2, 3. Rafinesquina deltoidea. Outlines of specimens figured on preced-
ing plate, viewed from the side.

Fig. 4. Parastrophia hemiplicata var. A, second specimen, from same
locality as that figured on preceding plate, weathered so as to show spondylium
formed by dental lamellae, supported by median septum anteriorly.

Fig. 5. Zygospira deflecta. A, pedicel valve; B, anterior view; from the
Trenton of Lewis County, New York. Copied from figures 4 a, b, on plate 33, of
Pal. New York, 1, 1847.

Fig. 6. Holopea parvula. From Flanagan member, near top of Trenton,
near Burgin, in central Kentucky. Copied from figure 19, on plate 79, of Pal.
Minnesota, III, pt. 2, 1897.

Fig. 7. Holopea concinnula. From the Platteville near Beloit, Wisconsin.
Copied from figure 6 on plate 79 of Pal. Minnesota, III, pt. 2, 1897.

Fig. 8. Hormotoma gracilis angustata. From top of Decorah formation at
Cannon Falls, Minnesota. Copied from figure 32 on plate 70 of Pal. Minnesota
III, pt. 2, 1897.

Fig. 9. Conularia sp. A, granular surface, magnified 12 diameters, to show
arrangement of granules in transverse and in longitudinal rows. B, several
cross-sections of the enrolled fragments. From same series as the specimen
represented by figure 9 on the preceding plate.

Fig. 10. Hyolithes baconi. Cross-section of specimen used for figure 10 B,
on preceding plate.

Fig. 11. Hyolithes baconi. Cross-section of specimen used for figure 11 on
preceding plate.

Fig. 12. Conularia plattinensis. Imaginary cross-section of specimen simi-
lar to that used for figure 12 on preceding plate, indicating position of the pair
of vertical ridges along the median part of the faces, supported interiorly by
short septal striations.

Fig. 13. Ctenodonta gibberula. Mould of interior of left valve, from the
Platteville at Minneapolis, Minnesota. Copied from figure 37 on plate 42 of
Pal. of Minnesota, III, pt. 2, 1897.

Fig. 14. Modiolopsis consimilis. Right valve, from the Stones river group
at Murfreesboro, Tennessee. Copied from figure 17 on plate 42 of Pal. Minne-
sota, III, pt. 2, 1897.

Ife

FOERSTE: KIMMSWICK AND PLATTIN FOSSILS

Fig. 15. Bumastus cf. billingsi. A, B, outlines of cranidium and pygidium
figured on preceding plate, viewed from the side. C, specimen figured by Clarke
as Bumastus orhicaudatus ; copied from figure 36 on page 722, of Pal. Minnesota,
III, pt. 2, 1897.

Fig. 16. Bumastus rowleyi. A, B, outlines of cranidium and pygidium fig-
ured on preceding plate, viewed from the side.

Fig. 17. Remopleurides missouriensis. A, outline of specimen figured on
preceding plate, viewed from the side; B, viewed from the front, showing the
frontal lobe.

Fig. 18. Remopleurides striatulus. A, specimen from type locality, in U. S. .
Nat. Mus., viewed from above; B, lateral view of same; C, short nodose stria-
tions, magnified 80 diameters. From Trenton limestone at Trenton Falls, New
York.

Fig. 19. Ceraurinus scofieldi. Cranidium, from Platteville limestone at
Minneapolis, Minnesota. Copied from figure 55 on page 735 of Pal. Minnesota,
III, pt. 2, 1897.

Fig. 20. Bathyurus spiniger. A cranidium, with fixed cheeks posterior to
palpebral lobes indistinctly defined. From city quarry, 1 mile southeast of
New London, near top of Plattin limestone.

Fig. 21. Pterygometopus intermedins. Cephalic view of enrolled specimen;
species occurs both in Platteville and Decorah of Minnesota. Copied from
figure 45 on page 728 of Pal. Minnesota, III, pt. 2, 1897.

Fig. 22. Pterygometopus confluens. Cranidium from Tyrone member of
strata exposed at High Bridge, Kentucky. Showing confluence of outer parts
of first and second pairs of glabellar lobes, as in Pterygometopus eboraceus and
Pt. lincolnensis.

Fig. 13. Ceraurus bispinosus. Fragment of cranidium, from Black River
h’mestcne at Tetreauville, province of Quebec. Copied from figure 4 on plate I
of Bulletin of Museum of Comparative Zoology, 54, no. 20, 1913.

Fig. 24. Comarocystites shumardi. A, fragment of theca adjoining anal
aperture, viewed from interior. B, a single thecal plate viewed from interior.
From top of quarry in Kimmswick limestone, | mile northwest of West Kimms-
wick, Missouri.

PLATE XXIII

Fig. 1. Mcewanella raymondi. Brachial valve. From Mincke, St. Louis
County, Missouri; in Kimmswick limestone.

Fig. 2. Rhynchotrema rowleyi. A, B, pedicel valves, exteriors. C, pedicel
valve, interior. D, brachial valve, interior. From small knob, 3 miles east of
Frankford, on road to Louisiana; in Buffalo or Maquoketa shales.

Fig. 3. Ceraurus plattinensis. A, pygidium. B, hypostoma. From Buford
Cave, 2 miles west of New London; at top of Plattin limestone.

Fig. 4. Nileus sp. A, cranidium. B, pygidium. From a coarse lime-
stone layer immediately beneath the Buffalo or Maquoketa shales, east of the
home of W. H. Benham, 3 miles south of Frankford, on a branch of Peno creek.

Fig. 5. Platymerella manniensis. A-D, pedicel valves, interiors. E-H,
brachial valves. From Lawshe, Adams County, Ohio. In basal part of Brass-
field formation.

Fig. 6. Clitambonites cf. diversus. Pedicel valve, lateral view. From
Mincke, in St. Louis County, Missouri; in Kimmswick limestone.

Fig. 7. Beatricea gracilis Ulrich. Lateral view of fragment of a much longer
stem. From quarry east of pike, a short distance north of Auburn, Missouri;
in Auburn limestone.

Fig. 8. Zygospira nicolleti. A, brachial valve. B, pedicel valve. From
Buford Cave, 2 miles west of New Icndon, at top of Plattin limestone.

BULLETIN Scientific Laboratories Denison University

PLATE XXIII

FOERSTE: BRASSFIELD, MAQUOKETA, KIMMSWICK AND PLATTIN FOSSILS

VOLUME X

NO.

SEPTEMBER, 1921

DENISON UNIVERSITY

BULLETIN

II

Journal

^ A'*

OF THE

Scientific Laboratories

Volume XIX

Articles 13-16

Pages 225 to 329

13. Education for Scholarship. By William E. Castle 225

14. The Cytology of the Sea-side Earwig, Anisolabis maritima Bon.

Part 1. By Sidney I. Kornhauser 234

15. Notes on Arctic Ordovician and Silurian Cephalopods. By

Aug. F. Foerste 247

16. Revolution vs. Evolution: The Paleontologist Renders His Verdict.

By Kirtley F. Mather 307

Subject and Author Index 325

GRANVILLE, OHIO

The University Bulletin is issued bi-monthly and is entered at the
Post Ofhce in Granville, Ohio, as mail matter of the Second Class

JOURNAL

OF THE

SCIENTIFIC LABORATORIES

OF

DENISON UNIVERSITY

Edited by

KIRTLEY F. MATHER

Permanent Secretary, Denison Scientific Association,
Granville, Ohio

The entire file of volumes 1 to 13 was destroyed by fire; no publications issued prior to
1907 are now available. Volumes 14 to date may be obtained from the. editor at $2.00 per
volume, with the exception of volume 15, the price of which is $1.00. Separate parts, as listed
below, may be purchased at the prices indicated.

VOLUME 14

ArticleB 1-5, pp. 1-60; Nov., 1908 $0.60

Pre-WiscoiiBin drift in the Finger Lake Region of New York; F. Carney. 16 pp., 4 figs, ,

An esker group south of Dayton, Ohio; Earl R. Scheffel. 15 pp., 6 figs.

Wave-cut terraces in Keuka Valley, older than the recession stage of Wisconsin ice; F. Carney. 12 pp., 3 figs.

A form of outwash drift; F. Carney. 8 pp., 1 fig.

State geological surveys and practical geography; F. Carney. 6 pp.

Articles 6-10, pp. 61-188; April, 1909.. $1.00

Fossils from the Silurian formations of Tennessee, Indiana, and Kentucky; Aug. F. Foerste. 56 pp., 4 plates.
Studies on Babbit and other alloys; 10 pp. J. A. Baker.

A statigraphical study of Mary Ann Township, Licking County, O. 28 pp., 15 figs. F. Carney.

Significance of drainage changes near Granville, Ohio; Earl R. Scheffel. 17 pp., 2 figs.

Age of the Licking Narrows; K. F. Mather. 13 pp., 6 figs.

Articles 11-16, pp. 189-287; June, 1909 $0.76

A spectrometer for electromagnetic radiation; A. D. Cole. 10 pp., 6 figs.

The development of the idea of glacial erosion in America; F. Carney. 10 pp.

Preliminary notes on Cincinnatian fossils; Aug. F. Foerste. 20 pp., 1 plate.

Notes on Spondylomorum Quaternariuni Ehrenb; M. E. Stickney. 5 pp., 1 plate.

The reaction to tactile stimuli and the development of the swimming movement in embryos of Diemyctylus torsus,

Eschscholtz; G. E. Coghill. 21 pp., 6 figs.

The raised beaches of the Berea, Cleveland, and Euclid sheets, Ohio. F. Carney. 25 pp., 5 figs.

Articles 17-18, pp. 289-442; November, 1909 $1.00

Preliminary notes on Cincinnatian and Lexington, fossils; Aug. F. Foerste. 45 pp., 6 plates.

The Pleistocene geology of the Moravia Quadrangle, New York; Frank Carney. 105 pp., 27 figs.

VOLUME 15

Article 1, pp. 1-100; March, 1910. $1.00

Bulletin in commemoration of Clarence Luther Herrick.

EDUCATION FOR SCHOLARSHIP^

WILLIAM E. CASTLE

James Bryce, that observing and benevolent and wise English-
man, who spent so many years among us as his country’s repre-
sentative at Washington, and who knows us Americans better
than we know ourselves, — Bryce has said that the finest thing in
American life is our universities. Here our youth turn aside
from the work-a-day world in which they grow up, and to which
they will presently return, and for a few years while the mind
is vigorous and keen come in daily contact with the best products
of man’s thinking in all the ages that have gone before. If with
such contacts our young men and young women do not themselves
learn to think correctly and act wisely, it will not be for lack of
opportunity to learn but rather because of failure to appreciate
properly and to seize effectively the opportunities offered. That
our young people do, with few exceptions, value the opportuni-
ties of college life highly is shown by the practical unanimity
with which in later life they send their own children to college,
and when the college needs money to carry on and enlarge its
work, they give money freely in its support, more freely than
for any other object you can mention.

Why is it, do you suppose, that we value so highly our college
days and wish our children to enjoy college days too? I can
mention one reason; it is because in college days, we have oppor-
tunity to think about and to discuss general questions, aside
from their immediate application to our own personal interest.
This makes for clear thinking and sound judgment. We do
not allow a judge to sit on a case in which he is personally inter-
ested. We think it is difficult for him to judge impartially under
such circumstances. Similarly we want our young people to be

1 An address delivered at the Ninetieth Annual Commencement Exercises of
Denison University, June 15, 1921.

225

226

WILLIAM E. CASTLE

free from bias when they are weighing general questions and are
adopting general principles which are to serve as constitutions
of personal conduct for their daily lives. This is the essence of
that academic atmosphere’^ which surrounds a university, and
which means freedom from bias, and which is sometimes con-
demned by men who call themselves ^ ^ practical, ” just because it
does mean freedom from bias and does not permit of the decision
of large questions on the basis of small, local and selfish interests.

The academic atmosphere is friendly to thought, to inquiry,
to- the extension of every field of knowledge, without pausing to
inquire whether it is immediately useful.

Benjamin Franklin, a self-educated man of genius, founded the
oldest of the learned societies of America, whose official title
is The American Philosophical Society held at Philadelphia for
the Promotion of Useful Knowledge. Franklin, apparently,
thought to rule out all knowledge that was not useful, as those
do today who would admit to educational programs only voca-
tional studies. But if Franklin or his successors ever seriously
attempted to exclude from consideration in his Society any
branch of knowledge on the ground that it was not useful, they
long ago abandoned the attempt. The two-day program of the
Annual Meeting of the Society which I sat through two years
ago in the Society’s little old building on historic Independence
Square, with Ben. Franklin’s crude apparatus in glass cases
round the wall and outside the noise of a great commercial
city roaring by,- — that program coVered every subject under the
sun, from the folk lore of primitive savage tribes and the philoso-
phy of primitive Christianity, to the best methods of preventing
erosion on sea-beaches, and the ultimate constitution of atoms.

No man, however wise, can tell us what knowledge is useful
and what knowledge is not or is not likely to be useful. Great
industrial establishments are coming to appreciate this fact.
They recognize the potential value of fundamental truth, however
abstruse. For example the General Electric Company employs
eminent physicists drawn away by high salaries from the labora-
tories of our universities, for what purpose? To plan electrical
machines or to devise new uses for electricity? No, to study the

EDUCATION FOR SCHOLARSHIP

227

composition of the atoms of which all material objects are
composed; hypothetical structures, infinitely small, which no
man has ever seen. Why is the General Electric Co. interested
in the pursuit of an investigation so abstruse as this? Because
the man who can tell us what holds the atoms , together, will
place at our disposal unlimited power. If we ever learn how to
utilize atomic energy, we can discontinue the mining of coal and
the pumping of oil. The General Electric Co. is willing to risk
a little of its surplus in the venture of trying to hasten that day.

Since it is impossible to say what knowledge is useful, the
university properly takes all knowledge as its field, and seeks
to increase and to diffuse that knowledge. It seeks to place on
its faculty men or women who have contributed in some way
to the increase of knowledge, believing that such meu and women
are calculated to inspire in their pupils a zeal for knowledge and
a desire to increase knowledge, or else the university chooses for
its faculty those who have shown an unusual aptitude for impart-
ing knowledge, because the ability to acquire and to impart
knowledge are not always found in the same individual, indeed
such a happy combination is rather unusual. For this reason
university faculties should include both types of men, teachers
and investigators, but the fundamental or introductory courses
should always be in charge of those ^^apt to teach, filled with
enthusiasm for knowledge and bursting with a desire to impart
it. Such only are born teachers. Unless the student, early in
his course, acquires a taste for learning and desires to go on
learning the rest of his life, he will never make a scholar, which
means that he will not get the most out of college life. For
after all, the serious business of college life is scholarship. You
would never know this from reading the newspapers. You would
suppose that a university was great in proportion to the strength
of its athletic teams, but that is not so. The effectiveness of
gun fire is measured not by the amount of noise made but by the
proportion of hits. Scholarly achievements in university life
are hits, athletics mostly noise.

Scholarship does not consist in the mere accumulation of facts,
but in the ability to take a body of facts and draw sound conclu-

228

WILLIAM E. CASTLE

sions from them. Edison reports that the college men did not
stand particularly high in the examinations which he set to test
possession of a mass of miscellaneous information. By implica-
tion the colleges are to blame. But the colleges are not concerned
with imparting miscellaneous information to their students.
If that is what is wanted, the student would do well to stay
at home and study the World Almanac. The colleges are
concerned primarily in teaching young people how to think.
Some one has said that it makes no difference what subject you
study provided you study it in the right way, so as to master
it, so as to make it your own, so that if all the books on a subject
were destroyed, all the facts and statistics about it were for-
gotten, you could sit down and block out the principles on which
the subject could be built anew. That is scholarship.

While it is true, I believe, that all branches of knowledge have
educational value, it is not true that all have equal educational
value, or are equally serviceable in developing all types of minds.
Some studies are more useful as instruments of education at one
stage of mental development or to one type of mind than to
another. Experience shows that language study is one of the
earliest available and most generally useful instruments of educa-
tion. Students of mankind tell us that in the development of the
race growth in thought and in its vehicle, language, went hand
in hand, each process stimulating the other, thought being incapa-
ble of expression or even of formulation except as suitable lan-
guage was found for it. What was true of the race is true in the
development of the individual. Language is indispensable to
thought but the amount of language study which can profitably
be undertaken in individual cases varies greatly. Some find the
mother tongue all they are able to master, and it is indeed ade-
quate, if the other mental powers are well developed, to place
at one’s disposal in translation or otherwise the wisdom of all
the ages. A boy who is dull at language, should not be kept at
language study all his school days, until his interest is killed in
studies of every sort, but should be allowed to go on in other
fields, as he shows capacity to do so.

EDUCATION FOR SCHOLARSHIP

229

I speak of language study, by way of illustration merely. The
principle stated will apply equally well to any other subject. All
minds are not alike and so we should not have one stereotyped
course of study for all. We might apply to education what
Bacon said concerning food, ^^Now good digestion waits on appe-
tite and health on both. The educational food must be appetiz-
ing if the student is to digest it and grow mentally by reason
of it. While the tastes and aptitudes of the student should be
influential in determining the choice of his studies, they should
not be the exclusive consideration, any more than we should f eed
our children exclusively on candy just because they like it. We
feed them what we think is good for them and try to present it
to them in an appetizing form. That seems to be the essence of
rational child feeding.

Pope’s dictum that ^^The proper study of mankind is man”
is often quoted by those who favor the humanities in educational
programs: language, literature, history, philosophy, and the
like; and it must be admitted that such studies have the widest
appeal, since they embody an epitome of all that man has thought,
said or done since he emerged from savagery, and thus involve
the rudiments of civilization.

But the story of man before the beginning of the historical
period is a much longer one than that which deals with the com-
paratively brief and modern civilized period. Yet it is a harder
task to decipher that story. It has to be done in the light of
archeology and anthropology, which in turn lean strongly on
zoology and botany, and they on geology, chemistry, physics,
and astronomy, and all of them on mathematics. So there is
no subject which is not important to a proper understanding
of man and his place in nature. The task is too great for any one
mind to undertake to master them all and so scholars have to
divide the field among them and each one work in his own corner.
Only when the mind is young and fresh and receptive is it given
to anyone to make a general survey of the whole field of knowl-
edge, and select the small portion which with proper industry
he may hope to make his own. These are the glorious days of
youth, college days, when under the guidance of inspiring teach-

230

WILLIAM E. CASTLE

ers, we are permitted to go up into a high mountain and look
over into the promised land of knowledge spread out before us
like a map. For some of us that vision ends with college days,
but the memory of it remains and makes us wish that our chil-
dren may have it too, and that is why we send our sons and
daughters to college.

When I was a student in college two rival theories concerning
the origin and nature of man were placed before us. Part of
the faculty favored one theory, part the other, so we students
had to do some thinking of our own if we reached any conclusions,
and to think for himself is not a bad training for the student.

According to one theory, man was not of the earth though he
was on the earth. Heaven was his home, here he was a stranger,
a sojourner, a wayfarer, defiled by contact with things earthly,
trying to divest himself as rapidly as possible of the polluting
medium in order that he might again reach a pure state. He had
nothing to hope for in life except to make a safe escape from it.

According to the other theory man was a product of the earth
itself, the highest stage at present in a process of orderly develop-
ment. Indications of what some of the earlier stages were,
through which he had passed, were seen in the lower forms of life,
animal or plant, or even in the rocks, which as they decay form
soil in which plants grow, on which in turn animals feed. On
this theory, man was no stranger here on earth but a part of a
creative process still in progress.

Some of us students adopted one theory, some the other, and
I suppose today we hold much the same views that we adopted
then. People do their best thinking, as a rule, when they are
young, make up their minds then on fundamental questions and
rarely change them afterward. But fortunately these same
fundamental questions come up for study anew in every genera-
tion and are never settled. Every student for himself can apply
to them the try-square of truth.

My own interest in this- question of the nature and origin of
man led me into the study of biology and ultimately into that of
heredity, at a time when great discoveries were being made in
this field. It is safe to say that since 1900 more has been

EDUCATION FOR SCHOLARSHIP

231

learned about heredity than had been discovered in all the
preceding centuries. This subject has been studied chiefly in
the case of plants and the lower animals, and iriuch of practical
value has been learned concerning it. We are now able, through
a knowledge of some of the laws of heredity, to breed animals
and plants better adapted to agricultural needs than any which
existed before. We know how to produce any desired combina-
tion of characters in our animals and plants, provided we can
first discover the characters which it is desired to combine.
We know, too, that these same laws which govern heredity in
plants and animals govern heredity also in man. Whatever
theory we hold about the past of man, about his origin, we cannot
fail to see that this knowledge of heredity places in the hands
of the human race the possibility of controlling in a measure its
own future. So far as the laws of heredity are concerned the
human race could be moulded to an improved type as easily as
our cultivated plants and domestic animals can be. Our knowl-
edge of human heredity is yet too incomplete to warrant the sug-
gestion of specific measures, except in a very tentative way, but
it is time that we began thinking about the subject, and placing
it before the minds of our students as a subject for investigation.

Common observation tells us that some races of mankind are
better endowed physically, mentally or morally, than others.
The same is true of families in a community. We have in
America about every racial stock in existence poured into the
melting pot, and we have a good opportunity to compare them
and estimate their racial values. Shall we let them all come with-
out restraint or shall we make a selection of the ingredients? A
student of heredity who desired to improve the human stock on this
continent would have no hesitation in favoring selective restric-
tion. Even within our own borders, there occur human strains
of low mentality, or loose morals, usually both, that the commu-
nity would be better off without. The animal husbandman sees
to it that inferior strains do not increase. Can human society
do the same?

Then there are good human strains, no less than bad ones,
families which generation after generation produce men of good

232

WILLIAM E. CASTLE

physique and sound minds or skilled hands. In their produc-
tion the elements of environment, education and family tradi-
tion must not be disregarded, but after all due allowance is made
for these factors, it is still true that heredity is an important
element in producing good family strains no less than bad ones.

Can a way be found, without undue interference with personal
liberty, to increase the good human strains and to decrease the
poor ones?

Finally there is another problem which the human race must
face in the light of biology as well as of history, that of popula-
tion. There is a limit to the number of people who can live
comfortably on a limited amount of land. It is true that the
world supports much larger populations now than it did a few
centuries ago and supports them in much greater comfort, due
chiefly to advances in applied science, but still many countries
are overcrowded. Overcrowding leads in time to poverty,
famine, and war. Would not an intelligent control of the increase
of population act as a deterrent to war and its attendant miser-
ies? Our college graduates will not solve the problem by limiting
the size of their own families. They have gone too far already
in that direction and are not now replacing themselves in the
population. Roolsevelt pointed out very clearly the consequences
of this policy, which he denounced as ^Tace suicide.’’ He did
not wish to see our children cheated of their birthright, and this
■fair land won from the wilderness by the daring and toil and
endurance of our fathers, abandoned by us to the swarming hordes
of Europe, Asia and Africa.

At the same time it is not wise for us to adopt a policy of non-
intercourse with the rest of the world. The part is not greater
than the whole. Our civilization is European civilization, the
world civilization of today. When that falls, ours falls. What
we need is intelligent study of the whole question of population,
the factors that enter into its increase, its stabilization, and its
ultimate control. The question should be approached in the
academic spirit, without bias, without hysteria, without fanati-
cism, in a spirit of fairness to all races and conditions of men.

EDUCATION FOR SCHOLARSHIP

233

The teachings of biology agree with the teachings of religion
as regards the whole duty of^ man. They show that everywhere
and always the interests of the race are superior to the interests
of the individual. They exalt altruism and condemn selfishness.
Some of us thought, when we adopted different theories about
man’s origin, that we had come to the parting of the ways, and
that thenceforth pur paths would diverge, but we have been
surprised again and again to find each other working shoulder
to shoulder in the same great tasks of humanity and fighting
as comrades for the right and against the wrong.

We have about concluded that our differences were over
definitions merely, not realities.

‘‘In the beginning God created the heavens and the earth,”
are the simple, grand words of the first chapter of Genesis.
These are the words of a modern poet,^ who has spent his life
in the academic atmosphere of an American college:

A fire-mist and a planet,

A crystal and a cell,

A jelly-fish and a saurian.

And caves where the cave-men dwell;

Then a sense of law and beauty
And a face turned from the clod.

Some call it Evolution,

And others call it God.

A picket frozen on duty,

A mother starved for her brood,

Socrates drinking the hemlock,

And Jesus on the rood;

And millions who, humble and nameless,

The straight, hard pathway plod.

Some call it Consecration,

And others call it God.

2 W. H. Carruth, Each in his own tongue. G. P. Putnam’s Sons, N. Y. 1908.

THE CYTOLOGY OF THE SEA-SIDE EARWIG,
ANISOLABIS MARITIMA BON.

Part I

SIDNEY I. KORNHAUSER

^From the Zoological Laboratory of Denison University, and the Biological Labo-
ratory of the Brooklyn Institute of Arts and Sciences at Cold Spring
Harbor, Long Island

WITH THREE PLATES

CONTENTS

1. Introduction 234

2. Historical Review 235

3. Methods 236

4. The Gonads 237

5. The Diploid Chromosomes 238

6. The Spermatocyte Chromosomes 240

7. Discussion 244

8. Summary 245

9. Bibliography 246

10. Explanation of Plates 246

1. INTRODUCTION

The forficulid, Anisolabis maritima Bon., which is found under
the stones and riff-raff at the high-tide mark, is especially beauti-
ful material for cytological study. The chromosomes are clear
and distinct; the cytoplasmic structure, nicely demonstrable;
and good preservation is not difficult. The differentiation of the
oocyte and nurse cell and their subsequent growth present many
interesting problems which will be taken up in another paper.
The origin and distribution of mitochondria in both the sex
and the embryonic cells may also be studied profitably in this
species. For the present, the author has confined himself chiefly
to the chromosome number, and the origin and fate of the sex-
chromosomes in the male. The work was begun in the summer

234

CYTOLOGY OF ANISOLABIS MARITIMA BON.

235

of 1915, suffered many delays due to the World War, but was
taken up again in the spring of 1920.

I wish to express my thanks to the American Association for
the Advancement of Science, which, through its Committee on
Grants for Research, has enabled me to purchase microscopical
lenses suitable for cytological study. These lenses have aided
greatly in the completion of the paper.

2. HISTORICAL REVIEW

Two of the Forficulidae have been previously worked upon
from a cytological standpoint, Forficula auricularia and the pres-
ent species, Anisolabis maritima; the bulk of the work having
been done upon the former species. The accounts claim a great
variability in the diploid and haploid number of chromosomes,
and several combinations of sex-chromosomes have ’ been
described.

The most recent and detailed contribution to the cytology
of the forficulids is that of Payne (T4) on the variability of the
chromosomes of Forficula. Payne states that the spermato-
gonial metaphases show from 24 to 27 chromosomes, twenty-
four being the most usual number. The spermatocytes were
found to have from 11 to 14 chromatic elements present. Zwei-
ger (’06) states that the spermatogonial count was 24 or 26,
the latter number being the more prevalent. He states that
either 12 or 13 chromosomes may appear in the primary spermato-
cytes, and 12 to 14 in the secondary spermatocyte metaphase
plates.

Stevens (TO) considered 24 the correct spermatogonial number
and 12 the haploid number, one of the twelve seen in the primary
spermatocytes being an unequal hetero chromosome group, which
separated reductionally in the first maturation division.

Pantel (T2), whose work deals mainly with the degeneration
of cells due to the presence of protozoan or insect parasites,
described a variable number of chromosomes in Forficula. Sper-
matogonia have either 25 or 26 chromosomes; and spermato-
cytes, 11 to 13 chromosomes. He does not insist, however, that

236

SIDNEY I. KORNHAUSER

this variation, which had already occupied the attention of such
pioneers as Carnoy, La Valette, St. George and Sinety, should
be produced by parasitism.

Brauns (G2), in his study of the oogenesis of Forficula auric-
ularia, believes that the haploid number in the female is 13.
He quotes Professor Ludwig Will of Rostock as saying that the
male diploid number of Forficula is 25, and the female diploid
number 26; but that some males show 24 chromosomes in their
spermatogonia. If is a striking coincidence that my counts on
Anisolabis are in very close agreement with the results of Pro-
fessor Will.

Randolph (^08) worked on Anisolabis and described 24 chromo-
somes as the diploid number in both sexes. In the primary
spermatocytes she pictures a pair of almost equal hetero chromo-
somes which lag in the anaphase of the first maturation mitosis,
but her results are not at all in accord with those described in
the present paper.

3. METHODS

The material studied consisted of gonads and embryos.
Nymphs were found best for the study of the germ cells. The
animals were all collected at or near Cold Spring Harbor, Long
Island, during June, July and August of several summers since
1915.

The best fixatives were Flemming’s fluid (strong), Bouin’s
fluid and Benda’s modification of Flemming’s fluid. Various
stains were employed. The Flemming material was stained in
Heidenhain’s haematoxylin, counterstained with Orange G or
with safranin and lichtgrlin. The Benda material was stained
either with alizarin and crystal viplet, or with methyl green and
acid fuchsin of Bensley. These last two were especially valuable
in the study of the xxy-complex.

Smears of testes were made in a moist chamber, immediately
exposed to osmic fumes for a few seconds, and then immersed
in a fixing fluid; care being taken to avoid drying. Such
smears were then treated and stained like sections.

CYTOLOGY OF ANISOLABIS MARITIMA BON.

237

Embryos were removed from their chorionic coverings before
fixation in Flemming^ s fluid.

The abundance of material, the large number of preparations
made, and the variety of methods employed lead the author to
believe that his results are fairly accurate.

All drawings were made with the aid of a camera lucida, using
a 1.5 mm. Zeiss apochromatic objective and a 20 X compen-
sating ocular. This gave an initial magnification of 3300
diameters. The drawings were reduced in the reproductions,
plate XXIV about one-third and plates XXV and XXVI about
two-fifths.

4. THE GONADS

Each testis consists of two long narrow tubules surrounded
by a fat sheath. The length and narrowness of the tubules
gives a good seriation of stages from the blind tip to the bottom
where the sperm pass into the vas efferens. Near the blind or
cephalic end of the tubule is a large apical cell, surrounded by
young cysts of spermatogonia. These younger spermatogonial
generations are larger cells and better for spermatogonial counts
than those in cysts more caudad. The cysts are clearly marked
off from one another by distinct walls. The spermatocytes
undergo considerable growth in size and their cytoplasm acquires
a large amount of mitochondria. The spermatocyte cysts occupy
by far the greater part of the tubules in nymphal males. At
no time during the growth period do the chromosomes disappear
or lose their staining powers. The transition from ultimate
spermatogonia to. the formation of the spermatids must be rather
slow, inasmuch as every stage in the conjugation of the chromo-
somes and the formation of the tetrads may be found in the
testes of a single nymph, previous to the final moult. This is
in marked contrast to many insects, in which the syndetic stages
are very rare and difficult to find. One fortunate condition in
the study of Anisolabis is the fact that each testicular tubule
contains a large number of cysts and that each cyst shows slight
variations in its meiotic phase.

238

SIDNEY I. KORNHAUSER

Many testes show a central core of heterogeneous material
made up of degenerating cysts. This looks much like the stream
of food seen passing from the terminal chamber to the growing
oocytes of telotrophic insect ovarioles. It is not the purpose
of the present paper to describe the details of the spermatogenesis
or the cytology of degeneration, although the author hopes to
attack these questions at another time.

The ovaries are composed of very long, and much attenuated
tubules, each fastened at its narrow, cephalic end by a terminal
filament reaching to the dorsal body wall. The sheath of each
ovariole is composed largely of tracheal tubules, and undergoes
rhythmic pulsations. The space between the egg string and this
sheath is filled with a coagulable fluid. The cephalic tip of each
ovariole, just caudad to the attachment of the terminal filament,
is occupied by a Keimpolster; then follow oogonia, showing an
occasional mitosis ; while a trifle more caudad one may find pairs
of oogonia both in the same mitotic phase. About one-tenth of a
millimeter from the Keimpolster occur the ultimate oogonial
mitoses. Here four cells all in the same stage of mitosis may be
found, and each cell gives rise to an oocyte and a nurse cell which
continue in close connection and accompany each other from
this time until the end of the growth period. Syndesis occurs
immediately after the differential mitosis, the oocyte here out-
stripping its sister nurse cell in size. Soon, however, the nurse
grows much larger than the oocyte, and, at about six-tenths of
a millimeter from the Keimpolster, they orient in single file
(oocyte, caudad; nurse cell, cephalad), acquire follicular walls,
and proceed in the accumulation of yolk material. The large
nurse cell with irregular nucleus is surpassed finally in size by
the o5cyte, and becomes a small cap on the cephalic end of the
ovum.

5. THE DIPLOID CHROMOSOMES

A, The female

Odgonia in their ultimate mitoses show 26 clear, distinct chro-
mosomes, well separated from one another. Numerous drawings
• were made and the number 26 established without doubt. Fig-

CYTOLOGY OF ANISOLABIS MARITIMA BON.

239

ures 1-4 (Plate XXIV) represent four typical metaphase plates.
Subsequent observations lead the author to believe that, of the
twenty-six chromosomes, twenty-two are autosomes, and four
are two double x-chromosomes, which appear in quiescent
oogonial nuclei as two double and almost square karyosomes.

The female somatic number has likewise been established
to be 26. The counts were made on well-developed embryos,
treated by the same methods as the gonads. Numerous mitoses
in the hypodermal cells and in the developing central nervous
system offered abundant material for statisfactory counts. A
suitable embryo would be selected and then sketches made of
every distinct metaphase plate in the whole series of sections.
Figures 5-8 (Plate XXIV) represent four groups showing 26
chromosomes each. These are selected from a single embryo in
which dozens of clear counts of 26 were made. In the somatic
cells, as has been noted by previous investigators, there is a
much greater variation in the size of the cells and the form of the
chromosomes (whether long and narrow, or short and broad) than
there is in the germ cells. The chromosome number, however,
remains constant, with the occasional exception of a giant cell
with twice the diploid number present.

B. The male

Spermatogonia likewise have clear, clean-cut chromosomes,
twenty-five in number, cells near the apex of the tubule serving
best for such counts. These spermatogonia have a large amount
of cytoplasm and the chromosomes are well separated (Plate
XXIV, figs. 9-12). In the cytoplasm onemay often encounter
bodies, which might be mistaken for chromosomes in deeply
stained haematoxylin preparations, especially after Bouin or sub-
limate fixation. In such preparations these cytoplasmic masses
are quite as dark in color as the chromosomes and not greatly dif-
ferent in size from the average Anisolabis chromosome. These
bodies are shown, light gray in tone, in figures' 9, 11, and 12 of
Plate XXIV. After Benda fixation these cytoplasmic bodies take
mitochondrial stains, and stand out in marked contrast to the

240

SIDNEY I. KOKNHAUSER

chromosomes, being purple in crystal violet + alizarin, and red
in methyl green + acid fuchsin. The use of these stains enables
one to establish the number twenty-five for the spermatogonial
chromosomes. As will be shown later, twenty-two of these are
autosomes, two form an x-complex, and one is a y-chromosome.

The male somatic number was likewise established by the study
of serial sections of embryos in which many counts of single
individuals were made. Figures 13 to 16 (Plate XXIV) are typical
25 chromosome plates of such male embryos. The following
important variation, the only characteristic one so far found in
the study of Anisolabis, must be noted. In male embryos, with
typical 25 chromosome cells, one finds clear metaphase plates
with only 24 chromosomes. This happened too often to be purely
accidental or due to error or oversight. A probable explanation
of the phenomenon will be given in Part 8.

6. THE SPERMATOCYTE CHROMOSOMES

The initial and most fundamental facts to be established were
that twelve chromatic elements were uniformly present in prim-
ary spermatocyte metaphase plates (Plate XXV, figs. 28-29), and
that half the secondary spermatocytes possessed twelve chromo-
somes and the other half had thirteen (Plate XXVI, figs. 44-47).
These facts made necessary the careful study of the origin of
the twelve primary spermatocyte chromosomes.

From the 25 spermatogonial chromosomes are formed eleven
autosomal tetrads and a heterochromosomal hexad, which I
have called the xxy-complex and which may be seen in figures
17-27 (Plate XXV). The autosomal threads and tetrad forma-
tion are omitted from these figures. The evidence is rather clear
that the tetrads are formed by parasyndesis, and it is hoped that
additional smear preparations will enable the author to deal
with this point in more detail in another paper. Figures 17-22
show merely the nuclear outline and the xxy-complex, stained in
iron-haematoxylin, the relative intensity of the stain being
depicted as accurately as possible in the figures.

Figure 17 is an early leptotene stage, the autosomal threads
just emerging from the telophase chromosomes of the ultimate

CYTOLOGY OF ANISOLABIS MARITIMA BON.

241

spermatogonial division. Here there is seen a double, rather
angular body (xx), and a deeply staining sphere (y). With the
establishment of the leptotene threads (Plate XXV, fig. 18), the
xx-and the y-element come into close apposition and remain
connected, sometimes merely by a small strand (Plate XXV,
figs. 19, 20), and also during syndesis they continue this connec-
tion. When the zygotene threads are well formed, the xx-
element separates from the y-element. Often they come to lie
at some distance from each other in the nucleus, but apparently
not under control of the centrosome at the positive pole of the
nucleus (Plate XXV, figs. 21, 22).

With the beginning of the strepsinema the xx-element and the
y-element again approach each other and are again connected
by a narrow strand (Plate XXV, figs. 23, 24). The xx-element
reveals its two-fold constitution, when viewed at a favorable
angle in well-decolorized haematoxylin preparations, and es-
pecially well in crystal violet + alizarin slides. At the establish-
ment of the strepsistene stage we notice the coalescence of the
xx-and the y-element. In iron-haematoxylin the y-element has
a lighter cortical zone, and a more deeply stained center. The
doubleness of the x-portion is no longer so distinct (Plate XXV,
figs. 25-26).

When the autosomal tetrads are formed, but are still very
granular, there appears on the xxy-complex a highly refractive
spherule (fig. 27, nl), which separates from its parent mass at
about the time the smooth, deeply staining tetrads are estab-
lished. This nucleolar body may then lie anywhere in the nucleus,
even in close appostion to one of the autosomal tetrads. As
the centrosome divides and preparation is made for the first matu-
ration spindle, this nucleolar body diminishes in size and finally
disappears, leaving eleven autosomal tetrads and the xxy-hexad
to enter the metaphase plate.

Not only form but also differential reaction to stains enables
one to trace the evolution of the hexad. In safranin + lichtgriin,
the y-element is not so deep a red as the xx-component, in stages
corresponding to those shown in figures 17-26. The y-element
also appears vacuolated, and has a greenish tinge in the early

242

SIDNEY I. KORNHAUSER

strepsinema. Finally in the later strepsistene stage, when the
chromatic spherule is given off, the y-element stains as deeply
as the two x-elements. In crystal violet + alizarin the y-element
is purple, and the xx-element brown with small purple granules
in it; whereas the nucleolar sphere of the late strepsinema is
deep purple. In methyl green + acid fuchsin, the y-element is
red, and the xx-element green. As the two fuse, in stages
corresponding to figures 25 and 26, the y-element gradually loses
its red color and becomes green, while the extruded nucleolar
spherule is a deep red. We must, I believe, assume that the
extrusion of this nucleolar spherule is in a vital way connected
with the change in ^^stainability’’ of the y-element.

The twelve chromosomes of the primary spermatocyte meta-
phase (Plate XXV, figs. 28, 29) are so widely separated that, in
lateral views with very high magnification, one may focus sharply
on each element in the spindle. Good lateral views of the xxy-
hexad may be obtained not only in metaphase plates (figs. 30-33)
but also in anaphase stages (Plate XXVI, figs. 37, 38). Figure
34 (Plate XXV) shows the twelve elements of the metaphase plate
viewed laterally, the chromosomes of the several foci being here
transposed into a single row from the camera lucida drawing.
The hexad is on the extreme right. Figure 35 represents a
corresponding stage, but taken from a smear slide. The contents
of the cell were so spread out that a single focus di^layed
all the chromosomes with no overlapping. In the smear slides
the chromatic elements appear smaller but retain all the features
seen in sections, and offer a very good check upon the latter.

The attachment of the y-element and the xx-element seems

y

XX

Various arrange-

to be either terminal x or lateral

l X J

ments of the elements taken from metaphases and anaphases are
seen in figures 30-38. Figure 36 (Plate XXV) shows seven
separate xxy-hexads, the y-element in all cases being uppermost
in the figures.

In the first meiotic division (Plate XXVI, figs. 37-41) the
y-chromosome passes to one pole and the double x-chromosome

CYTOLOGY OF ANISOLABIS MARITIMA BON.

243

to the other. Figures 40 and 41 represent two anaphase plates
of a single cell, similar to that shown in figure 39, but cut through
the equatorial zone so that one section contains one plate and the
next section its sister. In both plates eleven of the chromosomes,
the autosomes, are similar; and the large xx-element in figure 41
and the smaller y-element in figure 40 occupy corresponding
positions.

Following the telophase of the first meiotic division there is
a definite interkinetic period with the establishment of a well-
defined, nuclear membrane (Plate XXVI, fig. 42). The centro-
someof the primary spermatocyte telophase remains visible and
establishes the spindle of the secondary spermatocytes. The
dyads remain rather distinct, deeply staining, block-like masses
in the nucleus of the interkinetic stage.

With the formation of the secondary spermatocyte spindles
we now have two distinct types of metaphase plates: those
with twelve chromosomes, and those with thirteen (Plate XXVI,
figs. 43-47). The twelve chromosome plates consist of 11 dyads
and a y-chromosome. The thirteen chromosome plates consist
of 11 dyads and two x-chromosomes, which separated from each
other during the interkinetic period and are here represented by
two discrete elements. Figures 46 and 47 (Plate XXVI) show
two pairs of sister second spermatocytes, one in each pair con-
taining twelve, and the other thirteen chromosomes. The
former figure is taken from a section, the latter from a smear
slide.

Occasionally giant secondary spermatocytes are formed with
all the chromatic elements of the first maturation spindle present,
the chromosomes having divided but the cytoplasm having
failed to do so. Two such metaphase plates are shown in
figures 48 and 49 (Plate XXVI) and each has 25, well-defined
chromosomes.

The second maturation mitosis divides all the chromosomes
equationally, and they pass to their respective poles without
lagging. Figures 50 and 51 represent sister anaphase plates,
drawn from a smear slide, and showing an exact correspondence
in their chromatic elements. The spermatids (fig. 52) are formed

244

SIDNEY I. KORNHAUSER

immediately after the telophase of the second meitotic division
and bear a remarkable resemblance to the interkinetic spermato-
cytes, except that they are smaller and that their chromosomes
soon break up into granules.

7. DISCUSSION

The author believes the female diploid number of chromosomes
of Anisolabis to be twenty-six in both germ cells and soma
cells, as against twenty-four claimed by Randolph (’08) for both
sexes. The normal male diploid number is twenty-five although
somatic mitoses with twenty-four chromosomes are found.

The union of the two x-chromosomes into a single body is
probably the explanation of this last phenomenon, and this
supposition is strengthened by the fact that, in the growth of
the spermatocytes and in the first spermatocyte division, these
two x-elements of the xxy-hexad are in close apposition, leading
to the assumption that the two parts are intimately related.
The x-complex may be considered either as having originated
from a single x-chromosome or as now being in the process of
the formation of a single x-chromosome out of two previously
distinct chromatic elements.

Another view of the 24 chromosome somatic male cells is
possible: namely, that after a number of somatic divisions, the
y-element undergoes a dissolution. From the behavior of the
y-element in the growth of the spermatocytes, one may infer
that it is greatly different from the normal chromosomes; for,
not until the late strepsistene does it acquire a true chromatic
stain, when tested with alizarin crystal violet or with methyl
green +acid fuchsin. Only after giving off the nucleolar spherule,
which takes the mitochondrial stains deeply, does its definite
chromatic nature appear.

Our interest in the y-chromosome must be again kindled in
view of the recent type of inheritance described by Castle
(’21) linked with this exclusively paternal chromatic element.
We must try to determine whether the y-chromosome is a chromo-
some in a state of formation or whether it is merely a degenerate
x-chromosome.

CYTOLOGY OF ANISOLABIS MAKITIMA BON.

245

In regard to the sex-chromosome of the forficulids, the author
would maintain that in Anisolabis we have neither unpaired
accessory chromosomes, nor a pair of unequal heterochromo-
somes, nor a pair of almost equal heterochromosomes, as pre-
viously described by various authors. The following conditions
are believed to exist : the female diploid number is 26, consisting
of 22 autosomes and 4 x-chromosomes ; the female haploid number
(inferred) is 13, consisting of 11 autosomes and 2 x-chromosomes;
the male diploid number is 25, consisting of 22 autosomes, 2
x-chromosomes, and a y-chromosome; half the second spermato-
cytes show 13 chromosomes, and the other half 12. The former
gives rise to two female determining spermatozoa, containing
11 autosomes and 2 x-chromosomes; the latter gives rise to
two male determining spermatozoa, with 11 autosomes and a
y-chromosome.

It will be an interesting problem to see if the small mature
males, occasionally found in Anisolabis, are in some way related
to an upset in the normal chromosomal distribution described
above.

8. SUMMARY

1. The diploid number of chromosomes in Anisolabis is 26
in the female, and 25 in the male both in somatic and germinal
cells.

2. The only variation from the above is in the male somatic
cells, where only 24 chromatic elements may often be counted.
This may be due to a fusion of the two x-chromosomes in the
male cells or to the loss of the y-chromosome.

3. Primary spermatocytes show twelve chromosomes: eleven
are autosomal tetrads, and one an xxy-hexad.

4. The xx-element together with 11 autosomal dyads pass
into one secondary spermatocyte; the y-element and 11 autosomal
dyads pass into the sister cell.

5. In the interkinetic period the two x-chromosomes separate

and appear as discrete bodies in the second maturation spindle.
We therefore find 13 chromosomes in one half the metaphase
plates, and 12 chromosomes in the other half. --

246

SIDNEY I. KORNHAUSER

6. All chromosomes divide equationally in the second sper-
matocyte division, giving rise to female determining spermatozoa
with 11 autosomes and two x-chromosomes, and male determin-
ing spermatozoa with 11 autosomes and a y-chromosome.

7. The y-chromosome of the spermatocyte is chemically and
morphologically rather unlike the x-chromosomes during the
growth period up until the late strepsinema, when it gives off a
nucleolar spherule which takes mitochondrial stains.

Granville, Ohio, June 28, 1921,

9. BIBLIOGRAPHY

Brauns, Fr. 1912. Die Entstehung der Nahrzelle und die Bedeutung derselben
flir das wachsende ei bei Forficula auricularia L. ; Sitzungsb. u Abhandl.
d. naturf. Gesellsch., Rostock, N. F., Bd. 4 (245).

Castle, W. E. 1921. A New Type of Inheritance. Science, N. S., Vol. 53,
No. 1371, pp. 339-342.

Pantel, J. 1912. Recherches sur les Dipteres a Larves Entomobies. II. Les
enveloppes de Poeiif avec leurs dependances, des dcgats indirectes du
parasitisme. La Cellule, T. 29, Fasc. 1, pp. 7-289. PI. I-VII, 25 text
figs.

Payne, F. 1914. Chromosomal Variations and the Formation of the First
Spermatocyte Chromosomes in the European Earwig, Forficula sp.
Journ. Morph., Vol. 25 No. 4, pp. 559-581, PI. 2, text figs. 7.

Randolph, Harriet. 1908. On the Spermatogenesis of the Earwig Anisolabis
maritima. Biol. Bull., Vol. 15, No. 2, pp. 111-114.

Stevens, Nettie M. 1910. An Unequal Pair of Heterochromosomes in For-
ficula. Jour. Exp. ZooL, Vol. 8, No. 2, pp. 227-234, 3 pi.

ZwEiGER, H. 1906. Die Spermatogenese von Forficula auricularia L. Jena
Zeitschrift f. Natur. wiss., Bd. 42, pp. 143-169.

10. EXPLANATION OF PLATES

All drawings were made with the aid of a camera lucida. A 1.5 mm. Zeiss
apochromatic objective and a 20X compensating ocular was the optical combi-
nation used. All figures were drawn at 3300 diameters magnification and subse-
quently reduced, in Plate XXIV the reduction being about one-third and in
Plates XXV and XXVI the reduction being about two-fifths.

Plate XXIV

Figs. 1-4. Oogonia, metaphase plates, polar view, 26 chromosomes.

Figs. 5-8. Somatic mataphase plates, polar view from female embryo, 26
chromosomes.

Figs. 9-12. Spermatogonia, metaphase plates, polar view, 25 chromosomes.

Figs. 13-16. Somatic metaphase plates, polar view from male embryo, showing
25 chromosomes.

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE XXIV

KORNHAUSER: CYTOLOGY OF ANISOLABIS MARITIMA BON.

Plate XXV

Primary Spermatocytes

Fig. 17. Early leptotene nucleus, showing xx and y

Fig. 18. Trifle later stage than Fig. 17, xx and y in close apposition.

Figs. 19-20. Nuclei of syndetic cells, xx and y connected.

Figs. 21-22. Diplotene nuclei, showing separation of xx and y-elements.

Figs. 23-24. Early strepsistene nuclei, showing reunion of xx and y.

Figs. 25-26. Later strepsistene nuclei, showing fusion of xx and y.

Fig. 27. Late strepsistene, showing the formation of the nucleolar spherule
(nl)

Figs. 28-29. Primary spermatocytes, metaphase plates, polar view, showing
12 chromosomes.

Figs. 30-33. Primary speratocytes metaphase, lateral view, showing xxy-hexad

Fig. 34. The twelve chromosomes of a primary spermatocyte metaphase,
xxy on extreme right, taken from a section.

Fig. 35. Same stage as figure 34, except that it was taken from a smear slide.

Fig. 36. Various forms of the xxy-hexad, as seen in metaphases and anaphases
of primary spermatocytes viewed laterally, y-element shown above in each case.

Bulletin Scientific Laboratories Denison University Vol. X!X

PLATE XXV

KORNHAUSER: CYTOLOGY OF ANISOLABIS MARITIMA BON.

Plate XXVI

Figs. 37-38. Anaphases of primary spermatocytes, showing separation of xx
and y. In figure 37, the hexad is in linear arrangement; in figure 38, the two
x-chromosomes are placed side by side and the y-chromosoms is above.

Fig. 39. Late Anaphase of primary spermatocyte, the xx-element passing to
the upper pole in the figure.

Figs. 40-41. Sister anaphase plates of cell corresponding to figure 39. In
figure 40, the y-element is included; in figure 41, we see the xx-element.

Fig. 42. Interkinesis.

Fig. 43. Metaphase secondary spermatocyte, lateral view.

Fig. 44. Metaphase secondary spermatocyte, polar view, showing 13 chro-
mosomes.

Fig. 45. Metaphase secondary spermatocyte, polar view showing 12 chromo-
somes.

Fig. 46. Sister cells, secondary spermatocytes, metaphase, polar view^: one
showing 12, the other 13 chromosomes.

Fig. 47. Same stage as figure 46, but taken from a smear slide.

Figs. 48-49. Giant secondary spermatocytes, metaphase, polar view, showing
25 chromosomes

Figs. 50-51. Sister anaphase plates of a secondary spermatocyte (12 chromo-
some type), showing exact distribution of chromatin to spermatids.

Fig. 52. Spermatid, shortly after second meiotic division.

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE XXVI

KORNHAUSER: CYTOLOGY OF ANISOLABIS MARITIMA BON,

NOTES ON ARCTIC ORDOVICIAN AND SILURIAN
CEPHALOPODS

Chiefly fkom Boothia Felix — King William Land, Bache
Peninsula, and Bear Island

AUG. F. FOERSTE

To Dr. Olaf Holtedahl we owe a number of very valuable
papers bearing directly on American Arctic geology. In 1912
he published his paper ^^On Some Ordovician Fossils from
Boothia Felix and King William Land collected during the
Norwegian Expedition of the Gj0a, Captain Amundsen, through
the Northwest Passage’’ in the Videnskapsselskapets Skrifter,
I, Mat-naturv. Klasse, 1912, No. 9. The fossil material of
this expedition was collected by Lieutenant Godfred Hansen,
the second in command. The fossils forming the subject of
Dr. Holtedahl’s paper were collected at two localities. One of
these was at Cape Christian Frederick on the west coast of
Boothia Felix, Longitude 94° west and Latitude 69° 30' north,
where collecting was done in September 1903. The other was
somewhere on King William Land. It is known that in 1903
Hansen collected fossils on the Pfeffer River on King William
Land, about 20 miles west of Gj0a Harbor, where the expedition
had wintered. This harbor is on the south coast of King William
Land at Longitude 96° west. Unfortunately, on account of
inadequate labelling, it is impossible now to determine from which
of the two localities the various specimens under consideration
were obtained. The fossils were identified by Dr. Holtedahl as
Receptaculites oweni Hall, Halysites sp., Columnaria sp., with
partly separated corallites, Maclurites sp., Eurystomites sp.,
Actinoceras heloitense (Whitfield), Actinoceras sp. (cf. tenuifilum
Hall), and Gonioceras occidentale Hall (Holtedahl, Plate III.
fig. I). This is a Black River fauna. Judging from the promi-

247

248

AUG. F. FOERSTE

nence of the oblique lateral ribs toward the ventro-lateral angles
in the figure of the Eurystomites published by Dr. Holtedahl
(Holtedahl, Plate II, fig. 1), this Nautiloid is a Ptectoceras related
to such Black River forms as Plectoceras undatum (Conrad) and
Ptectoceras halli (Foord). The siphuncle of the specimen identi-
fied as Actinoceras heloitense (Whitfield) (Holtedahl, Plate IV,
fig. 2) appears to be too small for typical forms of that species.
The form figured as Actinoceras sp. cf. tenuifilum(B.Si\\) (Holte-
dahl, Plate III, fig. 2) was kindly loaned to the present writer by
Dr. Holtedahl, and is figured on Plate XXVI of the present paper.
It has shorter camerae and a smaller siphuncle than Actinoceras
tenuifilum, and probably belongs to a new species of which more
material is needed to discriminate it satisfactorily from other
forms.

In the specimen figured by Holtedahl as Endoceras {Cyclendo-
ceras) annulatum Hall (Holtedahl, Plate IV, fig. 1), the annula-
tions are much stronger and the number of camerae in a length
equal to the diameter of the conch is much less than in typical
forms of that species. Moreover, it does not present the strong
downward flexure of The annulations on the ventral side of the
conch characteristic of typical Cyclendoceras. Its * general
appearance is more like that of a Dawsonoceras^ but, in the
absence of any knowledge of its siphuncle, it is impossible to
state positively that it could not be a Cyclendoceras,

In addition Dr. Holtedahl loaned also a number of Actino-
ceroids, a part of which are here figured and described in the hope
that further material may be collected elucidating these forms.
One of these is named Actinoceras amundseni in honor of Captain
Roald Amundsen, the leader of the expedition. The material
forwarded includes also a peculiar orthocone, flattened on one
side, for which the new term Leurorthoceras hanseni is proposed
in honor of Lieutenant Godfred Hansen, the geologist of the
expedition and the second in command. It is regarded as a
new genus. The Actinoceroids and the species of Leurorthoceras
just mentioned are regarded as of Black River age.

In 1913 the same Videnskabs-selskabet of Kristiania published
Dr. Holtedahks paper on ^^The Cambro-Ordovician Beds of

AECTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 249

Bache Peninsula and the Neighboring Regions of Ellesmere
Land’’ in No. 28 of the Report on the Second Norwegian
Arctic Expedition in the ^^Fram” 1898-1902. This expedition
was led by Captain Otto Sverdrup; Per Schei was the geologist
of the expedition. Bache Peninsula lies between 79° and 79°16'
north latitude on the eastern coast of Ellesmereland and extends
as far eastward as 74° 30' west longitude. Cape Camperdown
forms its southeastern corner and Victoria Head its northeastern
corner. The lowest strata on the peninsula are exposed at
Cape Camperdown. From this locality Dr. Holtedahl figured
a cranidium, a free cheek, and a pygidium under the teriri Ptycho-
paria sp. The strata at Cape Camperdown dip north-north-
west and are overlaid stratigraphically by those at Victoria
Head.

From the Orthoceras limestone, ^‘a bed of light greyish- white
limestone, about 350 ft. thick which cropped out midway
up the vertical face of Cape Victoria Head,” Dr. Holtedahl
figured a cranidium of another Ptychoparia and a cranidium of
Illaenurus. In addition, sections of fossil fragments, especially
of Orthoceratidae, are fairly common. Of these Orthoceratidae
Dr. Holtedahl kindly loaned me a number of specimens. At
first sight these appeared to be very unpromising material,
consisting chiefly of fragments of conchs exposing oblique cross-
sections of their interiors. In most cases not even enough of
the conch is present even for generic determination. However,
in several cases, by grinding away the matrix, enough of single
conchs was revealed to admit of fairly detailed study. Two of
these specimens are figured and described here under the terms
Clarkoceras holtedahli and Ellesmeroceras scheii; the first is named
in honor of Dr. Holtedahl, to whose paleontological studies we
are indebted greatly in our knowledge of Arctic faunas, and the
second is named in honor of Per Schei whose zeal in collect-
ing made some of these paleontological studies posssible and
whose untimely death we mourn. The second species belongs
to the Endoceratidae, but is regarded as differing sufficiently from
typical Endoceras to warrant a distinct generic name. It has
its nearest relatives among Endoceratidae of Canadian age.

250

AUG. F. FOERSTE

Clarkoceras holtedahli is closely related to the genotype Clarko-
ceras newtonwinchelli (Clarke) from the Shakopee member of
the Canadian in Minnesota. A third specimen, here figured but
not described (Plate XXVII, figs. 4, A, B, C) , possibly may be an
Endoceratitic shell with a large siphuncle in contact with the
ventral wall of the conch, as in Cameroceras tenuiseptum (Hall),
but, in the absence of any definite knowledge of the siphuncle
in this Bache Peninsula specimen, its generic reference remains
impossible.

Dr. Holtedahl was inclined to regard the Orthoceras limestone
specimens figured by him as Cambrian. There is a possibility
of their being Ozarkian instead, lllaenurus convexus Whitfield
occurs in the Mendota member of the Ozarkian in Wisconsin
and several Ptychopariae occur in the Ozarkian of Point Levis,
in Quebec, and in the Potsdam of New York and in the Kittatinny
of New Jersey, of which the latter also are regarded as Ozarkian
by Ulrich. Possibly both Ozarkian and Canadian horizons are
represented in the Orthoceras limestone of Bache Peninsula,
since the cephalopods here described have a distinctly Canadian
appearance.

Above the Orthoceras limestone on Victoria Head is first a
series of sandstones alternating with limestones, and next a
^^bed of close-grained brown limestone, about 100 feet thick,
some of the layers of which are fossiliferous. ’’ From this brown
limestone Dr. Holtedahl figures a Hormotoma, a Maclurea, and
a Bathyuriscus. The genus Hormotoma is represented by num-
erous species in the Canadian. Maclurea also is represented
by a number of species in the Canadian of Newfoundland,
Vermont, and New York. If the pygidium figured from the
brown limestone could be referred to Bathyurus or Bathyurellus
instead of Bathyuriscus then again it would find numerous rela-
tives in the Canadian. It seems possible, therefore, to regard
the brown limestone in the upper part of the Victoria Head
section as of Canadian or even of post-Canadian age.

From Victoria Head, in his work on ^^Palaeontology of the
Coasts 'of the Arctic Lands’^ (Quarterly Journal of the Geol. Soc.
of London, Vol. 34, 1878), Etheridge reports the discovery of
Maclurea magna Leseur, a typical Chazyan fossil.

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 251

From Norman Lockyer Island, about 8 miles directly north
of Victoria Head, Dr. Holtedahl lists Haly sites gracilis (Hall),
Calapoecia canadensis Billings, Streptelasma corniculum Hall,
Mesotrypa cf. discoidea orientalis Bassler, Hallopora angularis
(Ulrich), Rafinesquina deltoidea (Conrad), Plectamhonites sericeus
(Sowerby), Orthis tricenaria Conrad, Triplecia sp., Rhynchotrema
inaequivalvis (Castelnau) , Trochonema umbilicatum (Hall) , Gonio-
ceras occidentale Hall, T'/iaZcops ovatus Conrad, N ileus {Bumas-
tusl) sp., and Leper ditiafahulites (Conrad) . This is a characteris-
tic Black River fauna, and is known to be wide spread in Arctic
areas.

The paleontological results of the voyage of the ^^Fram’^ in
the southwestern part of Ellesmereland were described by Dr.
Holtedahl in his paper ^^On the Fossil Faunas from Per Schei’s
Series B in Southwestern Ellesmereland,” which forms No. 32
of the series of Reports on the Second Norwegian Arctic Expedi-
tion in the ^^Fram” in 1898-1902, published by the Videnskabs-
Selskabet of Kristiania, in 1914. By far the greater part of this
report is concerned with the Helderbergian fauna of South-
western Ellesmereland, equivalent to the Keyser of Maryland;
however, lower faunas also are mentioned. Three Niagaran
species, Strophonella cf. euglypha (Hisinger), Conchidium arcticum
Holtedahl, and Ceraurus sp., are described from Baadkap, 30
miles southwest of the southwestern corner of Ellesmereland,
on the northern shore of North Devon. Three species, probably
of Black River age, are listed from South Cape, on the west side
of the mouth of Harbour (Havne) Fjord, on the south shore of
Ellesmereland, at 84° 30' west longitude; these species are Haly si-
tes cf. gracilis (Hall), Strophomena sp., and Maclurites sp. This
Black River horizon is underlaid by 1300 to 1600 feet of strata
consisting of limestone conglomerates with marly shales and
pure limestones which possibly correspond to the Canadian and
Ozarkian strata of the Bache Peninsula.

Dr. Holtedahl’s Notes on the Ordovician Fossils from Bear
Island collected during the Swedish Expeditions of 1898 and
1899,” published in 1918,. form No. 1 of volume V of the Norsk
Geologisk Tidsskrift. Bear Island is a small isolated island

252

AUG. F. FOERSTE

about two thirds of the distance from Norway to Spitzbergen. '
Here A. G. Nathorst collected in 1898 the bulk of the fossils
studied by Holtedahl. This was supplemented by material col-
lected in 1899 by J. G. Anderson, which, however, did not con-
tain much that was new. Both collections are deposited in the
Riksmuseet, at Stockholm, Sweden. These collections consist
of Black River fossils occurring in the upper part of the Heclahook
system in a series of strata known locally as the Tetradium
limestone. From this Tetradium limestone the following species
were listed: Tetradium cf. syringoporoides Ulrich, Bryozoa several
species, Crinoid stems, Rafinesquina sp., Orthoceras (Kionoceras)
sp. (Holtedahl, Plates XI, fig. 2), Endoceras (Vaginoceras) sp.
(Holtedahl, Plates X, fig. 1), Endoceras (Cyclendoceras) sp.
(Holtedahl, Plate IX, fig. 5), and Gonioceras {occidentale Hall?)
sp. (Holtedahl Plate XI, fig. 3) ; also various Actinoceroids
(Holtedahl, Plate X, figs. 2, 3, and Plate XI, fig. 1).

Regarding these species Dr. Holtedahl emphasizes the fact
that Tetradium and Gonioceras are typical American genera,
well represented in North America, while in Europe Tetradium
is listed only from the Borkholm in the Baltic area and Gonioceras
apparently does not occur at all. In Asia, moreover, Gonioceras
is known only at a single locality, in West Shantung in North
China, where it occurs associated with Actinoceras all. tenuifilum
Hall, another typical American Black River species. Regarding
Actinoceras, Dr. Holtedahl states that this genus may be said
to be characteristic of the American faunal province in Ordovician
times, while in Silurian times it has spread also to Europe and
is found quite commonly in England and in the Scandinavian-
Baltic regions. A true Actinoceras, somewhat resembling the
Silurian Actinoceras imhricatum Hisinger, is quite common in
the uppermost Ordovician of some districts at the western side
of the Kristiania region, in Hadeland and Ringerike. This
~ Norwegian occurrence possibly may indicate that the Actinoceras
stock came from the west or northwest in upper Ordovician times
and spread in Silurian times all over southern Norway and
Sweden.

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 253

During the summer of 1898 Dr. Holtedahl spent five weeks
on Bear Island. The results of his investigations were embodied
in his paper ‘ ^ On the Paleozoic Series of Bear Island, Especially,
on the Heclahook System/^ forming part II of volume. V of the
Norsk Geologisk Tidsskrift. In this paper he adds Maclurites
sp. and Gonioceras nathorsti Holtedahl (Holtedahl, Plate XIV,
fig.) to his former list of fossils from the Tetradium limestone of
Bear Island, figuring both species. In addition he figures a
vertical section of an Actinoceroid identified as Actinoceras
higsbyi Bronn (=A. tenuifilum Hall?) (Holtedahl, Plate XIII,
fig. 5) ; the latter is refigured in the present paper and the term
Actinoceras tenuifilum ursinum is proposed for it in allusion to
its occurrence on Bear Island. Moreover, for the species figured
in the preceding paper as Orthoceras (Kionoceras?) sp. (Holtedahl
Plate XI, fig. 2), the name Kionoceras holtedahli also is proposed
here.

However, the chief new feature of the second paper by Dr.
Holtedahl on the Geology of Bear Island is the proof which it
brings of the presence of Capadian strata on that island. These
species occur in the younger dolomite series of the Heclahook
System, beneath the Tetradium limestone horizons. The follow-
ing forms are listed: Calathium cf. pannosum BiWings, Calathium
sp., Archaeoscyphia {minganensis Billings?) sp., Crinoid stems,
Maclurites sp., Liospira sp., Lophospira sp., Orthoceras sp.,
Cyrtoceraconic shell, and Piloceras cf. explanator Whitfield
(Holtedahl, Plate XII, fig. 6; see also Plate XIII, fig. 3). The
significant genera of this list are Calathium, Archaeoscyphia^
and Piloceras-, which Dr. Holtedahl recognized not only as
characteristic of the Canadian but as having their main distribu-
tion in Newfoundland and in Eastern Canada.

In the present paper the species listed by Dr. Holtedahl as
Orthoceras sp. Holtedahl (Plate. XIII, fig. 1), is refigured as
Protocy cheer as cf. lamarcki (Billings), and the Cyrtoceraconic
shell of uncertain genus (Holtedahl Plate XIII, fig. 2) is refigured
under Deltoceras (?) sp., to indicate its Nautiloid character and
not because its genus is definitely known.

254

AUG. F. FOERSTE

On Bear Island the younger dolomite series of the Heclahook
system is underlaid by the slate-quartz series ^ and the latter
by the older dolomite series.. These older dolomite rocks contain
oolitoids and stromatolites, both chemical precipitates of car-
bonate of lime induced by the chemical activities of primitive
plants; some of the stromatolites are of the Cryptozoon type,
others are of the Gymnosolen type. The lower dolomitic rocks
are correlated with the Ozarkian of North America.

From these studies by Dr. Holtedahl it is evident that three
American series of Ordovician rocks had a wide distribution in
Arctic areas; these are the Ozarkian, Canadian, and Black River.
All three are recognized on Bear Island, and all three appear to
have their lithological equivalents on Spitzbergen. Moreover, the
two lower series appear to be represented also in Finmarken at
the extreme northern end of Norway. Here the Ozarkian or
older dolomite series of Bear Island is represented by the Por-
sanger series, and the Canadian or younger dolomite series of
Bear Island finds its equivalent in the Varanger and Raipas
series.

The Canadian age of the strata exposed at Durness, in the
extreme northwestern corner of Scotland, has been known for a
long time owing to the occurrence there of the very diagnostic
species Piloceras invaginatum Salter. Orthoceras'mendax Salter
is an annulated form with a relatively large subcentral siphuncle
which may turn out to be a Protocydoceras^ a typical Canadian
genus. Three species with very oblique annulations occur;
these are Orthoceras haculoides Blake, Orthoceras durinum Blake
and a form identified as Orthoceras arcuoliratum- (?) Hall. In
Orthoceras durinum the siphuncle probably is marginal. The
general aspect of these species is Canadian. If their siphuncles
were better known they probably would prove related to the
Endoceratidae rather than to the Orthoceratidae. Orthoceras
pertinens Blake, however, appears to be a typical Orthoceras,
Among other forms identified from the Durness limestone are
Ophileta compacta Salter and Maclurites matutinus (?) Hall,
both of which are typical Canadian forms.

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 255

The species listed by Wyatt-Edgell as Endoceras eoum and
described by Blake as Orthoceras {Conoceras) eoum, from , the
Arenig of Shelve, in the western part of Salop county, in Wales,
also has a Canadian aspect. The siphuncle is marginal and
equals two-sevenths of the diameter of the conch. On reaching
the siphuncle the septa ^^bend slightly upward toward the aper-
ture; though the chambers here stop short, the septa are con-
tinued over the siphuncle slightly bending upward, and along
the latter is a depressed line.” On the relationship of this
species Blake adds: ^‘This can not be an Endoceras, as the septa
certainly do not make sheaths pointing backwards.” Appar-
ently this shell bears some resemblance to Ellesmeroceras scheii
described in the present paper from Bache Peninsula.

Such species as Actinoceras cochleatum (Schlottheim) , Endo-
ceras festinans Blake, and the form identified as Endoceras
hrongniartii Troost suggest the Black River age of the Bala beds
of Great Britain. The Llandeilo fauna of the Girvan district
also contains American elements, such as Maclurites logani, a
typical American Black River form.

On continental Europe, however, in the Scandinavian-Baltic
areas, Ordovician faunas quite distinct from the American types
prevail, as though some barrier had intervened, forming an
eastern limit to the American Ordovician seas.

These conclusions are expressed by Dr. Holtedahl in the
following terms:

In the Bear Island a fauna occurs of which we can say that it is no
more closely connected with the Scandinavian-Esthonian than are the
American equivalent faunas themselves. In the writer’s opinion this
fact gets its most probable explanation by assuming a land barrier
between two different districts of sedimentation of middle Ordovician
time, the one characterized by an American-Arctic, the other by a
Scandinavian-Baltic faunal element. The many facts pointing towards
the existence — at a corresponding time — of a land mass to the north-
west of the northernmost, stiatigraphically more fully known districts
of Southern Norway and Sweden, the Mjosen district in Norway and
Jemtland of Sweden, support this supposition. In Scotland a land is
generally assumed to have been present in middle Ordovician time in

256

AUG. F. FOERSTE

the far northwest, while further to the southeast the marine Llandeilian
strata were deposited. Here we find the interesting Girvan deposits
in which certain American faunal elements can be traced.

Regarding the place of origin and the early centers of distribu-
tion of gasteropods and cephalopods Dr. Ulrich has submitted
the following observations :

The oldest, in eveiywise unquestionable, fossil record of the coiled
gasteropods and cephalopods is found in Ozarkian rocks. In fact these
classes constitute the most important parts of the middle and later
faunas of this period as developed in the Mississippi Valley. As but
few species of these classes are found elsewhere in rocks of this age, it
is assumed that the gasteropods and cephalopods originated in oceanic
basins to the south of the Mississippi embayment, that is in the Gulf
of Mexico, Caribbean Sea or South Atlantic. From there they spread
to the north and west, attaining before the close of the Canadian
period rather general distribution in the continental seas of North
America. However, judging from the Baltic section, they seem not
to have reached the European side of the Arctic until well into the
Ordovician (post-Canadian). About the same time, or perhaps in the
somewhat later Black River epoch, certain types of cephalopods, like
Gonioceras, spread from the Arctic into the Pacific. (Revision of the
Paleozoic Systems, Bull. Geol. Soc. America, 22, 1911, p. 503.)

Regarding the crinoids, Dr. Ulrich states:

The crinoids seem to have originated during the early Ordovician
(post-Canadian) in the southern middle Atlantic, where the dominant
types, as expressed in the invading Gulf faunas of this age are Dendro-
crinidae, Hybocrinidae, and Rhodocrinidae. During the Silurian the
Gotland crinoids, like the corals, spread freely through the Arctic and
then southward in America to northern Illinois. They extended also
southward into England, where a slightly different development
obtained, and thence into the Atlantic to the Gulf of Mexico and the
Mississippi embayment. All the succeeding Paleozoic crinoid faunas,
so far as known, originated in and spread from the Atlantic basins.
(Ibid., p. 502.)

Regarding the time of origin of the crinoids it is interesting to
note that, according to Dr. Holtedahl, fragments of silicified

AECTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 257

crinoid stems are common in the Canadian strata of Bear Island.
Moreover, fragments of crinoid stems are common also in some
of the rock specimens belonging to the Black River strata of
Bear Island.

In view of the wide distribution of Black River strata in Arctic
areas it is interesting to observe that only three species of crinoids
have been described so far from American Black River strata,
and all of these were found in the northern part of the Mississippi
embayment. These 3 species are Carabocrinus dicyclicus (Sarde-
son) from the Decorah of St. Paul, Minnesota, and of Ellsworth,
Wisconsin; Cremacrinus punctatus Ulrich from the Decorah of
Minneapolis, Minnesota; and Porocrinus pentagonius Meek and
Worthen from the Platteville of Dixon, Illinois. In the matrix
of the Black River strata in the Boothia Felix-King William
Land area and from the Cape Chidley area in northern Labrador,
only very depauperate stems of crinoids or cystids occur. Un-
fortunately it is not known on what basis the Bear island Cana-
dian and Black River stems were interpreted as crinoidal rather
than as cystidean. That cystidea are of much earlier origin
than crinoidea has long been known.

Among the Silurian faunas invading North America by way
of the Mississippi embayment are the Brassfield, typical St.
Clair, Osgood, Rochester, Waldron, and Brownsport, while the
Waukesha, Racine, Lockport, and Guelph represent invasions
from the north. (Ulrich, ibid., pp. 558-561). Regarding the
migration of Gotlandian faunas from Scandinavian-Baltic areas
across the Arctic into the Racine seas of Wisconsin and adjacent
Illinois, it is unfortunate that our knowledge of Niagaran faunas
in Arctic areas still is so inadequate. In my opinion, no equiva-
lent of a Gotlandian fauna has been recorded so far in American
Arctic regions.

From Oflley Island, at the mouth of Petermann’s Fjord on
the west coast of Greenland, at 81°16' north latitude, came the
forms described and figured by Foord as Orthoceras arcticum
Foord and Orthoceras darwini Billings. The first of these is a
cyrtoceraconic shell closely allied to an undescribed form in the
Racine of the Wisconsin area, while the second is the familiar

258

AUG. F. FOEESTE

Kionoceras myrice Hall and Whitfield from the Cedarville of
Ohio which is the Ohio equivalent of the Racine of Wisconsin.
Actinoceras backi Stokes was identified by Foord from Bessels
Bay, about 20 miles southwest of Offiey Island, and from Cape
Louis Napoleon, 120 miles southwest of Bessells Bay and 35
miles northeast of Bache Peninsula. Another Actinoceroid was
found at Dobbin Bay, directly west of Cape Louis Napoleon.

Trochoceras horeale Foord was described from Wellington
Channel, between North Devon and Cornwallis Islands. It
appears related to the Ordovician Eurystomites among the Tar-
phyceratidae, Orthoceras griffithi Haughton, a vertically striated
species, was described from Griffith’s Island, south of the middle
of Cornwallis Island. Endoceras ommaneyi Salter was described
from Assistance Bay, on the southern coast of Cornwallis Island.
According to Haughton it was a cyrtoceraconic shell.

Actinoceroids appear to be relatively common on Southampton
Island, which blocks the northern end of Hudson Bay, and
Actinoceroids are common also in the Silurian areas west of
Hudson and James Bays.

To me the affinities of these American Arctic cephalopods are
with American forms, especially of Racine and Drummond Island
type, and not with those of the Scandinavian-Baltic areas.
However, such a minute part of the great Arctic regions has
been investigated so far that it easily is possible for Silurian
zones of European facies to turn up elsewhere in Arctic areas
some time in the future. The vastness of these Arctic areas
may be realized from the fact that Greenland is as long as the
distance from Ottawa in Canada to Cuba; Baffin Land is as
long as the distance from Cincinnati, Ohio to Portland, Maine.
Ellesmereland is as long as the distance from Cincinnati to the
Gulf of Mexico. At least half a dozen of the lesser islands equal
in size at least two-thirds of that of the state of Ohio. Evidently
there are innumerable possibilities of future discoveries.

The present paper was inspired by Dr. Holtedahl’s extremely
important communications on the geology of various Arctic
areas, briefly reviewed on the preceding pages. While engaged
on the study of Arctic Ordovician and Silurian cephalopods the

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 259

writer has felt continually the necessity of bringing together
from various sources all available material for purposes of direct
comparison. In view of the extreme rarity of Arctic cephalopod
material, especially from some of the horizons and localities
studied by Dr. Holtedahl, the writer requested the loan of such
cephalopods as were at hand, and to the kindness of Dr. Holte-
dahl I owe the privilege of reexamining the material already
once worked over by him. While the following pages do not
add materially to the observations made by Dr. Holtedahl it is
hoped they may be of some service owing to more detailed descrip-
tion and additional illustrations of the cephalapods.

As will be noticed in the following descriptions, most of the
Arctic specimens here considered present sufficient detail to
be of interest, and yet fall short of furnishing enough evidence
for definite specific or, in a few cases, for generic reference.
The lack of definite knowledge of the relation of the siphuncle
to the cross-section of the conch in the Actinoceroids, and of
the structure of the siphuncle in the supposed Cydendoceroids^
is especially unfortunate. What here is attempted is to secure
all available evidence from such material as actually is at hand,
in the hope that sooner or later it may lead to the securing of
additional material. Such differences of opinion as here are
expressed are made possible by lack of sufficient evidence, and
evidently would disappear if more complete material could be
secured.

LIST OF SPECIES

Gasteropoda, Canadian

1. Cf. Euconia quebecensis Billings.

Cephalopoda, Canadian

2. Clarkoceras holtedahli Sp. nov.

3. Eremoceras syphax (Billings) ; type.

4. Ellesnierocei;^s scheii Gen. et Sp. nov.

5. Protocycloceras lamarcki (Billings) ; types

6. Protocycloceras whitfieldi Ruedemann .

7. Protocycloceras cf. lamarcki (Billings) ; Bear island form.

8. Deltoceras (?) sp.

9. Kionoceras laqueatum (Hall) ; type.

Black River and Trenton

10. Kionoceras holtedahli Sp. nov.

11. Kionoceras trentonense Sp. nov.

260

AUG. F. FOERSTE

12. Kionoceras sp.; from Trenton of Middleville, New York.

13. Kionoceras kentlandense Kindle and Breger.

14. Leurorthoceras hanseni Gen. et Sp. nov.

15. Leurorthoceras chidleyense Sp. nov.

16. Actinoceras tenuifilum (Hall) ; types.

17. Actinoceras sp. ; Boothia Felix-King William Land area.

18. Actinoceras amundseni Sp. nov.

19. Actinoceras sp.; HoltedahLs figured specimen.

20. Actinoceras sp. ; Boothia Felix-King William Land area.

21. Actinoceras tenuifilum centrale Var. nov.; New York.

22. Actinoceras cf. tenuifilum centrale; Boothia Felix-King William Land

area.

23. Actinoceras tenuifilum ursinum Var. nov.

24. Actinoceras parksi Sp. nov.

25. Cyclendoceras annulatum (Hall).

26. Cyclendoceras or Dawsonoceras.

Ordovician age uncertain.

27. Eurystomites (?) boreale Foord.

Helderbergian

28. Orthoceras sp.

1. Cf. Euconia (?) quebecensis (Billings)

Plate XXVII, fig. 1

Pleurotomaria quebecensis Billings, Pal. Foss. 1, Geol. Surv.
Canada, 1865, p. 190, fig. 174:

Pleurotomaria (Euconia?) quebecensis Bassler, Bibliographic
Index of Am. Ordovician and Silurian Fossils, 1915; gen. ref.

Height of shell 17 mm.; apical angle 62 degrees. Volutions
about 9, surrounding a deep conical umbilicus having an apical
angle of about 30 degrees. Vertical sections of the volutions
tend to have a trapezoidal outline. In these sections the outer
surface of each volution is moderately convex. The inner sur-
face, of each volution along the umbilicus, is very slightly convex
along its upper half, but along its lower half it^ is very strongly
convex curving strongly outward at its base. The line of con-
tact between successive volutions curves slightly downward
along most of its length but at its outer extremity there is a
slight tendency toward reversal of curvature. The shell is
very thin, but distinctly outlined in the matrix. The specimen
consists chiefly of a vertical section through the center of the

AECTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 261

spire, but at its base it exposes a short part of the length of the
two lower volutions.

Locality and Horizon. — From the Orthoceras limestone at
Victoria Head on Bache peninsula, in Ellesmer eland, west of
Smith Sound. The horizon is regarded as of Canadian age.
In the Palaeontologisk Museum, Kristiania, Norway. Collected
by Per Schei in May, 1899, on the Second Polar Voyage of the
^‘Fram’^ under Captain Sverdrup.

Remarks. — Since typical Euconia is of Canadian and Chazyan
age it would be interesting to discover this genus in the Orthoceras
limestone of Victoria Head. In its apical angle and in the large
size of its open umbilicus the species here figured and described
resembles the vertical section of Pleurotomaria {Euconia^.)
quehecensis figured by Billings, but here the resemblance ends.
The Victoria Head specimen has an extremely thin shell, there
is no trace of lines of growth or of a slit-band, and the inner
outline of the volutions is much more angular.

2. Clarkoceras holtedahli Sp. nov.

Plate XXVII, figs, 2A, B; Plate XXXIII, fig, 1

Specimen consisting chiefly of the upper part of the phragma-
cone; to this is attached that part of the basal portion of the
living chamber which is adj acent to the siphuncle. The phragma-
cone is estimated to have had a height of at least 60 mm.
The dorso-ventral diameter at the base of the living chamber
is estimated at 47 mm., and the dorso-ventral apical angle was
between 35 and 40 degrees. The conch is strongly compressed
laterally, the lateral diameter at the base of the living chamber
being, estimated at 25 mm. The conch is slightly curved length-
wise in a dorso-ventral direction. The location of the siphuncle
is endogastric, or on the concavely curved side of the conch.
Here the curvature equals about 1 mm. in a length of 25 mm.
The opposite side of the conch is curved in a convex direction,
apparently at about the same rate as the concavely curved side.

Five camerae occupy a length of 16 mm., measured along the
lateral side of the specimen; 2 additional camerae of about the

262

AUG. F. FOERSTE

same height are exposed in the vertical section exposing the
siphuncle; this is followed by a shorter camera, and a trace of
a second shorter camera. From this it is concluded that the
conch was mature. The sutures of the septa are directly trans-
verse to the axial diameter of the conch. At the base of the
specimen the dorso-ventral curvature of the septum has a radius
of 25 mm., and its radius of lateral curvature is scarcely 12 mm.
The siphuncle is almost in contact with the adjacent wall of the
conch. At the base of the living chamber the dorso-ventral
diameter of the siphuncle is about 7 mm. , or about one-seventh
of the dorso-ventral diameter of the conch. At the base of the
specimen the dorso-ventral diameter of the siphuncle is slightly
over 4 mm. The segments of the siphuncle intercepted between
successive septa present slightly concave vertical sections along
their walls. The lower margin of one segment invaginates into
the upper part of the segment next beneath. The thickness
of the siphonal wall is greater than that of the septa. There is
no trace of an endocone.

Locality and Horizon. — From the Orthoceras limestone on
Victoria Head, at the northeastern angle of Bache Peninsula;
regarded as of Canadian age. Collected by Per Shei in May,
1899. Deposited in the Palaeontologisk Museum, Kristiania,
Norway.

Remarks. — This species almost certainly is congeneric with
Clarkoceras newton-winchelli (Clarke), although it has not been
possible to prove that the segments of the siphuncle are annular
connecting rings, and not prolongations of the septal funnels as
in the Endoceratidae. In Cyrtoc^rina the interior of the siphuncle
has transverse ridges alternating with the septa between the
camerae. I do not know the structure of Cyrtocerina well enough
to determine whether this appearance of internal transverse
ridges indicates a structure generically different from that of
Clarkoceras. In such specimens of Cyrtocerina as I have seen
only the casts of the interiors of the camerae have been retained,
the substance of the siphuncle having disappeared.

Clarkoceras newton-winchelli is from the Shakopee division of
the Canadian in Union township in Houston county, Minnesota.

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 263

The type of Cyrtocerina, namely Cyrtocerina typica, is from the
Leray division of the Black River at Pauquette Rapids, on the
Ottawa River, in Canada, A second species, Cyrtocerina mer-
curius, was described by Billings from the Levis division of the
Canadian at Point Levis, in Quebec, Canada. A third species,
now known as Cyrtocerina madisonensis , was described by Miller
from the Saluda member of the Richmond at Madison, Indiana,
and a fourth species, Cyrtocerina (?) schoolcrafti, was described
by Clarke from the Decorah division of the Black River near
Cannon Falls, Minnesota. It is not certain that all of these are
congeneric.

Among all these species, the relationship of the Victoria Head
species described above, under the name Clarkoceras holtedahlij.
appears nearest to the Canadian genotype, Clarkoceras newton-
winchelli, thus favoring the Canadian age of the enclosing strata
at Victoria Head.

3. Eremoceras syphax (Billings)

Plate XXXIII j figs, 8 Aj B, C; fig, 2

Cyrtoceras syphax Billings, Pal. Foss., 1, Geol. Surv. Canada,
1865, p. 194, text fig. 178.

Eremoceras syphax Hyatt, Proc. Boston Soc. Nat. Hist.,
22, 1884, p. 282, Genotype.

Type specimen. — Conch slightly curved lengthwise along its
dorsal side, the radius of convex curvature of the latter being
about 100 mm. The ventral side is either straight or too faintly
concave to be measured for curvature, at least in the type speci-
men. This specimen consists of the living chamber with 11
camerae and part of a twelfth camera still attached. The height
of the living chamber is 18 mm. along its dorsal side; the margin
of the aperture slopes gently downward from the dorsal toward
the ventral side, so that the height of the living chamber along its
ventral side is estimated at about 15 mm. The upper part of the
shell of the living chamber is thickened slightly interiorly for a
distance of 8 mm. from the aperture. On the cast of the interior
of this chamber this thickening of the shell is indicated by a
slight constriction of the upper part of the cast.

264

AUG. F. FOEESTE

The conch is compressed laterally, the lateral diameter at the
aperture being 19 mm., the dorso-ventral one being estimated
at 23 mm. The corresponding diameters at the base of the living
chamber are 16 and 19 mm. respectively. The lower 9 camerae
occupy a length of 14 mm.; the upper 3 camerae, however,
occupy a length of only 3.8 mm., each being successively shorter
and the uppermost being only 1 mm. in length, thus indicating
that the specimen was mature.

Along the dorsal side of the conch the sutures of the septa are
almost directly transverse. On the lateral sides they curve at
first gently downward, and then, on approaching the siphuncle,
the sutures rise strongly upward. The septa, as far as known,
are only moderately concave. The siphuncle has a lateral apical
angle of 15 degrees. At the base of the living chamber its
lateral diameter is 7 mm. At the base of the specimen its lateral
diameter is 2 mm. The original length of the phragmacone of
a complete specimen may have been 20 mm. The ventral side
of the siphuncle apparently was in contact with the ventral
wall of the conch along almost its entire width, thus agreeing
with the latter in its lateral curvature. Along the side facing
the interior of the conch, the siphuncle was more convex laterally,
so that the cross-section of the siphuncle must have resembled
somewhat that of a Tripteroceras, in the flattening of one side
and the greater convexity of the opposite side. Between suc-
cessive septa the walls of the siphuncle curve slightly inward,
suggesting an Endoceratitic structure, successive funnels extend-
ing downward the length of one camera and invaginating into
the neck of the funnel next beneath.

The cast of the interior of the conch is marked by faint vertical
ribs, both on the phragmacone and on the living chamber, there
being possibly 35 or 40 ribs within the circumference of the living
chamber. Along the living chamber there are also several very
faint annulations, with crests about 3 mm. apart. These annula-
tions slope downward from the dorsal toward the ventral side
of the conch at an angle agreeing with that of the margin of the
aperture, but at a rate greater than that of the sutures of the
septa. Whether these very obscure vertical ribs and transverse

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 265

annulations indicate corresponding markings on the exterior of
the shell is unknown.

Locality and Horizon. — Found at Point Levis, Quebec, in the
Levis representative of the Canadian formation. Type, num-
bered 819, in the collections of the Geological Survey of Canada.

Remarks.- — The preceding description of the type of Eremo-
ceras syphax differs necessarily from those previously presented,
since only the dorsal side was exposed when the specimen was
studied by Billings and Hyatt. Recently, however, the writer
removed all of the surrounding matrix, thus exposing for the
first time the large siphuncle. What formerly had been regarded
as the siphuncle apparently was a slight discoloration along the
median line of the dorsal side, and this had been emphasized
by vertical scratches made in an attempt to learn more of the
supposed siphuncle.

4. Ellesmeroceras scheii Gen et. Sp. nov.

Plate XXVII, figs, 3 A, B, C; Plate XXXIII, fig. 3

Conch straight along the ventral side and presumably straight
also along the dorsal side as far as may be determined from the
specimen at hand. Apical angle small, probably about 8 degrees
in a dorso-ventral direction. Conch compressed laterally. At
the base of the living chamber the dorso-ventral diameter is
estimated at 12 mm.; the lateral diameter is 10.5 mm.

The number of camerae in a length equal to the dorso-ventral
diameter of the conch at the top of the series of camerae being
counted is 10. Since the uppermost camera has about the
same length as the camerae immediately beneath, it is not cer-
tain that the conch is mature. The sutures of the septa slope
from the siphuncle along the median line of the ventral side
downward toward the dorsal side, curving in a slightly sigmoid
manner. Along the middle of the lateral sides of the conch the
sutures form an angle of about 80 degrees with the vertical
axis; toward the siphuncle the sutures rise more rapidly and
toward the dorsal side of the conch they descend more rapidly
than along the middle of the lateral sides.

266

AUG. F. FOERSTE

The siphuncle is narrow and is in contact with the ventral
wall of the conch; apparently it is slightly flattened by its con-
tact with the latter. At the base of the specimen, where the
diameter of the conch is estimated at 9 mm., the diameter of
the siphuncle is about 1.4 mm. in a lateral direction. Laterally
the segments of the siphuncle present slightly concave vertical
outlines. If these segments represent downward continuations
of the septal necks, then the latter descend the length of a single
camera and they invaginate into the top of the septal necks
next beneath. No trace of surface ornamentation is preserved.

Locality and Horizon. — From the Orthoceras limestone at
Victoria Head on Bache peninsula, on Ellesmer eland, west of
Smith Sound. Regarded as of Canadian age. In the Pal-
aeontologisk Museum, Kristiania, Norway. Collected by Per
Schei in May, 1899.

• Remarks. — The species here described as Ellesmer oceras
scheii has about the same apical angle as Endoceras montrealense
(Billings) as figured by Ruedemann (Bull. New York State
Museum, 1906, p. 424, pi. 9, fig. 8); the number of its camerae
is also about the same, but in the latter species the sutures of the
septa curve distinctly downward on approaching the siphuncle
along the median part of the ventral side of the conch, and the
relative size of the siphuncle is much greater.

In the upward curvature of the sutures of the septa on approach-
ing the siphuncle Ellesmer oceras scheii resembles. Eremoceras
syphax but the apical angle of the latter is much greater, its
form is slightly cyrtoceraconic due chiefly to lengthwise curva-
ture along the dorsal side, and the siphuncle is much larger,
tapers much more rapidly toward its apical end, and is appressed
for a greater part of its width against the ventral wall of the
conch.

Ellesmeroceras is regarded as a straight Endoceratitic shell
with a relatively small siphuncle; the sutures rise on approaching
the siphuncle, and the latter is in contact with the ventral wall
of the conch. In true Endoceras the sutures do not rise in a
conspicuous manner on approaching the siphuncle but are more
nearly directly transverse. While I am doubtful as to the gen-

AECTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 267

eric value of the differences noted above, the Ellesmereland
specimen here described does not appear to me to be a typical
Endoceras; the absence of any trace of endocones is certainly
generic, if constant; hence the new generic term Ellesmeroceras,
with Ellesmeroceras scheii as the genotype is here proposed.

Conchs with siphuncles in contact with the ventral wall are
fairly common in the Canadian strata of eastern Canada and
in the adjacent parts of the United States. Most of these forms
are smooth but some are annulated. Most species are straight
but curved forms also occur. Among smooth forms with
relatively small siphuncles may be mentioned the species des-
cribed by Billings as Orthoceras cato, 0. repens, and 0. perseus.
The latter is laterally compressed. Orthoceras sordidum may
belong here also. In Orthoceras autolycus the conch is slightly
curved lengthwise.

Conchs with siphuncles in contact with the ventral wall occur
also in the Ozarkian but most of these are more or less distinctly
curved lengthwise.

The number of these early cephalopods in which the segments
of the siphuncle show concave lateral outlines also is of interest.
This type of outline is noted in Eremoceras syphax and Elles-
meroceras scheii. It is seen also in Cyclostomiceras cassinense
(Whitfield). It is figured by Ruedemann in Orygoceras cornu-
oryx (Whitfield), Protocycloceras whitfieldi Ruedemann, and
Endoceras montrealense (Billings). It was noted by Billings in
the species described by him as Orthoceras menelaus, Orthoceras
indegator, and Orthoceras flavins, the last two of which have
the siphuncle in contact with the ventral wall, as in Endoceras
montrealense. The number of such Canadian and Ozarkian
cephalopoda with siphuncular segments presenting vertical
lateral outlines is considerably multiplied if cyrtoceraconic forms
be included. This type of outline appears to occur chiefly in
Holochoanitic forms, but a reexamination of all forms having
this type of siphuncle is necessary.

As far as can be determined from the preceding observations,
the occurrence of Clarkoceras holtedahli and Ellesmeroceras
scheii in the Orthoceras limestone at Victoria Head suggests that
this limestone includes a horizon of Canadian age.

268

AUG. F. FOERSTE

Holtedahl, in his paper on ^^The Cambro-Ordovician Beds of
Bache Peninsula/’ figures fossils from three horizons. From
the sandstones at Cape Camperdown, at the southeastern corner
of Bache peninsula, he figures a cranidium, a free cheek, and a
pygidium of Ptychoparia. From an overlying light greyish-
white limestone which crops out midway up the vertical face of
Victoria Head he figures a cranidium of Illaenurus and one of
Ptychoparia. From an overlying close-grained brown limestone
farther up the Head he figures a pygidium of Bathyuriscus, a
Maclurea, and a Hormotoma. The Clarkoceras and Ellesmero-
ceras here described were obtained somewhere within the greyish-
white limestone mentioned above. Since the total thickness of
the latter was estimated by Per Schei at 350 feet, it is possible
that more than one horizon here is included. The Illaenurus
and Ptychoparia figured by Holtedahl suggest the Ozarkian age
of the including strata, while the cephalopods here discussed
suggest Canadian age. It is possible that both horizons are
present in the greyish- white limestone at Victoria Head.

5. Protocycloceras lamarcki (Billings).

Plate XXXIII, figs. 7 A, B, C, D

Orthoceras lamarcki Billings, Canadian Nat. Geol., 4, 1859,
p. 362; Geol. Canada, Geol. Surv. Canada, 1863, p. 121, figs.
38 a, b, c; Pal. Foss. 1, Geol. Surv. Canada, 1865, pp. 255, 347,
fig. 336.

Protocycloceras lamarcki Hyatt, Zittel-Eastman Textb. Pah
1, 1900, p. 518; Ruedemann, Bull. New York State Mus., 90,
1906, p. 441, pi. 15, figs.1-6; pi. 16, figs. 1, 2; figs. 15, 16.

Types. — The first published figure consists of three views of a
specimen numbered 550 in the collections of the Geological
Survey of Canada, and labelled as coming from lot 12, concession
12, Godmanchester township, in Huntingdon county, Quebec.
This specimen is 36 mm. long and has 12 annulations in a
length of 33 mm. ; the diameter at its upper end is 17 mm. ; and
its apical angle is about 8 degrees. In preparing the first pub-
lished figure a mirror camera lucida was used so that in both

AECTIC ORDOVICIAN AND SILURIAN CEPHALOPODS. 269

figure 38a and figure 38b the direction of lengthwise curvature is
opposite to that of the specimen itself. The latter consists of
part of a phragmacone, exposing on one side the septa, which are
only moderately concave. The sutures occupy the grooves
between the annulations, the latter occurring at mid-height of
the camerae. The siphuncle is relatively large, having a diame-
ter of 6 mm. at the top of the specimen, where the diameter of
the conch is 17 mm.

The second specimen figured by Billings, numbered 7455a
in the collections of the Geological Survey of Canada, was ob-
tained in Oxford township, in Greenville county, Quebec. In
a length of 57 mm. it contains 20 annulations. The diameter
at the top of the specimen is 18 mm.; here the diameter of the
siphuncle is 7.2 mm. ; and the center of the siphuncle is 8 mm.
from the nearest wall of the conch, so that its location is only
slightly excentric. In specimen 7456b, from the same locality,
the center of the siphuncle is four-elevenths of. the diameter of
the conch from its nearest wall, thus indicating a greater amount
of excentricity. Specimen 7456 consists of a phragmacone 110
mm. long, with an estimated diameter of 23 at the larger end.
Full grown specimens probably attained diameters of at least
30 mm.

Specimen 550b, from the same locality as the first figured
specimen, apparently has funnels descending for at least the
depth of one camera.

Specimens 508 and 508a, from Romaine on the Gulf of St.
Lawrence, apparently indicate obscurely that the lower end
of each funnel is inserted for a short distance into the top of
the funnel next beneath.

Locality and Horizon. — Found in various counties in the eas-
tern part of the province of Quebec, and on the Mingan islands
and on Newfoundland, in the Canadian formation. Also in
the Beekmantown of New York.

270

AUG. F. FOERSTE

6. Protocycloceras whitfieldi Ruedemann

Plate XXXIII, fig, 4

Orthoceras bilineatum, Whitfield, Bull. Amer. Mus. Nat.
Hist., 3, 1890, p. 35, pi. 2, fig. 5, fig. 17 a, b,

Protocycloceras whitfieldi Ruedemann, Bull. New York
State Mus. Nat. Hist., 90, 1906, p. 443, fig. 17a, pi. 15, fig. 7.

In a specimen of Protocycloceras whitfieldi Ruedemann, from
the Fort Cassin beds at Fort Cassin, Vermont, the structure of
the siphuncle is more distinctly shown. At the septal neck of
the funnel, the latter bends abruptly downward; the funnel
contracts downward in one specimen from a diameter of 7 mm.
at the neck to 6.3 mm. a little below the middle of the camera
beneath, expanding to 6.5 mm. at its lower margin, which de-
scends for a distance equalling about one-fourth of the height of
a camera into the upper part of the funnel next beneath. In
longitudinal sections, the siphuncle appears broadly annulated
at the septa, with very shallow intermediate grooves which have
their maxima of contraction slightly beneath mid-height of the
camerae. No distinct markings were noticed on the surface
of either Protocycloceras whitfieldi or of Protocycloceras lamarcki,

7. Protocycloceras cf. lamarcki (Billings)

Plate XXVII, fig. 5; Plate XXXIII, fig. 5A, B

Orthoceras ? sp., Holtedahl, Paleozoic Series of Bear Island,
1919, p. 129, pi. 13, fig. 1.

Conch enlarging very slowly, from 13.3 mm. to 14.6 mm. in
a length of 18 mm. The lower 4 camerae occupy a length of 10
mm.; and the upper 5 camerae, of 14 mm. The sutures are
assumed to have been directly transverse though they are not
exposed for a sufficient distance around the circumference of the
conch to permit the determination of their course with exact-
ness. The septa are moderately concave, curving downward
a distance of 2 mm. where their diameter is 14 mm. The siph-
uncle is relatively large, being 5 mm. in diameter where the
diameter of the conch is 14.5 mm. The position of the siphuncle

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 271

is nearly central, one side being 4.5 mm. from the nearest wall
of the conch while the other side is 5 mm. distant from the
opposite wall. Within each camera the enclosed segment of
the siphuncle appears to become narrower in a downward direc-
tion, curving slightly inward so as to present slightly concave
vertical outlines. Apparently the lower margin of each segment
of the siphuncle invaginates into the top of the septal neck next
beneath. Apparently also the surface of the shell is slightly
annulated, the crests of the annulations coinciding with mid-
height of the earner ae.

Locality and Horizon. — Collected 1 kilometer west of Norsk-
havna, or 1.4 kilometers north-north-west of the northern margin
of South Harbor on Bear Island, July 1918, by Olaf Holtedahl.
In the Palaeontologisk Museum, Kristiania, Norway. Original
of Fig. 1 on plate 11 of Holtedahrs paper on the Paleozoic Systems
of Bear Island. From the younger dolomite series, in the Hecla-
hook System of strata, corresponding to the Canadian of North
America.

Remarks. — The specimen from Bear Island is too poorly
preserved for exact determination, but its annulation, though
slight, and its large sub central siphuncle with segments narrow-
ing in a downward direction suggest affinities vj\i\iProtocycloceras
lamarcki. At least the resemblance is sufficient to suggest the
Canadian age of the enclosing strata on Bear Island. The
original identification of these Bear Island strata as Canadian
was based by Holtedahl on the association in the same strata
of such characteristic genera as Calathium, Archaeoscyphia, and
Piloceras. The Bear Island Calathium resembles Calathium
pannosum Billings, an Ozarkian species from Point Levis,
Quebec, and the Piloceras is closely related to Piloceras explana-
tor Whitfield from the Beekmantown member of the Canadian
in Vermont and New York. Archaeoscyphia is listed from the
Canadian of the Mingan Islands, in Canada.

272

AUG. F. FOERSTE

8. Deltoceras (?) sp.

Plate XXVII, fig. 6; Plate XXXIII, figs. 6 A, B, C

Cyrtoceraconic shell of uncertain genus, Holtedahl, Paleozoic
Series of Bear Island, 1919, p. 130, p. 13, fig. 2.

Nautiloid shell, with volutions strongly compressed laterally,
the dorso-ventral diameter of the specimen being 33 mm.; and
the lateral diameter 20 mm. The siphuncle is cylindrical in
form and slightly over 3 mm. in diameter; its center is 5.5 mm.
from the ventral wall of the volution. That part of the siphuncle
which is exposed in the specinien is crossed at mid-length by a
single complete septum having a concave curvature of about 7
mm. The ventral fourth of another septum is preserved 10
mm. from the first septum, on its orad side. Owing to the angle
at which this part of the specimen has been cut, the passage of
the siphuncle through this second septum is not retained. A
third septum is exposed on the apical side of the first mentioned
septum, at a distance of 11 mm. from the latter. This third
septum is the one exposed in the figure presented by Holtedahl,
cited above. Judging from the small curvature of the siphuncle
and of the ventral wall of the specimen at hand, the complete
phragmacone could easily have equalled 150 mm. in diameter
measured across the volutions, and the complete shell probably
was considerably larger.

From the curvature of the septum at the apical end of the
specimen it is evident that the sutures of the septa had broad
lateral lobes and also dorsal and ventral saddles; the general
appearance of the saddles must have been affected by the strong
lateral compression of the conch. It can not be determined
definitely from the small fragment at hand whether the specimen
was transversely ribbed or not, but it is assumed that no pro-
nounced ribbing was present. MoreoverV there is no evidence
of an impressed zone along the dorsal side of the specimen due
to contact with the ventral side of preceding volutions.

Locality and Horizon. — Collected 1 kilometer west of Norsk-
havna, or 1.4 kilometers NNW of the northern margin of South
Harbor, on Bear Island, by Olaf Holtedahl, in July, 1918. Depos-

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 273

ited in the Palaeontologisk Museum at Kristiania. Original
of fig. 2 on plate 13 of Holtedahl’s papery cited above. From
the younger Dolomite series, in the Heclahook System of
strata, corresponding to the Canadian of North America.

From such a small fragment it is impossible to determine
with confidence the generic relationship of this species, but it
evidently belongs to the Tarphyceratidae,

9. Kionoceras laqueatum (Hall)

Orthoceras laqueatum Hall, Pal. New York, 1, 1847, p. 13,
pi. 3, fig. 12.

Type. — Apical angle about 9 degrees. Diameter at the top
of the specimen estimated at 9 mm. In a letter Dr. Ruede-
mann states regarding this specimen that ^^The Orthoceras
laqueatum shows 11 vertical ribs on the visible half. Since
that is not quite the entire half, I should judge there were 20 ribs
on the shell. There is always one stria between two ribs’
Nothing is known of its interior structure.

Locality and Horizon. — From some unknown locality in the
Beekmantown division of the Canadian in New York state.
Hall stated that ^Hhe position of the specimen is probably at
the upper termination of this (Beekmantown) rock, and just
at its passage into the succeeding limestone.’’ The type is
numbered 12375 in the New York State Museum of Natural
History at Albany, New York.

Remarks. — The reference of this specimen to Kionoceras
must be regarded as tentative. If Kionoceras arose from a
multistriate ancestral Orthoceroid by the increased prominence
of certain of the vertical striae, then Orthoceras laqueatum may
be regarded as ancestral to typical Kionoceras.

10. Kionoceras holtedahli Sp. nov.

Orthoceras (Kionoceras?) sp. Holtedahl, Ordovician Fossils
from Bear Island, 1918, p. 84, pi. 11, fig. 2.

Judging from the figure published by Holtedahl, the apical
angle of the conch is about 4.5 degrees, and the number of verti-

274

AUG. F. FOERSTE

cal ribs is somewhere near 32 ; about 4 camerae appear to occupy
a length equal to the diameter of the conch at the top of the
series of camerae being counted, but Holtedahl states that the
distance between the septa is one-fifth of the diameter of the
shell. The vertical section of the lower end of the specimen,
as figured by Holtedahl, indicates that the segments of the siph-
uncle are almost globular, that the diameter of the siphuncle
equals almost one-fourth of that of the conch, and that its center
is about one-third of the diameter of the conch from its ventral
wall. In describing the ornamentation on the surface of the
shell Holtedahl states that the ‘ Tongitudinal ridges, though not
much elevated, have a rather sharp section. In some places
there seems to be present a faint ridge in the middle of the inter-
val between the ridges and possibly an indication of other,
extremely faint ones.’’

Locality and Horizon. — From the Antarctic Mountain area
in the southern part of Bear Island. From the Tetradium
limestone at the top of the Heclahook system. This limestone
is regarded as of Black River age. In the Riksmuseet, Stock-
holm, Sweden.

Remarks. — At least two undoubted specimens of Kionoceras
occur in strata below the Richmond in American areas, namely
Kionoceras kentlandense from the Black River area in north-
western Indiana and a lower Trenton form from New York
described by Hall under Orthoceras laqueatum ? var. a. Three
other species, typical Orthoceras laqueatum from the Beekman-
town of New York, a similar species from the Leray at Pauquette
Rapids, Canada, and the specimen here described as Kionoceras
trentonense from the middle Trenton at Middleville, New York,
may belong to the vertically striated forms from which Kionoceras
originated. Foord refers to Orthoceras laqueatum some imper-
fectly preserved specimens from the Trenton at Montmorenci
Falls, near Quebec, Canada which show ^Traces of what would
appear to have been longitudinal ridges.” It is cited also from
the Trenton at Frobisher Bay, on Baffin Land.

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 275

11. Kionoceras trentonense Sp. nov.

Plate XXXF, fig, 1

, Orthoceras laqueatum (Hall), Pal. New York, 1, 1847, p.
206, pi. 56, figs. 2 b, c.

Apical angle about 3 degrees. Diameter at top of specimen
estimated at 5 mm. Length of specimen 22 mm. At the smaller
end of the specimen a septum terminates the specimen. That
part of the specimen which in Hall’s figure extended beneath
this septum consisted of nothing but matrix. The siphuncle,
at its passage through the septum, is small and slightly excentric
in position. The surface of the shell is occupied by about 20
primary vertical ribs and an equal number of almost equally
prominent secondary riblets which alternate with the primary
ones. Both ribs and riblets rise acutely above the general sur-
face of the shell. In the grooves between the ribs and riblets
there are additional and much finer striae, usually 3, sometimes
4 or 5 in number, and visible only under a lens. Finally, the
microscope reveals numerous very fine transverse striae, about
70 in a length of 1 mm. These striae are horizontal along the
left third of the exposed part of the shell, they curve rather
strongly downward along the middle third and become horizontal
again along the right third. It is assumed that the right third
of the exposed part of the shell is the ventral side, and that there
was a distinct hyponomic sinus whose depth is indicated by the
amount of deflection of the transverse striae.

Locality and Horizon. — According to Hall this specimen is
from the middle portion of the Trenton at Middleville, New York.
The specimen is numbered 802 A in the American Museum of
Natural History in New York city.

Remarks. — The Trenton species here described differs from
typical Orthoceras laqueatum from the Beekmantown in its
much smaller apical angle. It is probable that if more were
known of the surface markings and internal structure of both
forms that other differences would be noted.

A similar specimen, from the Leray member of the Lowville
at Banquette Rapids in Ontario, has 3 camerae in a length

276

AUG. F. FOERSTE

equal to the diameter of the conch, where the latter is 10 mm.
At this point the diameter of the siphuncle* is 1 mm., and its
distance from the dorsal side of the conch is 3.7 mm. The
form of the siphuncle is tubular, not enlarging within the camerae.
The conch is slightly curved lengthwise, with the dorsal side
concave. There are about 40 vertical striae, more or less alter-
nating in size.

Vertically ribbed Orthoceroids of the Orthoceras laqueatum
type occur also in the Bala beds of Great Britain, where they are
known as Orthoceras Uneatum Hisinger. Orthoceras striatum
Marcklin, Orthoceras suhcostatum Portlock, and Orthoceras striato-
punctatum M’Coy are other terms whose exact value will be
understood only after the types have been fully illustrated and
described.

12. Kionoceras Sp.

Plate XXXV, fig. 2

Orthoceras laqueatum ? var. a Hall, Pal. New York, 1, 1847,
p. 206, pi. 56, fig. 3.

Specimen 22 mm. long, 7 mm. wide at the base of the specimen
and 8 mm. wide at its top, with an apical angle of about 3.5
degrees in a lateral direction. Cross-section elliptical, the dia-
meters at the base being 7 and 4.5 mm. respectively. There is
no trace of septa or siphuncle; the specimen therefore may
consist of most of a living chamber. The surface of the specimen
is marked by 20 vertical ribs, each about a quarter of a milli-
meter in width, the intervening grooves being three-quarters of
a millimeter wide. The crest of the ribs is angular, and the
elevation of the ribs is conspicuous, considering the small size
of the specimen. The crests of the ribs are crossed by trans-
verse striae, about 13 in a length of 5 mm., but no trace of these
striae is noticed in the broad intermediate grooves. Possibly
the striation is structural and within the substance of the shell
rather than on its surface.

Locality and Horizon. — From the lower shaly strata of the
Trenton at Middleville, New York. The matrix of the speci-
men contains a brachial valve of Triplecia nucleus (Hall). The

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 277

specimen is numbered 802 B in the American Museum of Nat-
ural History in New York city.

Remarks. — The general aspect of the shell with its promi-
nent ribs and broad intermediate grooves is so similar to that of
Kionoceras that the generic reference may be assumed to be
correct. Compared with Kionoceras kentlandense Kindle and
Breger, from the Black River of northwestern Indiana, the
number of vertical ribs is only 2 or 3 less, their number in the
Indiana species being 22 or 23. It is probable that the New
York Trenton species is distinct from the Indiana Black River
form, but in case of the former the interior structure is unknown
and in case of the latter the surface features are not preserved.

A specimen similar to the New York species in the number
and prominence of its vertical ribs occurs in the Leray member
of the Lowville at Pauquette Rapids, in Ontario. There are
22 ribs, and the cross-section is cylindrical. It is 21 mm. long,
and enlarges from 3.6 mm. to 4.7 mm. in this length. The
siphuncle is half a millimeter in diameter, and its position is
almost central .

13. Kionoceras kentlandense (Kindle and Breger)

Orthoceras (Kionoceras) kentlandensis Kindle and Breger,
28th Ann. Rep. Dep. Geol. Nat. Res. Indiana, 1904, p. 470,
pi. 21, fig. 2.

Type. — The specimen enlarges from 7 mm. at the lower end
to 11 mm. at the upper end, the interval being 78 mm., sug-
gesting an apical angle of 3 degrees. Only the cast of the
interior of the conch is at hand. This is marked by 22 or 23
vertical ribs which are distinct, though low, along the entire
length of the specimen, including the living chamber. At the
top of the phragmacone there is a series of 6 camerae successively
shorter in length, indicating that the specimen had attained
maturity; all 6 of these camerae occupy a total length equal to
only ten-ninths of the diameter of the conch. Of the living
chamber a length of 17 mm. remains, but this does not include
the upper part of the living chamber which, in this genus, should

278

AUG. F. FOERSTE

show a contraction along the upper part of the cast of the inter-
ior, a short distance below the aperture. The siphuncle is about
1.25 mm. in diameter at the base of the specimen and its loca-
tion is somewhat excentric. No trace of the surface markings,
beyond the presence of vertical ribs, is present in this type.

Locality and Horizon. — The type is numbered 685 in the
State Museum of Indiana, at Indianapolis, Indiana. It occurs
in a very fine-grained, brownish-gray limestone having a con-
choidal fracture, resembling some phases of the Plattin limestone
of eastern Missouri. The same limestone, at Kentland, Indiana,
contains Columnaria halli, Rafinesquina minnesotensis , Stro-
phomena trentonensis , Zygospira recurvirostris, Ctenodonta nasutay
Actinoceras heloitense, Isotelus cf, platycephalus, and Thaleops
ovatus. This is a typical representative of that fauna in the
upper Mississippi Valley which is correlated with the Black
River limestone of New York.

14. Leurorthoceras hanseni Gen. et Sp. nov.

Plate XXX y figs, M, IB; pi XXXI y fig: 1; pi XXXII y fig, 8;

pi XXXIV y fig, 2

Specimen consisting ‘ of part of a phragmacone having an
apical angle of 14 degrees in a lateral direction and of 4 or 5
degrees in a dorso-ventral direction. The cross-section of the
conch is sub triangular. This subtriangular outline is produced
chiefly by the strong and broad flattening of the ventral side of
the conch and the strong transverse curvature of the shell along
its ventro-lateral angles. Along the dorsal half of the conch
the transverse curvature is fairly regularly convex, that of the
smaller end of the specimen corresponding fairly well to the
curvature of a circle 45 mm. in diameter. The dorso-ventral
diameter at this smaller end equals 30 mm.

In a length equal to the lateral diameter of the conch there
are 6.5 camerae. Along the dorsal half of the conch the sutures
are directly transverse, but along the ventral half they curve
distinctly downward. At the upper end of the specimen the
amount of this downward curvature equals 5 mm. Along the

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 279

median part of the shell the curvature of the sutures is evenly
concave, but toward the lateral sides they tend to diverge at
angles of 155 to 158 degrees. The curvature of these sutures
corresponds approximately to that which would result if a nor-
mal cylindrico-conical Orthoceroid had one side ground away
until a similar subtriangular cross-section were produced. The
sutures curve downward a distance of 6 or 7 mm., reaching their
lowest level about 7 mm. dorsad of the center of the siphuncle.
At the lower end of the specimen where the dorso-ventral dia-
meter of the conch is 30 mm., the narrowest part of the septal
necks is slightly less than 5 mm. in diameter. The length of
these septal necks is 2 mm. and at their lower margins they curve
distinctly outward. Within the camerae the segments of the
siphuncle attain a maximum diameter of 9.5 mm. In vertical
sections the outlines of these segments tend to be circular rather
than broadly nummulitic, at least along the lower part of the
specimen. The shell material of the siphuncle appears to have
been extremely thin, and only parts of the connecting rings are
distinctly preserved, in some camerae more than in others.

No indication of surface markings is retained by the specimen,
which is a cast of the interior of the conch.

Locality and Horizon. — From some unknown locality either
on Boothia Felix or on King William Land; probably from Black
River limestone. In the Palaeontologisk Museum, Kristiania,
Norway. Collected in 1903-04 by Lieut. Godfred Hansen in
whose honor this species is named.

Remarks. — Leurorthoceras hanseni is very similar to Leurortho-
ceras chidleyense, described in this paper, from which it differs in
having a smaller apical angle; it is less strongly flattened ven-
trally, and the segments of the siphuncle are relatively narrower.
Both species are congeneric and both are regarded as belonging
to a new genus for which the term Leurorthoceras is proposed,
with Leurorthoceras hanseni as the genotype. This is charac-
terized by the flattening of the ventral side of the conch, the
broad ventral lobes of the sutures, and the relatively moderate
inflation of the segments of the camerae compared with strongly
nummulitic forms like Actinoceras,

280

AUG. F. FOEKSTE

Unfortunately the age of neither Leiirorthoceras hanseni nor
of Leurorthoceras childleyense is fully established. In both cases
the type specimens occur associated with other specimens of
undoubted Black River ^ge, but in each case the Leurorthoceras
in question consists of a matrix differing lithologically from that
of the associated Black River fossils sufficiently to admit of the
possibility of the former belonging to a different geological
horizon.

Orthoceroids with flattened ventral sides are known also from
other localities and horizons but are not known to have the same
structural characteristics of the siphuncle as in Leurorthoceras.

In Orthoceras capitolinum Safford, from the Bigby member of
the Trenton at Nashville, Tennessee, according to the figures
presented by Safford, the lateral angles of this species are even
more angular than those of Leurorthoceras hanseni. About 15.5
camerae occupy a length equal to the lateral diameter of the
conch at the top of the series of camerae being counted. At
the base of the specimen the lateral diameter is 62 mm., the dorso-
ventral one is 38 mm., the diameter of the siphuncle at its pas-
sage through the septum is 15 mm., and the distance of this
siphuncle from the ventral wall of the conch is about half a
millimeter. It is difficult to conceive how there could be room
here for a strongly nummuloidal siphuncle. I am informed by
Prof. L. C. Glenn that the type of Orthoceras capitolinum
can not be found in the Safford collection at Nashville, Tennessee,
and probably has been lost.

Specimens in the U. S. National Museum, identified as Actino-
ceras capitolinum, have undoubted nummulitic siphuncles, 15
to 20 mm. in diameter, in direct contact with the ventral wall
of the conch, but not enough of the circumference of the conch
is preserved to show the subtriangular cross-section.

In Orthoceras murrayi Billings, from the Black River limestone
on St. Joseph Island, Lake Huron, the cross-section is more
triangular than in any of the species discussed so far. This
triangularity is due not only to the flattening of the ventral side
of the conch but also to the flattening of the two dorso-ventral
sides, producing a distinct line of angularity along the median

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 281

part of the dorsal side. Where the lateral diameter of the conch
is 40 mm., the dorso-ventral diameter is 30 mm., the passage of
the siphuncle through the septa scarcely equals 6 mm., and
the distance of this siphuncle from the ventral wall is 2.5 mm.
In form, the siphuncle is tubular, not enlarging between the
septa. This is at variance with the structure of either Leuror-
thoceras or of Orthoceras capitoUnum. Along the median part
of the dorsal side the sutures curve distinctly upward.

In Tripleuroceras rohsoni Whiteaves, from Stonewall, Mani-
toba, and regarded by Whiteaves as Niagaran, the ventral side
again is flattened, and the sutures of the septa curve downward
here as in Leur orthoceras. Moreover, Whiteaves states that in
the. Manitoba species the sutures are ‘^nearly straight where they
pass over the sides. ’’ If the term straight here is equivalent to
horizontal then the general' appearance of the sutures in this
species should be similar to that in Leur orthoceras also dorsally.
In regard to the siphuncle of the Manitoba species, however,
Whiteaves states that ^Tt would have been better to say, that
its exact shape, size and relative position are not at all clearly
shown in the few specimens yet collected, though it seems to have
been marginal and enlarged between the septa. Judging
from one of the figures accompanying Whiteaves’s description
of the Manitoba species, the siphuncle of the latter must have'
been large and different in character from Leur orthoceras.

In typical Tripleuroceras, founded by Hyatt on Orthoceras
archiaci Barrande, from the Silurian of Bohemia, the cross-
section of the conch is very similar to that of Leur orthoceras
but the siphuncle is almost in contact with the ventral wall of
the conch, its segments are distinctly nummuloidal, and the
interior of the siphuncle is filled by vertical radiating plate-
like deposits. Whether Tripleuroceras rohsoni has the same
type of structure remains to be determined.

In the Silurian genus Mixosiphonoceras, founded by Hyatt on
Cyrtoceras desolatum Barrande, from the Silurian of Bohemia,
the cross-section of the conch is triangular, but the siphuncle
is situated not close to a flattened ventral side but near the
unpaired angle of the triangle. Without a knowledge of the

282

AUG. F. FOERSTE

location of the hyponomic sinus in this species it is impossible to
determine with confidence whether this unpaired angle represents
the ventral or the dorsal side of the conch, but in either event
the siphuncle of Mixosiphonoceras at least appears to occupy a
position directly opposite to that in the species previously dis-
cussed. Moreover, in Mixosiphonoceras the conch is curved
lengthwise, the siphuncle being located near the concavely
curved side; the segments of the siphuncle enlarge only mod-
erately within the camerae, and the interior of the latter is
occupied by vertical radiating plate-like deposits.

In the Devonian genus Jovellania, founded by Bayle on Ortho-
ceras huchi de Verneuil, from Nehon (Manche), France, the conch
is annulated and its cross-section is only slightly triangular,
due to a slight flattening of the ventro-lateral sides of the conch,
causing the median part of the ventral side to be slightly angu-
lated. There is no corresponding flattening of the opposite or
dorsal side of the conch. The siphuncle is located near the angu-
lated median part of the ventral side. Where the dorso-ventral
diameter is 25 mm. the center of the siphuncle is 6 mm. from the
ventral angle. The segments of the siphuncle enlarge only
moderately within the camerae and the interior of the latter is
occupied by vertical radiating plate-like deposits.

Compared with typical Jovellania, Orthoceras murrayi is not
annulated; the siphuncle is located near the strongly flattened
ventral side of the conch; the form* of this siphuncle is tubular
instead of moniliform, and the interior of this siphuncle is not
filled with. radiating vertical plate-like deposits.

15. Leurorthoceras chidleyense Sp. nov.

Plate XXXIV, figs, 1 A, B, C, D

Lateral apical angle 11 degrees. Ventral side gently convex
or distinctly flattened along its median part; dorsal side much
more strongly convex. At the lower end of the specimen, where
its lateral diameter is 39 mm., the radius of transverse curvature
of the ventral side is 20 mm., that of the dorsal side being 28
mm. At the top of the specimen, where its lateral diameter is

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 283

52 mm., the radius of transverse curvature of the ventral side
is 50 mm., that of the dorsal side being estimated at 25 mm.
At this larger end of the specimen the transverse curvature at
the ventro-lateral angles has a radius of about 11 or 12 mm.

Five earner ae occupy a length equal to the lateral diameter of
the conch at the top of the series being counted. On the dorsal
side, the sutures of the septa are directly transverse. On the
ventral side these sutures curve downward, producing broad
shallow lobes having a depth of 4 mm. at the base of the speci-
men, increasing to 5 mm. at its top. The lateral curvature of
these ventral lobes increases from 30 mm. at the base of the speci-
men to 33 mm. at its top. The septum at the base of the speci-
men slopes downward from the dorsal side toward the ventral
side at an angle of about 82 degrees with the vertical outline of
the ventral side. In fact, the structure of the phragmacone is
similar to that of an ordinary species of Orthoceras in which one
side had been filed away so as to produce a similar flattened
outline.

At its passage through the septum the siphuncle has a diameter
of about 3 mm. The center of the siphuncle is slightly less
than one-fourth of the dorso-ventral diameter of the conch
from its ventral wall. The septal necks of the siphuncle are
2 mm. in length and curve outward toward their lower margin.
The connecting rings, which join successive septal necks, are
preserved only on the ventral side of the siphuncle, but originally
these rings appear to have enlarged to a diameter of about 6
mm. within the camerae, producing segments of the siphuncle
with vertically elliptical outlines as in Loxoceras,

No indications of surface markings are present, the specimen
being a cast of the interior of the conch.

Locality and Horizon. — From blocks found loose at Port
Burwell, twenty miles west of Cape Chidley, at the northern
end of Labrador. Regarded as of Black River age on account
of associated fossils, also loose. Collected by A. P. Low. Num-
bered 7923 in the collections of the Geological Survey of Canada.

284

AUG. F. FOERSTE

16. Actinoceras tenuifilum (Hall.)

Plate XXVIII, fig, 2; Plate XXXII, fig, 1

Ormoceras tenuifilum Hall, Pal. New York, 1, 1847, p. 55,
pi. 15, figs. 1, la-c] pi. 16, figs. 1, 1 a-e; pi. 17, figs: 1, la, b.

Type specimen.- — The specimen represented by fig. 1 on plate
15 of the publication cited above is regarded as the type of the
species. Its apical angle is 12 degrees. According to figure la
on plate 16, 6 camerae occupy a length equal to the diameter
of the conch at the top of the series being counted, at the smaller
end of this type. The siphuncle is large. According to figure
la on plate 15, it is submarginal in position. In reply to an
inquiry regarding the vertical striae illustrated by Hall in figure
1 and again in figure lb on plate 15, Dr. Ruedemann states in a
letter :

The surface marking on specimen figure 1 is microscopic, but very
sharp and distinct. There are about 7-10 unequal striae to 1 mm.
Your assumption that they belong to an interior coat is probably
right, for there is a smooth patch over them at the upper end of the
conch. Besides these longitudinal lines there is in one place also a
system of fine transversal lines. The latter probably belong to the
surface and have been projected upon the lower layer when the outer
layer was dissolved.

Cotypes. — In the specimen represented by figure Ic on plate
15, the apical angle is 11 or 12 degrees. Along the smaller part
of the specimen 6.5 camerae occupy a length equal to the diame-
ter of the conch, increasing to 7 camerae toward the larger end.
About 90 mm. above the smaller end, the diameter of the speci-
men is 46 mm., that of the siphuncle is 24 mm., and the latter
is about 2 mm. from the ventral wall of the conch. The surface
of the shell is smooth.

In specimen lb on plate 16, the margin of the siphuncle is
within 1 or 2 mm. of the ventral wall of the conch; 6 or 7 camerae
occupy a length equal to the diameter of the conch. In speci-
men Ic on the same plate the siphuncle again is submarginal,
and the surface of the shell is smooth. The present location of

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 285

specimen Id is unknown. In specimen le the siphuncle is
submarginal in position; 5 camerae occupy a length equal to the
diameter of the conch at the smaller end of the specimen, increas-
ing to 5.5 camerae at the larger end; the surface of the shell is
smooth.

In specimen 1 on plate 17, the siphuncle is between 1 and 2
mm. from the ventral wall of the conch; the surface of the shell
appears to have been smooth; and, judging from the curvature
of the small part preserved, the dorso-ventral diameter was
distinctly shorter than the lateral one. In specimen lb, the
siphuncle again is submarginal in- position. In specimen 2,
the type of the variety distans, 4 camerae occur in a length equal
to the diameter of the conch at the lower end of the specimen,
increasing to 5 camerae in the second fifth of the length of the
specimen above its base, to 5.5 camerae near mid-length, and
to 6 camerae near its top; the siphuncle is within 1 or 2 mm.
from the ventral wall of the conch.

Specimens 2a and 2b on plate 58 were originally figured among
Trenton species, although doubt was cast upon their occurrence
in the Trenton. The matrix resembles that of typical Black
River specimens from the Watertown area. Dr. Ruedemann
states in a letter:

I do not remember ever having seen an Actinoceras tenuifilum in the
Trenton. It is quite common both in the Watertown and Leray lime-
stones. Some specimens have been noticed in the Lowville (see Bull.
145, New York State Mus., p. 841 footnote); Dr. Ulrich claimed at the
time that these should be a different species, but none were collected.

In specimen 2a mentioned above, the location of the siphuncle
is submarginal, and the surface of the conch, as far as known,
is smooth. In specimen 2b, the apical angle is 12 degrees. At
the lower end of the specimen the diameter of the conch is 30
mm. and that of the siphuncle is 19 mm.; at the upper end,
the diameter of the conch is about 51 mm. laterally, that of the
siphuncle being 26 mm.; judging from the curvature of the part
preserved, the shell was slightly depressed dorso-ventrally. At
the bottom of the specimen 6 camerae occupy a length equal to

286

AUG. F. FOERSTE

the diameter of the conch, increasing to 7 camerae toward the
larger end of the specimen. The surface of the shell is chiefly
smooth, but 2 or 3 mm. below the sutures of the septa there is
in several places a transverse ridge curving downward with the
sutures on the ventral side of the conch, so as to suggest the
former presence of a hyponomic sinus. The amount of this
downward curvature is at least 5 mm. near the larger end of the
specimen. It is approximately commensurate to that of the
Actinoceras from the Boothia Felix-King William Land area,
represented in this paper by figure 2 on Plate XXX.

Figured specimen. — Figure 2 on Plate XXVIII of this paper
represents a typical specimen of Actinoceras tenuifilum from the
Black River at Watertown, New York. It is part of the dupli-
cate material originally belonging to the New York State Museum
of Natural History, and was presented to the writer by Dr.
Rudolf Ruedemann. About 5 camerae occupy a length equal
to the diameter of the conch at the smaller end of the specimen,
increasing to 5.5 camerae at its upper end. The diameter of the
siphuncle equals about 64 per cent of that of the conch, and its
margin is within 1 mm. of the ventral wall of the latter. The
septa are strongly concave. The septal necks descend slightly
over 2 mm. below the general concave curvature of the septa,
and the distance between successive annulations of the siphuncle
equals or slightly exceeds 2 mm. The septa are in contact with
the lower surface of these annulations. Toward the larger end
of the specimen, the annulations of the siphuncle decrease in
size as in Par actinoceras. The sutures curve downward toward
the median part of the ventral side a distance of 4 or 5 mm.
At the base of the siphuncle, its axial part, for a diameter of
about 2 mm., is free from organic deposits, being filled with
black matrix. Toward the top of the siphuncle this axial part
free of organic deposits increases more or less irregularly to 5
mm. in diameter, indicating progressive deposition of organic
material with increasing age.

Resume. — In typical Actinoceras tenuifilum the conch is slight
' depressed dorso-ventrally, the apical angle is about 12 degrees;
the number of camerae in a length equal to the diameter of the

AKCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 287

conch usually varies between 5.5 and 6.5, but may be as low as
4 and as high as 7. The siphuncle is relatively large, equalling
at least 55 to 60 per cent of the diameter of the conch at the
lower end of the latter, though apparently diminishing in size
toward its upper end as in Paractinoceras, The sutures of the
septa curve moderately downward on the ventral side of the
conch. The surface of the shell usually is smooth, but occasion-
ally is striated or ribbed transversely in a direction more or less
parallel to the sutures of the septa.

17. Actinoceras Sp.

Plate XXX, figs. 2A, B; Plate XXXII, fig. 7

The specimen consists of a fragment of a phragmacone 130
mm. in length, of which the lower part, beneath an oblique crack,
is not figured. The specimen is strongly flattened on its dorsal
and ventral sides, probably due to compression of the enclosing
sediments previous to solidification. In my opinion this com-
pression of the sediments resulted merely in a shortening of
their vertical dimensions, and was not accompanied by any
horizontal expansion, either of the sediments or of their contents.
If this view be correct, then the present lateral apical angle of
the specimen and its present width correspond closely to the
original lateral dimensions of the specimen, though its dorso-
ventral dimensions are greatly shortened.

In its present condition the lateral apical angle of the conch
equals 10 degrees, and from 6 to 6.5 camerae occupy a length
equal to the lateral diameter of the conch at the top of the series
of camerae being counted. Along the dorsal side of the conch
the sutures of the septa curve only slightly downward, possibly
only I or 2 mm., and even this slight downward curvature may
be due to compression. Along the ventral side, on the contrary,
the downward curvature of the sutures is much more pronounced,
equalling 7 mm. Most of this downward curvature appears to
take place along the ventro-lateral parts of the conch, the down-
ward curvature being much more moderate along the median
parts of the ventral side of the conch. At the top of the speci-

288

AUG. F. FOERSTE

men the lateral diameter of the siphuncle appears to be 30 mm.
Below the oblique crack at the base of the figured part of the
specimen there is an unfigured part showing distinctly the dorsal
outlines of 3 segments of the siphuncle. As far as can be deter-
mined, the width of the siphuncle here is 32 mm. where the
lateral diameter of the conch is 48 mm. Unfortunately it is
impossible to determine with certainty whether the location of
the siphuncle is central or marginal, although I am inclined to
regard it as submarginal, extending to within 1 mm. of the ven-
tral wall of the conch, and with its nummuloidal segments oblique
to the vertical axis. The vertical outline of the segments of
the siphuncle, the distance between consecutive annulations of
the siphuncle, the length and curvature of the septal necks,
the adnation of the septa to the lower side of the annulations,
all are similar to those of Actinoceras tenuifilum.

The surface of the shell is marked by low and rather broad
transverse striae which tend to be sub-parallel to the sutures of
the septa, especially along the broad median parts of the ventral
side of the conch; but ventro-laterally, where the sutures slope
more rapidly downward, the course of the transverse striae is
slightly less oblique than that of the sutures. At or immediately
above the sutures one of the striations tends to be slightly more
conspicuous.

Locality and Horizon. — From some unknown locality, pro-
bably of Black River age, either on Boothia Felix or on King
William Land. In the Palaeontologisk Museum, Kristiania,
Norway. Collected by Lieut. Godfred Hansen in 1903-04.

Remarks. — The downward 'curvature of the sutures of the
septa on the ventral side of this specimen probably is shared
with all species in which the siphuncle is marginal or submarginal,
though the degree and angularity of this downward deflection
may vary in different species. It is regarded as. related more
nearly to Actinoceras tenuifilum than to any other described
species, but a better knowledge of the siphuncle is needed in
order to determine its relationship with some degree of confi-
dence. It may be a new species but in the absence of definite
knowledge of its siphuncle it can not serve as a type.

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS

289

18. Actinoceras amundseni Sp. nov.

Plate XXIX, figs, lA, IB; Plate XXXII, fig, 3

Specimen exposing the ventral side of the cast of the interior
of the phragmacone, including the sutures of the septa, and
exhibiting also the dorsal side of the siphuncle.

The diameter of the conch, as far as can be determined from
the transverse curvature of its ventral side, is estimated
at 70 mm. Apparently there is a slight tendency toward angu-
larity along the median part of this ventral side. It is estimated
that 6 camerae occupy a length equal to the diameter of the
conch. The sutures curve strongly downward on its ventral
side, forming an angular ventral lobe or hyponomic sinus with
sides diverging at an angle of 140 degrees. The septa are deeply
concave.

The siphuncle is almost in contact with the ventral wall of
the conch, being 1 or 2 mm. distant from the latter. The maxi-
mum diameter of the segments of the siphuncle is 28 mm.,
narrowing to 19 mm. at the grooves separating the segments.
Where the height of the segments is 13 mm., the septa are adnate
to the lower part of these segments for a height of 5 mm. ; along
this part of the segments the vertical outline of the latter is nearly
straight or only faintly concave. Above the point of departure
of the septa, the vertical outline of the segments is strongly
convex, reaching its maximum 7 or 8 mm. above the base of the
segments. The upper surface of the segments forms an angle
of 105 or 110 degrees with the vertical axis of the conch, rising
toward its ventral side. No trace of surface markings remains.

Locality and Horizon. — From some unknown locality, pro-
bably of Black River age, either on Boothia Felix or on Prince
William Land. In the Palaeontologisk Museum, Kristiania.
Collected in 1903-04 by Lieut. Godfred Hansen, on the expedi-
tion of the Gjoa, led by Captain Roald Amundsen, in whose
honor this species is named.

Remarks. — In Actinoceras amundseni slightly more than 2
segments of the siphuncle occur in a length equal to the maxi-
mum diameter of these segments. This is true also of Huronia

290

AUG. F. FOEESTE

ohliqua Stokes; in the type of Huronia septata Parks this number
is exactly 2. The chief difference between Huronia septata and
Huronia ohliqua noted so far consists in the distinct obliquity
of the upper surface of the segments of the siphuncle in the latter
and in the almost directly transverse slope of this surface in the
former species; thus indicating that the siphuncle of Huronia
ohliqua is strongly excentric in position while that of Huronia
septata is nearly central. In this respect Actinoceras amundseni
resembles Huronia ohliqua more closely. However, in Actino-
cerds amundseni the tendency toward a concave lateral outline
along the lower half of 'the segments of the siphuncle is much
less conspicuous, and this difference is regarded as sufficient to
indicate a new species. The rather angular downward deflection
of the sutures of the septa along the median line of the ventral
side of the conch may be another distinctive feature, although
it is shared with Actinoceras imhricatum Hisinger, and I suspect
that it is present also in other species in which the siphuncle is
virtually in contact with the ventral wall of the conch.

To me the general aspect of Actinoceras amundseni and of
Huronia septata is Silurian rather than Ordovician, but lithologi-
cally the type of Actinoceras amundseni resembles other speci-
mens from the Boothia Felix-King William Land area regarded
as of Black River age, and the type of Huronia septata was
obtained at the Lower Rapids of the Shamattawa River, where
the general assemblage of fossils is Ordovician.

The type of the genus Huronia is Huronia higshyi Stokes.
In this species the segments of the siphuncle resemble short
inverted pestles, the lower two-thirds of each segment being
nearly cylindrical, the upper third enlarging more or less ab-
ruptly. Huronia vertehralis Stokes and Huronia minuens Bar-
rande have the same types of structure. In Huronia ohliqua
Stokes, Huronia turhinata Stokes, and Huronia distincta Barrande
the lower part of the segments of the siphuncle is turbinate
rather than cylindrical. The figure of Huronia portlocki Stokes
resembles that of an Actinoceras in which the septa are adnate
to the lower face of the annular segments of the siphuncle.
Orthoceras persiphonatum Billings also appears to be an Actino-

AKCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS

291

ceras. An examination of the types will be necessary to deter-
mine the relationship of these so-called Huroniae.

In typical Huronia, the septa are adnate to the lower part
of the successive segments of the siphuncle, from the base of
the cylindrical part of each segment up to the outer margin of
the lower face of the annular enlargement at its top. Huronia^
therefore, differs from Actinoceras only in the cylindrical elonga-
tion of that part of each segment of the siphuncle which lies
beneath the annulation.

19. Actinoceras Sp.

Plate XXVII, fig, 7; Plate XXXII, fig. 2

Actinoceras sp. Holtedahl. On Some Ordovician Fossils from
Boothia Felix and King William Land collected during the
Expedition of the Gjoa. Videnskapsselskapets Skrifter, I, Mat-
naturv. Klasse, 1912, No. 9, pi. Ill, fig. 2.

Figured specimen. — The specimen consists of the ventral side
of a phragmacone. Owing to weathering, the siphuncle and
the adjacent parts of the septa are exposed. Near the base of
the specimen the segments of the siphuncle have a maximum
diameter of 20 mm.; the same diameter is shown 100 mm.
farther up, at the top of the specimen. The diameter of the
conch at the upper end of the specimen is estimated at 60 to
65 mm. If this be correct then the diameter of the siphuncle
is about one-third of tliat of the conch. The apical angle of
the specimen is supposed to have been relatively small, possibly
5 degrees, but the evidence for such an apical angle is not satis-
factory. The location of the siphuncle is strongly excentric.
This is indicated by the slope of its segments, the latter forming
an angle of about 60 degrees with the vertical axis of the siphun-
cle. In fact, the siphuncle probably was almost in contact with
the ventral wall of the conch.

About 9 camerae occupy a length equal to the estimated
diameter of the conch. Nothing is known about the exact direc-
tion of the sutures of the septa, but in other species with marginal
siphuncles these sutures usually curve more or less strongly

292

AUG. F. FOERSTE

downward on the ventral side of the conch. Where the diame-
ter of the conch is 60 mm. the depth of concavity of the septa
equals at least 16 mm. The segments of the siphuncle are
strongly nummuloidal, contracting from a maximum diameter
of 19 mm. to one of 14 mm at the low^er margin of the septal
necks. The latter are short, less than 1 mm. in length, the
distance between successive segments of the siphuncle equalling
scarcely 1 mm.

The central part of the siphuncle is occupied by a thick strand
of calcareous deposits enlarging toward the top ; from this central
strand deposits radiate toward the upper part of the segments
of the siphuncle. The strand itself consists of radiating elements
2 or 3 mm. wide, transversely concave when viewed from be-
neath, sometimes weathering so as to present an appearance
slightly like that of a Cystiphyllum.

Locality and Horizon. — From some unknown locality, prob-
ably of Black River age, either on Boothia Felix or on King
William Land. In the Palaeontologisk Museum, Kristiania,
Norway. Collected by Lieut. Godfred Hansen in 1903-04.

Remarks. — In the structure of its siphuncle this species resem- .
bles Actinoceras tenuifilum from the Black River limestone at
Watertown, New York. It differs in having relatively more
numerous camerae and the size of the siphuncle appears to be
relatively much smaller. It probably is a new species but not
sufficiently well preserved to serve as a^type.

20. Actinoceras Sp.

Plate XXIX, fig. 2

The specimen consists of a vertical dorso-ventral section of
the phragmacone formed during the breakage of the rock. This
section exposes the walls of the conch, the septa, and the hollow
spaces formerly occupied by the nummuloidal segments of the
siphuncle.

The apical angle of the specimen in a dorso-ventral direction
is 9 degrees. The number of camerae in a length equal to the
dorso-ventral diameter of the conch varies from 3 at the base

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS

293

of the specimen, where the diameter of the conch is 23 mm.,
to 4 at its top where the diameter of the latter is 33 mm. The
diameter of the siphuncle at these points is 15 and 21 mm.
respectively. The siphuncle either is in actual contact with the
ventral wall of the conch or is scarcely more than 1 mm. distant-
from the latter. The inner part of the groove separating suc-
cessive nummuloidal segments of the siphuncle is so narrow and
angular that the septal necks must have been short, possibly
less than 1 mm. The septa are in contact with the lower side
of the segments of the siphuncle. The nummuloidal segments
incline at an angle of about 75 degrees with the vertical axis of
the conch.

Locality and Horizon. — From some unknown locality, prob-
ably of Black River age, either on Boothia Felix or on King
William Land. In the Palaeontologisk Museum, Kristiania,
Norway. Collected by Lieut. Godfred Hansen in 1903-04.

Remarks. — This species is characterized by its relatively
large siphuncle and the relatively small number of camerae.
In both of these respects, especially in the height of the camerae.
it differs from Actinoceras higshyi Bronn, and it probably is a
new species.

The specimen figured by Holtedahl from the Boothia Felix —
King William I^and area as Actinoceras beloitense Whitfield
(Holtedahl, pi. IV, fig. 2) differs from all other forms here figured
in its small siphuncle traversing relatively tall camerae. The
number of annulations of the siphuncle in a length equal to its
diameter is only two apparently.

21. Actinoceras tenuifilum centrale Var. nov.

Plate XXVIII, fig. 1; Plate XXXII, fig. 4

Apical angle about 10 degrees; cross-section circular. Seven
and a half camerae occupy a length equal to the diameter of the
conch at the top of the series being counted. The sutures are
almost directly transverse. The siphuncle is practically central
in position, its distance fron the ventral wall being 2 mm. less
than its distance from the dorsal wall of the conch. Its diameter

294

AUG. F. FOERSTE

equals 57 per cent of that of the conch. The curvature of the
septa if continued to the center would cause a maximum con-
cavity of 5 mm. where the diameter of the conch is 46 mm.,
and the segments of the siphuncle at this point contract from a
maximum width of 26 mm. at the annulations to scarcely 19
mm. at the inner margin of the septal necks. The septa are
adnate to the lower surface of the siphuncular annulations,
becoming free from the latter along a circle 23 mm. in diameter.
The septal necks curve downward for a distance of slightly more
than one millimeter below the general curvature of the septae.
The connecting rings that extend from the base of one septal
neck to the septum next beneath form the annulations of the
siphuncle, and in vertical sections they present strongly convex
outlines laterally, while their upper surface curves strongly in-
ward or even slightly downward on approaching the base of the
septal necks. The vertical distance between consecutive siphun-
cular annulations is from one-fifth to one-fourth of the height
of the camerae.

The surface of the conch is smooth or obscurely striated
transversely with a tendency toward a slight groove at the
sutures of the septa.

Locality and Horizon. — From Watertown, New York; occur-
ing in the Black River limestone. Specimen from duplicate
material in the New York State Museum of Natural History,
at Albany, New York; presented by Dr. Rudolf Ruedemann.

Remarks. — Actinoceras tenuifilum centrale is distinguished from
typical representatives of the species by the central position of
its siphuncle; the camerae are relatively more numerous, pro-
ducing a different outline in the segments of the siphuncle; at the
same width of the conch, these segments do not diminish in size
conspicuoulsy toward the upper part of the conch. Additional
specimens may prove this form to belong to a distinct species.

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS

295

22. Actinoceras cf. tenuifilum centrale

Plate XXVIII, fig. 4; Plate XXXII, fig. 5

Specimens cut vertically through the center of the siphuncle,
and polished to show the structure of the interior of the conch.
The opposite part of the specimen ends abruptly within the
matrix along a vertical plane passing along the most distant
margin of the siphuncle in a direction parallel to the polished
section, as though part of the specimen had weathered away
before fossilization. The apical angle of the conch is estimated
at 7 degrees. At the base of the specimen the width of the conch
is 48 mm.; 8 camerae occupy a length equal to the diameter of
the conch at the top of the series being counted. The septa are
moderately concave, the amount of concavity equalling 10 mm.
in a width of 48 mm. at the base of the specimen. At this point
the maximum diameter of the segments of the siphuncle equals
23 mm., diminishing to 17.5 mm. at thelowei: margin of the septal
necks. The siphuncle is moderately excentric in position; as
far as may be determined from the specimen at hand, its dis-
tance from the ventral wall at the base of the specimen is about
9 mm., compared with a distance of 15 mm. from the dorsal
wall. The septal necks descend about 1 mm. below the general
curvature of the septa, the intervals between successive seg-
ments of the siphuncle equalling about 1 . 5 mm.

Locality and Horizon. — From some unknown locality, prob-
ably of Black River age, either on Boothia Felix or on King
William Land. Collected in 1903-04 by Lieut. Godfred Hansen.
In the Palaeontologisk Museum, Kristiania, Norway.

Remarks. — Compared with either Actinoceras tenuifilum cen-
trale or the variety ursinum the siphuncle of the specimen here
described is relatively smaller. It is impossible to determine
whether the siphuncle actually becomes narrower toward the
top, as in Par actinoceras, or whether the appearance of narrowing
in this direction is due to the section having been cut more or
less oblique to the vertical axis. In the relative number of
camerae this specimen approaches the variety ursinum. It
probably is a distinct variety, but the specimen is inadequate
for more exact discrimination.

296

AUG. F. FOEESTE

23. Actinoceras tenuifilum ursinum Var. nov.

Plate XXVIII, fig. 3; Plate XXXII, fig. 6

Actinoceras Bigsbyi (-A. tenuifilum ?) Holtedahl, Paleozoic
Series of Bear Island, 1919, p. 131, pi. 13, fig. 5.

Apical angle 16 degrees. Siphuncle apparently nearly central,
its diameter varying from 65 per cent of that of the conch at
the base of the specimen to 57 per cent at its top. From 9 to
9.5 camerae occupy a length equal to the diameter of the conch
at the top of the series being counted. The structure of the
annular segments of the siphuncle and the degree of concavity
of the septa closely resembles that of Actinoceras tenuifilum
centrale, from the Black River limestone of Watertown, New
York. The chief differences consist in the relatively greater
number of camerae and in the greater apical angle of the conch.

Locality and Horizon. — From the western part of the Antarc-
tic Mountain area on Bear Island. In the Tetradium limestone
member of the Heclahook System, regarded as of Black River
age. Original of figure 5 on plate 13 in the publication cited
above. In the Palaeontologisk Museum, Kristiania, Norway.
Collected by Floltedahl in August, 1918.

Remarks. — The species later named Actinoceras Bigsbyi by
Bronn was first figured and described by Bigsby from the equiva-
lent of the Black River limestone on Thessalon Island in the
northwestern corner of Lake Huron. Bronn’ s first figure (Leth.
Geog., 1, 1837, p. 98, Plate I, fig. 8) is a reproduction of Bigsby’s
figure 1 on plate 25 of the Trans. Geol. Soc. London, 1, 1824,
p. 198, in which, according to Foord, the segments of the siphun-
cle are not oblique to the long axis of the siphuncle (Foord,
Catalogue of Fossil Cephalopoda, 1888, p. 170). Bronn’s
second figure, published on his plate 1', is that of a species
having oblique segments of the siphuncle, the latter being in
contact with the ventral wall of the conch. Since Bronn’s first
figure must be regarded as the type, it would be desirable to
know how closely it resembles the form here described as Actino^
ceras tenuifilum centrale. As far as can be judged from the figure
presented by Bigsby, Actinoceras bigsbyi has an apical angle of

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 297

only 8 degrees, about 6.5 camerae occupy a length equal to the
diameter of the conch, and the diameter of the siphuncle is
about half of that of the conch.

Under these conditions, Actinoceras tenuifilum is not considered
as identical with Actinoceras higshyi nor with the Bear Island
species here under consideration. How close the relationship of the
Bear Island species is to Actinoceras higshyi can not be determined
until a more exact knowledge of the type of the latter has been
obtained. Judging from the greater apical angle of the Bear
Island form, its more numerous camerae, and its relatively
wider siphuncle, there is a probability of its proving distinct
from typical Actinoceras higshyi. Its resemblance to Actino-
ceras tenuifilum centrale is greater, but even in this case differen-
ces may be noted and additional material will be required to
determine the degree of relationship.

24. Actinoceras parksi Sp. nov.

Plate XXXV, fig. 3

Actinoceras bigsbyi Parks, Trans. Royal Canadian Inst., 11,
1915, p. 23, pi. 6, fig. 7.

Type. — Specimen a fragment 140 mm. in length, consisting
of one side of the phragmacone, exposing both the outer wall
of the conch and the wall of the siphuncle. The conch enlarges
at a rate of 18 mm. in a length of 100 mm. in a lateral direction,
indicating an apical angle of 10° in that direction. The conch
apparently is depressed in a dorso-ventral direction, but the
depression appears to consist chiefly in a flattening of the median
part of the ventral side. If this flattening is not due in part to
compression during fossilization, then it must have formed a
conspicuous feature of the original complete specimen. Possibly
the dimensions at the larger end of the specimen were 68 mm.
in a lateral direction and 52 mm. in a dorso-ventral one. At
the smaller end of the specimen the corresponding dimensions
appear to have been 48 and 44 mm. The rapid increase in the
amount of flattening of the ventral side toward the upper end
of this specimen appears to be too great to be normal, thus

298

AUG. F. FOEESTE

suggesting that at least part of the flattening may be due to
compression during lossilization.

The sutures of the septa apparently incline from the dorsal
toward the ventral side of the conch at an angle of* about 75°
with the dorsal side of the conch, which suggests an angle of
about 85° with the ventral side; however, the rate of inclination
is only an estimate. The location of the siphuncle is 22 mm.
from the dorsal wall at the top of the specimen, where the lateral
diameter is 68 mm.; on the ventral side the siphuncle probably
was in contact with the ventral wall of the conch, and even may
have suffered a certain amount of flattening there. At the top
of the specimen the lateral diameter of the siphuncle is estimated
at 43 mm.; at its base it probably was 33 or 34 mm., indicating
an increase in width of 10 or 11 mm. in a length of 125 mm.,
or an apical angle of about 5 degrees. In a length equal to the
lateral diameter of the conch there are 6 camerae; in a length
equal to the lateral diameter of the siphuncle there are about
4 camerae or at least nearly that number.

At the top of the specimen, where the vertical distance between
the septa along the siphuncle is 10 mm., the short tubular necks
of the septa extend downward 4.5 mm., the connecting rings
joining successive septal necks having a vertical lengths of 5.5
mm. These connecting rings or annulations extend abruptly
outward beyond the tubular septal necks for distances of 4.5
mm. The septa practically are in contact with the lower sur-
face of the annular segments of the siphuncle for a distance of
4 mm. from the upper margin of the septal necks. Along this
part of their course they form an angle of about 60° with the
dorsal side of the siphuncle, rising 17 mm. in passing from the
upper margin of the septal necks to the dorsal wall of the conch.

Calcareous deposits fill the interior of the annulations along the
lower part of the specimen, but along the upper part of the latter
the distal part of the annulations is occupied only by the same
sort of matrix which has filtered also into the camerae, indicating
that it was unoccupied at the time of the death of the animal.
From the interiors of these annulations the calcareous deposits
extend nearly horizontally inward for 3 or 4 mm. toward the
interior of the siphuncle.

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 299

The surface of the conch apparently was smooth.

Locality and Horizon. — From the Lower Rapids on the Sha-
mattawa River, in northern Manitoba. In the Ordovician.

No. 308S, in the Royal Ontario Museum of Paleontology at
Toronto.

Remarks. — This species is characterized by the relatively long
tubular septal necks separating the relatively narrow, abruptly
projecting annulations.

25. Cyclendoceras annulatum (Hall)

Plate XXXI, fig, 8

Endoceras annulatum Hall, Pal. New York, 1, 1847, p. 207,
pi. 44, figs, la, lb. Cyclendoceras annulatum Grabau and
Shimer, N. Am. Index Fossils, 2, 1910, p. 43, fig. 1241.

Type specimen. — Phragmacone 225 mm. in length, retaining
26 camerae in a length of 22 mm.; of these the lower 5 occupy
at length of 38 mm. and the upper 5 a length of 42 mm. Since
only 16 transverse annulations occur in this length of 26 camerae
it is evident that the rhythmic enlargement of the aperture of
the shell at the annulations has no connection with the periodic
withdrawal of the lower part of the animal from contact with
the basal part of the living chamber. The specimen enlarges
from a diameter of 59 mm. at its base to 70 mm. at a point 185
mm. farther up, or at the rate of 6 mm. in a length of 100 mm.,
thus indicating an apical angle of 3.5 degrees. About 7 camerae
occur in a length equal to the diameter of the conch. The
cross-section of the conch is nearly circular.

The sutures of the septa are directly transverse or only slightly
lower on the ventral side. The concavity of the septa is about
one-fifth of the diameter of the conch. On the ventral side of the
conch the vertical sections of the septa have straight courses from
the wall of the conch to within 3 mm. of the siphuncle. On the
dorsal side the concave curvature of the septa, from the wall of the
conch, to within 3 mm. of the siphuncle, only slightly exceeds
1 mm. Beginning 3 mm. from the siphuncle, the inner parts
of the septa curve strongly downward, coming in contact with

300

AUG. F. FOERSTE

the lower part of the funnel of the septum beneath at a point
about 4 or 5 mm. below the general concave curvature of this
lower septum. The septal funnels contract slightly about 2
mm. before reaching contact with the funnels next beneath, and
continue downward to a point slightly more than half the length
of the second camera beneath the septum at which the funnel
originates. The diameter of the siphuncle is one-third of that
of the conch, and its ventral side is distant one-fifth of the
diameter of the conch from the ventral wall.

The annulations of the conch are low and broad, rising only
1 mm. above the intermediate grooves. They cross the conch
obliquely, descending from the dorsal toward the ventral side
a distance slightly exceeding the height of one camera, at an
angle of about 12 degrees with a horizontal line. The interior
of the siphuncle of the type exposes only a single endocone
having a length between 100 and 110 mm.

Locality and Horizon. — From the Trenton limestone at
Middleville, New York. Type, numbered 811, in the American
Museum of Natural History in New York city.

Remarks. — Cyclendoceras annulatum probably is confined to
the typical Trenton of New York and of the immediately adja-
cent states. Similar species occur in approximately similar
horizons in adj oining geological provinces. The species described
and figured by Whiteaves (Trans. Royal Soc. Canada, 9, 1891,
p. 77, pi. 5, figs. 1, la) from the Trenton (Black River ?) between
the second and third rapids of the Nelson River, west of Hudson
Bay, enlarges much less rapidly and has much more oblique
annulations. It is a distinct species.

In typical Cyclendoceras the annulations usually are distinctly
more prominent on the ventral than on the dorsal side of the
conch. The sutures of the septa curve slightly downward both
on the ventral and on the dorsal side. The most striking feature
usually is the strong downward curvature of the annulations
along the ventro-lateral sides of the conch, and their relatively
broad concave curvature across the ventral side. Across the
dorsal side of the conch their course may be nearly straight or,
slightly curved either in an upward or in a downward direction.

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 301

Annulated Endoceratidae, such as here are included in Cyclendo-
ceras, are very well known in northern faunas. At least a dozen
species have been studied. They occur in loose Black River
blocks west of Cape Chidley at the northern end of Labrador,
on the Nelson and Shamattawa rivers west of Hudson Bay,
in Manitoba, and along that Arctic invasion which extended
southwestward to the Black Hills of South Dakota, the Big
Horn Mountains of Wyoming, the Teton range of Idaho, and
the Canyon City area of Colorado. At least 6 species are known
from this southwestern extension of the Arctic invasion. Two
species occur in Wisconsin, and 2 occur in the Watertown area
of New York, one of which, Cyclendoceras annulatum, a Trenton
form', is the genotype.

26. Cyclendoceras or Dawsonoceras sp.

Plate XXXI, fig. 2

Endoceras (Cyclendoceras) annulatum Hall, On Some Ordovi-
cian Fossils from Boothia Felix and King William Land, collected
during the Expedition of the Gjoa. Videnskapssilkapets Skriften,
1912. PI. IV, hg. 1.

A. Specimen figured hy Holtedahl. — Diameter at lowest well
preserved annulation, 57 mm. Rate of enlargement of conch,
3 degrees or less. Compressed, partly subsequent to death,
the shorter diameter equalling about 77 per cent of the longer
one. Five camerae occur in a length equal to the longer diame-
ter of the conch, each camera being occupied by a transverse
annulation whose crest is located slightly above mid-height of
the camera. The sutures rise gently toward a point which is
slightly toward the left of the median line of the published
figure. Toward the right of this point, both sutures and annula-
tions are almost directly transverse. Toward the left, both
sutures and ^nnulations curve downward, but much more moder-
ately than in typical Cyclendoceras.

B. Specimen figured in this Bulletin {Plate XXXI, fig. 2) . — Seven
annulations occur in a length equal to the diameter of the conch.
These, annulations rise 1.5 mm. above the intervening grooves.

302

AUG. F. FOERSTE

Their crests are broadly rounded and are approximately of the
same width as the intervening grooves. The annulations rise
toward a point which is slightly toward the left of the median
line of the figure here published.

In the moderate curvature of the annulations, both specimens
resemble Dawsonoceras rather than Cyclendoceras. In addition
to the two specimens described above, a third one was sent by
Dr. Holtedahl. Two of them apparently present faint traces
of vertical ribs, but not sufficiently distinct to give confidence
to their determination as Dawsonoceras. In the absence of
any knowledge of their siphuncles, their apparent association
with Ordovician forms favors their reference to Cyclendoceras.

Locality and Horizon. — From some unknown locality on
Boothia Felix or King William Land. Collected in 1903-04
by the Gjoa expedition. Deposited in the Palaeontologisk
Museum, at Kristiania. From the Silurian, in strata equivalent
to the Niagaran or Guelph.

I

27. Eurystomites (?) boreale Foord
Plate XXXIII, figs. 9 A, C

Trochoceras boreale Foord, Catalogue of Fossil Cephalopoda
in the British Museum of Natural History, pt. II, 1891, p. 23.

Original description. — ‘^Sp. Char. Shell discoid, compressed, whorls
in contact, about three in number, all exposed. Section elliptical, the
ratio of the two diameters about as 6 : 8 ; siphuncle between the centre
and the convex side. Septa approximate; two lines apart on the sides,
where the shell has a diameter of 11 lines, increasing to 2J lines where
the diameter is IJ inches. Body-chamber and test unknown. There
are no indications of ribbing or of any ornaments upon the cast.

‘^Remarks. This is a much larger species than any of those of the
Niagara rocks of North America that come at all near to it. Trocho-
ceras Aeneas, Hall, agrees with it in the distance of the septa and
position of the siphuncle, but the section is different, and there are
marks of very distinct annulations upon the cast. Salter (Journal of
a Voyage in Baffin^s Bay and Barrow Straits in the years 1850-1851,
by Dr. P. C. Sutherland (1852), Appendix, p. ccxxii) described, amongst

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 303 '

other Arctic Silurian fossils, one which he called ‘‘Lituites — , n. sp.;’^
but this is stated to have six or seven whorls at least, and therfore it
could have no affinity with the present species. There was, therefore,
no other course but to give this form a new name.

Horizon. Silurian.

Locality. Wellington Channel, Arctic America.

“Represented in the Collection by one example, collected by Captain
Inglefield.’’

The specimen described above is numbered 96955 in the British
Museum. Dr. F. A. Bather has kindly presented me with an
excellent cast of the type, also a photograph, and a cross-section.
Both the cast and the photograph suggest that the color of the
matrix is black. The cross-section is accompanied by the
following annotations, evidently applicable to that whorl which
exposes the siphuncle: Siphuncle circular, diameter 2.2 mm.;
distance from venter, 2.8 mm.; dorso-ventral diameter of whorl,
15.7 mm.; lateral diameter 13.8 mm.

EuRYSTOMITES (?) BOREALE (FoORd). CrOSS-SeCTION OF TyPE, SHOWING LOCA-
TION OP Siphuncle. Drawn by Dr. F. A. Bather

From this cross-section it is evident that the conch is a nautil-
cone with a distinctly impressed dorsal side. Since no reference

304

AUG. F. FOEKSTE

is made to enlargement of the segments of the siphuncle within
the camerae, these segments may be regarded as cylindrical in
form. From the cast it appeared possible to secure a transverse
section of the whorl (at the point B in fig. 9A on Plate XXXIII of
this paper) which is angularly elliptical (as in fig. 9B of the plate
just cited), but the excellent cross-section presented by Dr.
Bather removes all doubt about the outline of the whorls. Later-
ally, the sutures of the septa are gently concave when viewed
from above, but nothing is known of their direction along the
ventral side of the conch.

I do not know of any Silurian nautiloid combining the charac-
teristics here noted. Among Ordovician forms the cast of the
interior of the some species of Plectoceras present a somewhat
similar appearance on lateral view. However, the Wellington
channel specimen is not known to have its sutures curving
distinctly downward, along the ventral side of the conch, as in
typical Plectoceras. • The absence of any indication of obliquely
transverse plications on the ventro-lateral sides of the specimen
is not sufficient to exclude it from Plectoceras, since casts of
the interior of some species of this genus do not show readily
recognizable undulations, even when these are quite boldly
marked on the exterior. The shell of typical Plectoceras is
so thick that the interior may be quite smooth even in the
presence of a strongly ribbed exterior.

I do not know of any Silurian species of Plectoceras. Plecto-
ceras jason and Plectoceras tyrans were described by Billings from
the Chazyan of the Mingan Islands, in northeastern Canada.
Plectoceras hondi was described by Safford from the Stones
River of central Tennessee. Plectoceras undatum described by
Conrad from the Black River at Watertown, New York. Plecto-
ceras occidentale was described by Hall from the Platteville of
Wisconsin. Plectoceras halli was described by Foord from the
Black River near Quebec, in Canada. The Wellington Channel
species described by Foord under Trochoceras horeale may not
belong to Plectoceras. Its affinities may be with Eurystomites,
in which the shell is not conspicuously cosiated. This would
place it among the Tarphyceratidae.

ARCTIC ORDOVICIAN AND SILURIAN CEPHALOPODS 305

28. Orthoceras Sp.

Plate XXXIV, fig. 3 A, B

On the Fossil Faunas from Per Schei’s Series B in South-
western Ellesmer eland, Rep. Second Norwegian Arctic Expedi-
tion, in the ^^Fram^’ 1898-1902, No. 32, 1914, p. 32.

Fragment 15 mm. long, consisting of a single camera 3.5 mm. in
length, surmounted by the lower part of a living chamber 17 mm.
in length. No trace of the aperture is present, so that the original
length of the. living chamber can not be determined. Moreover,
the single camera present is so long that the conch probably is
immature, so that the size of a mature specimen also remains
unknown. The suture of the septum inclines at an angle of about
75 degrees with the vertical axis of the conch from the dorsal
toward the ventral side of the conch. This suture is almost
straight, with a slight tendency toward horizontality along the
middle of the lateral sides. The cross-section of the conch is
transversely elliptical. The lateral diameter being 14 mm., and
the dorso-ventral one slightly over 11 mm. The ventral side
is distinctly more flattened than the dorsal one. The septum
is quite evenly concave, the depth of the concavity being 2.5
mm. At its passage through the septum the siphuncle is 2.3
mm. in diameter; its center is 6 mm. from the dorsal margin of
the septum and an equal distance from the ventral margin, but,
measured in a direction strictly transverse to the vertical axis
of the conch, it is 5 mm. from the dorsal side of the latter and
6 mm. from its ventral side, thus being slightly dorsad of the
center of the conch. A vertical section through the center of
the camera failed to reveal any trace of the siphuncle except at
its passage through the septa. The septal neck apparently
was confined to a slight downward inflection of the septum.
The surface of the shell appears to be smooth.

Locality and Horizon. — Valley south of Borgen in Goose
Fjord, in southwest corner of Ellesmer eland. From the frag-
mental limestone in the' upper part of series B of Per Schei.
Collected by Per Schei June 28, 1902, and deposited in the
Paleontological Collections of Kristiania University.

306

AUG. F. FOERSTE

Remarks. — Attached to the upper part of the specimen are
a brachial valve of Camarotoechia litchfieldensis angustata
Holtedahl and a pedicel valve of Spirifer vanuxemi prognostica
Schuchert, the only two brachiopods known so far from this
fragmental limestone horizon. Unknown species of Fistulipora
and Fenestella complete our present knowledge of the fauna from
this horizon, which is correlated by Holtedahl with the Keyser
member of the Helderbergian.

PLATE XXVII

Fig. 1. Cf. Euconia quebecensis Billings. The more apical part of the specimen
consists of a vertical section passing through the center of the umbilicus. At
the base, parts of the two lower whorls are exposed along oblique surfaces. From
Victoria Head on Bache Peninsula, Ellesmereland; in the Orthoceras limestone,
regarded as of Canadian age. In the Paleaontologisk Museum, Kristiania;
collected by Per Schei in 1899. Size 22/10.

Fig. 2. Clarkoceras holtedahli Sp. nov. A, an obliquely lateral view; a rect-
angular section has been cut out from the right half of the ventral side of the
conch; one side of this section is parallel to the dorso-ventral diameter, the
other side is at right angles to the first; the former exposes the siphuncle, and
the second shows the strong lateral concave curvature of the septa. B, a strictly
lateral view of the same specimen, with an attempt to indicate the probable
dorsal and ventral outlines of the conch. Figure 1 on Plate 33 is a cross-section
of this specimen, made at the seventh septum above its base. From Victoria
Head on Bache Peninsula, Ellesmereland; in the Orthoceras limestone, regarded
as of Canadian age. In the Palaeontologisk Museum, Kristiania; collected by
Per Schei in 1899.

Fig. 3. Ellesmeroceras scheii Gen. et Sp. Nov. A, ventral view, showing rise
of sutures toward the siphuncle; size 22/10. B, the same view, but of natural
size. C, lateral view, with siphuncle on extreme right of figure; along the left
side of figure the sutures are not preserved. Figure 3 on Plate 33 is a cross-
section of the conch taken at the top of the phragmacone, the position and size
of the siphuncle being inferred from the actual exposure of this siphuncle at the
base of the specimen. From Victoria Head, on Bache Peninsula, Ellesmereland;
in the Orthoceras limestone, regarded as of Canadian age. In the Palaeontologisk
Museum, Kristiania; collected by Per Schei in 1899.

Fig. 4. Cf. Cameroceras tenuiseptum (Hall). A, lateral view, with septa not
preserved on left side ; sutures of septa apparently form shallow lobes. B, another
view, oriented so as to show the right side of figure 4A ; the irregularities in the
course of the septa are due to irregular weathering of the surface of the specimen.
C, basal view of same specimen, showing cross-section of specimen in its present
condition, no definite knowledge regarding the siphuncle is presented. Generic
reference uncertain. From Victoria Head, on Bache Peninsula, Ellesmereland;
in the Orthoceras limestone, regarded as of Canadian age. In the Palaeontologisk
Museum; Kristania; collected by Per Schei in 1899.

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE XXVII

AUG. F. FOERSTE

ARCTIC CEPHALOPODS

Fig. 5. Protocycloceras cf. lamarcM (Billings). A natural vertical section
exposing the siphuncle, apparently with invaginating septal necks. Figures 5A
and 5B on Plate 33 represent a cross-section and a vertical section of this speci-
men, as far as can be determined from the part preserved. From Bear Island; in
the younger dolomite division of the Heclahook system, regarded as of Canadian
age. In the Palaeontologisk Museum, Kristiania; collected by Dr. Olaf Holte-
dahl in July, 1918. Original of fig. 1 on Plate XIII on HoltedahPs paper ‘‘On
the Paleozoic Series of Bear Island,’’ 1919.

Fig. 6. Deltoceras (?) sp. A section lengthwise through the siphuncle and
parallel to the dorso-ventral diameter, exposing the outline of the septa; triangu-
larly limited by two oblique sections, of which the lower one is margined by a
second septum, while the upper oblique section exposes only the ventral part of
a third septum. Figures 6A and 6B Plate 33 represent the same specimen,
the first in its present condition, the second with an attempt at restoration, the
missing parts being indicated by dotted lines. Figure 6(7 on the same plate is
a cross-section of the specimen. From Bear Island; in the younger dolomite
series of the Heclahook system, regarded as of Canadian age. In the Palaeon-
tologisk Museum, Kristiania; collected by Dr. Olaf Holtedahl in July, 1918.
Figure 2 on Plate XIII of HoltedahPs paper “On the Paleozoic Series of Bear
Island,” is a direct view of the septum at the base of the specimen, before this
specimen was sectioned.

Fig. 7. Actinoceras sp. A vertical section passing in a lateral direction through
the siphuncle ; along the lower half of the specimen the exposure is due to weather-
ing, along its upper half the weathered surface has been ground off sufficiently
to expose the outlines of the annulations of the siphuncle. Along the center
of the siphuncle is the heavy strand-like deposit characteristic of numerous
species of Actinoceras . Figure 2 on Plate 32 is an attempt at a cross-section of
this specimen, suggesting that its siphuncle was small compared with the diameter
of the conch. From some unknown locality either on Boothia Felix or on King
William Land ; probably from the Black River limestone. In the Palaeontologisk
Museum, Kristiania; collected by Lieut. Godfred Hansen in 1903-04. Original
of Fig. 2 on Plate III of HoltedahPs paper “On Some Ordovician Fossils from
Boothia Felix and King William Land,” 1912, however, since the publication of
HoltedahPs paper the matrix has been ground away from the left side of the
specimen in an attempt to get some idea of the original size of the conch.

PLATE XXVIII

Fig. 1. Actinoceras tenuifduyn centrale Var. nov. A vertical section through
the center of the siphuncle. The apparent narrowing of the siphuncle at the
top of the specimen is due to oblique weathering. The axial part of the siphuncle
is occupied by an irregular tube filled by dark matrix; this is exposed by weather-
ing at the top of the specimen and is glimpsed through the calcareous deposit
in the lower part of the specimen. There also are traces of the tubuli which
radiate from this axial part toward the annular segments of the siphuncle.
Figure 4, on Plate 32 is a cross-section of the same specimen. From the Black
River limestone at Watertown, New York. Received from Dr. Rudolf Ruede-
mann of the New York State Museum of Natural History.

Fig. 2. Actinoceras tenuifilum (Hall). A vertical section through the center
of the siphuncle, tha latter narrowing toward the top. In the upper part of
the specimen the axial part of the specimen was still comparatively open before

Bulletin Scientific Laboratories Denison University Vol.^XIX

PLATE XXVI n

ARCTIC CEPHALOPODS

the infiltration of the dark matrix. Toward the base of the specimen this tubular
part is very much contracted. Traces of the tubuli radiating from the axial
part also are present. Figure 1 on Plate 32 is a cross-section of the same specimen.
From the Black River limestone at Watertown, New York. Received from Dr,
Rudolf Ruedemann of the New York State Museum of Natural History.

Fig. 3. Actinoceras tenuifilum ursinum Var. nov. A vertical section exposing
the siphuncle but not passing through the axial part of the latter. The cross-
sections of this axial part, at the top and bottom of the specimen, show that it
is dark in color like the matrix but very irregular in outline. Traces of the
tubuli which radiate from the central axis are seen most distinctly where they
approach the annular segments of the siphuncle, but a few cross-sections of these
tubuli are visible near the axial parts of the siphuncle. Figure 6 on Plate 32
is a cross-section of this specimen. The same specimen as Figure 5 on Plate XIII
of HoltedahPs paper ‘‘On the Paleozoic Series of Bear Island,” 1919. From the
Tetradium limestone of the Heclahook system on Bear Island, regarded as of
Black River age. In the Palaeontologisk Museum at Kristiania, Norway.

Fig. 4. -Actinoceras cf. tenuifilum centrale. A vertical section passing through
the siphuncle. The latter apparently narrows toward the top. Figure 5 on
Plate 32 is a cross-section of this specimen. From dolomitic strata of Black River
age on either Boothia Felix or King William Land. In the Palaeontologisk
Museum, at Kristiania, Norway; collected by Lieut. Godfred Hansen in 1903-04.

PLATE XXIX

Fig. 1, Actinoceras amundseni Sp. nov. A, ventral side of phragmacone,
showing angular hyponomic sinus. B, opposite side of the same specimen,
showing the siphuncle; the outline of the segments of the siphuncle are presented
best by the lower part of the specimen. Figure 3 on Plate XXXII is an attempt
at a restoration of its cross-section. From dolomitic strata of Black River age
either on Boothia Felix or King William Land. In the Palaeontologisk Museum,
Kristiania, Norway, Collected by Lieut. Godfred Hansen in 1903-04.

Fig. 2. Actinoceras sp. A natural vertical section of the phragmacone, show-
ing the ventral location of the siphuncle and its relatively large size. From
dolomitic strata of Black River age on either Boothia Felix or King William
Land. In the Palaeontologisk Museum, Kristiania, Norway. Collected by Lieut.
Godfred Hansen, in 1903-04.

PLATE XXIX

Bulletin Scientific Laboratories Denison University Vol. XIX

AUG. F. FOERSTE

ARCTIC CEPHALOPODS

PLATE XXX

Fig. 1. Leurorthoceras hanseni Gen. et Sp. nov. A, ventral side; dorsal side;
the lateral side is shown by Figure 1 on Plate 31, with the ventral side facing
toward the right. Figure 8 on Plate 32 is a cross-section of this specimen,
showing the flattening of the ventral side. Either from Boothia Felix or from
King William Land; in dolomitic strata regarded as of Black River age. In the
Palaeontologisk Museum, Kristiania; collected by Lieut. Godfred Hansen in
1903-04.

Fig. 2. Actinoceras sp. A, ventral side of phragmacone; B, an oblique lateral
view, showing most of the ventral side, and exhibiting the transverse striae
along the ventro-lateral angle of the conch. Figure 7 on Plate 32 presents the
transverse outline of this specimen near its top, but the ventral outline of the
siphuncle is not known definitely. Either from Boothia Felix or from King
William Land ; in dolomitic strata regarded as of Black River age. In the Palaeon-
tologisk Museum, Kristiania; collected by Lieut. Godfred Hansen, in 1903-04.

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE XXX

AUG. F. FOERSTE

ARCTIC CEPHALOPODS

PLATE XXXI

Fig. 1. Leurorthoceras hanseni Gen, et Sp. nov. Lateral view of specimen
figured on Plate 30 (fig. 1), with the ventral side facing toward the right.

Fig. 2. Cyclendoceras or Dawsonoceras . Apparently a part of a living chamber,
with the median line of the ventral side about 10 mm. from the right margin of
the figure. Either from Boothia Felix or from King William Land; from dolo-
mitic strata regarded as of Ordovician age, but which may turn out to be
Niagaran. In HoltedahPs paper ‘‘On Some Ordovician Fossils from Boothia Felix
and King William Land,” Figure 1 on Plate IV presents another species collected
during the same expedition and undoubtedly from the same locality; in this
specimen the sutures of the septa occupy the grooves between the annulations.

Fig, 3. Cyclendoceras annulatum (Hall). All but the extreme top of the type
described and figured by Hall (Pal, New York, 1, 1847, pi. 44, figs, la, lb). The
ventral side is on the right of the figure. From Watertown, New York; in the
Trenton limestone. No. 811 in the American Museum of Natural History in
New York City.

Bulletin Scientific Laboratories Denison University Vol. XIX

PLATE XXXI

AUG, F. FOERSTE

ARCTIC CEPHALOPODS

PLATE XXXII

Fig. 1. Actinoceras tenuifilum (Hall). Cross-section of specimen, Figure 2
on Plate 28, from Watertown, New York.

Fig. 2. Actinoceras sp. Cross-section of specimen. Figure? on Plate 27, from,
either Boothia Felix or King William Land.

Fig. 3. Actinoceras amundseni Sp. nov. Cross-section of specimen. Figure 1,.
on Plate 29, from either Boothia Felix or King William Land.

Fig. 4. Actinoceras tenuifilum centrale Var. nov. Cross-section of specimen,.
Figure 1 on Plate 28, from Watertown, New York.

Fig. 5. Actinoceras cf. tenuifilum centrale var. Cross-section of specimen,.
Figure 4 on Plate 28, from either Boothia Felix or King William Land.

Fig. 6. Actinoceras tenuifilum ursinum Var. nov. Cross-section of specimen,.
Figure 3 on Plate 28, from Bear Island.

Fig. 7. Actinoceras sp. Cross-section of specimen. Figure 2 on Plate 30, from
either Boothia Felix or from King William Land.

Fig. 8. Leurorthoceras hansejii Gen. et sp. nov. Cross-section of specimen,
Figure 1 on Plate 30 and Figure 1 on Plate 31, from either Boothia Felix or from
King William Land.

In all of these figures the missing parts are indicated by broken lines. Both
the maximum and minimum dimenions of the siphuncle at the annulations and
at the intermediate grooves are indicated.

Bulletin Scientific Laboratories Denison UniversityIVol. XIX

PLATE XXXII

AUG. F. FOERSTE

ARCTIC CEPHALOPODS

PLATE XXXIII

Fig. 1. Clarkoceras holtedahli Sp. nov. Cross-section of specimen, Figure 2
on Plate 27, from Bache peninsula.

Fig. 2. Eremoceras syphax (Billings). Cross-section of specimen, Figure 8
on this plate, from Point Levis, Quebec.

Fig. 3. Ellesmeroceras scheii Gen. et Sp. nov. Cross-section of specimen,
Figure 3 on Plate 27, from Bache peninsula.

Fig. 4. Protocycloceras whitfieldi Ruedemann. Vertical section of a specimen
from Fort Cassin, Vermont.

Fig. 5. Protocycloceras cf. lamarcki (Billings). A, cross-section; B, vertical
section; both sections based on specimen. Figure 5 on Plate 27, from Bear Island,
but restored in part.

Fig. 6. Deltoceras (?) sp. A, chiefly a longitudinal section through the center
of the siphuncle, parallel to the dorso-ventral diameter. B, an attempted resto-
ration, based on the preceding. C, cross-section, showing the siphuncle. Same
specimen as Figure 6 on Plate 27. From Bear Island.

Fig. 7. Protocycloceras lamarcki (Billings). A, specimen No. 550a of the type
series, showing sutures of the septa. B, specimen No. 550b of the type series,
showing the upper surface of a septum, with part of margin of siphuncle distorted
by crushing. C, specimen No. 550c of the type series, showing sutures of the
septa only near the base of the specimen. D, vertical section through the com-
posite specimen 508 and 508a, showing the siphuncle. A, B, C, from Huntingdon
county, Quebec. D, from Romaine on the Gulf of St. Lawrence. Of Canadian
age. All specimens in the Victoria Memorial Museum, at Ottawa, Canada.

Fig. 8. Eremoceras syphax (Billings). A, ventral view, showing the large
siphuncle. B, lateral view, with siphuncle on left. C, dorsal view, with pseudo-
siphuncle made by tool-marks of the original cleaner of the specimen, formerly
misinterpreted as the siphuncle. From Point Levis, Quebec, in strata of Canadian
age. Type, numbered 819 in the Victoria Memorial Museum, at Ottawa, Canada.

Fig. 9. Eurystomites (?) boreale (Foord). A, lateral view of type specimen.

B, incorrect cross-section, secured from cast of type at point B in Figure 9A.

C, cross-section prepared from the original specimen, probably along the crack
crossing the center of the type diagonally, as in Figure 9A; part of a figure drawn
by Dr. F. A. Bather from the original specimen. From the Wellington Channel,
in Arctic America, collected by Captain Inglefield. No. 96955 in the British
Museum of Natural History, in London.

PLATE XXXI 11

Bulletin Scientific Laboratories Denison University Vol. XIX

ARCTIC CEPHALOPODS

PLATE XXXIV

Fig. 1, Leurorthoceras chidleyense Sp. nov. A, ventral side. B, lateral side.
C, cross-sections at top and bottom of specimen, showing location of siphuncle
at bottom. D, vertical section along dorso-ventral plane, showing siphuncle.
From loose blocks of Black River limestone, found at Port Burwell, 20 miles
west of Cape Chidley at the northern end of Labrador. No. 7923, Geol. Surv.,
Canada.

Fig. 2. Leiirorthoceras hanseni Gen. et Sp. nov. Vertical section along dorso-
ventral plane of same specimen as fig. 1 on pi. 30. The specimen was cut diago-
nally sufficiently to cause the siphuncle to appear narrower toward the top, though
in reality it enlarges slightly in that direction. From the Black River limestone
either on Boothia Felix or on King William Land.

Fig. 3. Orthoceras sp. A, dorso-lateral view, with ventral side on right, not
showing the maximum slant of the sutures of the septa. B, cross-section, show-
ing the slight flattening of the ventral side and the location of the siphuncle.’
From the Valley south of Borgen in Goose Fjord in southwestern Ellesmereland.
From strata comparable wdth the Keyser member of the Helderbergian. In the
Palaeontologisk Museum, Kristiania: collected by Per Schei in 1902.

r

[

PLATE XXXV

Fig. 1. Kionoceras trentonense Sp. nov. Lateral view, magnified 27 /lO. The
alternation in size of the vertical riblets is shown best by the left half of the
figure. From the original specimen represented by fig. 2 b, c, on pi. 56 of Pal.
New York, 1, 1847. From the middle Trenton at Middleville, New York.

Fig. 2. Kionoceras sp. Lateral view, magnified 27 /lO. From the original
specimen represented by fig. 3 on pi. 56 of Pal. New York, 1, 1847. From the
lower shaly strata of the Trenton at Middleville, New York.

Fig. 3, Actinoceras parksi Sp. nov. View of a natural exposure of the interior
of the siphuncle, showing on the left a polished vertical section exposing the
septa, the long septal necks, and the relatively short connecting rings. From
the Lower Rapids on the Shamattawa River, in northern Manitoba, west of
Hudson Bay, in limestone of Ordovician age. No. 308 S, in the Royal Ontario
Museum of Paleontology at Toronto.

PLATE XXXV

Bulletin Scientific Laboratories Denison University Vol. XIX

AUG. F. FOERSIE

ARCTIC CEPHALOPODS

'Jvr.. •

)

v'

<■

?

'■-S

V

. T-'-'

.T

■ '• '• >,

' ' .

iSI^

Or;.'

'#•

it’*,

^’. (f

i

■ i

■■':i

.

\

i

?:

■

I

REVOLUTION VS. EVOLUTION: THE PALEONTOLO-
GIST RENDERS HIS VERDICT

KIRTLEY F. MATHER
I

Senators and bolsheviki, capitalists and members of the
I. W. W., preachers and brick-layers, all, with few exceptions,
are sincerely honest in their desire to improve the conditions,
domestic, national and international, which determine the life
and happiness of the individuals with whom they are acquainted.
Most people would really be quite pleased, provided it did not
entail too much labor or self-sacrifice on their own part, if the
organization of society could be made more efficient and less
wasteful, more subservient to the good of all and less profitable
to the chosen few. We are still thrilled by the visions of the
prophets of old and the propagandists of today with their dreams
of a ^^new day’^ and a ^^new world.” But just about there,
our unity of mind and action ceases. Few among the real
thinkers of any class are certain as to what these better condi-
tions, which shall usher in the ‘Mawn of the new day,” shall
be. And among these few, scarcely any two are agreed between
themselves in regard to other than general and hazy ideas.
More deplorable still, there are even more sharply defined
differences of opinion among forward-looking men as to the
method by which the reforms which they desire may be accom-
plished.

At bottom, it is really this difference of opinion as to method
that distinguishes the Socialist with the Red Flag from the
Republican with the Stars and Stripes, or the priest with his
ritual from the evangelist with his sawdust trail. The distant
goals which each envisions, although by no means coincident,
at least have the merit of location in the same quarter of the
universe; but the roads which are suggested as proper avenues

307

308

KIRTLEY F. MATHER

of approach to those comparatively adjacent goals are not even
approximately parallel. The aims are similar, but the routes
are various.

In general, would-be reformers — and that of course includes
all adolescent or adult humans of sound or unsound mind — fall
readily and naturally into two classes: those who believe in
revolution, and those who believe in evolution. Each of these
classes may be further divided into two sub-classes, dependent
upon the reformer’s notion of the forces which must be relied
upon to accomplish successfully the desired result; reliance may
be placed on the one hand upon human and natural forces, on
the other upon suprahuman and supernatural.

Among those who believe in revolution, there are in the one
group our inconoclastic brethren who have faith in the ability of
the proletariat not only to overthrow the bourgeoisie but to
perfect a new and beneficent organization of human affairs,
which shall rise phoenix-like from the red flames of the blazing
ruin of things-as-they-are. And on the other hand, in the same
broad class of believers in revolution, there are those religious
zealots who confidently await a day of destruction and judgment,
when suprahuman forces shall be loosed in supernatural ways,
and in the twinkling of an eye our present failure of a world shall
be swept aside to make way for ^The new heaven and the new
earth.”

In the ranks of the evolutionists, a similar cleavage is apparent.
Some believe that the forces long operative, and even now
operating, within the world are competent eventually to win
mankind through to the high goal which seems to be set for
him; that the Administrator of the Universe — to use Dr. T. C.
Chamberlin’s apt phrase — is powerful enough to make right
forever triumphant without resorting to catastrophic destruc-
tion of the majority of his subjects. Others, impressed with the
might of the quiet but constant forces of evolution and con-
vinced of the futility of revolutionary expedients, fail to find
the hope of better things in the present trend of affairs; rampant
greed and unalloyed selfishness, eternal competition and bitter
struggle, ever recurring tragedy, these seem to be the constant

REVOLUTION VS. EVOLUTION

309

companions of the evolutionary process from which the hit-or-
miss method of Nature may never permit mankind to escape.
For the disciples of evolution, who are thus led to believe in the
impotency of natural laws and human worth, the future must
indeed be black with despair.

Then, which shall it be? Evolution or revolution? Human
ability and natural processes or suprahuman forces and super-
natural power? Obviously, the question is far from being
merely academic. One ’s whole philosophy of life, one ’s allegiance
to the myriad welfare organizations of the land, one’s alignment
on the foremost political and social questions of the day, all
these and more depend upon the answer. Nor is it a question
which can be long postponed. So insistent has the clamor of the
revolutionists become, that it penetrates even to the sequestered
laboratory of the paleontologist and bids him rise from his
study of fossil shell and petrified bone to give ear to the babel
of twentieth century voices. And not unwillingly does he join
the debate; for when it comes to a question of evolution who is
there better fitted to make response than he who has visuahzed
the stream of life which pulsed along the channels he has traced
from those far-off Cambrian days until now?

Consider the lilies of the field and the birds of the air, the
fishes of the sea and the creatures of the land. Retrace with
the student of ancient life the long road that leads to man;
watch the phantoms behind us” marching step by step along
that road. Search out the milestones of the past that mark the
successful accomplishment of the great forward movements in
life. For these creatures of the vanished ages, who have left
the story of their lives recorded in the rocks of the earth’s crust,
are our kinfolk. Their problems are ours; our problems are but
theirs. They have blazed the trail for us. The route to success
and progress and ‘‘better things,” which they found, is still
open. The paths to . failure, which they trod, are today as fair
to look upon and as fatal to pursue as they have ever been.

310

KIRTLEY F. MATHER

II

Had you asked a paleontologist of two or three generations
ago these questions which we are now propounding, the chances
are he would have replied unhesitatingly that life had progressed
in the past by virtue of a succession of violent and tragic revolu-
tions. For this was the belief and teaching of Cuvier, Lord of
France, and one of the greatest of the founders of the science of
Paleontology. Embedded in the gypsum quarried from the hill of
Montmartre, now included within the limits of the city of Paris,
Cuvier had found remarkably well preserved fossil bones of
animals which he correctly inferred had been living in that
region at the time the rock strata in which they were entombed
had been accumulated. His knowledge of living creatures
from all parts of the world was unusually extensive, and he
clearly saw that these relics of the past represented animals
quite unlike any known existing ones. They must be members
of vanished races, swept out of existence in the prime of life
by some overwhelming catastrophe such as the inundation of
the sea over a subsiding continent, but whose remains had been
fortunately preserved and were now displayed in Nature’s vast
museum. Perhaps the very floods of sea water from which the
gypsum had been precipitated had also drowned the hapless
inhabitants of the land, whose bones were buried on the sea floor.

Thus arose the doctrine of ^^catastrophism,” a doctrine
which was subsequently expanded until it enthroned the princi-
ple of revolution as the prime factor in the forward march of
life. In the minds of Cuvier’s followers, during the earlier
half of the nineteenth century, it was the general belief that the
cataclysms were world- wide, and that the slaughter of the older
assemblage of animals and plants was followed by the special
creation of a new and more improved group of creatures to
inhabit the vacant spheres of activity. D ’Orbigny, for example,
taught that ^Twenty-seven times in succession, distinct crea-
tions have come to repeople the whole earth with its plants
and animals after each of the geological disturbances which
destroyed everything in living nature.”

I

EEVOLUTION VS. EVOLUTION

311

Or, if the idea of numerous distinct creations’’ is somewhat
repugnant because it leaves open the way for the flippant sug-
gestion that the Creator was not at first an expert artisan but
required a lot of practice before he became sufficiently adept
to perform his functions properly on a certain Saturday in the
year 4004 B.C., the theory of catastrophism may be slightly
amended. Let it be supposed that the devastating cataclysm
was not quite world-wide, but that individuals here and there
escaped to become the progenitors of the new assemblage of
living creatures. This was apparently about what Cuvier
really had in mind. In times of excessively arid climate
there would somewhere be an oasis where a few favored individ-
uals would escape the parching drought. When a glacial episode
threatened to freeze the inhabitants of land and sea and spread
a mantle of Artie snow and ice over all the face of the earth,
the climatic pendulum would be reversed just in time to save a
dwindling minority to serve as seed for repopulating the ice-freed
lands. Volcanic fires and earthquake shocks ordinarily would
not completely devastate all habitated places of the earth’s crust
at any one time; somewhere a few individuals would escape to
provide descendants capable of returning to the wasted lands
when the cataclysm had ceased. Tyre and Sidon went on their
wicked way unscathed when fire from heaven rained down upon
Sodom and Gomorrha, you will recall. Or perchance, safety
from inundating sea or deluge might be found upon a high
plateau or mountain top, such for example as Mount Ararat.

Thus by comparatively easy stages we might shift from the
camp of Cuvier and d’Orbigny to another school of old masters
in the science of Paleontology, among whom Sir Charles Lyell
was foremost. Long before the time of Darwin, this group of
scientists had come to believe in evolution of one sort or
another and pinned their faith to the doctrine of ^ ^ continuity. ”
They noticed that there were certain ^Tong-lived” species of
animals and plants, whose remains were found unmodified in
formation after formation regardless of the catastrophes which
might have occurred in the intervals between their deposition.
On the coast of Wales at the present time, for instance, certain

312

KIRTLEY F. MATHER

brachiopod shells which weather out of rocks dating back to
the very oldest of fossiliferous strata are scarcely distinguishable
from the shells of living brachiopods washed ashore by the waves
which are daily exhuming the relics of antiquity from the cliffs
against which they dash into spray.

Again, these believers in the continuity of life, regardless
of local disturbances, adversities and cataclysms, called atten-
tion to the fact that the fossil remains of successive groups of
plants or animals were as a rule indicative of creatures only
slightly modified from those which had preceded them. Abrupt
and sweeping changes in the assemblage of living beings were
apparent whenever there were gaps in the record of life, but when
the missing chapters were supplied by more extensive study the
vital stream Was shown to have been flowing on its way un-
broken. Proof was not lacking that the presence of an altogether
different assemblage of fossils in two successive series of rocks
was due to the migration into that locality of creatures who had
been slowly developing elsewhere. The pulse of life might beat
a little irregularly now and then, but never had it been entirely
suspended.

Gradually this notion of continuity of life, regardless of seem-
ing interruptions in the record, gained sway, and at the present
time there are no paleontologists who entertain any other idea
of organic development. But still our question is unanswered.
Granting the unbroken flow of the stream of life, what part in
the progress of that stream has been played by the rapids and
cataracts? Have they been essential to its onward flow, or
are they only spectacular displays, actually of less importance
than the quiet reaches where the deeper waters move?

Ill

The close of the Paleozoic Era — that long interval of ancient
time during which invertebrates and fishes, with later the
addition of amphibians and reptiles, were the only animals upon
the earth — was marked by a series of adverse episodes so dis-
turbing in their influence upon plants and animals that it brought
about what is commonly called a ^T’evolution’^ in the organic

REVOLUTION VS, EVOLUTION

313

world. Episode number one in the thrilling serial was a crustal
movement which crumpled the outer layers of the earth into a
long line of mountain ranges stretching across what is now Bel-
gium, Northern France and Southern England. These, the
Paleozoic Alps’^ of Europe, have long since been worn down
and washed into the sea, but the roots of the quondam cordillera
still remain. This crustal crumpling was accompanied by a
general upward movement of all the continents and a deepening
of the ocean basins so that shallow seas which had hitherto
spread out over a large proportion of the continental platforms
retreated oceanward and left dry land or broad swamps where
great bays and estuaries had been. It so happens that the
overwhelming majority of marine organisms are adapted to life
in the shallow seas alone. The greater part of the deep sea is
nearly or quite devoid of life ; only in the upper hundred fathoms
and on the ocean floor are living creatures found. More than
95 per cent of all the inhabitants of the sea are confined to the
shallow coastal waters between the strand and the hundred-
fathom line. Previous to this crustal disturbance, the area of
this particular zone had been very large and life had expanded
and multiplied therein. Now, its area was reduced to a small
fraction of its former extent, and the severity of the struggle for
existence that must have taken place within this dwindling;
zone can well be imagined.

Then followed episode two. Gradually the climate of the
world changed from its former agreeable warmth to Arctic
cold. Great ice sheets, far more extensive than those of the
much later and better known epoch to which the name ^^The
Great Ice Age’’ is frequently applied, formed upon the lands
and spread in all directions. In India and in Bolivia these
glaciers reached even within the tropics, while in South Africa
and Australia they were only slightly less extensive. The life
of land and sea, alike, was diastrously affected by these adverse
climatic conditions, and the end of the Paleozoic Era marks
also the termination of scores of genera and families and even
of many orders of animals and plants.

314

KIRTLEY F. MATHER

Episode number three was somewhat similar to that which had

opened this chapter of earth history. Its chief event was the
building of the Appalachian Mountains, which in their youth
were mighty ranges not unlike the Rockies of British Columbia.
The areas of hospitably shallow seas were still further reduced,
and vast sandy plains stretched monotonously across the states
of Texas, Oklahoma and New Mexico. Deserts, equalling the
Sahara in magnitude and aridity, existed in parts of Europe and
North America where today are fertile farms and majestic
forests. The tribulations heaped upon the creatures of the land
became even more numerous than before, as the humid areas of
temperate climate were still further diminished in extent and
number. The physiographic and climatic changes wrought
during these three episodes in earth history could not fail to
leave their indelible imprint upon the entire population of the
globe, composed as it has always been of individuals quick to
respond to modifications in their geographic environment.

With the crumpling of the Appalachians, the mighty forces
pent within the body of the earth seem to have spent their
energy. Equilibrium of the opposing stresses was once more
attained. The close of the Paleozoic Era was followed by another
long era of comparative stability of the earth ^s crust. .Gradu-
ally the normal temperate climate of the globe was restored;
once more, broad shallow seas crept over the lower portions of
the continental platforms; again, the regions of land and sea
most hospitable to life expanded until they covered a large pro-
portion of the planet; a long era of prosperity for the earth
inhabitants was ushered in. This, the Mesozoic Era, the time
of medieval life, is referred to as the Age of Reptiles, because
during it the animals of this class aspired to the rulership of
every domain of life, the land, the sea and the air.

What were the effects of these revolutionary episodes upon
the creatures subjected to them? Were they for good or for
evil? Space forbids a full discussion of the problem; we may
concentrate our attention upon a single class of animals and
take their experiences as typical of all. And I choose from
among the many available illustrations that afforded by these

REVOLUTION VS. EVOLUTION

315

self-same reptiles whose numbers were so great during the age
which followed; for to me their story is fraught with the greatest
interest.

D’Orbigny taught that the reptiles were created immediately
following the world-wide cataclysm, into which the three
episodes enumerated above were exaggerated, as a part of the
process of re-peopling a world from which all life had been
annihilated. But the researches of Williston and others have
revealed the fact that the reptiles had been in existence long
before these staggering events, had indeed progressed far along
their varied and spectacular career before the close of Paleozoic
time. Already they had deployed into several distinct orders;
already more than one strain had risen to the climax of its
career, tasted the fruits of success in its chosen line, and passed
away, blotted out of existence in the never-ceasing competition
of rival races, or failing utterly to withstand new and adverse
conditions in their environment.

Take for example the curious fin-backed lizards,’’ known to
science as Pelycosaurs. From each vertebra of their spinal
columns a long bony spine grew vertically upward, and, the
whole series sheathed in leathery integument, formed a ^^fin”
along the middle of their backs. Successive genera are known
with increasingly high fins until the climax of this reptilian strain
was achieved in a creature whose fin was twice as high as his
back even when his body was lifted as far from the ground as
was possible for his stubby legs to elevate it. His fin spines
were more than two feet long and each was decorated by short
spicules of bone growing horizontally at right angles to the
long bony column. Just what purpose was served by these
bizarre appendages is not known; whether for decoration,
defense or other practical use, it matters not in the present dis-
cussion. The important fact is that this entire reptilian race
was swept out of existence at the close of the Paleozoic Era and
left, so far as now known, no descendants to make their contribu-
tion to the Age of Reptiles.

Again, there lived at this time one group, the Mesosaurs, who
had become entirely adapted to life in the fresh waters of rivers

316

KIRTLEY F. MATHER

and lakes. They are among the first of many creatures who
forsook the land, modified their legs into swimming apparatus
of one form or another, mimicked the fishes in the shape of their
bodies, and returned to the water which their remote ancestors
had long before deserted to invade the new terrestrial domain.
Interestingly enough, these fresh-water reptiles are known to
have lived during the closing epochs of the Paleozoic Era only
in South America and South Africa; how they travelled from
the one continent to the other, they could not exist in the salt
water of the sea, is one of the unsolved problems of the paleon-
tologist. They, tl)o, had their day and ceased to be, and their
whole life history was closed before the Age of Reptiles began.

But several of the reptilian strains were more successful or
more fortunate; they persisted, to become not only the progeni-
tors of the varied saurian masters of the Mesozoic Era but of the
higher class of birds and still higher mammals as well. Clumsy,,
crawling creatures they were, with much bone and little brain
in front of their squat shoulders. Heavy in body, short in leg^
many of them could little more than drag their trunks over
the sand or through the mud. For some of them the vast
arid tracts seemed purposely designed, and there they multiplied
in number, deployed into several different evolutionary strains
and slowly, conservatively perfected that complete adaptation
to the dry land which was necessary to the further progress of
life. Truly reptilian in habits, the cold blood which coursed
sluggishly through their veins was not shocked by the icy drafts
of the glacial climates. The disastrous episodes which closed
the Paleozoic Era left them unscathed; the rush of the stream of
life swept them forward to the high destiny which they realized
in the Age of Reptiles.

But their success was not achieved as a result of the revolu-
tionary events which mark the transition between those two
eras. They had already won for themselves their leading parts
in the drama of life. Long ages of quiet unassuming preparation
had preceded those spectacular moments. The slow and steady
progress which they were making seems simply to have
been accelerated by the very adversities of -that comparatively

REVOLUTION VS. EVOLUTION

317

short interval of upheaval. The revolution was a success only
because of the preceding preparatory development which pro-
gressed so deliberately and inconspicuously that it entirely
escaped the attention of the earlier students of ancient life,
thrilled as they were by the apparantly abrupt and sweeping
changes which the revolution wrought. Those reforms’^
were merely the climacteric fruition of a lengthy period of pre-
paratory evolution.

Examples without number, drawn from other classes of
animal and of plant life at this same milestone in the progress
of life, parallel this one. The same story recurs again and
again as other milestones are passed. We may pause for but *
one other illustration.

The transition from the Mesozoic Era to the Cenozoic Era,
the era of modern life, is marked by physiographic and climatic
changes not unlike those which characterized the transition
just sketched. Once more, the stresses slowly accumulating
within the rigid body of the earth were piled one upon another
until they could be no longer resisted; the pent-up energies must
be released as before. But the chief scenes of the drama were
staged in other places; the most conspicuous milestone is found
where the American Cordillera rears its cloud-swept peaks from
Alaska to Cape Horn. This mightiest of all but one of the
modern mountain systems dates its birth from the close of the
Age of Reptiles. The travail which brought it into existence
was marked by violent volcanic outbursts on a gigantic scale;
Vesuvius, Stromboli, Krakatoa, Pelee and Mauna Loa, all
crowded into a single county and set in simultaneous eruption
would perhaps give some idea of the events which constitute
episode one of this second serial. Again, there was a general
elevation of the continental platforms and a withdrawal of the
shallow seas to the newly deepened ocean basins. Again,
there were far-reaching climatic changes; even another glacial
episode, if, as seems probable, the glacial deposits recently
discovered in Colorado and British Columbia date from this
time. Again, there was a second mountain-making crumpling
of the earth ^s crust, this time concentrated in the same cordillera

318

KIRTLEY F. MATHER

which had come into being as a result of episode one and there-
fore much more difficult of interpretation. All in all, the changes
in the physical environment of the earth’s inhabitants were
nearly or quite as sweeping as those which resulted in the strik-
ing modifications of life as it passed from the Paleozoic to the
Mesozoic types. And, as before, the living creatures responded
to these changes so completely that another ^ devolution” is
recorded in the older text-books. In a word, the host of rep-
tiles which had dominated land and sea and sky were swept
into oblivion and their places were promptly assumed by mam-
mals, the most advanced of all creatures. As a consequence,
• the Cenozoic Era is known as the Age of Mammals.

Again, let us enquire more particularly into the history of
the group of animals which seem to have profited most by
this ^devolution. ” To state it briefly, the story of the mammals
at this time is almost an exact parallel to that of the reptiles
at the close of the Paleozoic Era. Instead of having been
created subsequent to the devastating catastrophe which was
believed to have left an uninhabited world for them to people,
we now know that they had long been in existence. The first
relics of mammalian life date far back in the Age of Reptiles.
Before its close there' were countless hordes of small warm-
blooded creatures, competing, in spite of their insignificant size
and by virtue of their superior brain power, with the gigantic
and powerful but clumsy and unintelligent reptilian masters
of the world. This very competition, carried on during at
least three geologic periods, gave them strength and cunning
not only to outwit their opponents but also to adapt themselves
even to such adverse environmental conditions as surrounded
them during the geographic revolution inaugurated by the
first birth-pains of the American Cordillera. Far more ready to
profit by its changes, because of their mobility, their warmth-
preserving pelts and their intelligence in securing new food
supplies, than were the reptiles, they succeeded where their
competitors failed. Coincident with the return of the balanced
conditions which lead to long periods of comparative stability
of the earth’s crust, the mammals promptly acceded to the

REVOLUTION VS. EVOLUTION

319

many thrones left vacant by the reptiles, unable to withstand
the adversities of climatic and physiographic change coupled with
the ever-increasing ability of their mammalian foes, and soon
dominated land and sea. Soon thereafter they even aspired to
the dominion of the air, but in that sphere of activity they have
thus far failed to rival the birds.

The conclusion seems unescapable that again the revolutionary
achievement was merely the climax of a long slow upward
climb. Had not the preparation of the mammals been complete
they could scarcely have seized so successfully upon the oppor-
tunities which opened before them at this time. The conclusion
is further fortified when we note that the immediate ancestors
of mammals, the theriodont reptiles, had been in existence
before the close of the Paleozoic Era, but, though they fore-
shadowed the mammals in many important particulars of body
structure, they apparently made no marked response to the
environmental changes occurring at the close of that era. The
long preparatory period had but begun for the mammalian
strains; not yet had they attained the abilities sufficient to
profit by those changes; that ^ devolution’’ gained them little
or nothing, simply because they were not ready to take advan-
tage of it. The inauguration of the mammals as the lords of
the earth must wait, regardless of ^devolutions,” until the off-
spring of those theriodents had by the long slow processes of
evolution completed the training prerequisite to that proud
position.

This seems to be the law of life. Revolutions are of little
avail unless preceded by long and generally agonizing periods of
preparation. Slowly progressive evolution may lead to a
spectacular climax of fruition during a moment of organic up-
heaval, but the attainment is the result of the preparatory
development, not of the revolutionary forces. Time and again,
upon the long road so painfully traversed during the geologic
eras, important milestones have been passed, great upward
steps have been achieved, unaccompanied by anything remotely
resembling a ^devolution;” but never, so far as I am aware, has
any group of animals or plants gained advantages at times of

320

KIRTLEY F. MATHER

crisis without long antecedent training which paved the way to
their success. In the stream of life, the cataracts and rapids
are but spectacular manifestations of the fundamental forces
which gain their ends effectively in the slowly moving reaches
where the quiet waters irresistibly flow.

There is a wide-spread opinion ‘That the idea of the con-
tinuous development of the life of man* on the earth was some-
thing foreign to the mind of Jesus; the idea of catastrophe, it is
contended, was ever present to him. On the wreck of the world
his Messianic kingdom was to be established.^’ It is the view
held, consciously or unconsciously, by the' great majority of
churchmen throughout all Christendom. Opposed to it is the con-
cept, rapidly gaining adherents in the present generation, that the
Man of Galilee put no trust in destructive revolutions, but had
a firm and sure faith in the evolutionary forces quietly operating
within the lives of men. The issue is sharply defined. Did
the Great Teacher instruct his hearers in the dogma of revolu-
tion or in the doctrine of evolution, in the necessity of world-
destroying upheavals or in the efficacy of quietly progressive
growth, in the purification of the world by fire and sword or in the
attainment of man’s high destiny along the less spectacular
roadway of spiritual and mental development?

Consider for a moment the remarkable assemblage of the
“Parables of the Kingdom” in the thirteenth chapter of
Matthew’s gospel. Here are intermingled the evolutionary
parables of The Sower, The Mustard Seed, The Leaven, each
with its unmistakable emphasis on growth, development, prog-
ress from within, and the revolutionary parables of The Tares
and The Net with their references to the harvest time of reward
and destruction, to the end of the world in catastrophe and up-
heaval. The Founder of Christianity was a master in the art of
finding and clinging to the happy medium of carefully balanced
judgment. Never was he guilty, as have been so many of his
followers, of pushing a great truth to a ridiculous extreme. And
upon this greatest of Christian themes he has carefully chosen

KE VOLUTION VS. EVOLUTION

321

and maintained the middle ground. Progress, even to the
attainment of the new heaven and the new earth, even to that
glad day when all men shall be enrolled in the kingdom of heaven,
is the result of growth and evolution; but the long summer of
development bears fruit in the autumn of harvest; the era of
quiet progress paves the way for a climax of fruition; long ages
of slow preparation, so slow and inconspicuous as to appear
negligible to the superficial observer, finally achieve results
with startling suddenness. Lest his hearers spring to arms with a
frenzied desire to sweep their fellowmen without delay into
his new kingdom under penalty of death if they refuse to enter
there, he calmly, dispassionately speaks of the seed-time and
the leaven, the gradual growth of the tree and the long summer
of increase. Lest they become impatient of delay, discouraged
with the apparent paucity of achievement, he turns their atten-
tion to the harvest-time when the results of growth are tested
and rewarded according to their merits, he speaks of the closing
moments of an era when the pulse of life is accelerated and pre-
paratory development attains fruition in new opportunities for
further progress.

It is as though the humble Carpenter of Nazareth had with
the student of life development surveyed the river of life and
had seen it sweeping quietly, irresistably onward to plunge in a
cloud of spray over the brink of a cataract, then to stagger for
a moment before it regains its sense of direction and slips silently
ahead into another long reach of steady movement. The
lesson from the past is clear. The progress of life has been a
result of evolution and of growth, quiet, unassuming, slow; but
ever and again progress has been revolutionary in its nature,
and by virtue of abundant preparation there has come a time of
swift attainment, a climax of success. Revolutions in the past
have been truly catastrophic for those organic strains whose
preparation has been inadequate, but in the progress of life
as a whole they have been merely minor incidents, a quicken-
ing of the pulse, an acceleration of the continuous process of
evolution.

322

KIRTLEY F. MATHER

V

From the paleontologist’s vantage point on the reviewing
stand, the creatures of the earth appear in this twentieth century
to be approaching another milestone in their progress. There
are rapids and cataracts just ahead; once again^ the stream
of life is gathering its energies to leap forward with increasing
velocity until it plunges swiftly over the brink of another falls.
A crisis in life development, fully as critical as those which
opened and closed the Age of Reptiles, is close at hand. Survi-
val values once again have changed, but the same principles
which selected certain groups of animals to weather those
^devolutions” of the past will doubtless guide certain of the
existing creatures through the dangers in the offing. The
crisis recorded in the rocks of latest Paleozoic Age, was forced
upon the land animals by changes in climate and environment;
it was successfully passed by creatures who specialize in the
adaptation of their bodies to cold and drought, and who escaped
from the crowded confines of the sea to the almost uninhabited
silences of the land. The ^devolution” involved in the de-
thronement of the reptiles and the exaltation of the mammals
at the close of the Mesozoic Era was likewise precipitated by
external changes over which the mammals themselves had no
control; it bettered the condition of creatures who specialized
in the care of their young and the use of their brains. Each
group which prospered had for some time displayed the very
characteristics which proved efficacious in the time of stress;
the ^devolution” afforded the opportunity for the testing and
the rewarding of the products of progressive evolution.

The crisis of tomorrow, already imminent, is likewise in its
real essence the result of external conditions over which man
has so far displayed no control. The world has lost its corners
and shrunk into a neighborhood; but man is not to blame be-
cause ocean highways link its farthest islands, and mountain
barriers fail to subdivide its lands. The resources of the earth
are proving inadequate to support a large population of idle
rich or idle poor, without an excessive load being placed upon the

REVOLUTION VS. EVOLUTION

323

workers; but it is not the fault of man that the stores of iron ore
are limited, and the acres of tillable land are i^umbered. As
in the past, so in the twentieth century, the impelling forces of
progress are inherent in the environment; the response must
be dependent upon virtues intrinsic in the creatures who are to
be thus tested. Some will undoubtedly be found wanting; for
them the penalty has always been either extinction or stagna-
tion. Others — and in the past it has generally been a minority —
will respond with habits that will prove to be their salvation;
they, and they alone, will profit by the revolution.

To prophecy is always to incur the danger of post-mortem
pillorying. But it requires no unusual acumen to see that this
next milestone in the progress of life will be safely passed only
by those who specialize in the art of cooperation, as opposed to
selfishness, and in the practice of kindly thoughtfulness for
others, regardless of their color, race or creed.

SUBJECT AND AUTHOR INDEX

VOLUME XIX

Acrolichas 72

Acrolichas (?) shideleri 73

Actinoceras amundseni 289

cf. tenuifilum centrale 295

parksi 297

sp 287, 291, 292 '

tenuifilum 284

tenuifilum centrale 293

tenuifilum ursinum 296

‘^Additional Notes on, Brassfield Echinodermata.’’ By Frank Springer.... 81

Alidade, adjustment of the 137

care of the 141

description of the 98

manipulation of the, curvature and refraction 135

to determine bearing 105

to determine differences in elevation 120

to measure distance Ill

Alunite 39

“America’s Advance in Potash Production.” By W. C. Ebaugh 33

Amphilichas cucullus 214

Bathyurus spiniger 222

Beatricea gracilis 195

Botryocrinus 21

Brockocystis nodosarius 5

Bumastus holei 214

rowleyi 215

Calymene abbreviata 74

breviceps 78

cedarvillensis 78

niagarensis 78

sp. (Lorraine form) 75

sp. (West Union form) 77

retrorsa minuens 76

Calyx of unknown species of crinoid, base of 14

Castle, William E. “Education for Scholarship” 225

Ceraurinus cf. trentonensis 216

325

J

326 INDEX

Ceraiirus cf. bispinosus 216

plattinensis , 217

Chamberlain, Clark W. ‘‘Foreword’’ * 1

Clarkoceras holtedahli 261

Clidochirus 15

Clidochirus ulrichi 17

Clitambonites cf. diversus 196

Comarosystites shumardi 195

Conularia 210

Conularia heymani 208

Cornulites flexuosus 195

“Crinoid” stem, coiled 10

Ctenodonta of gibberula group 205

Cyclendoceras annulatum 299

Cyclendoceras or Dawsonoceras 301

Cyrtolites ornatus minor 206

“Cytology of the Sea-side Earwig, Anisolabis maritima Bon.” By Sidney
I. Kornhauser 234

Deltoceras (?) sp *. 272

Dimerocriniis (?) vagans 13

Diploid chromosomes of Anisolabis maritima Bon 238

Ebaugh, W. C. “America’s Advance in Potash Production” 33

“Echinodermata of the Brassfield (Silurian) Formation of Ohio.” By Aug.

F. Foerste 3

“Education for Scholarship.” By William E. Castle 225

Ellesmeroceras scheii 265

Encrinurus hillsboroensis 80

ornatus 79

Endymionia bellatula 218

Eremoceras syphax 263

Euconia (?) quebecinsis 260

Eurystomites (?) boreale 302

Foerste, Aug. F. “Echinodermata of the Brassfield (Silurian) Formation

of Ohio” ; 3

“Notes on Arctic Ordovician and Silurian Cephalopods; Chiefly from

Boothia. Felix. — King William Land, Bache Peninsula, and Bear

Island” 247

“Notes on Isotelus, Acrolichas, Calymene, and Encrinurus” 65

“The Kimmswick and Plattin Limestones of Northwestern Missouri”. . 175

“Foreword.” By Clark W. Chamberlain 1

Gonads of Anisolabis maritima Bon 237

Graphic recording of speech vibrations; new types of apparatus 90

Graphic recording of speech vibrations; the perfecting of existing types of
apparatus 83

INDEX

327

Holopea cf. concinnula 206

cf. parvtila 207

Hormotoma gracilis angustata 207

(?) major 207

Hyolithes baconi 211

miseneri 212

Isotelus brachycephalus 65

Kellogg, Robert James. “Some Suggested Experiments for the Graphic

Recording of Speech Vibrations” 83

Kionoceras holtedahli 273

kentlandense ' 277

laqueatum 273

sp 276

trentonense 275

Kornhatjser, Sidney I. ‘‘The Cytology of the Seaside Earwig, anisolabis

maritima Bon, Pt. 1.” 234

Lepadocystid, an unknown Brassfield 9

Leurorthoceras chidleyense 282

hanseni 278

Lewis, Thomas A. “Psychological Factors in Vocational Guidance” 147

Maclurina manitobensis 207

Maclurites 208

Mather, Kirtley F, “Revolution vs. Evolution: The Paleontologist

Renders His Verdict” 307

“The Manipulation of the Telescopic Alidade in Geologic Mapping”. . 97

Mather, Kirtley F. and Mehl, Maurice G. “The Importance of Drainage
Area in Estimating the Possibilities of Petroleum from an Anticlinal

Structure” 143

Mcewanella 197

Mcewanella raymonde 198

Mehl, Maurice G. See Mather and Mehl 143

“Some Factors in the Geographic Distribution of Petroleum 55

“Some Suggestions for Indicating Drilling Operations” 169

“The Use of Models in the Interpretation of Data for Determining the

, Structure of Bedded Rocks” 157

“The Use of Outline Charts in Teaching Vertebrate Paleontology” 47

Mesopalaeaster (Hemipalaeaster) schucherti 22

Myelodactylus (Eomyelodactylus) rotundatus 19

Nilus sp 219

“Notes on Arctic Ordovician and Silurian Cephalopods; Chiefly from Boothia
Felix — King William Land, Bache Peninsula, and Bear Island.” By

Aug. F. Foerste 247

“Notes on Isotelus, Acrolichas, Calymene, and Encrinurus.” By Aug. F.
Foerste 65

328

INDEX

Orthoceras sp 3O5

with vertical color bands 212

Parallelodus obliqua 206

Parastrophia hemiplicata 19S

Platystrophia shepardi 199

Platymerella manniensis 223

Potash, Inorganic sources of 37

Organic sources of 41

Proetus undulostriatus 219

Protocycloceras cf, lamarcki 270

lamarcki 269

• whitfieldi 270

‘'Psychological Factors in Vocational Guidance.” By Thomas A. Lewis. .. 147
Pterygometropus cf. lincolnensis 220

Rafinesquina deltoidea 200

Remopleurides missouriensis ; 220

“Revolution vs. Evolution: The Paleontologist Renders His Verdict.” By

Kirtley F. Mather 307

Rhynchotrema rowleyi 201

Schizocrania filosa 202

Schuchertia magna 26

“Some Factors in the Geographic Distribution of Petroleum.” By Maurice

G. Mehl 55

“Some Suggested Experiments for the Graphic Recording of Speech Vibra-
tions.” By Robert James Kellogg 83

“Some Suggestions for Indicating Drilling Operations.” By Maurice G.

Mehl , 169

Sonograph, description of 93

Sonoscope, description of 91

Spermatocyte Chromosomes of Anisolabis maritima Bon 240

Springee, Frank. “Additional Notes on Brassfield Echinodermata” 81

Spyroceras bilineatum 213

Stasfurt Deposits 34

Stereoaster squamosus 28

Strophomena cf . incurvato 202

Structure Models, advantages of 164

the construction of 162

Tetradium fibratum 194

“The Importance of Drainage Area in Estimating the Possibilities of Petro-
leum Production from an Anticlinal Structure.” By Kirtley F. Mather
and Maurice G. Mehl 143

INDEX

329

“The Kimmswick and Plattin Limestones of Northeastern Missouri.” By

Aug. F. Foerste 175

“The Manipulation of the Telescopic Alidade in Geologic Mapping.” By

Kirtley F. Mather 97

“The Use of Models in the Interpretation of Data for Determining the Struc-
ture of Bedded Rocks.” By Maurice G. Mehl 157

“The Use of Outline Charts in Teaching Vertebrate Paleontology.” By

Maurice G. Mehl 47

Trematis huronensis 203

Tripteroceras cf. planoconvexum 213

Zygospira deflecta 204

nicolleti 199

>;n

JOURNA

OF THE

SCIENTIFIC LABORATORIES

DENISON UNIVERSITY

EDITED BY

KIRTLEY F. MATHER

VOLUME XX
1922-1924

GRANVILLE, OHIO

Published

November, 1922; June, 1923 ; December, 192i

CONTENTS OF VOLUME XX

1. A Review of the Biology of Sex-determination. By Sidney I. Korn-

hauser 1

2. The Meander Patterns of Rios Secure and Mamore, Eastern Bolivia.

By Kirtley F. Mather 22

3. Primitive Musical Instruments of the Denison Collection. By Karl

H. Eschman 28

4. Notes on Medinan, Niagaran, and Chester Fossils. By Aug. F.

Foerste 37

5. The Egg and Larva of Hesperia juba Bdv. By A. W. Lindsey 121

6. The Occultation of Venus by the Moon on January 13, 1923. By P.

Biefeld : 127

7. A Botanical Survey of the Campus of Denison University. By

Dwight Munson Moore 131

8. The Underground Migration of Oil and Gas. By Kirtley F. Mather.. 155

9. Trichoptilus pygmaeus Wlsm. and the Neuration of the Family

Pterophoridae. By A. W. Lindsey 187

10. Notes on American Paleozoic Cephalopods. By Aug. F. Foerste 193

11. A Report on the Theory of Relativity. (Einstein Theory). By P.

Biefeld , 269

12. Some Problems of Taxonomy. By A. W. Lindsey 289

13. Notes on the Geology of Giles County, Virginia. By George D.

Hubbard and Carey G. Croneis 307

Subject and Author Index 379

DENISON UNIVERSITY
BULLETIN

Volume XXII, No, 5

Journal

OF THE

Scientific Laboratories

Volume XX Articles 1-3 Pages 1 to 36

1. A Review of the Biology of Sex-determination. By Sidney I.

Kornhauser 1

2. The Meander Patterns of Rios Secure and Mamore, Eastern Bolivia.

By Kirtley F. Mather . 22

3. Primitive Musical Instrum*ents of the Denison Collection. By Karl

H. Eschman 28

GRANVILLE, OHIO

NOVEMBER, 1922

The University Bulletin is issued bi-monthly and is entered at the
Post Office in Granville, Ohio, as mail matter of the Second Class

JOURNAL

OF THE

SCIENTIFIC LABORATORIES

OF

DENISON UNIVERSITY

Edited by

KIRTLEY F. MATHER

Permanent Secretary, Denison Scientific Association,
Granville, Ohio

The entire file of volumes 1 to 13 was destroyed by fire; no publications issued prior to
1907 are now available. Volumes 14 to date may be obtained from the editor at $2.00 per
volume, with the exception of volume 15, the price of which is $1.00. Separate parts, as listed
below, may be purchased at the prices indicated.

VOLUME 14

Articles 1-5, pp. 1-60, Nov., 1908 $0.50

Pre-Wisconsin drift in the Finger Lake Region of New York; F. Carney. 16 pp., 4 figs.

An esker group south of Dayton, Ohio; Earl R. Scheffel. 15 pp., 6 figs.

Wave-cut terraces in Keuka Valley, older than the recession stage of Wisconsin ice; F. Carney. 12 pp., 3 figs.

A form of outwash drift; F. Carney. 8 pp., 1 fig.

State geological surveys and practical geography; F. Carney. 6 pp.

Articles 6-10, pp. 61-188; April, 1909 $1.00

Fossils from the Silurian formations of Tennessee, Indiana, and Kentucky; Aug. F. Foerste. 56 pp., 4 plates
Studies on Babbit and other alloys; 10 pp. J. A. Baker.

A statigraphical study of Mary Ann Township, Licking County, O. 28 pp., 15 figs. F. Carney.

Significance of drainage changes near Granville, Ohio; Earl R. Scheffel. 17 pp., 2 figs.

Age of the Licking Narrows; K. F. Mather. 13 pp., 5 figs.

Articles 11-16, pp. 189-287; June, 1909 $0.75

A spectrometer for electromagnetic radiation; A. D. Cole. 10 pp., 6 figs.

The development of the idea of glacial erosion in America; F. Carney. 10 pp.

Preliminary notes on Cincinnatian fossils; Aug. F. Foerste. 20 pp., 1 plate.

Notes on Spondylomorum Quaternarium Ehrenb; M. E. Stickney. 5 pp., 1 plate.

The reaction to tactile stimuli and the development of the swimming movement in embryos of Diemycty lus torsus,
Eschscholtz; G. E. Coghill. 21 pp., 6 figs.

The raised beaches of the Berea, Cleveland, and Euclid sheets, Ohio. F. Carney. 25 pp., 5 figs.

Articles 17-18, pp. 289-442; November, 1909 $1.00

Preliminary notes on Cincinnatian and Lexington fossils; Aug. F. Foerste. 45 pp., 5 plates.

The Pleistocene geology of the Moravia Quadrangle, New York: Frank Carney. 105 pp., 27 figs.

VOLUME 15

Article 1, pp. 1-100; March, 1910

Bulletin in commemoration of Clarence Luther Herrick.

$1.00

A REVIEW OF THE BIOLOGY OF SEX-
DETERMINATIONi

SIDNEY I. KORNHAUSER
1. PREVALENT IDEAS

The mechanism of sex-determination has been a matter of
speculation since time immemorial. Many erroneous and im-
possible ideas remain even today in the mind of the layman.
The speculations may be gathered in three groups according to
whether belief is held (1) that the sex of the offspring is pre-
determined in the egg, (2) that sex is determined at the time of
fertilization, or (3) that sex is not determined until after the
zygote has been formed.

All of the older experiments on sex-determination were based
on the third supposition. It was believed that by varying the
nutrition of the developing embryo one sex or the opposite would
result. This belief was even applied to human beings. In
experiments upon tadpoles definite results were believed to have
been attained, but we now know that the death rate in these
experiments was so large that the results may be explained by a
differential mortality.

Others held that the age or vigor of the parent affected the
sex ratio, the older or the more vigorous of the two parents
tending to impress its sex upon the offspring.

Another belief, and one still held by many, regards the fresh-
ness or staleness of the egg as important. An egg shortly after
ovulation tends to produce a female, while an egg which has
remained in the oviduct some time would tend to produce a
male.

The idea that two types of eggs are formed is not altogether
new. Thus, entirely without biological foundation, theories

1 A lecture delivered before the Denison Scientific Association in October, 1921 .

1

2

SIDNEY I. KOENHAUSER

were propounded that one ovary gave rise to male-producing
eggs whereas the opposite ovary gave rise to female-producing
eggs. Equally valid was the theory that one testis gave rise to
male-determining spermatozoa and the opposite testis gave rise
to the female-producing spermatozoa. Two sorts of eggs in
equal numbers and one type of sperm would give a 50:50 ratio ;
also two sorts of sperm in equal numbers and one type of egg
would give a 50:50 ratio.

These latter ideas are found in modern theories of sex-deter-
mination, but today they are based on an actual biological founda-
tion through the use of the microscope and breeding tests.

2. CHROMOSOMES AND SEX

Modern theories of sex-determination hold to the first and
second propositions, stated in the first paragraph of this article.
If there are two kinds of eggs, male determining and female
determining, then the sex of the individual is already fixed before
the sperm nucleus has united with the egg nucleus. At least we
may say that with the extrusion of the polar cells, the mechanism
has been brought into play. If there are two kinds of sperm,
male determining and female. determining, then sex-determination
depends on the type of sperm uniting with the matured ovum,
and we may say that sex is determined at the time of fertilization.

Our present day stand on these questions is based entirely on
direct observation, both cytological and experimental. In 1902,
McClung discovered an unpaired chromosome in the testes of
certain Orthoptera and this chromosome he called a sex-deter-
miner. This observation, together with the association of this
chromatic body with sex-determination, was of primary impor-
tance and it opened up a new era in cytological work. Volumes
have been written on the mechanism of sex-determination since
1902, and even at the present time facts on this subject are being
added almost daily.

In many groups of animals there is an unpaired chromosome
in the male, which is called the X-chromosome. This can be
seen in the somatic cells, in the spermatogonia and in the sperma-

REVIEW OF BIOLOGY OF SEX-DETERMINATION

3

tocytes (fig. 1). We now know that the X-chromosome is
paired in the female cells, both somatic and germinal. In

Diploid Group, Hale Diploid Group , Female

Fig. 1. Simplest Known Mechanism of Sex-Determination
The X-chromosome is shown as black; the autosomes are in outline

spermatogenesis the autosomes pair to form tetrads. In the
first spermatocyte division the tetrads are reduced to dyads and
the X-chromosome generally passes undivided to one second

4

SIDNEY I. KORNHAUSER

spermatocyte. In dividing again into spermatids, this second
spermatocyte (fig. 1, a) gives rise to X-bearing cells which form the
female-determining spermatozoa. The sister second spermato-
cyte which did not receive an X-chromosome gives rise to the
two male-determining spermatozoa. A zygote which receives
two sets of autosomes and two X-chromosomes is a female; a
zygote which receives two sets of autosomes and one X-chromo-
some is a male. Since in general both types of sperm are formed
in equal numbers, the chances of a male- or female-determining
spermatozoan reaching the egg in the process of fertilization are
equal, and in general 50 per cent of the resulting zygotes are male
and 50 per cent female.

The foregoing case is the simplest mechanism known. While
this is a fundamental type, still there are many variations of the
mechanism. Thus the X-chromosome may have a Y partner
in the male cells. If n = one set of autosomes in a given animal,
then we have the following combination in this case :

2 n + XY = male, and 2n + 2X = female

In the spermatogenesis of such animals, two spermatids receive an
X-chromosome and two a Y-chromosome, the latter being the
male-determining spermatozoa. In other cases the X-chromo-
some may be represented by several discrete components ; and it
may or may not have a Y-chromosome associated with it in the
male cells. Thus in Gelastocoris , an hemipteron, the male is rep-
resented by 2n + 4 X -f Y and the female by 2n -{- 8X. ^^n”

here equals fifteen, so the male diploid number is 35, and the
female diploid number is 38.

Detailed studies of the sex chromosomes have brought out
many interesting facts. The X-chromosome in some animals is
attached to a certain autosome, as in Culex or in Ascaris meg ah-
cephala. When paired, as in the female somatic cells or in
oocytes, the X-chromosomes behave similarly to autosomes in
mitosis and in the mitotic divisions and also in syndesis. Con-
trary to this, the unpaired X-chromosome of the male acts rather
unlike an autosome in the spermatocytes. It fails to form a
leptotene thread, generally appearing as a conspicuous karyo-

REVIEW OF BIOLOGY OF SEX-DETERMINATION

5

some. Very often it lags behind the anaphase autosomes in
either the first or second spermatocyte division. The Y-chromo-
some likewise often fails to form a leptotene thread. In the
growth of the spermatocyte, and in the maturation divisions,
the X- and Y-chromosomes show considerable variation in degree
of association. In the primary spermatocyte division of many
Heteroptera the X- and Y-chromosomes divide independently.
They then come into contact and separate reductionally in the
second spermatocyte division.

We may now ask how the sex chromosomes are related to the
autosomes. That the X-chromosome bears many genes for
characters having nothing to do with the process of sex is known
from breeding experiments. In the female the X-chromosomes,
except where there are differences in size, cannot be distinguished
from ordinary autosomes. Recent experiments, especially those
of Bridges on Drosophila, indicate very clearly that there are
specific sex-genes in the X-chromosome, which working in con-
junction with the genes of the autosomes are capable of producing
males or females or even intermediates in cases where the
normal relationship is upset.

We are therefore entirely rid of the older idea that the X-
chromosome is composed of a different kind of chromatin from
that found in the autosomes and that the sex of the zygote de-
pends upon the amount of X-chromatin it receives. Sex is now
put upon a basis of specific genes.

The Y-chromosome until recently has not been known to
carry specific genes for bodily characters. Indeed, this chromo-
some is generally regarded as merely a degenerate X-chromosome
which has lost its sex-genes and most of its other genes as well.
That it is essential to normal development in species ordinarily
having it present was shown in the non-disjunction experiments
of Bridges. Thus, male Drosophila without a Y-chromosome
are sterile. In size the Y-chromosome may be as large as the X or
it may be almost insignificant in comparison to it. In Enchenopa
hinotata, studied by the author, both the X and Y elements form
threads in the leptotene stage of the primary spermatocytes.
These threads are thicker than those of the autosomes and never

SIDNEY I. KOENHAUSER

conjugate laterallj^, remaining in contact merely at one end.
They are not widely removed from the autosomes in their activi-
ties and staining powers in the species. However, in other
forms, such as Anisolahis, studied by the author, the Y-chromo-
somes may exhibit entirely different staining reactions from the
X-chromosome. It may be looked upon as degenerate from a
cytological standpoint.

Fig. 2. Mechanism of Sex-Determination in which Two Types of Ova are

Produced

The Z -chromosome is shown in solid black

In many forms it is therefore not unlikely that, although there
is no sex-determining mechanism visible to us with the aid of
our best microscopes, nevertheless X and Y chromosomes exist,
the Y-chromosomes being practically equal in size to the X-
chromosomes and differing from them merely in the absence of
specific genes.

REVIEW OF BIOLOGY OF SEX-DETERMINATION

7

The reverse of the foregoing mechanism described for insects
and mammals is to be found in the Lepidoptera and the birds.
In these groups the presence of 2n + 2X or 2Z (as the sex-chro-
mosomes are here called) results in a male and 2n + X or Z
produces a female. These facts are well borne out by breeding
experiments in both groups. The cytological basis is not so
strong, for both avian and lepidopteran chromosomes are rather
difficult to study.

In the moths definite results have been reached by Seiler and
also by Doncaster, showing that two types of ova are produced.
Those which extrude the Z-chromosome in the polar cell will
when fertilized produce females, those which retain the Z-
chromosome when fertilized will produce males.

It is obvious from the diagram, figure 2, that the sex of the
zygote depends entirely upon the maturation of the ovum, the
retention or expulsion of the Z-chromosome being the deciding
factor. If in any way maturation can be controlled by factors
exerting their influence either from within the egg itself or ex-
ternal to the egg, then sex ratios may be altered from the normal
50:50. Seiler has done this in the case of moths by varying the
temperature. It also offers a possible explanation of such sex
ratios as have been obtained by Riddle in his forced breeding
experiments of doves, where females are produced in the latter
part of the season from larger eggs and males in the early part
of the season from smaller eggs.

3. COMPLICATED LIFE CYCLES

The most enlightening observations on the determination of
sex through maturation are those in the aphids and phylloxerans
studied by Morgan and von Baehr. Let us examine the case of
Aphis saliceti of von Baehr. It is well known in these insects
that fertilized eggs always produce females. During unfavorable
conditions both males and females are produced by partheno-
genesis, the males, however, always arising from smaller eggs.
It has been shown that in these small eggs (represented at the
extreme right in figure 3) a whole X-chromosome is extruded in

8

SIDNEY I. KORNHAUSER

the formation of the one polar cell, leaving in the egg 2n + X
chromosomes (five in number), and that such an egg forms a
male In the larger parthenogenetic eggs no whole X-chromosome
is extruded in the single polar egg given off, and the egg retains
2n + 2X chromosomes (six in number) and develops into a
female. In the spermatogenesis of these forms it was found
that only one secondary spermatocyte develops, that which
received the X-chromosome. Thus only two instead of four
spermatids result from a primary spermatocyte and these are

Diploid Group . Nale Diploid Group Female

r PartKiajo^enetic off 1

L one polar toc^. J

Partiieno^CTiet-ic

■produces a Female ParlFenogenetie

Produces a male

Anapliase Primary Oocyte

Degenerates

jPrimaiy Spermatocyt

■Ptima^ Spermatocyta

Secondary Spermatids Sperm.
Spermatocyte ^

TelopKase /5fc\ ! (O o'

_ 'I 2-P„WlWy

Fig. 3. Scheme of Reproduction of Aphids and Phylloxerans

female-determining spermatozoa. In this case of the phyllo-
xerans and aphids it would thus appear that maturation is in
reality controlled by the size or composition of the egg.

It is rather unfortunate that the rotifers and daphnids are not
such favorable cytological material as the homopterans for it is
not at all unlikely that their sexual cycles rest upon a basis
similar to that above described. In rotifers and daphnids the
biological conditions are almost identical with those of the aphids
and phylloxerans. Fertilized eggs give rise only to females,

EEVIEW OF BIOLOGY OF SEX-DETERMINATION

9

whereas parthenogenesis may result either in females or males,
the latter coming from smaller eggs. This is all the more inter-
esting because both Whitney and Shull, working on rotifers, have
by external conditions been able to alter the normal cycle and to
cause the discontinuance of parthenogenesis, thus bringing on
the production of male individuals and eggs which require fertili-
zation. They have evidently through these conditions influenced
the type of egg produced. The type of egg would then control
its own maturation if the case were parallel to that ot Aphis
and Phylloxera.

In the Cladocerans, where parthenogenesis alternates with a
sexual cycle and at least three kinds of eggs are produced (thick
shelled, fat laden, ephippial eggs which must be fertilized; thin
shelled, glycogen laden, parthenogenetic eggs, developing into
females; and thin shelled, smaller parthenogenetic eggs, develop-
ing into males), the type of egg produced may be influenced by
temperature and food, as was shown by Geoffrey Smith. It is
not improbable that we may yet see in the maturation of these ova
differences in chromosomal behavior correlated with each type
of ovum and the sex of the resulting offspring.

Closely allied to the foregoing problem is the question of sex
determination in the Hymenoptera. Even before chromosomes
were known, Dzierzon postulated that m.ales (drones) were formed
from unfertilized eggs and females (workers and queens) from
fertilized eggs. This has been substantiated nicely, both from
cytological and genetical investigation. Newell showed in bee
matings of Italian (grey) queens and German (dark) drones, and
also in reciprocal crosses, that the male offspring of such matings
were purely maternal while the females were hybrid in character.
Cytological observations by Petrunkevitch and Nachtsheim have
also established the validity of the Dzierzon theory. Coupled
with this, observations on the spermatogenesis of Hymenoptera
have revealed interesting results. The spermatogonia possess
* merely the haploid number of chromosomes. In order that this
number be not further reduced in the process of spermatogenesis
only one division of the chromatin takes place. In the bee the
first spermatocyte division results in all the chromatin passing

10

SIDNEY I. KORNHAUSER

to one centrosome; a minute degenerate non-chromatic globule
is formed at the other pole of the spindle. In the second matura-
tion division, the chromatin divides, but one of the spermatids
is very small and degenerates. Thus only one instead of four
spermatids is formed, and it contains the haploid number of
chromosomes. Variations of this process are found in other
Hymenoptera, resulting frequently in two spermatids from the
larger second spermatocyte, each possessing the haploid number
of chromosomes.

The possibilities of sex production through parthenogenesis are
many. Reduction to the haploid number, or the elimination of
a whole X-chromosome, may produce a male, whereas the elimi-
nation of one maturation division may allow the egg to retain
the diploid number and develop into a female. Still further
possibilities are offered in cases where either the retention of the
Z-chromosome or its elimination is of vital concern in the
resulting offspring. Goldschmidt has reared both sexes from
unfertilized moth eggs.

4. POLYEMBRYONY

Closely allied to the subject of the chromosomal basis of sex
are the facts of polyembryony. Where more individuals than
one are formed from an ovum they are almost invariably of the
same sex. The classical examples are parasitic Hymenoptera,
principally of the families Procotrypidae and Chalcididae, where
often thousands of individuals result from a single egg. Other
examples are the quadruplets formed in the nine-banded armadillo,
and identical or monochorial twins in man and other mammals.
In the case of mammals the type of sperm (either with or without
an X-chromosome) is undoubtedly the deciding factor. Pro-
viding then that all the chromosDmes of the zygote divide nor-
mally, the sex of the resulting individuals must be the same,
and they will be genetically identical. In the Hymenoptera the
sex will depend entirely on fertilization or parthenogenesis. A
fertilized egg will result in females and an unfertilized ovum in
males. Patterson has occasionally got one or a few males in a

EEVIEW OF BIOLOGY OF SEX-DETERMINATION

11

female brood, but these he explains on the basis of an imperfect
mitosis, resulting probably in the loss of a specific chromosome
which probably bore the sex-determining genes. This supposi-
tion is based on direct cytological observation. The facts of
polyembryony offer a strong substantiation to the idea of
chromosomal determination of sex.

5. SEX-LINKED INHERITANCE

The association of Mendelian characteristics with particular
chromosomes is nowhere better shown than in the group of the
sex-linked characteristics. The genes for these characteristics,
of which alone thirty odd are known for Drosophila , are un-
doubtedly located in the sex chromosomes, and their inheritance
follows the distribution of these chromosomes exactly.

Let us take for example the inheritance of red eye in Droso-
phila, a dominant sex-linked characteristic (see fig. 4). If a
red eyed female is mated to a white eyed male, the are all red
eyed. If the F^ are again inbred, the F^ generation are three
red eyed to one white eyed, but the peculiar thing is that all the
white eyed individuals are males. Thus, half the F^ males are
like their grandfathers. White-eyedness is covered up when the
gene for red is present, and this is the case in all the F^ females.
However, the eggs of the F^ female, which eliminate the red gene
in the polar body in maturation and are then fertilized with a
sperm bearing a Y-chromosome, will result in white eyed offspring.
Thus we can say that the males have inherited their white eyes
from their mothers through the X-chromosomes which she con-
tributed to the zygotes.

Let us now examine the cross reciprocal to that given first.
As shown in figure 5, we get an entirely different result. The
F^ females are red eyed like their fathers, and the males are white
eyed like their mothers. In the F^ generation half the males
and half the females are white eyed and the others red eyed.
This result is due to the fact that the male has a mechanism
(only one X-chromosome) capable of bearing the gene for red
but once. This is a cross therefore of a heterozygous dominant

12

SIDNEY I. KORNHAUSER

male (red eyed) back to a recessive female (white eyed) and
gives a 1:1 ratio. The females (which must have two X-
chromosomes) all received an X-chromosome from their father
and are red eyed. The males all received their single X-
chromosome from their mothers and are white eyed.

Red Eyed Female White Eyed Male

XX X Y

G-ametes and Combinations

X X

X Y

F*

X X

Red Eyed Females

Gametes and

X Y

Red Eyed Males
Combinations

F3

(1) (2) (3)

XX XX X Y

Red Eyed Females Red Eyed

Males

(4)
X Y

White Eyed
Males

Fig. 4. Diagram Showing Sex-Linked Inheritance in Drosophila

An underscored X represents an X-chromosome bearing the gene for red eye ;
because this is dominant over white eye, any individual with an underscored X
will have red eyes.

This criss-cross type of inheritance has long been known in
man. Color-blindness is perhaps the best known illustration
and behaves in its inheritance exactly like red eye in Drosophila,
That color-blind females are so rare is due to the fact that nor-
mal color vision is dominant over color-blindness, thus XX and
XX are females with normal color vision; but the latter is a
carrier for color-blindness. XY is a normal male and XY a
color-blind male. The mating of a female carrier with a color-

REVIEW OF BIOLOGY OF SEX-DETERMINATION

13

blind male would result in the production of 50 per cent color-
blind females as shown in the diagram, figure 6.

In animals in which the female is heterogametic (Lepidoptera
and birds) sex-linked characteristics are likewise known to exist.
In fact the first sex-linked characteristics were discovered in
moths by Doncaster. In these cases it is the female which
possesses the mechanism whereby the character in question can
only be present once. Let us take, for example, barring, a

White Eyed Female
X X

Red Eyed Male
X Y

Gametes and Combinations
X X

X X

Red Eyed Females

Gametes

F*

X Y

White Eyed Males
and Combinations

(1)

XX

Red Eyed
Females

ps

(2) (3) (4)

XX X Y X Y

White Eyed Red Eyed White Eyed
Females Males Males

Fig. 5. Diagram Showing Cross Reciprocal to that Shown in Figure 4

dominant sex-linked trait in poultry. As shown in figure 7,
the F2 generation results in three barred to one black, but the
black individuals are all females.

The reciprocal cross likewise shows that the character for
barring follows the distribution of the Z-chromosome. As
indicated in figure 8, the males are barred because they got
a Z-chromosome from their maternal side; the F^ females are
black because their lone Z-chromosome came from the paternal
side.

14

SIDNEY I. KORNHAUSER

6. SECONDARY SEXUAL CHARACTERISTICS AND HORMONES

The primary difference between the sexes is in the formation of
gametes. The female is an egg producer, the male a sperm pro-
ducer. In many animals, especially invertebrates, it is very
difficult to distinguish males from females without first examining
the gonads. On the other hand there is no lack of forms in which
one can with ease distinguish the sexes by external appearances.
Sometimes this sexual dimorphism extends to all parts of the
organism. Compare the minute male of Bonellia with the female,
hundreds of times its size, for example.

Female Carrier
X X

Color-blind Male
X Y

Gametes and Combinations

F*

(1) (2)

Females

XX XX

Carrier Color-blind

(3) (4)

Males

X y X Y

Normal Color-blind

Fig. 6. Diagram Showing Sex-Linked Inheritance in Man

An underscored X indicates the presence of the gene for normal color vision;
because this is dominant over its allelomorph, color-blindness, any individual
with an underscored X has normal color vision.

Very often, however, the dimorphism is confined, first, to the
genitalia or to accessory apparatus used in copulation, oviposi-
tion or rearing of the young, and, second, to extragenital charac-
teristics not associated directly with reproduction, color and
ornaments and the like. Both of these classes are, however,
secondary to gamete production. In mammals and birds these
so called secondary sexual characteristics are found to be largely
dependent for their proper development on the normal presence
and activity of the gonad. The castration of young male mam-
mals results in individuals lacking in many ways the attributes

REVIEW OF BIOLOGY OF SEX-DETERMINATION

15

of normal males. In cattle and horses the individuals are
docile compared with the fiery males. They lack the thick neck
and put on fat more readily than males. In man, the voice
fails to change, the epiphyses of the bones fail to fuse, the beard
is weak, and the spirit dulled. Females deprived of ovaries
early in life fail to develop normal mammary glands, and the
skeletal characteristics likewise are much altered. Extensive
experiments have proved that in birds and mammals secretions

Barred Male

Z I

Black Female
Z 0

Gametes and Combinations
Z Z

Z 0

S z

Barred Males

Z 0

Barred Females

Gametes and Combinations

ps

U) Males (2) (3) Females (4)

Z2 ZZ ZO ZO

Barred Barred Barred Black

Fig. 7. Diagram Showing Sex-Linked Inheritance in Poultry

An underscored Z indicates the presence of the gene for barring; because this
is a dominant gene, any individual with an underscored Z will be barred.

of the gonads are essential to normal development. , The castra-
tion of young male rats followed by the ingrafting of ovaries
causes these individuals to be feminized. They develop mam-
mary glands, have female characteristics of skeleton and hair
pattern, and also possess female sexual instincts.

Perhaps no better case of hormone influence is known than
that of the freemartin, adequately explained through the observa-
tions of Lillie. He found that in cattle, when the chorionic

16

SIDNEY I. KORNHAUSER

coverings of twin embryos of opposite sex fused so that the blood
vessels anastomosed, the more rapidly developing male embryo
sent out hormones into the common circulation which inhibited
the normal development of the female embryo. The much
modified female embryo might then be born as a freemartin.
Even the ovaries show considerable alteration and tend to form
tubules quite like those of a testis.

In birds the activity of the gonads likewise controls to a large
extent the development of secondary sexual characteristics.

Black Male Barred Female

Z Z Z 0

G-ametes and Combinations “

Z* Z

^ z Z 0

Barred Males Black Females

Gametes and Combinations
Z

(1) Males (2)

Z Z Z Z

Barred Black

(3) Females (4)

Z 0 Z 0

Barred Black

Fig. 8. Diagram Showing Cross Reciprocal to that Shown in Figure 7

This has been nicely demonstrated by Goodale and Morgan in
castration and transplantation experiments on ducks and fowls.
Most striking is the case of female birds, which, when castrated
while still young, develop the male plumage and posture.

The whole problem of sex hormones is very complicated, for
it has been shown that the secretion of the gonads is merely one
link in the chain of factors, and that other endocrine glands con-
tribute to form a complex of factors, which controls to a large
extent the expression of the genes for the secondary sexual

REVIEW OF BIOLOGY OF SEX-DETERMINATION

17

characteristics. In the development of sex in vertebrates, the
genes for the production of sex-hormones are probably second
only in their importance and in their evolution to those genes
which determine whether ova or sperm shall be formed in an
individual.

It has been clearly demonstrated that the genes for the secon-
dary sexual characteristics lie in the autosomes and therefore
each sex has also a double set of those for the opposite sex. the
expression of one set or the other will depend on the sex genes.
Thus for example in cases where the male is heterogametic, the
presence of a single X-chromosome in all the cells of the indi-
vidual, together with the normal secretion of the male gonads,
causes the male genes for the secondary sexual characteristics to
develop. By castration and transplantation of ovaries into an
immature individual, the normal condition may be upset, and the
female secondary sex genes brought into action, as in Steinach’s
feminized rats.

It has been well demonstrated in insects that castration even
of very young individuals produces no effect upon the secondary
sexual characteristics when the animal reaches its adult form.
Even the implantation of gonads of the opposite sex results in
no change. The growth and development of the soma seems
fixed by its chromosomal complex and not alterable by any sex-
hormone. This rigidity of sexual development in insects may
be coupled with the fact that normal hermaphroditism is ex-
tremely rare in this group.

Crustacea and insects, when parasitized, may show alterations
of the secondary sexual characteristics,, especially in the case of
the males which then appear externally like females. In the
Crustacea the best case is perhaps that of Inachus, described by
Smith. The parasitized male becomes similar to the normal
female in the form of its claw, abdomen, and abdominal appen-
dages. Among insects Thelia himaculata, described by the au-
thor, is a most striking example. Parasitized males resemble
females even to the minute structure of the chitinous integu-
ment. Such alterations are most likely due to an entire upset of
the metabolism of the host and the internal environment is such

18

SIDNEY I. KORNHAUSER

that the genes for the male secondary sexual characteristics
fail to find the necessary conditions for their expression in the
developing soma.

7. GYNANDROMORPHS AND MOSAICS

In insects and Crustacea there occasionally appear abnormal
individuals which are mixtures of male and female individuals.
Sometimes the demarcation is exactly median, one half being
male, and the other half female. These are true gynandromorphs.
There are, however, cases where the division is dorso-ventral or
anterio-posterior, and again the individual may be a ^ ^patch-quilt’^
of male and female parts, these latter being mosaics or intersex
individuals such as described for moths by Goldschmidt and for
daphnids by Banta.

Insect gynandromorphs do not necessarily have the gonad of the
corresponding sex in their respective halves, showing that the
soma is not moulded by sex hormones. The cause of gynan-
dromorphism was studied by Boveri and also by Morgan. Bo-
veri claimed for gynandromorph bees of crossed races that the
male half was maternal, and the female half hybrid. If after
the division of the egg nucleus a sperm united with one of the
two daughter nuclei, that half would be female, whereas the
sister nucleus developing parthenogenetically would form a
male half which would be purely maternal. This explana-
tion holds good for some cases, but Morgan finds in Drosophila
that the male portions often bear paternal characteristics due
to genes lying in chromosomes other than the X-chromosome.
He, therefore, concludes .that at times an X-chromosome is lost
in the mitosis of a (female) zygote, and the nucleus which fails
to get two X-chromosomes develops into the male portion of the
gynandromorph. A misplaced X-chromosome in a primary
germ cell may cause testes to form in a female. Such a case was
found in Thelia where an actual chromosome count proved an
X-chromosome to be missing in all the countable metaphase
plates. The soma of the individual was purely female, however.

It is rather difficult to offer any simple mechanical explanation
for the mosaics or sex intergrades of moths and daphnids. Gold-

REVIEW OF BIOLOGY OF SEX-DETERMINATION

19

schmidt has attempted to explain his results upon a quantitative
basis, assigning values for the determiners for maleness and
femaleness together with the postulation that the strength of
these determiners varies in different races. Thus, the crossing
of a strong male race with weak male races brings about an up-
set of the normal conditions and establishes a balance of factors
where neither one sex nor the other predominates, and thus we
get the expression of two sets of genes in various parts of the
organism. Bridges’ recent work on inter sex forms in triploid
races of Drosophila would indicate that where the normal rela-
tion of sex genes (located in the X-chromosome) to the autoso-
mal genes is upset, either by a preponderance of one or the other,
then sex abnormalities of many sorts may be expected.

8. HERMAPHRODITISM

One of the most obscure problems of the entire sex question
is that of hermaphroditism, the production of ova and sperm by
a single individual. This condition is found normally in many
groups of invertebrates: coelenterates, ctenophores, flat worms,
round worms, annelids, molluscs, and some Crustacea. It is,
however, the exception rather than the rule and must be viewed
as a modification of the bisexual condition necessitated to insure
insemination in animals of a less gregarious nature. Sometimes
hermaphrodites are female in form, and again they resemble
more closely males of the group to which they belong. In cer-
tain nematodes, as in Rhahdites aberrans, an occasional male
is found among thousands of hermaphrodites of female form.
Miss Kruger has shown that occasionally there is the failure of
one chromosome to become incorporated in one of the second
spermatocytes. Spermatozoa resulting from such deficient sper-
matocytes may be the cause of those occasional zygotes which
result in males. Boveri and Schleip have shown that in the case
of Angiostomum, a nematode in which hermaphroditic individuals
give rise to a sexual generation, male-determining sperm are
formed through the failure of one-half of the spermatids to in-
clude the X-chromosome. Since our knowledge of the chromo-

20

SIDNEY I. KORNHAUSER

somes in hermaphroditism is scant, it is hardly worth while at
present to speculate on the mechanism which produces such
individuals.

That the sexual tendencies of hermaphroditic forms is often
in a sensitive balance, influenced by external conditions, is shown
by the experiments of Baltzer on Bonellia and Gould on Crepi-
dula. In Bonellia there are produced minute motile larvae
with hermaphroditic potentialities. If the free swimming larvae
find the proboscis of a female Bonellia, they attach themselves
and develop into minute males after a parasitic existence of
about four days. If, however, no proboscis is found, the motile
larva sinks to the bottom and develops into a female. In this
case we may say that probably some secretion from the pro-
boscis of the female stimulates the development of the male
anlage and that this is accompanied by the suppression of the
female fundaments. Likewise the absence of the proboscis
secretion allows the female fundaments to develop while those
of the male are suppressed. Intermediates were produced by
Baltzer by allowing larvae to attach to a proboscis and then re-
moving them at intervals of less than four days. In Crepidula
plana, a hermaphroditic gasteropod which is normally a pro-
tandric hermaphrodite, Gould has shown that the presence of
older individuals in the female state of development causes the
production of sperm in small individuals nearby. Isolated small
individuals, however, omit sperm production and form ova.
Here is an animal in sensitive balance influenced by a secretion
which probably comes to it through the sea water. The prob-
lem of hermaphroditism, its mechanism and relationship to
bisexual reproduction, is well worthy of intensive study. From
such exceptions to the general rule we may hope to learn much
about the normal mechanism of sex-determination.

9. CONCLUSION

Finally, one may ask can sex ever be controlled? There seem
to be two avenues of approach. In forms in which the female
is heterogametic, external conditions may control maturation

REVIEW OF BIOLOGY OF SEX-DETERMINATION

21

and thereby sex^ as in the case of Seiler’s moths and Riddle’s
pigeons. Where^ however, the male is heterogametic, sex could
be controlled only by an agency which would differentially aid
or inhibit the progress of one of the two types of sperm in its
approach to or penetration of the ovum. The way is not closed
and the facts so far learned about sex-determination make it
seem not at all unlikely that definite control of sex will be es-
tablished for many organisms in years not far distant.

THE MEANDER PATTERNS OF RIOS SECURfi
AND MAAIORfi, EASTERN BOLIVIA'

KIRTLEY F. MATHER

The greater part of northeastern Bolivia is a lowland plain
drained by a network of streams which unite to form Rio Madeira,
one of the larger tributaries to the iVmazon. Between Guajara
Mirim and Porto Velho (see fig. 1), the Madeira crosses the
northwestern extremity of the Pre-Cambrian shield of BraziP
in a series of cataracts and rapids. The altitude of the river bed
at the first of the cascades, close to Guajara Mirim, determines
the level of the floor of the entire basin stretching from that
point to the eastern foot of the Andes of Bolivia and Peru. The
streams from the mountains debouch upon this lowland, heavily
laden with silt, and the plain is in consequence a plain of aggra-
dation. Its surface is between 600 and 1000 feet above sea level,
and slopes with remarkable uniformity and exceedingly low
gradient from the foot hills of the Andes to the head of the cata-
racts of the Madeira. Because of the uniformly low gradient
the streams which traverse this featureless plain for hundreds of
miles have developed meanders of unusual complexity and per-
fection. The opportunity which they afford for the study of old
age stream patterns is excellent.

While engaged in geological explorations for Richmond
Levering and Company in August and September, 1920, I crossed
the eastern Andes from Cochabamba to the headwaters of Rio
Chapare, and travelled overland in the foothill region to Rio
Secure.^ After a brief examination of the upper reaches of this

1 A paper presented before the Section of Geology of the Ohio Academy of
Science, April, 1922.

2 Branner, J. C., Geol. Map of Brazil, Bull. Geol. Soc. of Amer., vol. 30,
plate 7, 1919.

3 Mather, K. F., Explorations in the Land of the Yuracares, Eastern Bolivia;
Geographical Review, vol. 12, pp. 42-56, 1922.

22

BIOS SECUKE AND MAMOKE, EASTERN BOLIVIA 23

river, I travelled as rapidly as possible to Trinidad, descending
Rio Secure and Rio Mamore. The journey gave me an oppor-

tunity to map portions of the rivers and provided the data for
this paper.

The exigencies of travel made the compilation of the map of
secondary importance, and therefore the methods used in map-

24

KIRTLEY F. MATHER

ping were perforce such as would not delay progress. Trans-
portation was by means of dugout canoes, propelled and piloted
by Yuracares Indians. Directions were determined by frequent
readings of a Brunton compass; distances were approximated by
noting the interval of time which elapsed while the canoe was
on the determined bearing. The speed of the canoe had been
previously ascertained by timing it over a marked course, and,
although the methods used in making the map were obviously
crude and subject to considerable error, it is believed that the
results obtained in the main are fairly accurate.

Rio Secure, above the junction with Rio Isiboro at Puerto
Calvimonte, averages a hundred yards in width. It is a brown,
silt laden stream, sliding swiftly between banks of clay or sand,
capped with six or eight feet of rich black soil, which rise abruptly
from the water’s edge to the level of the jungle covered plain.
At low water these banks are 15 to 25 feet, high, but in the rainy
season the river brims its banks and floods the ground between
the trees of the tropical jungle. The Isiboro is nearly as large
as the Secure above the junction of the two. The Secure’s vol-
ume is therefore nearly doubled at Puerto Calvimonte. From
that point to its mouth the river averages a little over 150 yards
in width. Rio Mamore is a much larger stream, with a width of
at least a quarter of a mile at low water, between the mouth of
the Secure and the vicinity of Trinidad. A detailed map of the
lower part of the Secure and a portion of the Mamore forms
figure 2. Throughout the area of this map and for many miles
upstream and downstream beyond it, the gradient of the Secure
and Mamore is practically constant, less than half a foot per mile
of river course.

The meander patterns of the rivers, shown in figure 2, are
characteristic; curve follows curve in dizzy succession along the
tortuous stream course. The typical meander curve is not an
arc of a circle, but is formed of short sharp bends alternating with
long, comparatively straight stretches. Many times while
paddling steadily downstream we found ourselves within a hun-
dred yards or so of the place where we had been an hour before.
Occasionally we noted cut-offs where during the previous rainy

RIOS SECURE AND MAMORE, EASTERN BOLIVIA

Fig. 2

26

KIRTLEY F. MATHER

season the stream had straightened its course and abandoned a
long-used channel; elsewhere the river banks were reduced to a
knife-edge by the close crowding of meander loops.

Apparently there is a definite correlation between the meander
pattern and the volume of the stream; this conclusion is really
the excuse for this brief note. Where the river volume is com-
paratively small, meander curves are numerous, close-crowded,
and short. With increase in volume the curves become longer,
more widely spaced, and fewer. Three distinctive patterns are
clearly shown in figure 2. These correspond to the varied
volume of the streams involved. The Secure above its junction
with the Isiboro displays twice as many meander curves in a
given distance as are found below Puerto Calvimonte, where its
volume is nearly doubled by the accession of the Isiboro. Like-
wise the lower part of the Secure has many more meanders than
has the Mamore, much the larger of the two streams.

This change in meander pattern seems to be solely a response
to the change in volume of the rivers. The gradient is not
altered, nor is the current appreciably swifter. The change, as
indicated by the map, involves a lengthening of the straight
stretches between the short sharp curves. Possibly the greater
inertia incident upon the larger volume is the major cause of the
modification.

It is of interest to note that in this land, where transportation
routes and lines of travel are restricted to the navigable waters,
the untutored Indians are sufficiently adept physiographers to
note this correlation between river volume and meander dimen-
sions. Distances between chacras, the tiny clearings under culti-
vation along the river banks, are reported in terms of the num-
bers of “turns” in the river’s course. Thus I was told that it
would be five ^Turns’’ from the mouth of the Secure to the port
of Trinidad; biit that because the Alamore was very wide the
“turns” were very long, and it would require from sunrise to
sunset to traverse the distance.

A little later in the same field season I had opportunity to
check the conclusion, reached on the Secure and Mamore, by
similar observations on Rio Heath and its tributary, Rio Najegua,

RIOS SECURE AND MAMORE, EASTERN BOLIVIA 27

on the frontier between northern Bolivia and eastern Peru (fig. 1).
The Najegua is less than a third as large as the Secure, but its
gradient is approximately the same. In harmony with its slight
volume, its meander curves were very short, extremely close
spaced, and numerous. Working upstream in it, at a pace of 2|
miles per hour, it was necessary to take bearings every minute or
two in order to get any results at all from the effort to map its
tortuous course. Rio Heath, only slightly less in volume than the
Secure, has a meander pattern practically identical with that of
the Secure above Puerto Calvimonte.

PRIMITIVE MUSICAL INSTRUMENTS OF THE
DENISON COLLECTION

KARL H. ESCHMAN

The collection of primitive musical instruments at present
located in the building of the Conservatory of Music, Denison
University, although small in number, includes all the main types
of instrumental evolution. It is the result of miscellaneous
gifts of alumni from mission fields. The fact that this collec-
tion so completely illustrates a brief outline of the subject,
it is thought, should encourage other colleges with departments
of music, to begin collections of like character. ^ In addition, it is
hoped that a description of some of the specimens may be of
interest to students of the subject.

With the aid of certain ethnological principles, and by methods
not unlike those used in the classification by distribution, of
fossil remains in strata of different periods, an order of evolution
of musical instruments has been formulated, which may be ac-
cepted in general. In determining the priority of instrumental
types, we are hindered by the nature of the materials them-
selves. However, by collecting instruments from tribes which
represent all stages of civilization existing at present, we can
secure, of course, illustrations of many periods of construction.
It is this fact which adds to the interest of any collection, what-
ever the age of the particular instruments themselves. There
have been two opposing theories of priority: one starting with
the percussion type, and the other favoring the pipe or horn type.
Both types are so simple as to need little ingenuity for construc-
tion. Handclapping would easily lead to the beating of objects
together, and shouting through the hands would be followed by

1 The splendid collections at the University of Michigan, Yale, and Penn-
sylvania, as well as that at the Metropolitan Museum, New York, are based upon
the gift of a single large private collection.

28

MUSICAL INSTEUMENTS OF DENISON COLLECTION

29

the use of a crudely rolled horn, while natural whistles literally
grow on bushes wherever reeds and bamboo are found.

The weight of authority, however, is with the former theory,
as is also the evidence of ethnology. In fact, all seems to point to
the following arrangement, which also coincides with relative
difficulty of manufacture and complexity of idea

I. Indefinite percussion

II. Wind instruments — pipe type

III. Wind instruments — horn type

IV. Definite percussion

V. Stringed instruments — without fingerboard

VI. Stringed instruments — with fingerboard

VII. Stringed instruments — with bow, without and with fingerboard

VIII. Multipipes — organ type.

I. INDEFINITE PEKCUSSION

1. Ngoma (war drum) — Africa, This most primitive type of
drum is a section cut from a tree-trunk. Hollow trees are still
occasionally used as drums, and the attempt to make such sta-
tionary instruments portative, probably produced the first drum
of this character. This drum is 96.8 cm. in length by 34 cm. in
diameter at the largest end. The body is cut down by a sudden
shoulder to a diameter of 12.5 cm. at the smaller end. The drum
is crudely hollowed out, and this small end has an opening 8
cm. in diameter, surrounded by a tin collar but with no leather
head. This narrowing, and the small opening, even without a
head, greatly aids the sonority. The rawhide head at the larger
end is fastened to the drum by three rows of wooden pegs. Two
sets of three wooden projections and one of two, were left on the
drum when carved, to be used as handles or for thongs.

2. Ndunga — Africa. This drum is 304 cm. (9 feet 8 inches)
in length, and is interesting as one of the few drums of this type
in American collections. Drums of still larger size are made by
the natives. This tree-trunk has been trimmed with greater
care than the Ngoma above, to 26.5 cm. diameter at the large
end and 12 cm. at the smaller. Both ends are covered with hide
and are strung together by ten thongs of rawhide with hair

2 This outline has been simplified for use with illustrations selected.

30

KARL H. ESCHMAN

attached, running the entire length of the drum. It is carried by
four men, two on each side of a long handle which is carved from
the body of the tree. The drum as well as the drum-stock (32
cm. long, 2 cm. diameter) which is not padded, is painted in
alternate red and black circles.

3. Drum — Africa. A well made cylinder, 49.5 cm! in length,
26 cm. m diameter, has two heads laced, together by a very intri-
cate network of rattan which covers the entire drum. The whole
drum evidences much more skill of workmanship than the pre-
ceding, and produces a very satisfactory tone, as the tight lacing
greatly increases the resonance.

4. Ozee (stationary drum) — Burma. This drum is made of
wood in the shape of a goblet 38 cm. high and 15.5 cm. in diameter,
lacquered black and red. The head is painted with a smaller
circle of black and is fastened by thongs to a wire at the base of
the head. The wooden base of this drum is hollow. A com-
panion drum of the same general size and finish has a skin on
each end and a thong which slips around the neck, making it
possible to play with the fists while moving about.

II. WIND INSTRUMENTS — PIPE TYPE

5. Siakuhachi — Japan. This direct flute is made from a
thick bamboo stem, using the natural swell of the reed. It is
blown at one end where a piece is cut off to afford a position for
the lip. The length is 49 cm. and the diameter 1.7 cm. swelling
to 2.3 cm. There are four finger-holes in the front and one in the
back, while other smaller subdivisions of pitch are obtained by
only partly closing these holes with the fingers. There is a
distinct pattern for this type so that the distance from joint to
joint of the bamboo averages 17, 14 and 8.5 cm. respectively.
This specimen measures 18, 14 and 9 cm.

6. Traverse flute — Burma. This flute is lacquered black and
has a ring of ivory at each end; 40.5 cm. long, 2 cm. diameter.
Six holes for fingering and one for blowing.

7. Ti or Yueh — China. Seven holes in front and one in back of
pipe. The mouth-hole is divided by a small partition into two
parts. Made of bamboo, 28 cm. long, 1.5 cm. diameter.

MUSICAL INSTRUMENTS OF DENISON COLLECTION

31

8. Fife — Garo. Traverse; very small bore; reed 55 cm. long,
1.1 cm. inside diameter. The finger holes are near the opposite
end from the mouth-hole.

III. WIND INSTRUMENTS — ^HORN TYPE

9. Wooden trumpet — Africa. Total length, 87 cm. In this
horn the mouthpiece is on the side, and the actual blowing length
is 58 cm. The diameter at the large end is 9 cm. From the
mouthpiece to the open end, the horn is covered with natural
fibre and wrapped with rattan.

IV. DEFINITE PERCUSSION

10. Gong — Burma. Diameter 18 cm. with a 3 cm. edge turned
up; but slight attempt at decoration.

11. Kyizi — Burma. Two very small hollow hemispheres of
bronze through which a string is fastened, are allowed to strike
together, giving the impression of tinkling bells. These are only
3 cm. across.

12. Zanze or Biti — Africa. Eleven tongues of iron are
mounted on a hollow sound board in such fashion that they can
be plucked by the thumbs when the instrument is held in the
two hands. This instrument is akin to the marimbas but
scarcely a typical percussion type. According to the savage
notion, the twanging is made more beautiful by the rattling of
small beads on some of the tongues, when the instrument is
played. The box is 27.5 cm. by 13 and 16 cm. (flaring) and
1.5 to 3.5 cm. deep. The vibration of the other end of each
tongue is stopped by a strip of leather on the face of the instru-
ment.. The scales of no two instruments of this type are alike.
The Denison specimen gives: g' flat, f', c', a', B, A flat. A, d
flat, f, b, e'.

V. STRINGED INSTRUMENTS — ^WITHOUT FINGERBOARD

13. Gopi-Jantra, Monochord — Garo. (Tura, Assam.) A cala-
bash gourd is fitted with a skin bottom through which a single
wire is fastened by means of a button. (This use of a European

32

KARL H. ESCHMAN

button is thought highly ornamental.) A piece of bamboo is
split part way and fastened to the sides of the gourde and to this^
the wire is stretched by means of a single peg in the side. Total
height 78 cm.; diameter of body, 18 cm.; very primitive. The
pitch is changed by pressing in on the bamboo strips while the
tone is sounded.

14. Ichigenkin or Sumagota (monochord) — Japan. The one
string is stretched over a board of cherry-wood 110 cm. long and

10.5 cm. wide. The supporting ivory bridge is missing in this
specimen. The string is tuned to f^ of our scale — a note which
may be considered the principal note of the Japanese tonal-
system. All Japanese instruments are elaborately decorated.
This one has a circular piece of embroidery near the end, and is
suspended by a red and yellow cord from the other end when not
in use. When played, it is laid horizontal on a low table. The
instrument has no fingerboard, but the pitch is changed by an
ivory cylinder worn on the second finger of the left hand which is
pressed against the string to furnish nodes for the different notes.
The ivory spots or designs found on some instruments to indicate
these points, are not present in this specimen.

VI. STRINGED INSTRUMENTS WITH FINGERBOARDS

Samisen^ — Japan. This instrument has a fingerboard but no
frets. It is related to the Chinese Sanheen, each having three
strings and a long neck. The body of the Sanheen is round and
of the Samisen rectangular, in this case 20 cm. by 18 cm., 10.5
cm, thick, covered with catskin. The length of the entire in-
strument is 94 cm. The three strings are turned in three ways : —
c'^, f^, c"^, c'^, c"^; and g'^, c"^, f"^. The Samisen

is played with a large wooded pick over 20 cm. long, the
strings being struck below where the neck joins the body.
The face is strengthened there with a small extra piece of parch-
ment which receives the blow of the pick, thus producing two
sounds, the plucking of the strings and the stroke on the body.

16. Yueh Ch’in (Moon guitar) — China. This instrument
derives its name from its round shape, 33.5 cm. in diameter, and

3.5 cm. thick, both surfaces being flat. It is the first string

MUSICAL INSTRUMENTS OF DENISON COLLECTION

33

instrument on our list which gives in its construction, information
as to actual scale relationships. There are eleven very high
wooden frets, eight on the body and three on the neck. The top
one serves as a bridge and the frets decrease in height all the way
down. The four strings are tuned in pairs, and are often plucked
with the finger nails which are grown conveniently long. A
loose wire fastened inside the body jangles when the instrument
is played, and adds to the effect, somewhat as the beads do in the
African zanze.

17. Gekkin (Moon guitar)^ — Japan. A comparison with no.
16 shows the intimate connection between China and Japan.
The Japanese instruments always show much more care in
construction and beauty of ornament than the parallel type in
China. The sizes of the two instruments are almost identical (the
body of the Gekkin is 34 cm. diameter, by 3,5 cm.) but the number
and locations of the frets are different. The Gekkin has nine in
all, four on the body and five on the neck. The frets are of
ivory. Carved wooden ornaments are located about where
sound-holes might be expected on a medieval viol. A snake skin
protects the face of the instrument from the blows of the small
pick. This instrument also contains a snare.

VII. STRINGED INSTRUMENTS WITH BOW .

18. Mendicant’s fiddle — Thibet (Darjiling). This instrument
is a crude Thibetan counterpart of the Chinese urheen (19) and
in every way shows its low origin. There is only the slightest
attempt at decoration with inaccurate cross-markings on the
neck. The tuning-pegs are not mates, but evidently have been
picked up somewhere, and put to this use. The two ^ ^strings”
are simple bunches of about a dozen horse-hairs each, like those
on the bow. The evolution of bows is in itself an interesting
subject. This bow is most primitive, being simply a bent stick,
but there is a notch at one end which makes it possible to loosen
the hair when not in use. A peculiar feature of this instrument
(as of no. 19) is that the hair of the bow passes between the
strings so that the bow cannot be removed from the strings. The
body of the instrument, which corresponds in position to the

34

KARL H. ESCHMAN

head of a mallet, is a section of bamboo 10 cm. in diameter and
13 cm. long. The skin head is fastened on with wooden pegs
which project irregularly.

19. Urheen — China. This type is one of the oldest Chinese
stringed instruments. Although this specimen shows great care
in construction, having inlaid pegs and top, it is almost as primi-
tive as no. 18, because the hair of the bow passes between the
strings ; and, as the strings are too far from the neck to be stopped,
only one combination of tone is possible. The improvement
over no. 18 is mainly in the strings themselves, which can be
tuned to f ^ and c ^ . The rasping sound of this open fifth is
the only musical effect of this instrument. The bow is an
advance, having something of the contour of a modern violin
bow, but it does not seem to have been given the care bestowed
on the instrument itself. The cylindrical body 11.5 cm. long by
8 cm. diameter, is made of wood covered with a snake-skin
head.

20. Fiddle — Thibet. The body of this fiddle is made from a
cocoanut shell, with a skin head fastened down over half the
surface of the shell. A bundle of horse-hairs is stretched from
the head to a peg in the handle. The wooden bridge is not
fixed to the face of the head but is tied to the neck of the instru-
ment by a 'string, and placed in position only when the hair is
tightened. The hair of the bow does not pass between the hair
of the string in this case. An interesting feature of this instru-
ment is the fact that the maker has used part of an old flute for
the neck, placing the mouth hole near the head and leaving four
finger holes at the other end, into one of which the peg is placed.
This use of old material at hand is characteristic although un-
expected. Personal and tribal traits of this sort add interest to
any collection of primitive instruments.

VIII. MULTIPIPES — ORGAN TYPE

21. Muhso flute. — Burma. A reservoir made from a calabash
gourd has five open pipes. The open pipes make possible a
second tone from each pipe, by closing the lower holes which
open on the bottom of the gourd. Because of the difficulty of

MUSICAL INSTRUMENTS OF DENSION COLLECTION

35.

holding more than two pipes in the mouth, a substitute reservoir
was sought. In some sections a hollow lump of clay is used,
into which the pipes are fastened. No. 22 shows a further
advance.

22. Sheng — China. Seventeen reeds of small bore are set in a
lacquered cup of cherry-wood. The mouthpiece in primitive
instruments was a long spout like that* of the Muhso flute
above, but it is now a much shorter projection covered with
an ivory plate. . Each of the pipes contains a very small free
reed of copper, set level with the frame. The instrument is
played by inspiration — i.e., by drawing in the breath — as other-
wise moisture might settle on the reeds and affect the pitch.
There are many interesting features connected with this
instrument — the use of two mute pipes and the curious
arrangement of pipes which gives it the Chinese name of ^^Bird-
on-the-nest,’^ the fact that sounding length of the pipes is different
from the apparent length, and the use of a free reed at such an
early date. (The type is thought to be at least three thousand
years old.)

From the standpoint of the theory of scales there is the ques-
tion of a mechanical origin of the sheng scale procured by the
successive halving of differences, starting with the longest pipe,
which is just the length of the Chinese foot. Further, the
duplication of two notes of f ^ and g ^ by the use of four pipes,
suggests an attempt at equal temperament — i.e., the production
of true fourths with the upper and lower c sharps. The only
difference in the scale of the Denison sheng from the normal type
is that pipe no. 7 (counting from the left of the opening) gives
c" and pipe no. 11 gives c/" while in the usual instrument these
are reversed.

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE I

KARL H, ESCHMAM

MUSICAL INSTRUMENTS

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE II

KARL H. ESCHMAN

MUSICAL INSTRUMENTS

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE III

KARL H. ESCHMAN

MUSICAL INSTRUMENTS

m-

DENISON UNIVERSITY
BULLETIN

Volume XXIII, No. 4

Journal

OF THE

Scientific Laboratories

Volume XX

Articles 4-8

Pages 37 to 185

4. Notes on Medinan, Niagaran, and Chester Fossils. By Aug. F.

Foerste 37

5. The Egg and Larva of Hesperia juba Bdv. By A. W. Lindsey. . . . 121

6. The Occultation of Venus by the Moon on January 13, 1923. By

P. Biefeld 127

7. A Botanical Survey of the Campus of Denison University. By

Dwight Munson Moore 131

8. The Underground Migration of Oil and Gas. By Kirtley F. Mather 155

GRANVILLE, OHIO

JUNE, 1923

The University Bulletin is issued bi-monthly and is entered at the
Post Office in Granville, Ohio, as mail matter of the Second Class

JOURNAL

OF THE

SCIENTIFIC LABORATORIES

OF

DENISON UNIVERSITY

Edited by

KIRTLEY F. MATHER

Permanent Seeretary, Denison Scientifie Association,
Granville, Ohio

The entire file of volumes 1 to 13 was destroyed by fire; no publications issued prior to
1907 are now available. Volumes 14 to date maybe obtained from the editor at S2.00 per
volume, with the exception of volume 15, the price of which is $1.00. Separate parts, as listed
below, may be purchased at the prices indicated.

VOLUME 14

Articles 1-5, pp. 1-60, Nov., 1908 $0.50

Pre-Wisconsin drift in the Finger Lake Region of New York; F. Carney. 16 pp., 4 figs.

An esker group south of Dayton, Ohio; Earl R. Scheffel. 15 pp.. 6 figs.

Wave-cut terraces in Keuka Valley, older than the recession stage of Wisconsin ice; F. Carney. 12 pp., 3 figs.

A form of outwash drift; F. Carney. 8 pp., 1 fig.

State geological surveys and practical geography; F. Carney. 6 pp.

Articles 6-10, pp. 61-188; April. 1909 $1.00

Fossils from the Silurian formations of Tennessee, Indiana, and Kentucky; Aug. F. Foerste. 56 pp., 4 plates.
Studies on Babbit and other elloys; 10 pp. J. A. Baker.

A statigraphical study of Mai y. Ann Township, Licking County, O. 28 pp., 15 figs. F. Carney.

Significance of drainage changes near Granville, Ohio; Earl R. Scheffel. 17 pp., 2 figs.

Age of the Licking Narrows; K. F. Mather. 13 pp., 5 figs.

Articles 11-16, pp. 189-287; June, 1909 $0.76

A spectrometer for electromagnetic radiation; A. D. Cole. 10 pp., 6 figs.

The development of the idea of glacial erosion in America; F. Carney. 10 pp.

Preliminary notes on Cincinnatian fossils; Aug. F. Foerste. 20 pp., 1 plate.

Notes on Spondylomorum Quaternarium Ehrenb; M. E. Stickney. 5 pp., 1 plate.

The reaction to tactile stimuli and the development of the swimming movement in embryos of Diemyctylus torsus,

Eschschoitz; G. E. Coghill. 21 pp., 6 figs.

The raised beaches of the Berea, Cleveland, and Euclid sheets, Ohio. F. Carney. 25 pp., 5 figs.

Articles 17-18, pp. 289-442; November, 1909 $1.00

Preliminary notes on Cincinnatian and Lexington fossils; Aug. F. Foerste. 45 pp., 5 plates.

The Pleistocene geology of the Moravia Quadrangle, New York; Frank Carney. 105 pp., 27 figs.

VOLUME 15

Article 1, pp. 1-100; March, 1910 $1.00

Bulletin in commemoration of Clarence Luther Herrick.

NOTES ON MEDINAN, NIAGARAN, AND CHESTER

FOSSILS

AUG. F. FOERSTE

A. The correlation of Ohio, Indiana, and Kentucky Medinan and Niagaran

strata 37

B. The fauna of the Whirlpool sandstone of Ontario 50

C. Fossils from the base of the Manitoulin limestone at Credit Forks, Ontario. 58

D. A lower Medinan fauna below the Brassfield limestone in Ohio 72

E. The brachiopoda of the Brassfield limestone of Ohio 88

F. The gasteropoda of the Brassfield formation of Ohio 94

G. Niagaran fossils from Jeptha Knob, Kentucky 105

H. Trilobites from the St. Clair limestone of Arkansas 109

I. A new gasteropod from the Guelph formation of Ohio 115

J. A Stigmarian root from the Chester formation of Illinois 116

A. THE CORRELATION OF OHIO, INDIANA, AND KENTUCKY MEDINAN
AND NIAGARAN STRATA

In East-Central Kentucky the following Silurian strata, in
descending order, may be discriminated. ^

fEstill clay

Alger formation sWaco limestone

[Lulbegrud clay

Indian fields forma- /Oldham limestone
tion. iPlum .creek clay

Crab Orchard di-
vision of Niagaran

Medinan Brassfield formation Brassfield limestone

The so-called Waco limestone is merely that part of the Alger
formation in which a few limestone layers occur. In the type
area one of the limestone layers is from 1 to 2 feet thick. The
other limestone layers are less than 1 inch thick. Fossils occur
both in the limestone and in the clay shale. Neither limestone
nor fossils can be traced north of Indian Fields, Kentucky, and

^ Foerste- A. F., The Silurian, Devonian and Irvine formations of east-central
Kentucky: Kentucky Geol. Survey, Bull. 7, 1906, p. 27.

37

38

AUG. F. FOERSTE

farther north the collective term Alger clay is used for the con-
tinuous clay shale section forming the upper part of the Silurian
in Montgomery^ Bath, and most of Fleming county. In Lewis
county, and in the northern part of Fleming county, this Alger
clay is overlain by the Bisher member of the Niagaran. In
Lewis county the upper part of the Alger clay contains Liocaly-
mene clintoni and other fossils indicating relationship with the
Clinton of Maryland and the typical Clinton of central New York,
as exposed in the vicinity of the village of Clinton in that state.

The Oldham limestone consists of thin limestone interbedded
with thin clay shale. It contains very few fossils and of these
only Stricklandinia norwoodi has been recorded. Since this
species does not occur elsewhere than in east-central Kentucky
it is of no service in correlation. The Oldham limestone may be
followed lithologically as far north as the Rose Run Quarries,
about 7 miles east of Owingsville. Farther north it can not be
discriminated readily from the underlying Plum Creek clay
shale, since the latter there also contains thin limestone layers,
often in considerable quantity.

Throughout southwestern Ohio there is a series of very white
and fine grained limestones known as the Dayton limestone.
In Highland and Adams counties in Ohio, and in the adjacent
parts of Lewis county in Kentucky, this Dayton limestone lies
immediately beneath a thick clay shale zone regarded as the
northward extension of the Alger clay. Since the Dayton
limestone in Flighlaiid and Adams counties contains Pentamerus
oblongus, it is regarded provisionally as corresponding to one of
the so-called Clinton Pentamerus horizons of the more western
parts of New York. Possibly it corresponds approximately to
the Walcott limestone of the Clinton as exposed in the Rochester
area of New York. In that case the Dayton limestone forms
the base of that part of the Ohio Niagaran which corresponds
to the Clinton of New York, when this term is used so as to
include the Clinton of Western New York at Rochester and as
far west as Niagara Falls and southern Ontario as well as the
typical area around Clinton, New York.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

39

Nothing is known of the fossils of the Plum Creek clay shale,
at least within the area of its typical exposure. Farther north,
at the Rose Run quarries, east of Owingsville, Kentucky, a
considerable fauna once was exposed in strata overlying the iron
ore horizon. This fauna never was collected but it contained
species resembling Clathropora cUntonensis, Strophonella day-
tonensis, and other species resembling forms known in the Brass-
field limestone, but at the time this fauna was examined in the
field it was regarded as sufficiently distinct from the typical
Brassfield to be regarded as probably of Niagaran age.

The Brassfield limestone is regarded as equivalent to part of
the Medinan section in the Niagara Falls area of New York
and in southern Ontario.

At the base of the Brassfield limestone, in the quarry imme-
diately north of Lawshe, in Adams county, Ohio, Platymerella
manniensis Foerste was found in a thin horizon only a few
inches thick. ^ This occurrence is of interest because the same
species occurs at a corresponding horizon in western Illinois and
eastern Missouri." At these western localities the Platymerella
horizon is underlain, in descending order, by the Essex, Edge-
wood, and Girardeau limestones. Recently fossils have been
found in argillaceous strata underlying the typical Brassfield
limestone, in Montgomery county, Ohio. These beds are of
Silurian age and may correspond approximately to one of the
western horizons, presumably to the Edgewood limestone, as
far as may be determined from the meager data secured so far.
In that case they belong beneath the Platymerella horizon.

This lower Silurian horizon in Ohio may belong beneath the
argillaceous horizon for which the name Belfast bed was pro-
posed 27 years ago."^ At the time this name was proposed two
Silurian species were known from the top of the Belfast bed,
Haly sites catenulatus, and a form of Orthis flahellites with 44

2 Foerste, A. F., The Kimmswick and Plattin Limestones of Northeastern
Missouri: Denison Univ. Bull. Sci. Lab., vol. 19, 1920, pp. 223, 224.

® Savage, T. E., Stratigraphy^ and paleontology of the Alexandrian series in
Illinois and Missouri: 111. State Geol. Survey, Bull. 23, 1913, p. 36 of reprint.

4 Foerste, A. F., The Middle Silurian rocks of Ohio and Indiana: Jour. Cin.
Soc. Nat. Hist., vol. 18, pp. 163-166, 1896.

40

AUG. F. FOERSTE

radiating plications, probably identical with Orthis dinorthis
Foerste.'"^ These fossils suggest Brassfield afh.nities. Recently
Prof. W. H. Shideler, of Miami University, found specimens of
Whitfieldella and other fossils having a Silurian aspect in argil-
laceous strata immediately beneath the typical Belfast bed on
Beasley Fork southeast of West Union, Ohio. Their horizon
probably is the same as that of the Montgomery county speci-
mens provisionally referred to the Edgewood.

In Montgomery county, Ohio, the upper part of the Brassfield
limestone frequently contains interbedded layers of richly fossili-
ferous clay. Many fossils occur here which are unknown in
the underlying parts of the Brassfield limestone, though the
more commonly known fossils occur at both horizons. In
general, the Brassfield limestone of Ohio, Indiana, and Kentucky
appears to correspond to the Manitoulin dolomite of southern
Ontario; but the upper, more ferruginous part may correspond
approximately to the Cabot Head shale, which, in southern
Ontario, is the horizon for Rhinopora verrucosa, while the genus
Brockocystis appears limited to the Manitoulin limestone in that
province.

The name Beaver town marl was not intended to designate
the richly fossiliferous clay forming the upper part of the Brass-
field section or included in the latter locally, but it was used to
designate a soft, very fine grained deposit, an argillaceous lime-
stone, readily disintegrating under the influences of weathering,
and not a marl in any sense of the term. The term was first
used in 1885,'^ and several species, including Platystrophia re-
versata, Ctenodonta minima, Liospira affinis, Cyclora alta, Bellero-
phon exiguus, Orthoceras inceptum, and the problematical species
designated as Zygospira modesta and Trochonema nanum, were
described from this horizon. The large crinoid beads found
in this stratum were of the same type as those found in the upper
part of the Brassfield limestone, and the Beavertown marl is

5 Foerste, A. F., Fossils of the Clinton group in Ohio and Indiana: Ohio Geol.
Survey., voL 7, 1893, pL 31, fig. 4.

® Foerste, A. F., The Clinton Group of Ohio: Denison Univ. Bull. Sci. Lab., vol.
1, 1885 p. 74.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

41

regarded as merely the upper part of the Brassfield formation
in this area. A chemical analysis of this so-called marl was
published in the series of articles on the Clinton Group of Ohio,^
the term Clinton at that time being in use for the strata now
known as the Brassfield.

In the Hillsboro area, in Highland county, Ohio, the Silurian
section consists of the following strata, named in descending-
order.

Guelph dolomite
Lilley formation
Bisher formation
Alger clay shale
Dayton limestone
Brassfield limestone
Belfast formation

The term Guelph is used here merely to avoid using the term
Cedarville dolomite for strata not containing a fauna similar
to that of the Cedarville area. It does, however, contain Mega-
lomus canadensis, species of Trimerella, and other fossils known
in the Guelph of Ontario. Liospira perlata and tall species of
Coelocaulus occur.

The base of this so-called Guelph in the quarries in the eastern
part of the town of Hillsboro is formed by a Pentamerus horizon
which corresponds approximately to the Springfield dolomite
of Greene, Clarke, Miami, Montgomery, and Preble counties,
farther north in Ohio. The overlying part of this so-called
Guelph should correspond in age to the Cedarville dolomite of
the counties just mentioned, but it does not contain the same
fauna.

The Lilley formation includes that part of the section erro-
neously identified many years ago by Prof. Edward Orton, as
the Springfield stone. ^ This identification was based on the
lithological appearance of the rock, it forming a promising

’ Foerste, A. F,, The Clinton Group of Ohio; — Part IV: Denison Univ. Bull.
Sci. Lab., vol. 3, pp. 3-12, 1888.

* Orton, Edward, The Geology of Highland County; Geol. Surv. Ohio, Rep.
Progress in 1870. Published in 1871, pp. 274-277.

42

AUG. F. FOERSTE

building stone where exposed along the abandoned railroad within
the limits of Hillsboro, and in the quarry in which this railroad,
as far as finished, terminated in the eastern part of the town.

The Bisher formation corresponds approximately to the West
Union or Lower Cliff of Professor Orton, and this name would
have been retained if Professor Orton ever had described any
section from the West Union area, or had designated at Hills-
boro the same boundaries between the West Union and Spring-
field beds as those adopted later between the Bisher and Lilley
formations. It is of upper Clinton age.

Notes on Bisher and Lilley faunas were published in the Ohio
Journal of Science in the years 1917 and 1919.

The Bisher fauna can be traced southward from Hillsboro
throughout Highland and Adams counties, in Ohio, and Lewis
county, Kentucky, as far as the northern part of Fleming county
in the latter state. It has not been identified anywhere north
of Hillsboro, Ohio, but the strata immediately beneath the
Springfield limestone along the creek half a mile west of Port
William, in the area northeast of Wilmington, Ohio, appear to
contain a somewhat similar fauna. But no trace of the over-
lying Lilley fauna is to be found so far north.

As a matter of fact, the Lilley fauna appears to be very re-
stricted even in the Hillsboro area. It is known at various
quarries in the immediate vicinity of Hillsboro, at several locali-
ties southeast of Marshall, and apparently also 2 miles north of
Locust Grove, north of Crooked Creek, on the road to Sinking
Springs. It has not been identified at any other localities.

While the Bisher formation can be traced over wide areas in
Highland and Adams counties, the strata overlying the Bisher
formation present a complex of which very little is known so far.
The lithologic character of these strata changes within a few
miles on proceeding from Hillsboro eastward toward Marshall,
and many fossil horizons occur in the areas between Hillsboro,
Alar shall, Bainbridge, and the Ohio River whose relative position
remains to be determined.

Only the Bisher formation is definitely known to occur in
I.ewis county, Kentucky, though lower portions of the so-called

MEDINAN, NIAGARANj AND CHESTER FOSSILS

43

Guelph may occur there also, for instance, in those Silurian
deposits which occur west of Vanceburg on the road to Valley.

The bituminous horizons of the so-called Guelph in the Hills-
boro area may be traced northwest of the town on the road to
Wilmington, and similar strata, but without the bituminous
content, appear to occur near New Vienna, northeast of Snow
Hill, in the area between New Vienna and Wilmington, Ohio.

From Wilmington northward, however, the Niagaran section
resembles that found in Greene, Clarke, Miami and Montgom-
ery counties. Here the following section is found, in descending
order.

(Cedarville dolomite
Durbin formation j Springfield dolomite
[Euphemia dolomite

^Taurefi’ limestone
^Hsgood” clay shale
Dayton limestone
Brassfield limestone
Belfast bed.

In this section the strata called the Euphemia dolomite are
those included by Professor Orton in his West Union bed when
using that name for the tier of counties here named. It is the
Mottled bed of Professor Prosser. It is fre€(uently exposed
between Springfield, Ohio, and Lewisburg, in the western part
of the state, but is unknown at Cedarville, where the lowest
dolomitic rock in the gorge half a mile west of town belongs to
the Springfield horizon.

Immediately beneath this Springfield dolomite,* fin the gorge
west of Cedarville, there is a clay shale, of which a thickness of
scarcely 6 feet is well exposed, the basal part not being seen.
This clay shale contains, at a level 2 feet below its top, Strepte-
lasma radicans Hall, Eucalyptocrinus crassus Hall, Schuchertella
subplana (Conrad), Leptaena rhomhoidalis (Wilckens), Plecta7n~
bonites transversalis (Wahlenberg), Dalmanella elegantula (Dal-
man), Spirifer radiatus (Sowerby), Atrypa reticularis iiewsomen-
sis Foerste, Dictyonella reticulata (Hall), Strophostylus sp., and
Dalmanites verrucosus (Hall). This is a Waldron fauna.

44

AUG. F. FOERSTE

The Springfield dolomite in the Springfield area contains
relatively few fossils aside from Pentamerus oblongus and Caly-
mene celehra Raymond. However, at the Jackson quarry, several
miles south of Covington, Ohio, the following fauna was found
at this level:

Cyathophyllum sp., small.

Cyathophyllum sp., septa with dentate edges.

Calostylis sp.

Halysites labyrinthicus (Goldfuss)

Syringopora sp., form similar to that found in Cedarville dolomite
Lichenalia (?) sp., frequently twisted into more or less tubular
growths as in Cedarville dolomite
Caryocrinus sp.

Atrypa reticularis niagarensis Nettelroth

Camarotoechia neglecta (Hall), with relative^ sharp plications
Clorinda ventricosa (Hall)

Dalmanella springfieldensis Foerste
Leptaena rhomboidalis (Wilckens)

Meristina maria (Hall)

Orthis fissiplicata Foerste
Pentamerus oblongus Sowerby

Platystrophia daytonensis Foerste, with 2 plications in sinus
Platystropliia sp., with 4 plications in sinus, found also in Cedar-
ville dolomite at Springfield, Ohio
Rhipidomella hybrida (Sowerby)

.Schuchertella subplana (Conrad), resembling Rochester shale form
in its elongate outline

Spirifer radiatus (Sowerby), with a few lateral plications
Strophonella sp., resembling Strophonella roemeri Foerste in being
strongly convex and prolonged medially
Strophonella williamsi Kindle and Breger

Cyclonema ohioensis (Hall and Whitfield), described originally as
a variety of Pleurotomaria pauper
Phanerotrema occidens (Hall)

Trochonema sp., large, but with relatively low spire
Calymene celebra Raymond

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

45

In the Euphemia dolomite, beneath the Springfield dolomite
in the Jackson quarry, the following fossils were found:

Enterolasma caliciilum
Favosites sp.

Caryocrinus sp.

Dimerocrinus sp.

Lichenalia sp. with pseudo-tubular growth, as in Cedarville
dolomite

Atrypa reticularis
Brachyprion cf. newsomensis
Camarotoechia neglecta
Leptaena rhomboidalis
Orthis flabellites
Pentamerus oblongus
Platystrophia daytonensis
Rhipidomella hybrida
Schuchertella subplana
Spirifer radiatus
Stropheodonta cf. profunda
Strophonella williamsi
Whitfieldella sp.

Diaphorostoma cf. niagarense
Dalmanites cf. limulurus
Illaenus ioxus

In the Euphemia dolomite, in the large quarry northwest of
Lewisburg, the following species occur:

Enterolasma caliculum

Atrypa reticularis

Leptaena rhomboidalis

Orthis flabellites

Plectambonites transversalis

Schuchertella subplana

Strophonella sp., strongly convex form

Whitfieldella sp., large

Diaphorostoma cf. niagarense

Dalmanites cf. limulurus

Illaenus ioxus

46

AUG. F. FOERSTE

At Ludlow Falls the Euphemia dolomite contains:

Striatopora sp., large form, one-third inch in diameter

Atrypa reticularis

Brachyprion cf. newsomensis

Orthis fiabellites

Pentameriis oblongus

Platystrophia daytonensis

Rhipidomella hybrida

Pentamerus ohlongus is fairly common in the Euphemia dolo-
mite in some of its exposures southwest of Springfield, south of
the railroad passing Cold Springs.

The Cedarville, Springfield, and Euphemia dolomites are
regarded as belonging to a single formation, characterized by
the fact that at a certain horizon, known, as the Springfield
dolomite, the rock is separable readily into flagging, suitable for
building purposes, while the Euphemia dolomite below and the
Cedarville dolomite above are not suitable for flagging. The
term Durbin formation is used for this formation as a whole.

At the Reinheimer quarry, south of New Paris, the so-called
Laurel limestone contains Pisocrinus gemmiformis, and Stephano-
crinus osgoodensis. The same species occur in the abandoned
James Carl quarrj^, miles southwest of Lewisburg, up a small
stream west of the road to Eaton. They occur at a number
of other localities in Preble county, Ohio. In Indiana both
species occur in the Osgood limestone, but Pisocrinus gemmiformis
is cited also from the lower part of the Laurel limestone. At
the quarry west of Drexel Park, f of a mile east of the Union
road, north of the Eaton pike, Pisocrinus gemmiformis occurs
in coarse-grained rock immediately beneath the Springfield
limestone, assumed to be of Euphemia age. Immediately above
the argillaceous strata which form the base of the exposed sec-
tion along the creek a mile east of Leesburg, and north of the
railroad, Stephanocrinus gemmiformis and Stephanocrinus ham-
melli were found in strata apparently belonging to the Bisher
formation. Small species of Pisocrinus and Stephanocrinus,
difficult to discriminate except in the presence of good speci-

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

47

mens, have a considerable vertical range in the Niagaran, and
the specimens found so far at different localities and horizons in
Ohio are regarded as inadequate for purposes of exact correlation.
For the present, therefore, the so-called Laurel limestone of
western Ohio must be regarded as identified lithologically, rather
than paleontologically with the typical Laurel of Indiana.

The same statement can be made regarding the so-called Os-
good clay shale of Ohio. This has been identified lithologically
with a clay shale band well exposed in the upper part of the
quarries southwest of Laurel, Indiana, but the fauna found in
these so-called Osgood clay shales in Ohio is that of the under-
lying Dayton limestone, and not that of the typical Osgood
formation in Ripley and Jefferson counties, in Indiana.

In the large quarry northwest of Lewisburg, Ohio, the top of
the Dayton limestone contains the species usuall3^ identified as
Enter olasma caliculum (Hall), Atrypa reticularis Linnaeus,
Spirifer radiatus (Sower by) , and a Spirifer intermediate between
between niagarensis (Conrad) and eudora (Hall) in the number
of its radiating plications. The middle part of the Dayton
limestone here contains Enterolasma caliculum, Orthis flahellites
Foerste, Plectamhonites transversalis, Spirifer plicatellus Lin-
naeus, Schuchertella subplana (Conrad), and a small species of
Whitfieldella, similar to the one most common in the Osgood and
Laurel limestones of Indiana.

At Rocky Point, 3 miles northeast of Eaton, on the road to
Lewisburg, the Osgood clay, overlying the Dayton limestone
is 4 feet 3 inches thick, and contains the following species: En-
terolasma caliculum, Atrypa reticularis, Leptaena rhomboidalis,
Orthis flabellites, Schuchertella subplana, and the same species
of Spirifer as that cited from the top of the Dayton limestone
at the quarry northwest of Lewisburg.

From Trotwood 2^ miles southward and d miles east, the
following fossils are found in the Dayton limestone: Enterolasm'i
caliculum, Rhinopora sp., Clathrodictyon vesiculosum, Camaro-
toechia neglecta, Leptaena rhomboidalis, Orthis flabellites, Platy-
strophia daytonensis, Platystrophia reversata, and Rhipidomella
hybrida.

48

AUG. F. FOERSTE

At the abandoned quarry north of the Germantown pike,
near the southeast corner of the Soldiers Home, west of Dayton,
the following fossils are found in the Dayton limestone: Entero-
lasma caliculum, Favosites niagarensis, CUdochirus ulrichi,
Chasmatopora angulata, Rhinopora verrucosa, Coelospira sp.,
Leptaena rhomhoidalis , Orthis flahelUtes, Platystrophia reversata,
and Rhipidomella hyhrida.

In the quarries southeast of Dayton, and thence south and
eastward, brachiopoda are scarce in the Dayton limestone, with
the exception of Pentamerus oblongus, which is rare until the
southern margin of Clinton county is reached, but which be-
comes common in parts of Highland and Adams counties, and
reaches even the northern part of Lewis county, in Kentucky.
In the eastern half of Montgomery count}^, and in Aliami,
Clarke, and Greene counties little is seen in the Dayton lime-
stone in addition to Favosites favosus, Favosites niagarensis,
and various species of Orthoceras, not determined.

Beginning at Centerville, and increasing in numbers at Todd
Fork, north of Wilmington, additional species of corals, simple
and compound, appear, reaching their maximum in Highland and
Adams counties, where more than 20 species are known. The
range of these corals continues into the northern part of Lewis
county.

This change of fauna from a brachiopod fauna in western Ohio
to a coral fauna southeastward along the line of outcrop, is the
most significant feature noted so far in the distribution of the
faunas of the Dayton limestone.

In Indiana, the limestone layer underlying the typical Osgood
formation of that state, usually only one or two feet thick, is
correlated with the Dayton limestone of Ohio, but the Indiana
limestone layer is practically unfossiliferous, and the few species
found have not belonged to diagnostic forms, so that they do
not serve for purposes of accurate correlation.

In fact, all of the Ohio Niagaran strata present difficulties
when the attempt is made to correlate them accurately with the
Niagaran strata of Indiana.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

49

While the Dayton, Osgood, and Laurel strata of Montgomery,
Miami, Darke, and Preble counties bear considerable resemblance
to the corresponding sections in the area immediately southwest
of Laurel in Indiana, the so-called Osgood of Ohio does not carry
the typical Osgood fauna of Ripley and Jefferson counties in
Indiana, and the so-called Laurel of Ohio does not carry the-
Laurel fauna so well known in the St. Paul and Waldron areas of
Decatur and Shelby counties of Indiana.

No equivalent to the Euphemia and Springfield strata is
known at present in Indiana. The Cedar ville dolomite of Ohio
carries a fauna much nearer that of the Racine of Wisconsin
and northern Illinois than that of the Louisville limestone of
southern Indiana and northern Kentuck^L The upper Niagaran
strata of the eastern counties of Indiana carry faunas much
nearer that of the Wabash area of northern Indiana than that
of the Cedarville of Ohio, or the Louisville of the southern part
of Indiana. Finally, the upper Laurel fauna of St. Paul has
its affinities rather in the Racine faunas of Wisconsin and north-
ern Illinois than in anything known in Ohio.

In other words, the evidence is accumulating that the Silurian
strata of Ohio, Indiana, and Kentucky present a much greater
complex of faunas than would be supposed by the simple alterna-
tion of limestone and clay zones in the various areas. While
those unacquainted with the faunas will readily match limestones
and clays of one area v/ith limestones and clays of another area,
notwithstanding great differences in faunal content, the paleon-
tologist is not so ready to follow this procedure. In our present
state of knowledge of the Niagaran faunas, most of our correla-
tions are worth very little, and must be considered merely
tentative. There is a great lack of knowledge of the content
and geographical range of the various faunas. Until this lack
is supplied by accurate information, substantial progress is
impossible. Detailed paleontological work on Silurian strata
in Ohio, Indiana, and Kentucky has practically ceased, and
until serious study again is undertaken no vital progress can
be expected.

50

AUG. F. FOERSTE

B. THE FAUNA OF THE WHIRLPOOL SANDSTONE OF ONTARIO

Very little is known of the fauna of the Whirlpool sandstone,
the lowest member of the Medinan in southern Ontario. In
1919 Dr. M. Y. Williams^ listed only the following species from
this sandstone:

Gasteropoda

Pleiirotomaria sp. Niagara River
Hormotoma subulata (Conrad) ?? Glen William
Vermes (burrows and trails)

? Cornulites

From the Grimsby sandstone, in the upper part of the Medinan,
he listed:

Brachiopoda

Lingula cuneata Conrad
Lingula clintoni Vanuxem
Dalmanella eugeniensis Williams
Camarotoechia (Stegerhynchus) neglecta Hall
Pelecypoda

Pterinea cf. undata (Hall)

Pterinea brisa Hall
Modiolopsis primigenia (Conrad)

Modiolopsis orthonota (Conrad)

Modiolopsis kelsoensis Williams
Ctenodonta machaeriformis (Hall)

Nuculites cf. ferrugineum Foerste
Gasteropoda

Bucanella trilobata (Conrad)

From the overlying Thorold sandstone, at the top of the Medi-
nan, he listed:

Worm burrows

Daedalus archimedes (Ringueberg)

Arthrophycus alleghaniensis (Harlan)

® Williams, M. Y., The Silurian Geology and Faunas of Ontario Peninsula and
Manitoulin and Adjacent Islands: Memoir 111, Geol. Surv. Canada, p. 28, 1919.

I

MEDINAN, NIAGAEAN, AND CHESTEK FOSSILS

51

To the brief list of fossils from the Whirlpool sandstone pub-
lished by Dr. Williams we here add a few obtained in the quarry
a quarter of a mile west of the railroad station at Credit Forks,
in southern Ontario. This quarry is located immediately
north of a deep ravine crossing the railroad south of the station.
The fossils were found in thin sandstone layers at the top of the
Whirlpool sandstone, immediately under the basal layers of
Manitoulin dolomite, in which specimens of Leveilleites were
found. Several of these additional species from the Whirlpool
sandstone evidently are merely earlier occurrences of forms
already known from the Grimsby sandstone, in the upper part
of the Medinan.

While some of these specimens are not sufficiently well pre-
served to serve as types of new species, they clearl}^ indicate the
presence in the Whirlpool sandstone of a much larger fauna than
suspected formerly.

The list of species from the Whirlpool sandstone at Credit
Forks is as follows:

1. Lingula cf. cuneata Conrad

2. Dalmanella eugeniensis Williams

3. Schuchertella creditensis Sp. nov.

4. Whitfieldella circularis Sp. nov.

5. Modiolopsis orthonota creditensis Var. nov.

6. Ctenodonta (?) sp.

7. Ctenodonta (?) creditensis Sp. nov.

8. Ctenodonta (?) cataractensis Sp. nov.

9. Liospira (?) sp.

1. Lingula cf. cuneata Conrad
Plate XIII, fig. 9

Lingula cuneata Conrad, 3d Ann. Rep. Geol. Surv. New York,
1839, pp. 63, 64; Hall, Pal. New York, 2, 1852, p. 8, pi. 4, fig. 2e.

Specimen 10 mm. long, 6.5 mm. wide, ovate in outline, and
pointed toward the beak; with a convexity slightly exceeding 1
mm. The general outline agrees more closely with that of figure
2e on the plate in the Paleontology of New York, cited above.

52

AUG. F. ■ FOERSTE

than with the more triangularly cuneate specimens represented
by figures 2a, 2b, and 2c on the same plate.

2. Dalmanella eugeniensis Williams

Plate XIII, fig, 7

Dalmanella eugeniensis Williams, Geol. Surv. Canada,
Memoir 111, 1919, p. 118, pi. VII, figs. 1-8.

Specimen a brachial valve, 7.5 mm. long, and 9 mm. wide;
most strongly convex about 1.5 mm. from the beak, with a
narrow median depression posteriorly, widening to a broad
depression along the anterior half of the valve. About 8 radiat-
ing striae reach the anterior margin of the valve in a width of 3
mm., the total number on the valve being between 40 and 45.

3. Schuchertelia creditensis Sp. nov.

Plate XIII, fig. 6

Cf. Leptaena subplana Hall, Pal. New York, 2, 1852, p. 259,
pi. 53, figs. 8a, 8b.

Pedicel valve 15.5 mm. long, 18.5 mm. wide, with a convexity
of almost 2 mm. at a point 5 mm. anterior to the beak. The
valve is gently convex, without any trace of reversal of curva-
ture anteriorly. At the posterior margin of the valve the lateral
sides curve gently inward. Along the anterior margin, 7 to 8
radiating striae occur in a width of 3 mm., the alternate striae
being distinctly more prominent. Along the postero-lateral
margins this alternation of size is even more evident. The
dental lamellae are nearly 3.5 mm. in length and diverge from
each other at an angle of about 80 degrees.

The largest specimen found was 21 mm. in width.

Several small brachial valves, regarded as belonging to the
same species, are much less convex than the pedicel valve here
described.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

53

4. Whitfieldella circular is Sp. nov.

Plate XIII, figs.X A, B

Cf. Atrypa oblata Hall, Pal. New York, 2, 1852, p. 9, pi. 4,
figs. 4 a, b, c, and 5. Cf. Whitfieldella cataractensis Williams,
Geol. Surv. Canada, Memoir 111, 1919, p. 121, pi. 7, figs. 16,
17, 18.

One brachial valve (fig. 8 A) is 11.3 mm. long, 10.5 mm. wide,
and 3 mm. deep. It is quite evenly convex, except at the margins
where it curves more rapidly. Concentric lines are seen near
these margins. A median septum in the interior of the valve
extended about 3 mm. from the beak.

A second brachial valve (fig. 8 B) is 9.3 mm. long, 9.2 mm.
wide, and 2.3 mm. deep. The median septum on its interior is
2.5 mm. long.

These valves do not appear to be the young of Whitfieldella
oblata (Hall), from the Upper Aledinan of Lockport, New York.
The first of the two specimens here described appears quite
mature, judging from its convexity along its margins. Nor is
it identical with Whitfieldella cataractensis Williams.

5. Modiolopsis orthonota creditensis Var. nov

Plate XIII, figs. 1, 2 A-G

Modiolopsis orthonota. Pal. New York, 2, 1852, p. 10, pi. 4
(bis), figs. 1 a-c.

Numerous valves, of which the largest is 21.5 mm. long, 10.6
mm. high, and 2.5 mm. deep. Specimens 16 to 18 mm. long
are much more common. The cardinal and ventral margins
tend to converge posteriorly. In one specimen 18 mm. long,
the height of the specimen at the beak is 9 mm., while 10 mm.
posterior to the beak it is 8 mm. in height. This appearance of
convergence posteriorly is due in part to the rise of the umbonal
part of the valves above the hinge-line. The posterior part of
the ventral margin rises convexly as far as the posterior termina-
tion of the umbonal ridge, and from this point the posterior
margin of the valve curves strongly forward at an angle of about

54

AUG. F. FOERSTE

120 degrees with the cardinal margin. Along this part of its
outline the posterior margin ^usually is only moderately convex,
there being a distinct tendency toward straightening. The an-
terior part of the valve extends from 3.5 to 4 mm. in front of the
beak. It is fairly evenly convex, its maximum convexity appear-
ing slightly below mid-height of the valve, on account of the
slight inward curvature of this outline on approaching the um-
bonal part of the valve. The umbonal part is relatively broad,
and only slightly elevated above the cardinal margin. The um-
bonal ridge is sigmoidal in direction, starting near the beak at a
small angle with the cardinal margin, this angle increasing to 20
and 25 degrees near mid-length of the valve, and then decreas-
ing again posteriorly as far as the posterior angle of the valve.
The post-umbonal slopes of the valves are distinctly concave,
but the umbonal ridge tends to be rounded, rather than angular.
In most specimens the middle part of the valves, beneath and
anterior to the umbonal ridge, is gently convex antero-poste-
riorly, with a tendency toward flattening where the mesial sulcus
might appear, this sulcus usually being absent, though faintly
indicated occasionally.

Remarks. — These specimens from the Whirlpool sandstone
at Credit Forks, Ontario, differ from typical Modiolopsis ortho-
nota from the Grimsby sandstone at Lockport, and Medina, New
York, in the greater angulation of the posterior side of the um-
bonal ridge and in the more distinctly concave curvature of the
post-umbonal slope, between the umbonal ridge and the hinge-
area.

Owing to its more angular umbonal ridge, the specimen
represented by figure 1 on plate XIII may be designated as
Modiolopsis orthonota perumbonata Var. nov.

In the type specimens of Modiolopsis orthonota that part of
the shell which corresponds to the angular part of the umbonal
ridge of the Credit Forks specimens is more evenly rounded
while the distinctly concave part is narrower, its lower margin
deviating only 2.5 mm. from the hinge-line at the posterior end
of the shell. Immediately beneath the beak of the right valve
the hinge-area appears to have been slightly elevated in a more or

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

55

less vertical direction, while a corresponding elevation occurred
immediately in front of the beak of the left valve. The elevations
may be regarded as incipient teeth. (Plate XIV, figs. 7 A, B.)

The fauna described by Hall from strata 50 to 60 feet below
the top of the sandstone at Medina includes Lingula cuneata,
Modiolopsis orthonota, Modiolopsis primigenia, Pleurotomaria
pervetusta and Bucanica trilohita. This appears to be a Grimsby
sandstone fauna. Modiolopsis primiqenia is represented by fig.
8 on plate XIV.

6. Ctenodonta (?) sp.

Plate XIII, fig. 5

A single left valve, 6.6 mm. long, 4 mm. high, and 1.3 mm.
deep, resembling Modiolopsis orthonota in outline, but without
any trace of concave curvature along a distinctly defined post-
umbonal slope. In fact, there is no distinctly defined post-
umbonal slope, the valve rounding from the general convexity
of its middle parts into a more increased convexity along the
posterior cardinal margin of the shell without any interruption
whatever. In specimens of Modiolopsis orthonota of the same
size the post-umbonal slope is distinctly defined and is distinctly
concave.

7. Ctenodonta (?) creditensis Sp. nov.

Plate XIII, fig. 8

Three valves in which the ratio of the height to the length
varies from 71 to 76 per cent are at hand. In the two larger
specimens the posterior part of the outline is defective. One
of the specimens (fig. 3) is 8.5 mm. in height, and its length is
estimated at 11.8 mm. In the other one of the larger specimens
the height is 7.5 mm., and the length is estimated at 10.5 mm.
The third specimen is 4.2 mm. in height and 55. mm. in length.
The larger specimens are 2 mm. in depth. The anterior parts of
these valves are similar to those of Modiolopsis orthonota, but
the beak is more pointed and is directed more distinctly toward
the front, and the upper half of the anterior outline, anterior to

56

AUG. F. FOERSTE

the beak, is more distinctly concave. Posterior to the beak there
is no trace of an umbonal ridge, the convexity of the valves
increasing toward the cardinal margin. The posterior margin
of the valves is similar to that of a relatively short Ctenodonta.

8. Ctenodonta (?) cataractensis Sp. nov.

Plate XIII, fig. 4

Left valve 7.3 mm. long, 5.5 mm. high, and 1.5 mm. deep.
General outline elliptical, with the longer axis in a horizontal
direction, but with the beak sufficiently elevated to add a slight
triangularity to the elliptical outline. The beak is about 3
mm. from the anterior margin. The outline posterior to the beak
is convex as far as the posterior angle of the valve. The outline
anterior to the beak is almost imperceptibly concave. The
ventral outline is evenly convex along the greater part of its
length, this convexity increasing toward the extremities of the
valve, where the outline is most rapidly rounded. The maximum
depth of the valve is about 2 mm. below the beak.

9. Liospira (?) sp.

Plate XIII, fig. 11

Specimen with a maximum transverse diameter of 5 mm.,
consisting of at least two volutions. Evidently only a part of
the shell is preserved, the number of additional volutions in a
mature specimen being unknown. The spire is depressed, very
much as in Liospira micula (Hall), from the Ordovician. The
outer margin is narrowly rounded, also as in Liospira micula,
and not elevated as in Pleurotomaria (?) pervetusta (Conrad), in
which the height of the spire and of the individual volutions is
much greater. With only a single specimen at hand it is im-
possible to determine with confidence either its relationship to,
or its difference fron Pleurotomaria pervetusta. Tt may be the
apical part of the latter species.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

57

Straparollus (?) pervetustus (Conrad)

Plate XIV y fig. 6

Cyclostoma ? pervetusta Conrad, Ann. Rep. New York State
Geol. Surv., 1838, p. 113; ibid., 1839, p. 65.

Pleurotomaria pervetusta Hall, Pal. New York, 2, 1852, p, 12,
pi. 4 (bis), figs. 3 a-d.

Euomphalus pervetustus Hall, Geol. New York, 4, 1843,
p. 48, figs. 1, 2; tab. ill. 2, figs. 1, 2.

Straparollus pervetustus D’Orbigny, Prod, de Pal., 1, 1849,
p. 30 (gen‘. ref.).

Euconia (?) pervetusta Grabau and Shimer, N. A. Index
Fossils, 1, 1909, p. 642, fig. 874.

Shell 9 mm. wide and 7.5 mm. in height, with the spire rising
3 mm. above the last whorl near the aperture. In the specimeu
figured by Hall the width is 8 mm., the height is 6 mm., and the
elevation of the spire above the aperture is about 2.5 mm. The
vertical outline of the spire is rounded, the lowest volution per-
mitting slightly more than half of the preceding volution to be
seen, while toward the apical end less and less of the preceding
volutions remains visible. About five volutions are present.
Viewed from the exterior of the shell, these volutions appear
circular in cross-section, but along vertical sections of the shell
it is seen that later volutions are in contact with earlier volutions
in such a manner that the inner half of the upper outline of the
lower volution comes in contact with the outer half of the lower
outline of the preceding volution along a lunate curve with its
concave side facing upward and inward. Toward the aperture
this lunate line of contact may be 2.5 mm. in width. At the
base of the specimen there is an umbilicus 1 mm. in diameter.
It is not known to what extent the interior of the umbilicus is
lined by a callous deposit, if any be present. No trace of sur-
face markings of any kind have been discovered.

Locality and formation. — At Medina and Lockport, in the
Grimsby sandstone member of the Medinan.

Remarks. — Until traces of a slit-band are discovered in this
species it seems inadvisable to refer it to Pleurotomaria or to

58

AUG. F. FOERSTE

any of the Pleurotomariidae. It does not possess the conical
spire of Euconia. Externally it resembles such forms as Stra-
parollus hippolyta Billings, and Straparollus mopsus Hall, but
its umbilicus is much smaller. While the relationship of this
species to Straparollus must remain in doubt, in the absence of
any knowledge of the surface features, it is not out of place to
refer to the absence of definite knowledge of any structure in-
dicating affinities with the Pleurotomariidae.

C. FOSSILS FROM THE BASE OF THE MANITOULIN LIMESTONE AT
CREDIT FORKS, ONTARIO

For many years it has been customary to refer certain flat
branching structures found in Ordovician and Silurian strata to
the algae. Some of these, in more recent years, have been re-
garded as due to worm borings, worm tracks, and even to the
cutting action of flowing water. Those, however, which con-
sist of thin black films can not be passed over so lightly, and must
be regarded as at least of organic origin.

The black coloring of the latter specimens usually is regarded
as due to plant origin, being derived in a manner analogous to
the derivation of coal from plant material.

Usually this black material, in the plant-like organisms found
in Ordovician and Silurian strata, does not present any structure.

In the summer of 1911, however, the writer found numerous
fragments of plant-like fronds in one of the quarries at Credit
Forks, in southern Ontario, Canada, which under the microscope
presented distinct, though limited evidence of structure. During
the geological congress held in the summer of 1913 the writer
served as guide to a small party of geologists, and on this occasion
Chris Andrew Hartnagel of the Geological Survey of New York
and Dr. E. 0. Ulrich of the United States Geological Survey
found the remarkable specimen here described as the type of
the genus Leveilleites.

At first these frondose specimens were regarded as belonging
to the algae, and an attempt was made to find algal forms with
corresponding outlines. The reticulating fibers forming the
body of the fronds were interpreted as corresponding to the

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

59

filaments or laciniae which traverse the interior of some of the
more fleshy algae.

However, the fibrous structures traversing the interior of algae
possess such a small quantity of carbon that it is difficult to
conceive how they could remain in a fossil form as anything but
the thinnest imaginable traces. In Leveilleites, on the contrary,
they appear like fibers which had not given way to pressure.
In fact, they appear more like fibers of sponges than of fibers
which could have originated from algae.

Moreover, in the frondose fleshy algae it seemed reasonable
to expect occasional traces of organs of reproduction, in the
form of swellings of the fronds or other structures of sufficient
size to warrant their recognition even in fossil form, but nothing
of the kind was discovered among the numerous specimens
examined.

In fact, as more material accumulated, the plant origin of
these frondose organisms found at Credit Forks seemed less
certain, and the possibility of their being of animal origin less
doubtful.

The reference, in preceding lines, to fibers of sponges is not
intended to suggest that Leveilleites may be some early type of
sponge. It is possible that some other form of animal life
with more or less fibrous material within its structure, not yet
clearly recognized, may have existed in Ordovician and Silurian
times.

Since these frondose organisms found at Credit Forks present
more structure than any similar fiat plant-like bodies found here-
to-fore, they are described and figured in much greater detail
than otherwise would prove desirable. In the twelve years
which have elapsed since their discovery, no additional informa-
tion has been added as the result of further study either of old
material, or material accumulated more recentl}^. Therefore,
it does not seem advisable to withhold the publication of these
observations any longer.

To the account of Leveilleites is added a description of Dictyo-
nema scalarif orme creditensis, Foerste found in the same slabs
of rock as Leveilleites. Several species of fossils found in the

60

AUG. F. FOERSTE

Whirlpool sandstone, directly beneath the layers containing the
Leveilleites, have been described already, on preceding pages.

Leveilleites Gen. nov.

Specimens consisting of linear-oblong frond-like expansions
attached to a more or less twisted stipe. Each lateral margin
of these frond-like expansions is formed by a single series of lobes,
the lobes being small, and those belonging to the same expansion
being approximately of the same form and size.

The frond-like expansions are flat and thin. Their median
line, when the specimens are well preserved, is occupied by a
narrowly linear black film within which no structure has been
observed. In some specimens corresponding films occupy the
median part of the lateral lobes. The significance of these
linear black films is unknown. Although they occupy the
position of a rachis, they apparently do not locate a line of
thickening of the frond.

The lateral parts of the frond-like expansions, as far as any
structure has been observed, consist of fibers, more or less irregu-
larly arranged. In most specimens these fibers anastomose
more or less irregularly, but in a few many of the meshes are
approximately of the same size, usually not exceeding 0.25 mm.
in diameter. Where the narrowly linear black film along the
median line of the frond-like expansions is absent, the fibrous
structure characterizing the lateral parts of these expansions is
seen. This adds to the difficulty of finding a reasonable inter-
pretation of the significance of the linear median black films.
In some specimens, the fibers belonging to the lateral parts tend
to radiate more or less on approaching the margins of the lobes.

The entire surface of the frond appears to be covered by a
coat of very fine hair-like fibers. These fibers are seen most
readily along the margins of the lobes, beyond which they pro-
ject outward a distance varying from less than I mm. to fully
1.5 mm. The finer fibers number here from 5 to 7 or 8 in a width
of 0.5 mm.

In some specimens, black dots are seen in addition to the
anastomosing black fibers within the body of the frond-like

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

61

expansions. These black dots tend to occur in rows, about 5
or 6 in a width of 0.5 mm. Possibly these black dots locate
extensions of some of the anastomosing fibers, and served as
supports of very fine hair-like fibers, similar to those seen along
the lateral margins of the fronds. This appears to be confirmed
by some specimens in which some of the hair-like fibers extending
beyond the margins of the lobes can be traced at their proximal
ends to dots located some distance back from these margins,
along the flat faces of the fronds.

Similar hair-like fibers cover the surface of the dichotomously
branching frond-like expansions occurring in the Cayugan of
the Buffalo area of New York, and in the Kokomo formation of
northern Indiana. These Upper Silurian frond-like expansions
usually are referred to Buthotrephis, a genus originally described
from the Chazyan and Trenton of New York.

While it is customary to refer these Upper Silurian forms of
Buthotrephis to the algae, it should be remembered that no
evidence of structure within the frond or of characteristic forms
of reproduction have yet been adduced in proof of this view.

The black coloring of the specimens of Buthotrephis from the
Buffalo and Kokomo areas usually is regarded as evidence of
plant origin, the black coloring being regarded as being derived
from plant material, like coal. However, it is exceedingly doubt-
ful whether such minutel}^ fibrous structures as those here
described in Leveilleites ever could have had a plant origin, con-
sidering the perfection of their preservation.

Under a microscope, the fibers of Leveilleites are seen to pass
between the minute sand grains forming the matrix as though
these fibers had some measure of stiffness at the time of their
burial in the sea mud. Apparently they were more or less free
from other material.

These fibers resemble the fibers of sponges more than those
of plants. However, even if of animal origin, the fronds of
Leveilleites show no trace of oscula or of other characteristic
structures of sponges. Possibly they belong to some group of
animals not yet discriminated from those recognized so far.

02

AUG. F. FOERSTE

Among the living algae most closely resembling the fronds of
Leveilleites in general outline are Leveillea jungermannoides
(Mart. & Her.) Harvey and Polyzonia elegans Suhr. Both belong
to the family Rhodomelaceae of the class Rhodophyceae, or
Red Algae and both occur in the waters off Mauritius. The first
of these species is figured by Engler and Prantl in Die Naticr-
lichen Pflanzenfamilien (I Theil, 2 Abtheilung), on page 463 of
their volume on Algae, a generic description being given on .the
following page. Since the resemblance in general outline is
quite striking, the term Leveilleites is here proposed for the Cana-
dian frond-like expansions here described, without intending to
convey any belief that these Canadian forms are algae.

The genus Caulerpa, belonging to the class Chlorophyceae,
or Green Algae, also presents lobate frondose expansions; this
is true especially of Caulerpa crassifolia (Ag.) J. Ag., shown on
page 136 of Engler and Prantl, but this is a mmch larger form
than Leveilleites.

Among Hepaticae, there are foliose species of Calypogeia
(= Kantia), Lophocolea, Chiloscyphus, etc., but Hepaticae
probably were not in existence in Silurian times; at least they
are not known to have occurred in the Silurian.

The genotype of Leveilleites is Leveilleites hartnageli Foerste.

Leveilleites hartnageli Sp. nov.

Plates IV -XI

Type. — Specimen (plate IV, fig. A) 70 mm. in length, con-
sisting of a stipe over 40 mm. in length, to which 12 or more
frond-like expansions are attached. The frond-like expansions
are about 20 mm. in length and from 3 to 4 mm. in width. The
median line of the expansions is occupied by a narrowly linear
black film, from one-third to two-fifths of a millimeter in width.
In its present state of preservation, the divisions between the
lateral lobes continue almost or quite to the continuous median
black film. The number of lateral lobes of the frond-like ex-
pansions varies from 6 to 8 in a length of 10 mm., 7.5 lobes being
the most frequent number.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

63

This type specimen is associated on the same slab with Dictyo-
nema scalariforme creditensis Foerste, and was found in the basal
part of the Manitoulin dolomite, directly over the Whirlpool
sandstone, the two lower members of the Medinan formation in
southern Ontario. It was found in the quarry a quarter of a
mile west of Credit Forks station, on the northern side of the
deep valley which crosses the railroad south of the station. Here
the Whirlpool sandstone forms the base of the quarry, and
Leveilleites occurs in fair abundance in the basal layers of the
Manitoulin dolomite, which here is quarried extensively.

Associated with Leveilleites in other slabs from the same lo-
cality and horizon are Leptaena rhomhoidalis Wilckens and a
species of coral resembling Enterolasma facetus Foerste in size
and form. The Leptaena is 23 mm. in width. The coral is 25
mm. in length, measured along its convex side, and 15 mm. in
diameter at the top. It is curved at the base very much as in
figure 5, plate V, of Dr. M. Y. Williams’ memoir.^o These
fossils indicate the marine character of the deposits containing
Leveilleites.

The type of Leveilleites hartnageli belongs to the collection of
C. A. Flartnagel, a member of the Geological Survey of New
York. The reverse of the same specimen belongs to the collec-
tion of Dr. E. O. Ulrich, of the United States National Museum.

The species is named in honor of Air. Hartnagel, one of the
original collectors.

Similar specimens. — Among the numerous separate fronds of
Leveilleites found at the type locality and horizon, those repre-
sented by figures 4, 5, 6, 11, and 12 on plate V are similar in
presenting 6 to 8 strongly divided lobes in a length of 10 mm.;
figure 26 on plate IV is the reverse of figure 5 on plate V. Speci-
men 5 is represented also on plates VII and X, and specimen 26
is represented also on plate VII.

In specimen 4 the lobes are convexly curved on the side ex-
posed to view, and they evidently are continuous laterally, the

1'’ Williams, M. Y., The Silurian Geology and Faunas of Ontario Peninsula and
Manitoulin and Adjacent Islands: Geol. Surv. Canada, Memoir 111, 1919.

64

AUG. F. FOERSTE

appearance of separation being due chiefl}^ to the presence of
matrix along the depressed parts of the frond.

Of specimen 5 both the obverse and reverse are present. The
lobes are distinctly separated, and incline so that the upper mar-
gin of each lobe is at a higher level than the lower margin of the
next lobe, when the frond is held horizontally. Hair-like fibers
extending from the margins of the lobes for a distance of 1 mm.
are numerous, and some of these are directed distinctly at an
angle with the plane of the lobes. Apparently these hair-like
fibers were attached in part to the flat faces of the lobes. Six
occur in a width of 0.5 mm. Reticulation among the fibers
forming the lobes is present. Series of minute dots may be
recognized among the* reticulating fibers. These served as
points of attachment for the hair-like fibers.

Specimen 6 presents a median, rachis-like film 0.4 mm. wide.
The lobes slope, as in the preceding specimen. The hair-like
fibers attached to the flat surface of the fronds are clearly shown,
and several of these are replaced by rows of distinct black dots,
7 or 8 in a length of 0.5 mm., interpreted as denticulations on
the lateral margins of these fibers. Viewed from the side, the
reticulating fibers forming the fronds present approximately
circular, rather than flattened cross-sections.

Specimen 11 shows a tendency toward distinct lobes. Both
reticulated and hair-like fibers are present. In addition there
are several rows of black dots. Some of the hair-like fibers
appear to arise from these dots and to extend beyond the margin
of the frond.

Specimen 12 presents similar rows of black dots, both among
the reticulated and among the hair-like fibers. Among the
latter the dots are distinctly smaller. Of the larger black dots
in the frond 6 occur in 1 mm.; on the hair-like fibers 5 to 7 dots
occur in 0.5 mm. Some of the hair-like fibers are 1.5 mm. long.

Specimens with more numerous lobes. — In the specimens
represented by figure 3 on plate V and figure 20 on plate VI, more
numerous lobes occur, than in the specimens described so far.
The first of these specimens exposes several fronds with 9 or 10
lobes in a length of 10 mm.; the second has 11 lobes in the same
length.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

65

Specimen 3 is represented by both the obverse and reverse
parts. In specimen B the lateral margins of the lobes appear
confluescent. In several small fragments between A and B
the lobes are conspicuously separated from one another; possibly
only the median parts of these lobes are preserved. In B,
the rachis-like median film is 0.5 mm. wide. The reticulating
fibers appear to radiate more or less toward the margin of the
lobes. Numerous hair-like fibers, 1 mm. in length, extend
beyond the margin of the frond. Among the reticulating and
hair-like fibers there are rows of black dots, those among the hair-
like fibers being smaller.

In specimen 20, the left margin of the frond is distinctly lobed,
while the right margin is only crenulated. Apparently the
marginal parts of the lobes are not well preserved on the dis-
tinctly lobed side. Rows of black dots appear both among the
reticulated and among the hair-like fibers.

Appearance of lobation sometimes deceptive.— Some speci-
mens which on macroscopical examination appear strongly
lobed, on microscopical examination appear less indented, the
lateral parts of the supposed lobes being confluescent, the loba-
tion being confined to marginal crenulations. Specimens of
this type are represented by figures 1, 7 A, 8, 9, and 10 on plate
V, and b}^ figures 18 B and 21 on plate XI. Additional figures
of specimens 8, 18 B, and 21 are found on plates VIII, XI, and
IX respectively.

Frond A on specimen 1 presents very well the median black
rachis-like film. Rows of black dots are very distinct, varying
from 6 to 9 in 1 mm.

Specimen 8 shows very well the median rachis-like film of the
frond, 0.4 mm. wide. The fibers within the frond form relatively
coarse and irregular meshes. Along the central part of the frond,
black dots occur in series, 5 or 6 in 0.5 mm. The hair-like fibers
extend 1 mm. beyond the margin of the frond. Black dots
along these hair-like fibers number 6 or 7 in 1 mm. The hair-like
fibers probably were attached both to the margin of the frond
and to its flat faces.

66

AUG. F. FOERSTE

Specimen 10 shows very well the reticulation among the fibers
forming the body of the frond. The hair-like fibers extending
beyond the margin of the frond are also well preserved. Speci-
men 18 B exposes very well some of the hair-like fibers near the
lateral margin of the frond. The appearance of lobation is due
to oblique wrinkling. Frond B on specimen 18 is one of the best
specimens to suggest the presence of reticulations among the
fibers of the frond. Near the median line of the frond 3 meshes
occur in a length of 1 mm. ; at a greater distance from the median
line they are more irregularly arranged. Of the larger black
dots, 5 occur in a length of 1 mm. Specimen 21 shows along its
right margin several of the series of black dots regarded as
locating the direction of some of the hair-like fibers.

In specimen 23 the right hand frond is seen under the micro-
scope to be crenulated rather than lobed, the appearance of
lobation being due in part to a twisting of the frond near the
inner angles of the points of indentation. The median rachis-
like film is poorly preserved, but may be traced readily. Retic-
ulation among the fibers of the frond is evident. The hair-like
fibers extend more than 1 mm. beyond the margin of the frond,
and some of them may be traced to points of attachment on its
flat surface.

In specimen 22 the rachis-like film of the median part of the
frond is 0.6 mm. wide, the corresponding parts of the lateral
lobes being 0.25 mm. wide. The reticulated fibers produce
meshes from 0.2 mm. to | mm. long. Along some of the hair-
like fibers there are 6 or 7 dots in a length of 0.5 mm.

In specimen 24 the main rachis is 0.6 mm. wide, while the
corresponding parts of the lateral lobes are 0.4 mm. wide. The
latter are so well preserved that on macroscopical examination
the frond appears lobed, while microscopically the frond is seen
to be merely crenulated.

Specimens with crenulated margins. — Specimens with the
lateral margins of the frond-like expansions crenulated rather
than lobed are so common that eventually they may be regarded
as more normal than the lobed specimens of Leveilleites. Speci-
mens with crenulated edges are represented by figures 2, 3A,

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

67

and 7B on plate V, by figures 13, 14, 15, 16, 17, 18A, 19, and
21A on plate VI, and by figure 25 on plate IV. Additional
figures of 3 A, 21 A, and 25 are presented on plates VII and IX.

In specimen 2 the median rachis-like film is 0.4 mm. in width.
Among the reticulating fibers several series of black dots num-
ber 6 or 8 in a length of 0.5 mm. Hair-like fibers extending
beyond the margin of the frond are well shown.

Specimen 3A shows traces of the median rachis-like film.
Some of the meshes enclosed by the reticulated fibers are about
0.2 mm. in dmmeter. Distinct black dots near the median part
of the frond number 5 in 0.5 mm. Some of the hair-like fibers
present similar series of dots of smaller size, regarded as denticu-
lations on the sides of these fibers. The larger dots within the
flat area of the frond may have served as points of attachment
of some of the hair-like fibers.

The frond in the lower right-hand corner of specimen 7 has a
rachis-like film 0.5 mm. wide. The black dots belonging to the
reticulating fibers number 5 in 0.5 mm. Those belonging to the
hair-like fibers number 7 in the same distance.

In specimen 13 the main rachis-like film is 0.7 mm. wide, the
corresponding parts of the lateral lobes are 0.4 mm. in width. The
specimen 14 has a main rachis-like film 0.4 mm. wide, the lateral
median films being 0.3 mm. in width. The frond apparently
was about 0.1 mm. thick. Seven black dots occur in a length
of 0.5 mm. on the. surface of the frond, but these dots are as fine
as those belonging to the hair-like fibers.' In specimen 15 the
width of the rachis-like film is 0.5 mm. In specimen 16 its width
is also about 0.5 mm. The corresponding lateral films are 0.3
mm. wide. Black dots tend to occur locally in diagonally
intersecting series. Between 6 and 7 dots occur in a length of 1
mm., apparently serving as points of attachment for the hair-
like fibers. In specimen 17 the main rachis-like film is from 0.7
to 0.8 mm. wide; the corresponding lateral structures are 0.4
mm. wide. Near the margin of the frond 4 to 5 black dots occur
in a length of 0.5 mm.

In specimen 18A the rachis-like film is 0.3 mm. wide. The
substance of the frond evidently consists of something more than

68

AUG. F. FOERSTE

a thin carbonaceous film, the reticulating fibers being distributed
through a visible thickness of the matrix, though possibly scarcely
a 0.1 mm., in this dimension. The reticulation of the fibers of
the frond can be recognized locally. The hair-like fibers extend
2 mm. beyond the margin of the frond. They arise apparently
from black dots on its flat surface.

In specimen 19 the rachis-like film is 0.5 mm. wide. The
reticulated structure of the fibers forming the body of the frond
is visible. From 4 to 6 hair-like fibers occur in a width of 0.5
mm. along the margin of some of the lobes. From 6 to 7 dots
may be recognized in a length of 0.5 mm. along some of these
fibers.

In specimen 21 A the rachis-like film, 0.5 mm. wide, is distinctly
shown, and the series of dots belonging to the fibers along the
margin of some of the lobes are distinctly visible. Of the larger
black dots, 6 or 7 occur in 1 mm.

In specimen 25 the median rachis-like film is 0.4 mm. wide;
the corresponding structures of the lateral lobes are far less
distinctly outlined. The appearance of reticulation among the
fibers forming the frond is strikingly shown. Some of the meshes
are 0.4 mm. long and 0.2 mm. wide. On close examination
many of these fibers appear to be supplied by a series of dots,
varying from 5 to 7 in a length of 0.5 mm. Some of those near
the margin of the frond serve as points of attachment for the
hair-like fibers. At one point numerous hair-like fibers may be
traced for almost 3 mm. beyond the margin of the frond. They
are shown best near B as located on plate 'IX.

Buthotrephis Hall

The genus Buthotrephis was founded by Halb^ on Buthotrephis
tenuis Hall, from the Trenton of New York, and not on Butho-
trephis antiquata Hall, from the Chazyan of that state. This is
evident from his statement in the description of Buthotrephis
antiquata that “In the present genus, the typical form is to be
found on plate 21, fig. 1,’’ where the genotype is erroneously

Hall, James, Paleontology of New York, vol. 1, p. 8, 1847.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

69

portrayed under the name ButhotrepMs gracilis, a name previously
used by Hall in for a Clinton form of New York. In the

second volume of the Paleontology of New York (p. 18) Hall
corrected this error and introduced the name Buthotrephis tenuis
for this genotype.

In describing Buthotrephis tenuis Hall states that carbona-
ceous film is all that remains of the fossil/^ and also that this
fossil is found ^^upon a shaly carbonaceous film on the lime-
stone.”

In his original description of the genus Hall defines the latter
as follows: Stems subcylindric or compressed, branched; branches
numerous, divaricating, leaflike; structure vesicular?

Little appears to be gained by a study of the Trenton type.
In his study of two species from the Kokomo member of the
Cayugan, at Kokomo, Indiana, however. Dr. David White makes
some observations which may prove illuminating in connection
with the structure of the genus Leveilleites. He describes the
fronds of Buthotrephis divaricata White^^ as rugulose or minutely
granulose, and marked, especially along the medial portion,
by very delicate, irregularly, but more or less obliquely, arranged
trichomatose or filamentose impressions. Without a cen trial
axis or strand. Vague globular bodies near or at the apices
of the branches. Similarly he describes the texture of Butho-
trephis newlini White^^ as slightly rugose, marked by irregular,
very slender, intermingled and tangled trichomatose or filamen-
tose elements, those near the center being coarser, often thread-
like, and more or less longitudinal in their arrangement. Simi-
lar filamentose texture occurs in Buthotrephis lesquereuxi Grote
and Pitt, from the Bertie member of the Cayugan at Buffalo,
New York. Here there is an irregularly woven or cloth-like
mesh.

More recently, specimens referable to Buthotrephis lesquereuxi

Hall, James, Geology of New York, part 4 (fourth district), p. 69, fig. 14.

White, David, Two new species of Algae from the upper Silurian of Indiana:
U. S., Nat. Mus., Proc., vol 24, pp. 265-270, pi. 16, 1902. See also Proc. Biol. Soc.
Washington, 15, 1902, p, 86.

Idem. p. 266, pis. 17, 18.

70

AUG. F. FOERSTE

have been studied by Dr. Rudolph Ruedemann/^ and have been
referred by him to the genus Inocaulis. Figure 4 on plate 4 of
his account shows in striking manner the black dots on the sur-
face of the frond, evidently serving as points of support of the
hair-like fibers which evidently cover the entire surface of the
frond, but which are seen best where projecting beyond its
margins. According to Dr. Ruedemann the surface of the frond-
like growth is covered with fine tubercles in some places and
with fine pores in others. The tubercles are the casts of the
pores, so that the entire surface of the organism appears covered
with pores. The pores terminate in fine straight tubes having
the dimensions of fibers, more or less perpendicular to the sur-
face of the frond. Of the circular pores 5 occur in a length of 1
mm. The width of the hair-like tubes is 0.05 mm. The original
form of the branches of the frond is regarded as having been
cylindrical in form. Such fibers as appear within the fronds
appear twisted together irregularly, rather than forming reticu-
lating meshes. The structure is regarded as graptolitic, allied
to Inocaulis, Palaeodictyota, Acanthograptus, and the like. The
possibility of the fibers being chitinous, rather than carbonaceous,
is indicated.

It is evident that Leveilleites presents structures suggestive
of the Kokomo and Buffalo forms formerly referred to Butho-
trephis. There is a possibility of their being of animal, rather
than of vegetable origin. As to their affinities to the Dendro-
graptidae among the Dendroidea order of the graptolites, the
present writer is in no position to express any opinion, not being
sufficiently familiar with the latter.

Buthotrephis creditensis Sp. nov.

Plate XV A, figs. 15 A, B ^

Flat fronds, known only from fragments 65 mm. long and 30
to 35 mm. wide; originally probably similar in size and shape to

Ruedemann, Rudolph, Account of some new little-known species of fossils,
mostly from the Paleozoic rocks of New York: N. Y. State Mus. Bull. 189, 1916,
})p. 13-17, text fig. 4 and pi. 4, figs. 1-4.

MEDINANj NIAGARAN, AND CHESTER FOSSILS

71

the specimen of Phaenopora expansa Hall and Whitfield, illus-
trated in 1893/® excepting that one of the specimens has a more
distinct lobation along one part of its margin. None of the
specimens are dichotomously branched as in the species of
Buthotrephis described from the Bertie member of the Cayugan
in the Buffalo area of New York, or those described from the
Kokomo member of the Cayugan of northern Indiana. Although
to the unaided eye these fronds appear flat and continuous,
under the microscope the frond appears to possess a structure
consisting in part of longitudinal lines connected by cross lines,
producing oblong or oval meshes, the whole somewhat resembling
a Dictyonema. Of the more or less branching longitudinal lines
there usually are from 7 to 8 in a width of 5 mm. Of the oblong
or oval meshes there are about 5 or 6 in a length of 5 mm. It
is impossible to determine from the material in hand how the
walls of these meshes are constructed. Apparently they are
built up of fibers, more or less reticulating, so as to produce
' narrow walls more or less vertical to the plane of the fronds, at
least along that part of the walls which lies nearest the surface
of the frond. The inner part of the frond appears to consist
of a continuous sheet of black material, although it is possible
that here the fibers are merely more closely interlaced. It is
impossible to determine whether the oblong or oval meshes occur
only on one side or on both sides of the frond. If they locate
anything corresponding to zooecia, it has been impossible to
verify this fact.

Locality and formation.^ — ^Associated in the same fragments
with Leveilleites in the basal members of the Manitoulin dolomite,
at Credit Forks, Ontario.

Dictyonema scalariforme creditensis Var. nov.

Plate IV, fig. B

Dictyonema scalariforme Foerste, Bull. Sci. Lab. Denison
Univ., 2, pt. I, 1887, p. 108, pi. 8, figs. 28, 29; Geol. Surv. Ohio,
Pal. 7, 1893, p. 600, pi. 27, figs. 28, 29.

Foerste, A. F., Fossils of the Clinton group in Ohio and Indiana: Ohio Geol.
Surv., vol. 7, pi. 29, 1893.

72

AUG. F. FOERSTE

Rhabdosome originally infundibuliform, with sides diverging
at angles varying in different specimens from 45° to 75°. The
base of this rhabdosome tends to be pointed. Its length usually
is from 25 to 30 mm. Between 12 and 15 branches occupy a
width of 10 mm. The branches vary from 0.3 to almost 0.5
mm. in width, and tend to be narrower than the spaces between
them. Usually the branches are almost straight. They are
connected by dissepiments forming large angles (usually nearly
right angles) with the branches. Seven or 8 of these dissepi-
ments occur in a length of 5 mm. Along the greater part of their
length these dissepiments are only slightly larger than 0.05
mm., but they enlarge near contact with the branches. The
resulting meshes are quadrangular. The apertures of the thecae
are not distinctly preserved in any specimen at hand but in
several specimens the worn surfaces show rounded or elliptical
outlines which are regarded as locating the thecae. Of these
there are about 9 in a length of 5 mm., the number decreasing in
some specimens to 8 in this distance.

I.ocality and formation. — In the quarr^^ north of the deep
ravine at Credit Forks, Ontario, a quarter of a mile west of the
railroad station. In the basal part of the Manitoulin dolomite,
a member of the Medinan.

Remarks. — In the original description of Dictyonema scalari-
forme the number of thecae was given as 13 in a length of 5 mm.
Since in the Credit Forks specimens only 9 were noticed in the
<=?ame distance there is a possibility that a distinct form here is
represented, for which the name Dictyonema scalariforme credi-
tensis is proposed.

D. A LOWER MEDINAN FAUNA BELOW THE BRASSFIELD LIMESTONE

IN OHIO

In the quarry half a mile northeast of Centerville, Ohio, and
about ^ of a mile northwest of the railroad station, the full section
of the Brassfield limestone and of the Dayton limestone is ex-
posed. At one point the Dayton limestone is overlain by the
lower part of the argillaceous layers formerly known as the
Niagara shale, and at present doubtfully referred to the Alger

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

73

shale. Beneath the Brassfield limestone there are about 4 feet
of argillaceous material weathering into a gritty clay. The latter
has recently been traversed by ditches, and numerous gastero-
poda, of strongly Ordovician aspect, have been exposed. In
addition there is a species of Ctenodonta and of one Spyroceras,
both of which have Ordovician affinities. The brachiopoda,
on the contrary, are distinctly Silurian in character, and the
same is true of one fragment of a pygidium of Dalmanites. The
list includes the following:

1. Schuchertella siibplana brevior Var. nov.

2. Brachy prion

jj- Whitfieldella cf. ovoides Savage

4. Bellerophon centervillensis Sp. nov.

5. Hormotoma trilineata Sp. nov.

6. Hormotoma centervillensis Sp. nov.

7. Liospira (?) depressum Sp. nov.

8. Lophospira ehlersi Sp. nov.

9. Lophospira (Ruedemannia ?) centervillensis Sp. nov.

10. Loxoceras husseyi Sp. nov.

11. Spyroceras microtextile Sp. nov.

12. Ctenodonta cf. simiilatrix Ulrich

13. Dalmanites

The specimens are not found in situ but occur intimately
mixed together in the material thrown out from the ditch, and
this material occurs in the original low ridges formed at the time
these ditches were dug. Any effort to discover any other source
is futile.

Since the Edgewood limestone in southern Illinois and eastern
Missouri occurs below the Brassfield limestone of those states,
the fauna of the Edgewood limestone, as described and figured by
Savage^^ was searched for possible similar species, but with
no definite success. Such genera as Schuchertella, Brachy prion,
Whitfieldella, Bellerophon, Hormotoma, Liospira, Lophospira,
Ctenodonta, and Dalmanites are represented in the Edgewood
limestone, and although none of the species from the Center-

Savage, T. E., Stratigraphy and paleontology of the Alexandrian series in
Illinois and Missouri: Illinois State Geol. Surv. Bull. 23, 1913.

74

AUG. F. FOERSTE

ville quarry can be proved identical with those found in the
Edgewood limestone, the affinity of these specimens from the
lower argillaceous strata in the Centerville quarry appears to
be nearer those of the Edgewood formation than those of any
other formation so far described. Additional material is needed
to confirm such a correlation.

Back of a house on the west side of the road following Beasley
fork southward from West Union, Ohio, there is an exposure of
Belfast rock, beneath the typical Brassfield. The upper layer,
1 foot thick, is the typical Belfast. Below this is more shaly
rock, containing Enter olasma caUculum. About 4 feet beneath
the typical Belfast there is a thin argillaceous rock layer con-
taining the Rhynchonelloid here identified as Rhynchotreta the-
besensis Foerste, and a form resembling Hormotoma trilineata,
Foerste, but smaller in size. Prof. W. H. Shideler, who was the
first to recognize the Silurian age of these strata, found also a
small form of Whitfieldella at this horizon.

Rhynchotrema thebesensis was found by Prof. Shideler also on
the E. P. Smalley farm, about 2 miles south of Lawshe, in Adams
county, where a small stream flows into Brush creek from the
east. Here the Belfast bed is feet thick.

At the Whippoorwill chapel, miles northeast of West
Union, the typical massive Belfast bed contains Platystrophia
daytonensis Foerste and several annulated specimens of Ortho-
ceroids, possibly Dawsonoceras. In the overlying thin-bedded
argillaceous strata the same species occur as are found in the
immediately overlying part of the Brassfield limestone. These
thin-bedded argillaceous strata at the base of the Brassfield
limestone, and carrying a Brassfield fauna, are especially com-
mon in the northwestern quarter of Adams county, Ohio, between
Winchester, Graces Run, Seamon, and northward.

These argillaceous strata carrying the Brassfield fauna,
whether these strata be thin-bedded or thicker-bedded, are dis-
tinct from the lower argillaceous strata carrying the fauna listed
from the base of the Centerville quarry, the Beasley Fork
locality, and the locality 2 miles south of Lawshe, on the E.
P. Smalley farm. The former are clearly of Brassfield age. The

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

75

latter appear to belong to a distinctly lower horizon, possibly
corresponding to the Edgewood of western Illinois and eastern
Missouri.

Schuchertella subplana brevior Var. nov.

Plate XIV, fig. 13

Width of shell at hinge-line 29 mm.; length 18 mm. Pedicel
valve with a maximum convexity of 1.5 mm. at a distance of 3
mm. from the hinge-line, flattening out toward both the lateral
and anterior margins. Radiating striae alternating in size;
about 8 of the more prominent striae occupy a width of 5 mm.
along the anterior margin of shell. Brachial valve more evenly
convex, with the maximum convexity at about two-fifths of
the length of the shell from the hinge-line.

Locality and formation.^ — Quarry | mile northeast of Center-
ville, Ohio; in the argillaceous strata immediately beneath the
Brassfield limestone.

Remarks. — In typical Schuchertella subplana (Conrad) the
ratio of the length to the breadth usually varies from 75 to 90
per cent, while the form here described has a ratio of only 62 per
cent.i^

The Waldron form, also known under the name Schuchertella
subplana, is as short as the Centerville form, but the radiating
striae are coarser. It may be known as Schuchertella subplana
waldronensis Var. nov.

Brachyprion sp.

Plate XIV, fig. 12

Shell 25 mm. in width, enlarging to 30 mm. along the hinge-
line, owing to the acute extension of the postero-lateral angles.
Length 21.5 mm. Only the interior of a valve is at hand
and this is assumed to be the pedicel valve. The hinge-
area is 1 mm. in height at the beak. On the inner surface of
this valve a strong median striation extends from a short dis-
tance anterior to the beak forward to a point about half-way

Hall, James, Paleontology of New York: vol. 2, 1852, pi. 53.

76

AUG. F. FOERSTE

between the beak and the anterior margin of the shell. Judging
from the concavity of the inner side of this valve, the maximum
convexity of its exterior was about 9 mm. from the hinge-area,
and it equalled about 3 mm. From this point the convexity
continued quite evenly as far as the lateral and anterior margins
of the valve. The radiating striae on the outer surface of the
shell were very fine and even, and numbered about 10 to 12 in
a width of 3 mm.

Locality and formation.' — Quarry J a mile northeast of Cen-
terville, Ohio; in the argillaceous strata immediately beneath
the Brassfield limestone.

Remarks.' — Br achy prion stropheodontoides Savage is figured
and described as rather strongly convex in the median portion
of the ventral valve, and as most strongly convex in its umbonal
region. There is no corresponding accentuation of the convexity
of this valve in its median parts in the Centerville species here
described.

Whitfieldella cf. ovoides Savage
Plate XIV, fig. 14

Whitfieldella ovoides Savage, Bull. Geol. Surv. Illinois, 23,
1913, p. 90, pi. 5, figs. 13-15; pi. 7, fig. 13.

Shell 16.5 mm. long, about 14 mm. wide, and estimated to
have been about 10 mm. thick. The pedicel valve is considerably
deeper than the brachial valve, and arches strongly over the
latter at its beak. The shell tends to be broadest at its postero-
lateral margins, about 7 mm. anterior to the beak of the pedicel
valve. Anteriorly the lateral outlines converge. The anterior
margin is rounded. The median part of the pedicel valve is
grooved rather narrowly. Casts of the interior of the pedicel
valve are fairly common, and exhibit casts of the cavity beneath
the beak enclosed by the convergent dental lamellae, and
casts of the impressions left by the diductor scars. The latter
are striated or ridged longitudinally. The surface of both valves
is rather strongly marked in a concentric manner by striae
or ridges indicating successive stages of growth. Possibly these

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

77

are not so strongly marked on other specimens as on the single
one at hand which shows the surface features.

Locality and formation.^ — Quarry J mile northeast of Center-
ville, Ohio; in the argillaceous strata immediately beneath the
Brassfield limestone.

Remarks.^ — These Centerville specimens bear some resemblance
to Whitfieldella ovoides Savage, from the Edgewood limestone of
Illinois and Missouri and the Channahon limestone of Illinois.
Better specimens are needed to make strict comparison possible.

A similar form, 13 mm. in length, was found by Professor W.
H. Shideler about 4 feet below the base of the typical Belfast
bed exposed 2 miles south of West Union, on the Beasley Fork
road, in strata containing Hormotoma sp., and Rhynchotreta
thebesensis.

Rhynchotreta thebesensis Foerste
Plate XIV, fig. 15

Rhynchotreta thebesensis Foerste, Bull. Sci. Lab. Denison
Univ., 14, 1909, p. 94, pi. 4, figs. 66 A-C; Savage, Bull. Geol.
Surv. Illinois, 23, 1913, p. 80, pi. 4, figs. 19-20.

Valve, regarded as brachial, 16 mm. long, 16 mm. wide, with
a convexity of 4 mm. Ornamented by 10 coarse, radiating
plications which at the anterior margin of the shell are strongly
angular and 1 mm. in height. In the absence of the pedicel
valve, and without any knowledge as to the structure of the
inner surface of the valve at hand, it is impossible to determine
with confidence the generic relations of this valve; but, in its
size and general appearance, it resembles the shell described from
the Edgewood formation of southern Illinois, and eastern
Missouri, under the name Rhynchotreta thebesensis.

Locality and formation.^ — Found by Professor W. H. Shideler
on the E. P. Smalley farm, 2 miles south of Lawshe, on a small
creek flowing into Brush creek from the east. A similar speci-
men was found by him also two miles south of West Union,
along the Beasley Fork road, beneath a typical exposure of Bel-
fast rock about 4 feet. The Belfast bed here is 1 foot thick.

78

AUG. F. FOERSTE

Bellerophon c enter villensis Sp. nov.

Plate XIV, fig. 20

Shell attaining a diameter of 20 mm. in a direction across the
umbilicus; but most specimens vary between 12 and 15 mm. No
specimen retaining the entire width of the shell at its flaring
aperture is at hand, but from such fragments as are preserved it
is estimated that this aperture is at least as wide as the diameter
of the shell across its umbilicus. The general cross-section of
the last volution is almost evenly convex, with only a faint
tendency toward angularity toward the slit-band. The slit-
band varies in width from about 0.4 mm. in specimens of average
size to 0.6 mm. in a few of the larger specimens. The slit-band
is borne on the crest of a median carina whose elevation usually
is barely \ mm. above the general convexity of the shell, and
never exceeds 0.5 mm. The lateral walls of this carina usually
rise rather abruptly. The umbilicus is small, but distinct,
varying in size between that shown by Bellerophon troosti and
its variety hurginensisl^ Along the side of the shell, the re-
flexed lateral margin of the posterior part of the aperture termi-
nates against the posterior wall of the umbilicus, and there is no
evidence of a strong posterior reflexion of the posterior or inner
lip of the aperture along the median part of the shell It is
possible, therefore, to see the carina and the transverse surface
striae along that part of the last volution which usually, in species
of Bellerophon, is covered by the reflexed inner lip of this aperture.
The surface of the shell is covered by very fine transverse striae,
strongly reflexed both laterally and toward the carina, very much
as in Bellerophon recur vus Ulrich.

Locality and formation.^ — Quarry | mile northeast of Center-
ville, Ohio, in the argillaceous strata immediately beneath the'^
Brassfield limestone.

Remarks.^ — Bellerophon centervillensis has a decidedly Ordovi-
cian aspect. From Bellerophon consimilis Savage it differs in

Ulrich, E. O., and Scofield, W. H., The Lower Silurian Gastropoda of Minne-
sota; Minn. Geol. and Nat. Hist. Surv., Pal., vol. 3, 1897, pi. 64. figs. 1, 4, 6.

Idem., pi. 64, figs. 12, 13.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

79

being distinctly less angular along the median part of the shell,
resulting in a less triangular cross-section. Unfortunately the
surface striae of the Edge wood species are unknown.

Hormotoma trilineata Sp. nov.

Plate XU, Fig. 6

Spire attaining a length of 32 mm., and a width of 14 mm.;
apical angle usually between 28° and 33°. The number of
volutions usually is 10 or 11. The sutures form an angle of
about 75° with the vertical axis of the shell. The slit-band is
peripheral in position; its width varies from 0.6 to 1 mm. The
upper margin of the slit-band tends to be at mid-height of the
volution and to form its most prominent part, while the lower
margin of this band lies along the lower slope of the volution,
slightly closer to the axial part of the shell. The general form
of the volutions varies considerably in different specimens.
Usually there is a tendency toward angularity, the margins of
the slit-band being elevated slightly above the general convexity
of the volutions, sometimes with a faint concave curvature of
the shell both immediately above and below the band. In some
specimens the concave curvature immediately above the band
is quite distinct and broad. In that case there may be a faint
revolving angulation about 1.5 mm. above the slit-band. Above
this angulation there may be a slight flattening of the general
convexity of the volutions. At the sutures the surface curves
abruptly inward. On the lower slope of the last volution, at a
distance of 2.5 mm. from the slit-band, there may be a second
faint angulation, usually stronger than the one described first.
In by far the greater number of specimens the general convexity
of the volutions tends to be angulated on approaching the slit-
band, and the upper half of the volutions tends to be slightly
conical in slope.

Along the upper part of the shell the slit-band usually is
trilineate, two very narrow sharp lines forming the lateral borders,
and a broader line occupying the median line, or a position slightly
above the median line of the band. The trilineate character

80

AUG. F. FOERSTE

of the band can be detected where the diameter of the shell is
only 1.5 mm. On the last one or two volutions the median
line frequently becomes obsolete, and the area of the slit-band is
relatively flat. Not infrequently the slit-band is strongly
convex across its entire width, the bordering striae are obsolete
or have weathered away, and the general resemblance of the
shell is similar to that of Lophospira producta Ulrich or Lopho-
spira howdeni (Safford). In most of these cases the resemblance
is striking only along the last 3 or 4 volutions, and the earlier
volutions show the trilineate character of the slit-band with
varying degrees of distinctness.

The course of the transverse striae is the same as that indicated
by Ulrich^i in his figures of Hormotoma. The lunulae traversing
the slit-band transversely are well shown. The apertures, as
far as preserved, are similar.

Locality and Formation.' — Found in the large stone quarry
half a mile northeast of Centerville Ohio, in the argillaceous
strata immediately underlying the Brassfield limestone.

Remarks.' — The relationship of this species appears to be
with Hormotoma gracilis Hall and Hormotoma suhangulata Ulrich
and Scofield, rather than with Hormotoma salteri Ulrich. At
any rate, the surface of the volutions does not curve concavely
upward on approaching the sutures above them.

More than a thousand specimens were examined. This
accounts for the numerous variations, some of which have been
noted above. Some variations are represented only by a few
specimens. For instance, in some cases the angulations above
and below^ the slit-band are very distinct, and there may be
even a second angulation present above this band. Individuals
with an apical angle of 37° to 40°, and with only 8 or 9 volutions,
also are relatively rare, but more than 20 specimens were noted.
(Plate XV, fig. 4.)

In one specimen with an apical angle of 35 degrees, 9.8 mm.
wide at the base, 8 volutions are present, and 2 or 3 belong to the
apical part, which is missing. The volutions in this case appear

Idem., pi. 70.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

81

low and crowded, resembling those of Coelocaulus oehlerti Ulrich^^
in their crowded conditions, but the spire is much shorter.
(Plate XV, fig. 5.)

In a few specimens the slit-band is traversed by 3 revolving
striae or lines of elevation, the two lateral ones lying closer to
the median striation than to the striae forming the lateral mar-
gins of this band.

A similar form, but only 6 mm. in length and with 5 or 6
volutions, was found by Professor W. H. Shideler of Miami
University at the exposure of the Belfast bed 2 miles south of
West Union, on the Beasley Fork road. The typical Belfast
bed here is 1 foot thick, and the specimens of Hormotoma are
common about 4 feet beneath.

No Silurian species of Hormotoma with such a strongly Ordovi-
cian facies as that presented by the specimens here described
are known. Loxonema suhulata Conrad may be a Hormotoma,
but it presents an aspect quite different from that of the Center-
ville specimens.

Hormotoma centervillensis Sp. nov.

Plate XV, fig. 7

Spire with an apical angle of about 20° and with sutures form-
ing an angle of about 70° with the vertical axis of the shell. The
base of the shell attains a maximum diameter of 11 mm. Five
volutions occur in a length of 26.5 mm., and it is estimated that
the 'original length of the shell equalled about 36 mm., and that
within this length there were 10 or 11 volutions.

Compared with Hormotoma trilineata the volutions are more
oblique and more elongate. No tendency toward angulation
of the volutions along its periphery, where the slit-band is lo-
cated, is noticed. The surface here is evenly convex. The mar-
gins of the slit-band are indicated by relatively faint, and very
narrow lines. The area of the band itself is flat, and shows no
evidence of trilineation.

-2 Idem., pi. 70, figs. 61, 62.

82

AUG. F. FOERSTE

In one specimen the surface of the shell curves upward on
approaching the suture above, somewhat as in Hormotoma sal-
teri canadensis Ulrich, but in the remainder this feature is
not noted.

This form ma}^ eventually prove to be only one of the many
variants of Hormotoma trilineata, but at present it appears suffi-
ciently distinct to warrant a different name.

Locality and horizon.^ — Quarry | mile northeast of Center-
ville, Ohio; in the argillaceous beds immediately beneath the
Brassfield formation.

Remarks.- — Compared with Hormotoma suhulata (Conrad)
the volutions of this species are relatively shorter. It is similar
in size and in the number of volutions to Hormotoma tenera
Savage, but the surface features of the latter are not known,
so that exact comparison is impossible.

Liospira (?) depressum Sp. nov.

Plate X/F, jig. 16

Shells attaining a height of 5.5 mm. and a maximum diameter
of 13 mm. Spire very depressed. Omitting the last half of
the last volution, the height of the apical part of the spire over
the remainder of the shell equals slightly more than 0.5 mm.;
above the aperture it rises about 2 mm., most of this elevation
being due to the downward curvature of the last half of the last
volution. There are 4 volutions, enlarging to a width of slightly
more than 4 mm. at the aperture of a shell 5.5 mm. in diameter.
Toward the apical end the cross-sections of the volutions are
more nearly circular, but along the last volution the depression
of the shell becomes increasingly obvious, and at the same time
there is a moderate obliquity of the upper surface of this volu-
tion, especially toward the aperture. The umbilicus is about
2 mm. in diameter. Along the last half of the last volution this
umbilicus is bordered by a callous deposit along the inner margin
of this part of the volution. This deposit varies from 1 to 1.2

23 Idem., pi. 70, fig. 48.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS 83

mm. in width, has a thickness of about 0.5 ^mm., is distinctly
outlined along its convexly curved margin, and presents a steep
slope on its concavely curved side, facing the umbilicus. No
trace of surface markings is visible. Therefore it is impossible
to determine the generic relations of this species. The fact that
the callous deposit is strongly margined along its exterior border
suggests that this shell may be genericall}^ distinct from Liospira.

Locality and formation.^ — Quarry ^ mile northeast of Center-
ville, Ohio, in the argillaceous strata immediately beneath the
Brassfield limestone. Possibly a Pycnomphalus.

Lophospira ehlersi Sp. nov.

Plate XIV fig. 17

Shell 17.5 mm. in height, with a maximum width of 15.5
mm., and an apical angle of about 80°. At the aperture the last
volution has an elevation of 10 mm. There are 5 or 6 volutions,
the apical one rarely being preserved distinctly. General
outline simdar to that of Lophospira peracuta Ulrich and Scofield^^
but with a much lower spire, somewhat as in Lophospira tropi-
dophora Meek. The upper volutions expose only their upper
slopes and the peripheral angle, but the second last volution
exposes an increasing amount of its lower slope, so that near the
aperture fully 2 mm. intervene between the peripheral angle of
the second last volution and the suture beneath. The peripheral
angle is more or less acute, the degree of acuteness usually being
greater along the last volution. The slit-band is located on
the peripheral angle. At the aperture its width is about 1 mm.
or slightly more. Its upper and lower margins are defined
distinctly by very fine, sharp lines. The entire width of the
band is raised into an angular ridge, whose upper and lower
faces form an angle of about 60°. The upper face of the slit-
band slopes at about the same angle as the upper face of the
volution, and the lower face of the band slopes at an angle simi-
lar to that of the lower face of the volution, the crest of the
ridge formed by the band being directed upward and outward.

Idem., pi. 73.

84

AUG. F. FOERSTE

Near the band the -upper surface of the last volution is concavel}^
curved, and a similar concave curve marks the lower surface
of this volution, at a distance of 2 mm. from the crest of the
Carina formed by the band. In general, the lower surface of
this last volution has an outline similar to that of Lophospira
peracuta, and the transverse striae follow a similar course, both
above and below the band. A narrow umbilical opening is left
between the inner lip of the aperture and the remainder of the
last volution.

liOcality and formation.^ — Quarry | mile northeast of Center-
ville, Ohio, in the argillaceous strata immediately beneath the
Brassfield limestone.

Remarks. — Lophospira ehlersi has a distinctly Ordovician
aspect. Compared with Lophospira thehesensis the spire is
taller, and the peripheral angle is much more acute.

Named in honor of Prof. George M. Ehlers, one of the geolo-
gists active in collecting the gasteropoda of the lower strata in
the Centerville quarry.

Lophospira (Ruedemannia?) centervillensis Sp. nov.

Plate XIV, fig. 18

Shell 1.2 mm. in height, 11 mm. in maximum width, with the
last volution occupying- a height of 7 mm. near its aperture.
The apical angle is about 87°, There are 6 volutions, of which
the apical one scarcely ever is distinctly preserved. The slit-
band is located at the angular peripheral margin, about 0.75
nun. beneath the level of the suture limiting the last volution.
Above this band the surface of the volution rises only moderately
toward the suture, while immediately below the band the outline
of the volution is either vertical or curves slightly outward before
curving inward toward the umbilical parts of the shell. In
general the outline of this shell is similar to that of Lophospira
sumnerensis (Salford), but with the peripheral angle located
farther up on the volutions, the angulation of the spire resembling
that of Lophospira trochonemoides Ulrich, but without any angu-
lation along the lower part of the last volution, where the surface
curves toward the umbilicus.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

85

Near the aperture the width of the upper flattened surface of
the last volution is nearly 4 mm. Approximately half-way
between the peripheral angle and the suture there is a prominent
revolving rib, the area between this rib and the peripheral angle
being distinctly concave. A similar concave area, 2 mm. in
height, extends from the peripheral angle downward. Beneath
this area there is a series of revolving ridges of which the upper 5
are distinct and occupy a total height of 2.3 mm. Beneath this
level 4 or 5 much fainter revolving lines are seen, occupying
about the same space measured along the vertical curvature of
volution.

The slit-band is 0.7 mm. wide near the aperture; it is bordered
by very fine, sharp lines, and its entire width is raised so as to
form an angle of about 90° along the median line, the apex of
this angle being rounded.

Along the flattened slope above the peripheral angle the trans-
verse striae are very fine and curve strongly back toward the
slit-band. Below the peripheral angle the transverse striae are
nearly vertical, except within the groove immediately below
this angle, where the striae curve distinctly back toward the
slit-band.

A narrow umbilical opening remains between the inner margin
of the aperture and the remainder of the lower face of the last
volution.

Locality and formation.' — From the argillaceous layers im-
mediately below the Brassfield limestone at the quarry half a
mile northeast of Centerville, Ohio.

Remarks. — This species is regarded as closely related to
Lophospira inexpectans (Hall and Whitfield), but the striation
of the latter is much finer and more abundant in a revolving
direction.

Poleumita bellasculptilis Savage has an angular carina separat-
ing the upper slope of the volutions from their middle and basal
portions. Along the last volution this upper slope is nearly
flat and is marked by 3 revolving ridges of which only the middle
one persists in the two uppermost volutions. Below the carina
there are 12 to 15 revolving ridges. The upper volutions grad-

86

AUG. F. FOERSTE

ually become more rounded, the more apical volutions being
nearly circular in cross-section. There is some resemblance here
between the mature form of Poleumita hellasculptilis and Lopho-
spira centervillensis , but since their early stages are entirely
different, according to the description presented by Salvage, it is
not likely that they are related generically.

Loxoceras husseyi Sp. nov.

Plate XV, figs. 3 A-D

Conch in its present condition more or less ellipitical in cross-
section; 15 mm. wide laterally and 11 mm. in diameter dorso-
ventrally at the larger end of one fragment of a phragmacone.
At the smaller end of this fragment, 30 mm. distant, the corre-
sponding diameters are 9.5 and 8.5 mm. Originally the cross-
section probably was circular, or nearly so. Apical angle usually
about 10°, equalling 12° or 13° in several specimens. Nine
camerae occur in this length of 30 mm. At the smaller end of
the specimen there are about 3 camerae in a length equal to the
lateral diameter at the top of the series being counted. Farther
up this number changes to 3.7 camerae in a corresponding length.

The sutures of the septa are directly transverse. The con-
cavity of the septa is not well shown except at the smaller ends
of specimens, but it is estimated to have been about 4 or 5 mm.
where the diameter is 12 to 15 mm. Location of siphuncle
central, or nearly so. Segments of siphuncle oblong-elliptical,
or slightly narrower below so as to be slightly fusiform in out-
line; 2.5 to 3 mm. wide in specimens in which these segments
are 3.5 mm. in length. Septal necks short, from 0.25 to | mm.
in length.

Surface smooth. In a considerable number of specimens in-
distinguishable in any other respect from the smooth forms, the
surface of the shell is covered by numerous very fine vertical
striae varying from 7 to 13 in number in various individuals.
Provisionally these striae are regarded as due to the structure
of the interior of the shell, the striae appearing after a certain
amount of weathering has taken place.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

87

Locality and formation.^ — Quarry half a mile northeast of
Centerville, Ohio, in the argillaceous strata immediately beneath
the Brassfield limestone.

Nam.ed in honor of Dr. R. C. Hussey of Michigan University.

Spyroceras microtextile Sp. nov.

Plate XV, fig. 2

Fragments of phragmacones 8 to 9 mm. in diameter, very
slowly enlarging. At present elliptical in cross-section, formerly
probably circular, or nearly so. Distinctly annulated, 5 annula-
tions occurring in a length equal to the diameter of the conch at
the point where the annulations are counted. In a specimen in
which the total length of one of the annulations together with
that of the groove above is 2 mm., the annulation occupies a
length of almost 0.8 mm., the groove being 1.2 mm. in length.
The surface of the shell is ornamented by very fine vertical and
transverse lines, of which the former are detected more readily.
Of the vertical striae there are 12 in a width of 1 mm.; of the
transverse striae there are about 10 to 12 in a length of 1 mm.,
their number varying apparently more than in the case of the
vertical striae.

Locality and formation.' — Quarry | mile northeast of Center-
ville, Ohio, in the argillaceous strata immediately beneath the
Brassfield limestone.

Remarks. — Judging from the description of Orthoceras textile
Hall, the Centerville species is closely similar in ornamentation,
but the annulations are relatively more numerous. Unfor-
tunately, the type of Orthoceras textile is lost, so that it is im-
possible to make closer comparisons.

Ctenodonta cf. simulatrix Ulrich
Plate XIV, fig. 19

Complete shells about 8 mm. in length, with outlines similar
to those of Ctenodonta simulatrix Ulrich, from the upper part
of the Richmond near Spring Valley, Minnesota. However,
nothing is known of its hinge teeth.

88

AUG. F. FOERSTE

Locality and Formation. Quarry half a mile northeast of
Centerville, Ohio; in argillaceous strata immediately beneath
the Brassfield limestone.

Dalmanites sp.

Plate XIV ^ jig. 10

Fragment of the right side of a pygidium, with 9 pleural ribs,
each traversed lengthwise by a median groove. For a width of
about 1.5 mm. the margin of the pygidium is smooth, and un-
marked by pleural ribs. The pygidium probably was 20 mm. in
length, exclusive of any posterior spine, if a spine was present.

Locality and formation.' — Quarry f mile northeast of Center-
ville, Ohio; in argillaceous strata immediately beneath the Brass-
field limestone.

Remarks. — This Centerville fragment differs from Dalmanites
danai in having the anterior part of the pleural lobes of the py-
gidium more directly transverse, and the pleural ribs less strongly
curved backward at mid-length of the pygidium. Moreover, the
marginal part is relatively broad, flat, and free from markings
by the terminations of the pleural ribs.

E. THE BRACHIOPODA OF THE BRASSFIELD LIMESTONE OF OHIO

The following is a revision of the list of brachiopoda found in
the Brassfield limestone published in 1893.^^

Crania diibia Foerste
Crania clintonensis (Foerste)

Fleet ambonites transversalis (Wahlenberg)

Plectambonites prolongatus (Foerste)

Leptaena rliomboidalis Wilckens
Leptaena centervillensis Foerste. Sp. nov.

Strophonella hanoverensis (Foerste)

Strophonella daytonensis Foerste
Schuchertella daytonensis Foerste Sp. nov.

Orthis euorthis Foerste ( = militaris Foerste)

25 Foerste, A. F., Fossils of the Clinton group in Ohio and Indiana: Ohio Geol.
Surv., vol. 7, 1893, p. 597.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

89

Orth is dinorthis Foerste
Orthis fissiplicata Foerste
Hebertella fausta (Foerste)

Hebertella fausta squamosa (Foerste)

Hebertella daytonensis (Foerste)

Platystrophia daytonensis (Foerste)

Platystrophia reversata (Foerste)

Dalmanella parva (Foerste)

Dalmanella cf. eugeniensis Williams
Rhipidomella h3^brida (Sowerby)

Triplecia ortoni Meek
Platymerella manniensis Foerste
Whitfieldella cf. cataractensis Williams
Atrypa cf. marginalis (Dalman)

Atrypa marginalis multistriata Foerste
Atrypa laticorrugata Foerste

Camarotoechia (Stegerhynchus) scobina (Meek) »

Camarotoechia convexa (Foerste)

Parastrophia sparsiplicata (Foerste)

Stricklandinia triplesiana Foerste

Leptaena center villensis Sp. nov.

Plate XIV, fig. 11

Pedicel valve 30 mm. long, 28 mm. wide at mid-length, 33 mm.
wide along the hinge-line, the postero-lateral angles being acute.
Valve moderately convex for a distance of 25 mm. anterior to
the beak, and then rapidly descending toward the anterior margin
for a nearly vertical distance of 15 mm. The more moderately
convex part of the valve is concentrically wrinkled as far for-
ward as 23 mm. anterior to the beak. The number of the wrin-
kles varies from 11 to 16 in different specimens. The wrinkles
are of approximately equal size anteriorly, becoming smaller
and less elevated toward the beak. About 18 mm. anterior
to the beak some specimens have a rather faint tendency toward
a concentric downward curvature of the shell. The radiating
striae are numerous, approximately of the same size, and number
about 18 in a width of 5 mm. along the anterior slope of the shell.

90

AUG. F. FOERSTE

The muscular scar in the interior of the pedicel valve is about
15 mm. long and 12 mm. broad. Its postero-lateral margins
diverge at an angle of 80°. Along the anterior half of the scar
the lateral margins are approximately parallel or converge but
moderately. The lateral thirds of the anterior margin are dis-
tinctly limited, but the median third is at the level of the general
surface of the interior of the valve. The lateral margins rise for
a height of 0.5 mm. The adductor scars extend 12 mm. anterior
to the beak, the antero-lateral parts of the muscular area extend-
ing 3 mm. farther. The total space between the valves of the
complete shell at its geniculation is scarcely 5 mm.

Locality and formation.^ — Quarry ^ mile northeast of Center-
ville, Ohio; in the upper part of the Brassfield limestone. Com-
mon.

Remarks.- — Forms similar to those of typical Leptaena rhom-
hoidalis are not uncommon in Brassfield strata, but the form
here described is much larger, more elongate, and less abruptly
geniculate anteriorly. The body of the pedicel valve is more
convex, and the anterior wrinkle is not abruptly limited pos-
teriorly.

Strophonella hanoverensis (Foerste)

Strophomena hanoverensis Foerste, Proc. Boston Soc. Nat.
Hist., 24, 1890, p. 301, pi. 6, fig. 1.

Strophomena (Orthothetes) hanoverensis Foerste, Geol. Surv.
Ohio, 7, 1895, p. 567, pi. 27, fig. 34; pi. 31, fig. 1.

In the original description of this species it is stated that the
ventral valve is convex, but that the part near the beak is
flattened or even contains a very slight median depression of
very short length. This depression is indicated by the upper
part of the outline accompanying the figure of this supposed
ventral valve. This outline is repeated in volume 7 of the Geo-
logical survey of Ohio, cited above. It is evident from this
description and figure that the supposed ventral valve is in
reality the brachial valve, and that the species is a true Stro-
phonella.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

91

Strophonella daytonensis Foerste

Strophomena paten ta Hall and Whitfield, Geol. Surv. Ohio,
Pal. 2, 1875, p. 115, pi. 5, fig. 10.

Strophonella daytonensis Foerste, Amer. Jour. Sci., 4th ser.,
18, 1904, p. 339.

The form figured by Hall and Whitfield is the type of Stro-
phonella daytonesis. It is not uncommon in the Brassfield lime-
stone of Ohio, and occurs also in Indiana and Kentucky. Figs.
35, 36, and 37 on plate 8 of volume 2, of the Bulletin Sci. Lab.
Denison Univ., 1887, and of plate 27 of volume 7 of the Geology
of Ohio, 1895, may represent young individuals of this species.

Schuchertella daytonensis Sp. nov.

Streptorhynchus tenuis Foerste, Bull. Sci. Lab. Denison Univ.,
2, 1887, p. 105, pi. 8, figs. 31, 32, 38.

Strophomena (Orthothetes) tenuis Foerste, Geol. Surv. Ohio,
7, 1895, p. 568, pi. 27, figs. 31, 32, 38.

Compared with typical tenuis (Hall), from the Waldron of
Indiana, daytonensis is narrower and has radiating striae more
nearly equal in size. Figure 32 on the plates cited above is the
type.

Orthis euorthis Foerste

Orthis calligramma var. euorthis Foerste, Geol. Surv. Ohio,
7, 1895, p. 572, pi. 25, figs. 12 a, b.

The name euorthis appears in the description of the plate
cited above, and figure 12 on this plate represents the type of
the species.

Orthis dinorthis Foerste

Orthis calligramma var. dinorthis Foerste, Geol. Surv. Ohio,
7, 1895, p. 572, pi. 31, figs. 4, 5.

The name dinorthis appears in the description of the plate
cited above, and figures 4 and 5 on this plate represent the
types of the species.

92

AUG. F. FOERSTE

Orthis fissiplicata Foerste

Orthis calligramma fissiplicata Foerste, Geol. Surv. Ohio,
7, 1895, p. 573, pi. 37a, figs. 20, a, b.

This species is cited by Savage from the oolite member of the
Edgewood limestone in eastern Missouri and western Illinois.

Platymerella manniensis Foerste

Platymerella manniensis Foerste, Bull. Sci. Lab. Denison
Univ., 14, 1909, p. 70, pi. 1, fig. lA-D.

Pentamerella? manniensis Savage, Bull. 23, Geol. Surv. Illi-
nois, Stratigraphy and Paleontology of the Alexandrian Series
in Illinois and Missouri, pp. 28-36 of reprint.

Platymerella manniensis Foerste, Bull. Denison Univ., 19,
1920, p. 223, pi. 23, figs. 5 A-H.

This species has been found at the base of the Brassfield lime-
stone in the quarry immediately north of Lawshe, in Adams
county, Ohio. In the Alexandrian strata of Missouri and
Illinois it occurs immediately beneath those strata which contain
a typical Brassfield fauna. The Brassfield horizon, according
to Savage, cited above, is 34 feet thick, and the underlying
Platymerella manniensis horizon is 1|^ feet thick. Spirifer radia-
tus is found in strata overlying the typical Brassfield.

In Missouri and Illinois, the Platymerella manniensis horizon
is underlain, in descending order, by the Essex, Edgewood, and
Girardeau limestones. The argillaceous strata immediately
beneath the Brassfield limestone in the quarry half a mile north-
east of Centerville, Ohio, appear to belong to equivalents of
either the Essex or Edgewood limestone.

Whitfieldella cf. cataractensis Williams

Meristella umbonata Foerste, Bull. Sci. Lab. Denison Univ.,
1, 1885, p. 88, pi. 13, fig. 2 a, b; Geol. Surv. Ohio, 7, 1895, p.
590, pi. 25, fig. 2 a, b.

The Brassfield specimens described and figured under the
name Meristella umbonata undoubtedly resemble the type of
Athyris umbonata Billings externall}^ Internally they present

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

93

the structure of a Whitfieldella. Under the name Hindella um-
honata Billings Hall and Clarke figure specimens from the same
locality as Athyris umhonata Billings, but representing outlines
closely similar to those of Athyris prinstana Billings, both of
which had been described by Billings from the same locality
and horizon on Anticosti island. Hall and Clarke made these
supposed specimens of Athyris umhonata the type of their new
genus Hindella, However, the Brassfield specimens appear
to be distinct forms of Whitfieldella, so that, if Billing^ s species
Athyris umhonata is identical with the form so recognized by
Hall and Clarke, regarding which there is some possibility of
doubt, then the term Hindella umhonata is not suitable for the
Brassfield form, and the term Whitfieldella umhonata might
prove misleading. Possibly the Brassfield species is closely
related to Whitfieldella cataractensis Williams from the Mani-
toulin dolomite and Cabot Head shale of the Cataract formation
of Ontario.

Parastrophia sparsiplicata (Poerste)

Cyclospira ? sparsiplicata Sp. nov., Geol. Surv. Ohio, 7,
1895, p. 593, pi. 37a, figs. 18 a, b.

The chief feature of this shell is the presence of a median fold
on the more strongly convex valve, the one whose beak overtops
that of the other valve. This median fold bears two plications
anteriorly, and an additional plication is faintly indicated on
each side of the fold. No structure of this type exists in the
genotype Cyclospira hisulcata (Emmons). However, in Para-
strophia the brachial valve overtops the pedicel one. There is a
tendency toward the development of a median fold with an
even number of plications on this valve, and lateral plications
occur. Therefore, it is regarded as much more likely that the
Brassfield specimen in question belongs to the genus Parastrophia.

94

AUG. F. FOERSTE

F. THE GASTEROPODA OF THE BRASSFIELD LIMESTONE OF OHIO

The following is a revision of the list of gasteropoda found
in the Brassfield limestone published in 1893.^®

Bellerophon exiguus (Foerste)

Bellerophon opertus Foerste
Bucanella trilobata (Conrad)

Bucania fiscellostriata (Foerste)

Oxy discus youngi (Foerste)

Cryptaulus filitextus (Foerste) Gen. nov.

Lophospira (Ruedemannia ?) inexpectans (Hall and Whitfield)
Liospira affinis (Foerste)

Hormotoma subulata (Conrad)

Cyclonerna daytonense Foerste
Cyclonema gyronemoides Foerste. Sp. nov.

Cyclora alta Foerste
Straparollus incarinatus Foerste
Diaphorostoma daytonense Foerste. Sp. nov.

Subulites directus Foerste
Meekospira planilateralis (Foerste)

On3^chochilus abruptum (Foerste)

Oxy discus youngi (Foerste)

Cyrtolites Youngi Foerste, Proc. Boston Soc. Nat. Hist.,
24, 1889, p. 289, pi. 6, fig. 7; Geol. Surv. Ohio, Pal. 7, 1893, p.
549, pi. 31, figs. 7, 7a.

From the cross-section of the t5^pe of the species it is evident
that the last volution enveloped the carina of the preceding
volution with a heart-shaped base, as in typical Oxydiscus, the
conch being narrow and the carina very acute.

Cryptaulus Gen. Nov.

Spire low, the successive volutions rising high up on the sides
of the immediately preceding volutions, and covering the slit-
band of the latter entirely. The upper part of each volution

2® Foerste, A. F., Fossils of the Clinton group in Ohio and Indiana: Ohio Geol.
Surv., vol. 7, 1893, p. 596.

MEDIN AN, NIAGARAN, AND • CHESTER FOSSILS 95

is less convex than its sides, thus assisting in the general depressed
appearance of the spire. Along mid-height of the last volution
is a narrow slit-band, bordered on each side by a single striation,
which is distinct, though but slightly raised above the general
surface of the shell. General vertical outline of the volutions
rounded, without revolving ridges, striae, or grooves, excepting
only the groove of the slit-band. All surface striae transverse.
Umbilicus open, as far as known.

Genotype. — Pleurotomaria fiUtexta Foerste.

Cryptaulus filitextus (Foerste)

Pleurotomaria filitexta Foerste, Geol. Surv. Ohio, Pal. VII,
1893, p. 550, pi. 37A, figs. 6a, b.

Shell 10 mm. wide, and scarcely 6 mm. high. Volutions 5,
the spire rising 1.7 mm. above the surface of the last volution.
Slit-band barely 0.4 mm. in width near the aperture. Here 22
transverse striae occur in a width of 2 mm. These striae curve
backward along the upper surface of the last volution so as to
form an angle of about 70 degrees with the slit-band until within
the immediate vicinity of the latter, where the transverse striae
curve more strongly backward. Along the lower side of the
slit-band the transverse striae also curve backward on approach-
ing this band.

Locality and formation.^ — Found at the abandoned Huffman
quarry f mile southeast of the Asylum for the Insane, in the
southeastern part of Dayton, Ohio, in the Brassfield limestone.

Remarks.' — The general appearance of Cryptaulus filitextus
is that of a Helix, but provided with a slit-band at mid-height
of the last volution, the slit-band of earlier volutions being covered
up successively by the later volutions. No other Silurian shell
with exactly the same type of structure is known.

Pleurotomaria aequilatera (Wahlenberg), as figured by Lind-
strom^^ is similar in its general Helix-like form, its open umbilicus,
and the presence of a slit-band at mid-height, or only slightly
above mid-height of the volutions. Figure 27 on the plate cited

Lindstrom, Silurian Gastropoda of Gotland, 1881, pi. 9.

96

AUG. F. FOERSTE

bears the greatest resemblance, but in all cases the slit-band
remains exposed, immediately above the sutures.

Pleurotomaria helicina Lindstrom,^^ is similar in having the
slit-band of earlier volutions covered up by the successively
later volutions, but the slit-band is located slightly above mid-
height of the volutions and there is a revolving callous thickening
along the rim of the umbilicus. The shell is much more de-
pressed. Possibly this species ma^^ prove congeneric with
Cryptaulus fiUtextus.

In the genus Trepospira Ulrich^^ the slit-band also is visible
only on the last volution, but the umbilicus is closed by a callous
deposit. Shells of this type originated apparently as early as
the Hamilton formation, where Pleurotomaria rotalia occurs.
However, the typical forms of this genus are of Carboniferous
age.

Lophospira (Ruedemannia?) inexpectans (Hall and Whitfield)

Pleurotomaria inexpectans Hall and Whitfield, Geol. Sury.
Ohio, Pal. 2, 1875, p. 117, pi. 5, fig. 12.

Height 26.5 mm., greatest lateral diameter 23.5 mm., greatest
height of spire 16.5 mm., apical angle 83°. Slit-band peripheral,
1.5 mm. in width near the aperture, distinctly outlined along its
upper and lower margins by sharply defined revolving striations.
Slit-band strongly convex transversely, its median parts rising
at least ^ mm. above its lateral parts toward the aperture. Here,
where its width is 1.5 mm., the median part of the slit-band is
traversed by three revolving striae, equally spaced, 0.3 mm.
apart. Of these the middle striation is traversed longitudinally
by an extremely narrow groove, which can be detected only
where the preservation of the shell is excellent. Along the
periphery of the second-last volution, the slit-band is acutely
angular instead of convex, and there is only a single revolving
striation, but this is prominent and is located along the median
line of the band.

Lindstrom, Idem., pi. 11.

Ulrich, E. O., and Scofield, W. H., The Lower Silurian Gastropoda of Minne-
sota: Minn. Geol. and Nat. Hist. Surv., Pal. vol. 3, pt. 2, 1897, p. 957.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

97

In the last volution, the vertical outline above the slit-band
is gently concave, the concave curvature being more pronounced
toward the band. Below the slit-band the vertical outline
is convex, with a tendency toward a concave outline within 2
mm. of the band, due chiefly to the prominence of the peripheral
portion of the shell bearing this band. In the second-last volu-
tion, the slope of the shell above the slit-band is interrupted at
mid-height by a very prominent revolving striation, dividing
this slope into two equally concave revolving areas. Along the
last volution this striation becomes less prominent and occupies
a position increasingly farther up the slope, being three-fifths
of the distance from the slit-band to the suture above, near the
aperture. Along this part of the shell the striation in question
is merely slightly more prominent than those above and below,
and does not interrupt conspicuously the general concave out-
line between the slit-band and the suture above. Above this
more prominent striation, the surface of the last volution is
marked by 9 revolving striae. Beneath this more prominent
striation there are 4 striae about as prominent as those above
this striation, and then a fifth striation distinctly more promi-
nent than any of the preceding four is found. The upper half
of the space between the fifth striation and the slit-band is
occupied by 5 much fainter striae, with a sixth faintly visible
a short distance beneath. Along the second-last volution only
4 or 5 revolving striae occupy each of the two concave areas
forming the visible part of this volution between the slit-band
and the suture above.

Immediately below the slit-band, along the concave part of
the shell, toward its aperture, the revolving striae are very faint
toward the band but become increasingly stronger at a greater
distance. At least 40 revolving striae occur between the slit-
band and the umbilical portion of the shell. These tend to be
approximately equal in size, though slight alternation in promi-
nence is noted. In general the prominence of these striae
distinctly exceeds that of most of the striae along the upper
two-thirds of that part of the last volution which is above the
slit-band.

98

AUG. F. FOERSTE

Transverse or vertical striae distinct, sharply defined, and
equidistant. Along the peripheral part of the last volution,
near the aperture, 8 striae occur in a width of 2 mm. Three
millimeters below the slit-band, the number of transverse striae
increases abruptly from 8 to 13 in a width of 2 mm., and this
finer striation continues as far as the umbilicus.

Along the slit-band the transverse striae curve backward so
as to form an angle of 60° with the vertical axis; farther up they
form an angle of 80° with this axis, and farther down their
direction is at first vertical, with a backward curve on approach-
ing the umbilical parts of the shell.

Locality and Formation.^ — Near the Whippoorwill school,
3| miles northeast of West Union, in the oolitic iron ore at the
top of the Brassfield formation.

Type.^ — The type specimen, used for the original description,
was found in the oolitic iron ore at the top of the Brassfield lime-
stone, on Todd Fork, nearly 3 miles north of the center of Wil-
mington, in Clinton county, Ohio.

Remarks.' — This species is characterized by the prominent
elevation of the median part of the slit-band. In this respect it
resembles typical Lophospira. It appears to have originated
from a shell similar to Lophospira lirata Ulrich, from the Economy
and Southgate members of the Eden formation in the vicinity
of Cincinnati, Ohio. It resembles the latter in the division of
the slope above the slit-band into two revolving concave areas,
and in the tendency toward a faint concave area immediately
beneath this slit-band; it is similar also in possessing revolving
striae along the lower part of the last volution. It is dissimilar
in having these revolving striae much more sharply defined,
much more numerous and present above as well as below the
slit-band.

It would have been far better if Pleurotomaria inexpectans,
instead of Lophospira lirata had been selected as a type of Rue-
demannia, since it appears to be along this direction that Lopho-
spira lirata seems to have varied.

Pleurotomaria rohusta Lindstrom is similar to Lophospira lirata,
in the features mentioned above.

99

MEDINAN, NIAGARAN; AND CHESTER FOSSILS

In Pleurotomaria scutulata Lindstrom and P. gradata Lind-
strom the median part of the slit-band is occupied not by a single
striation but by two, a feature throwing these shells out of align-
ment with Lophospira. In a similar manner the concave slit-
bands of Clathrospira, Plethospira, and Seelya throw these genera
out of alignment with Lophospira and its subdivision Ruede-
mannia.

Cyclonema daytonense Foerste

Cyclonema bilix Foerste, Proc Boston Soc. Nat. Hist. 24, 1889,
p. 290, pi. 5, fig. 15; Geol. Surv. Ohio, Pal., 7, 1893 p. 551, pi.
30, hg. 15.

Cyclonema daytonensis Foerste, 24th Ann. Rep. Indiana
Geol. Nat. Hist. Surv., 1899, p. 77; Journ. Geol., 11, 1903, p. 707.

Cf. Cyclonema bilix Comad, Jour. Acad. Nat. Sci. Philadel-
phia, 8, 1842, p. 271, pi. 16, fig. 10.

The type of Cyclonema daytonense is the specimen figured from
Brown’s quarry, near New Carlisle, Ohio, in 1889, and again in
1893, in the reports cited above. This species is widely dis-
persed, and is one of the most common gasteropoda found in the
Brassfield formation in Ohio, Indiana, and Kentucky. In the
Brassfield limestone of western Tennessee it is found as far south
as Clifton, on the Tennessee river, and it has been cited from
Thebes, Illinois, and Edgewood, Missouri, from the Edgewood
formation.

The species C. bilix was described from Richmond, Indiana,
where only the Elkhorn, Whitewater, and Liberty members of
the Richmond, in descending order, are exposed. The Brass-
field limestone is well exposed at the falls on Elkhorn creek, 3
miles southeast of Richmond.

The forms of Cyclonema found in the Whitewater and Liberty
members are usually erect and relatively tall. Cyclonema bilix
conica Miller^® is the extreme form of this group. It has been

Miller, S. A., The position of the Cincinnati group in the geological column
of fossiliferous rocks of North America: Cincinnati Quart. Jour. Sci., vol. 1, 1874,
p. 320.

100

AUG. F. FOERSTE

well illustrated by Meek^^ and Ulrich. the Waynesville
member of the Richmond the forms are relatively broader.
In the Arnheim, and in the lower part of the Waynesville mem-
bers, there is a form known as Cyclonema fluctuatum James^^
which is not only broad, but which tends to be wrinkled trans-
versely and to be depressed along the upper third of the lower
volutions.

None of these Richmond forms resembles the figure of Cy-
clonema hilix published by Conrad. The latter is not a strongly
erect, conical form, but, on the contrary is low and apparently
with a strongly oblique axis. Shells of this type are relatively
common in the Brassfield limestone, 3 miles southeast of Rich-
mond, while not known in the Elkhorn, Whitewater, or Liberty
members of the Richmond at any locality near Richmond,
Indiana.

The locality and formation assigned by Conrad to his Cyclo-
nema hilix was Richmond, Indiana, in limestones of the age of
the Salmon river series of New York. Conrad included in his
Salmon river series not only strata now known as Lorraine but
also the unfossiliferous sandstone which caps the Lorraine at
the Falls of the Salmon River. This accounts for his use of the
term Salmon River sandstone in his various reports, although
some of the underlying beds contain relatively . thin sandstone
layers also. It is possible that the falls of the Elkhorn were
included in the Salmon River series by Conrad, and that the
type of his Cyclonema hilix was not a Richmond, but a Brassfield
form.

No good purpose, however, would be served by ressurrecting
the name Cyclonema hilix for the Brassfield, instead of the Rich-
mond species. The mere fact that no element of certainty
attaches to its stratigraphic origin suggests that either this name

Meek, F. B., Fossils of the Cincinnati Group: Paleontology of Ohio, vol. I,
1873, pi. 13, fig. 5 g.

32 Ulrich, E. O., and Scofield, W. H., The Lower Silurian Gastropoda of Minne-
sota: Minn. Geol. and Nat. Hist. Surv., vol. 3, 1897, pi. 78, figs. 38-39.

33 Idem: pi. 78, figs. 35, 36, 37.

3“* Idem: pi. 78, figs. 40, 41, 42.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

101

should be dropped, or that Ulrich should be followed in his
definite choice of a type or of a series of types from a definitely
known horizon. Ulrich’s three specimens of Cyclonema hilix^^
figured first under that name in the Paleontology of Minnesota,
from Versailles, Indiana, and Waynesville and Clarksville, Ohio,
are definitely of Richmond age, and their horizon probably was
that of its Waynesville member.

Cyclonema gyronemoides Sp. nov.

Cyclonema bilix varicosum -Foerste, Geol. Surv. Ohio, Pal.,
7, 1893, p. 552, pi. 37A, fig. 9.

Shell with 3 or 4 volutions, rapidly enlarging, the last volution
forming by far the greater part of the shell. In most of the
specimens at hand the spire appears somewhat depressed, simi-
lar to the spire of Cyclonema daytonensis as figured in 1893.^*^
Along the middle and upper thirds of the last volution the shell
is ornamented by strong revolving ridges, usually 5 in number;
revolving striae also are present, but usually these are faint, are
close together, and occur on the ridges as well as on intermediate
parts of the shell. Along the upper half of the lower third of the
last volution there are additional faint revolving striae; along the
lower half of this third, only the transverse striae usually are
present.

The third revolving ridge from the top of the last volution
usually is located slightly above mid-height of this volution, and
the other two ridges are so placed between the third volution
and the suture above that the width of the intermediate concave
spaces decreases only moderately in ascending order. The
fourth revolving ridge occurs at an interval considerably shorter
than that above the third ridge, and is distinctly less conspicuous.
The fifth revolving ridge occurs at a shorter interval than any
of the preceding ridges, and is distinctly less conspicuous than
the fourth ridge.

35 Idem: pi. 78, figs. 35, 36, 37.

35 Foerste, A. F., Fossils of the Clinton Group in Ohio and Indiana: Geol. Surv.
Ohio, Pal. vol. 7, 1893, pi. 30, fig. 15.

102

AUG. F. FOERSTE

The transverse striae are much finer and more crowded than
those of Cyclonema daytonense Foerste,^^ from the same horizon
and general area. Near mid-height of the last volution these
striae form an angle of about 30° or 35° with the vertical axis
of the shell.

Locality and formation.^ — Found at Todd Fork, north of Wil-
mington, Centerville, Dayton, Sharpsville, and east of Danville,
Ohio, in the Brassfield formation.

Remarks. — The only published figure of Cyclonema gyrone-
moides is that found in volume,? of the Geological Survey of
Ohio, on plate 37A, under the name Cyclonema hilix varicosum.
This figure was based on a series of fragments of which the largest
and most important consisted chiefly of the upper part of the
last whorl, including the 5 prominent revolving ridges. The
basal part of the last volution and the aperture were added from
other specimens. This aperture evidently is that of a Cyclonema,
and it remains to be shown that the species here described as
Cyclonema gyronemoides possessed’ this type of aperture. At
the time the figure was prepared numerous specimens of this
species were at hand. Those recently collected do not show the
aperture. In the published figure the spire appears to be much
taller than in the specimens now at hand, possibly owing to the
specimen being viewed from its narrowest aspect. However,
here, again, there is a possibility of the apical part of the figure
having been derived from some other specimen. In the speci-
mens now at hand the spire is relatively depressed, somewhat as
in the figure of Cyclonema daytonense published on plate 30 of
the volume cited above, under the name Cyclonema hilix. Under
these circumstances only the upper part of the last volution of
figure 9 on plate 37A of the volume cited is to be regarded as
unequivocally typical of the species Cyclonema gyronemoides;
this part includes the 5 prominent revolving ridges. The re-
mainder of the figure may be correct, but the specimens from
which it was prepared have been lost, so that the accuracy of
the remainder of this composite drawing can not be verified.

Idem: pi. 30, fig. 15.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

103

While not common, as in case of Cyclonema daytonense, speci-
mens of Cyclonema gyronemoides are widely distributed in the
Brassfield of Ohio, and form one of its characteristic species.
Apparently the latter is not a species of Gyronema. In that
genus there is a distinct umbilicus, though small, and the inner
margin of the aperture is not reflexed so as to cover this um-
bilicus.

Diaphorostoma clintonense (Foerste)

Platyceras Niagarense var. Clintonense Foerste, Geol. Surv.
Ohio, Pal. 7, 1893, p. 554, pi. 37a, fig. 8.

The type of this species was a specimen with a very low,
closely coiled spire, but with the last half of the last volution
curving strongly downward. It was found in the ferruginous
limestone at the top of the Clinton, just under the Onondaga
shales, near Mifflintown, in Juniata county, Pennsylvania.

Diaphorostoma daytonense Sp. nov.

Platyostoma Niagarense Foerste, Bull. Sci. Lab. Denison
Univ., 1, 1885, p. 97, pi. 13, figs. 3 a; fig. 22 a, b.

Platyceras (Platyostoma) Niagarense Foerste; Geol. Surv.
Ohio, Pal. 7, 1893, p. 553, pi. 25, figs. 3 a; figs. 22 a, b.

The Brassfield form differs from the typical Rochester shale
form of Diaphorostoma niagarense (Hall) in possessing a lower
spire, the height of the body whorl is greater, and there is less
tendency toward the production of broad revolving ridges and
grooves; it does not attain as large a size, and the transverse
striae are finer. Only gerontic forms present the large apertures
represented by figure 22 in the plates cited above. Most speci-
mens resemble figure 32 on these plates, but with about 2 mm.
added to the lateral extent of the last volution. Specimens
resembling figure 3b on these plates are very rare, and represent
merely aberrant individuals. For these Brassfield forms the
name Diaphorostoma daytonense is proposed.

104

AUG. F. FOEESTE

Onychochilus abruptum (Foerste)

Paleopupa abrupta Foerste, Geol. Surv. Ohio, Pal., 7, 1893,
p. 556, pi. 37A, fig. 21 a, b.

The genus Onychochilus was proposed by Lindstrom in 1881,
in his Silurian Gasteropoda of Gotland, three species, Onycho-
chilus physa, On. reticulatum, and On. cochleatum being described
by him in the order named, the latter doubtfully referred to the
genus. Of these the first named, Onychochilus physa, here is
regarded as the type.

The specific name physa indicates the sinistra! curvature of
the spire of the type species, a feature shared by all three species
described by Lindstrom, and also by the peculiar gasteropod
described by me under the generic term Paleopupa. The choice
of the name Paleopupa as a generic term for a sinistral shell is
unfortunate, since the Brassfield species so designated could not
have been ancestral to any form of Pupa. Its resemblance to
Pupa ends with its rapid apical expansion, followed by a much
slower expansion along the last volution. Nothing is known of
its surface ornamentation.

In Onychochilus physa the aperture is obliquely rounded, the
lower margin being distinctly angulated. There is no trace of
an umbilicus. The surface striation is transverse. In Onycho-
chilus reticulatum the angulation at the base of the aperture is
even more pronounced. Vertical sections show that the umbili-
cal passage through the axial part of the shell has been closed by
a callous deposit. The surface is ornamented by both transverse
and revolving striae, readily seen under a lens. In both species
the rate of increase in size is more even than in Paleopupa dbrupta,
and in the latter species no angulation of the base of the aperture
was noted, but this part was not well preserved in the specimens
studied.

Nothing appears to be known of the relationship of Onycho-
chilus, and the term does not appear in Zittel-Eastman’s Text-
book of Paleontology.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

105

G. NIAGARAN FOSSILS FROM JEPTHA KNOB, KENTUCKY

Jeptha Knob is a conspicuous elevation of land 6 miles south-
east of Shelbyville, in Shelby county, Kentucky. The knob
attains an elevation of about 1300 feet above sea level. Its
upper levels consist of Richmond strata, but on its upper parts
are found also residual fragments of Silurian strata, showing
that it had once been overlain by the latter. Among the latter
may be recognized a few fragments of crystalline limestone, which
both lithologically and paleontologically can be identified as of
Brassfield age. Most of the Silurian fragments however consist of
flat pieces of chert. These pieces of chert evidently were derived
from chert layers interbedded in some limestone formation.
Since in the counties directly west of Shelbj^ county, including
Oldham and Jefferson counties, it is the Laurel member of the
Magaran which contains flat layers of chert in abundance, these
Silurian chert fragments on Jeptha Knob are interpreted as also
of Laurel age.

Both Prof. Arthur M. Miller of the University of Kentucky,
and Prof. Walter H. Bucher of Cincinnati University have been
very active in securing fossiliferous fragments of this Laurel
chert, and both have secured fragments of a large species of
Calymene, similar to Calymene cedarvillensis Foerste, but possibly
belonging to a distinct species. The fauna includes

Favosites favosus (Goldfuss)

Lyeilia thebesensis Foerste
Pachydictya cf. bifurcata (Hall)

Dalmanella sp., with fine radiating plications
Dalmanella sp., with very coarse plications
Rhipidomella hybrida (Sowerby)

Platystrophia daytonensis (Foerste). (Plate XV A, fig. 11.)
Schiichertella sp. (Plate XV A, fig. 12.)

Strophonella milleri Sp. nov.

Camarotoechia indianensis (Hall). (Plate XV A, figs. 10 A, B.)
Cypricardinia jepthaensis'Sp. nov.

Hormotoma sublaxa (Conrad) ^

Lophospira bucheri Sp. nov.

106

AUG. F. FOEKSTE

Trochonema sp., resembling Trochonema beloitense Whitfield in
having two lateral revolving ridges, and one ridge near the
upper suture, but entire height of shell only 10 mm., and with
more acute apical angle. (Plate XV A, fig. 7.)

Calymene cf. cedarvillensis Foerste

Illaenus daytonensis Hall and Whitfield. (Plate XV A, fig. 13)

Lyellia cf. thebesensis Foerste
Plate XV ^ fig. 8

Lyellia thebesensis Foerste, Bull. Sci. Lab. Denison Univ., 14,
1909, p. 95, pi. 4, fig. 69.

Corallum 70 mm. in width and 45 mm. in height; maximum
size unknown. Coralhtes averaging 1.5 mm. in diameter, the
distances between the corallites averaging between 0.4 and 0.5
mm., two and a half to three corallites occurring in a length of
5 mm. The corallites are tubular in form and are crossed by 8
to 13 tabulae in a length of 5 mm. The spaces between the
corallites are crossed by vesicular tissue, the plates of which
sometimes are not much closer together than the tabulae within
the corallites. Wlien the corallum is viewed from above, this
vesicular tissue frequently has a more or less radiating appear-
ance.

Locality and formation.- — In the loose chert, assumed to be
of Laurel age, on Jeptha Knob, Kentucky.

Strophonella milleri Sp. nov.

Plate XIV, fig. 9

Pedicel valve 17.5 mm. long, 23.5 mm. wide at the hinge-line,
with the lateral sides converging at an angle of about 36° from
the postero-lateral angles toward the antero-lateral ones, and
then rounding anteriorly, with a tendency toward angulation in
front, somewhat as in Strophonella costulata Hall and Clarke.
For a distance of 3 to 5 mm. from the. beak the valve is distinctly
convex, but 8 mm. from the beak the curvature reverses to
concave and remains so as far as the margin of the valve. There
is a tendency toward depression also along the median line of

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

107

the valve along its anterior part, as in the species mentioned
above. The radiating striae, however, are much more numerous,
numbering 6 to 8 in a width of 3 mm.

Locality and formation.^ — In the loose chert, assumed to be of
Laurel age, on Jeptha Knob, Kentucky.

Cypricardinia jeptliaensis Sp. nov.

Plate XV A, fig. 6

Right valve 18.5 mm. long, 9.5 mm. high, and 3 mm. deep.
Umbo broad and rounded, near the anterior end of the shell.
The latter extends only about 2 mm. beyond the beak, there
being a faint concave outline between this anterior end and the
beak. The general outline of the shell is transversely elliptical,
highest at the beak and narrowing but moderately posteriorly.
The posterior border is more narrowly rounded than the anterior
one. The greatest depth of the valve is at mid-length. There
is a slight tendency toward flattening in the umbonal area. The
umbonal ridge is weakly defined and lies near the upper margin
of the valve. Growth lines are indicated in directions similar
to those of Cypricardinia arata, but so faint as to be almost im-
perceptible. Compared with the Racine species, the Jeptha
Knob form is more elongate, and its posterior portion is less
elevated; moreover, the umbonal part is broader and flatter.

Locality and formation. — From the loose chert, assumed to be
of Laurel age, on Jeptha Knob, Kentucky.

Lophospira bucheri Sp. nov.

Plate XV A, fig. 9

Shell 40 mm. in height, 32 mm. in maximum width, with a
vertical height of 22 mm. at the aperture, and an apical angle of
60°. There are 6 or 7 volutions. Along the last half of the
last volution there is a salient peripheral angle extending about
1.5 mm. beyond the general convexity of this part of the shell.
Along the corresponding part of the preceding volution the per-
ipheral angle is sharply angular but not salient. Here the upper
part of the last volution conceals the lower part of the preceding

108

AUG. F. FOERSTE

volution to a level 4 mm. beneath the peripheral angle of the
latter, and corresponding concealment is shown along the upper
volutions. Directly over the aperture, the second last volution
shows a prominent revolving striation two-fifths of the distance
from the suture above to the peripheral angle beneath, along the
upper face of the volution. Above and below this revolving
striation the upper face of the volution is gently concave. No
trace of this revolving striation can be detected along the last
half of the last volution. The character of the slit-band on the
peripheral angle can not be determined beyond the fact that it
is not broad and deep as in Phanerotrema. On the last volution
fine striae curve backward from the suture above toward the
peripheral angle, and on the lower side of this angle they curve
at first moderately forward, then vertically downward, and finally
moderately backward toward the umbilicus. Apparently there
are traces of numerous, fine revolving striae, but these traces are
so vague that the presence of such revolving striae can not be
asserted with confidence. Possibly the shell is related to the
group typified by Lophospira inexpectans, but in that case the
trilineate character of the slit-band should be in evidence, even
in a shell whose surface is no better preserved than the one at
hand.

Locality and formation.^ — In the loose chert, assumed to be
of Laurel age, on Jeptha Knob, Kentucky. Named in honor of
Prof. Walter H. Bucher, of the University of Cincinnati.

Calymene cf. cedarviliensis Foerste
Plate XIII, figs. 10 A, B, C

Calymene cedarviliensis Foerste, Bull. Sci. Lab. Denison
Univ., 19, 1919, p. 78, pi. 18, figs. 11 A, B, C.

Fragments of the cranidium, thorax, and pygidium indicate
the presence of a large species of Calymene, certainly equalling
160 mm. and probably equalling 170 mm. in length. It is easily
comparable in size, therefore, with the large specimens of Caly-
mene platys Green from the Schoharie grit of New York.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

109

Compared with Calymene cedarvillensis from the Cedar ville
dolomite at Cedarville, Ohio, the anterior border of the cranid-
ium and the groove intervening between this border and the
anterior margin of the glabella appears relatively broader, from
front to rear, in the Jeptha Knob specimens.

Compared with Calymene vogdesi Foerste, from the Brassfield
limestone of southwestern Ohio, the posterior margin of the
pygidium is more strongly curved; the median axis of the pygid-
ium is relatively broader, and the lateral parts are correspondingly
narrower in the Jeptha Knob specimens. The median groove
on the pleural ribs of the pygidium are distinctly defined only
along the more distal parts of these ribs.

Undoubtedly other distinguishing features would be noted if
better specimens of the Jeptha Knob, Cedarville, and Brass-
field species were at hand.

Orthis bucheri Sp. nov.

Plate XV A, fig. I4

Brachial valve 26 mm. long, estimated to have been 32 mm.
wide; nearly flat, with a shallow median depression. With 17
or 18 primary radiating plications, alternating with which there
is a secondaiy series, not reaching the beak. Both primary and
secondary plications tend to be rather angular along their crests,
and not flattened as in typical Orthis. The structure of the shell
is strongly fibrous.

Locality and formation.^ — South spur of South Hill on Jeptha
Knob, Kentucky; at the base of the crinoidal Brassfield limestone.
Collected by Prof. Walter H. Bucher, in whose honor the species
is named.

H. TRILOBITES FROM THE ST. CLAIR LIMESTONE OF ARKANSAS

Among the trilobites studied by Prof. Gilbert Van Ingen^^ from
the St. Clair limestone at Batesville, Arkansas, the following
never were described or figured: Calymene altirostris, Cyphaspis

Van Ingen, Gilbert, The Silurian Fauna near Batesville, Arkansas, I : School
of Mines Quart., vol. 23, 1901, p. 35.

110

AUG. F. FOERSTE

arkansana, and Cyphaspis spinulocervix. Prof. Van Ingen has
very kindly loaned the types of these species to the writer for
description, and in these descriptions the names proposed by
Prof. Van Ingen have been retained. The collection loaned by
Prof. Van Ingen includes also several specimens of a new species
of Proetus, which I take pleasure in naming after him.

Calymene altirostris Sp. nov.

Plate XIV, figs. 1 A, B, C

Two cranidia are at hand which may not belong to the same
species. The one in which the anterior or rostral border is most
conspicuously elevated undoubtedly is the specimen which
suggested the name altirostris, and must serve as the type of the
species, although it is an inferior specimen otherwise.

Length of cranidium, including the anterior border and the
glabella, but lacking the neck-ring, 5.5 mm. Including the neck-
ring its original length may have been nearly 6.5 mm. The gla-
bella alone is nearly 4 mm. in length, and its maximum width
at the base is estimated at 4.2 mm. The anterior margins of
the lateral lobes are approximately 1.5, 2.5, and 3 mm. from
the posterior margin of the posterior pair of lobes. The anterior
pair is but faintly indicated, while the other two pairs of lobes
and the median part of the glabella are strongly convex. The
general elevation of the anterior part of the glabella above the
lateral parts of the cranidium is about 1.4 mm., and the anterior
or rostral border rises nearly 1 mm. above the general antero-
posterior curvature of the median part of the glabella. Viewed
from in front, the doublure of the rostral part has an elevation
of 1.2 mm., and its face rises at an angle of 95° with the general
horizontal plane of the cranidium, inclining slightly forward
from the vertical. The deep groove between the anterior border
and the glabella is scarcely a third of a millimeter in width. The
anterior margin of the glabella tends to be squarish. The sur-
face of the cranidium is covered by minute granules, visible
onl}’ under a lens.

MEDINAN, NIAGAEAN, AND CHESTER FOSSILS

111

The second specimen belonging to the type series of this species
is much better preserved. Including the neck-ring, the cranidium
is 5.2 mm. in length. The anterior margin of the anterior
border extends 1.3 mm. in front of the glabella, the groove be-
tween this border and the glabella being 0.25 mm. The glabella
tends to be more narrowly rounded anteriorly, and the anterior
or rostral border also appears more narrowly rounded. This
rostral border is strongly elevated anteriorly, but its upper
margin does not rise above the general curvature of the glabella
antero-posteriorly.

Notwithstanding the differences noted, the two individuals
probably belong to the same species,

Calymene sp.

Plate XIV , figs. 2 A, B, C.

Four pygidia of the same general appearance are mounted on
the same small card, and a fifth specimen, loose, was used for a
lateral view. The largest of these originally was 4.8 mm. in
length, 7.8 mm. in width, and had a convexity of slightly over
2 mm. anteriorly. The axial lobe is 3 mm. in width anteriorly
and rises 0.8 mm. above the adjacent partte of the lateral lobes.
The outer part of the lateral lobes curves downward toward the
margin of the pygidium, but without any reversal of curvature
on approaching the latter. The downward curvature begins
along a line corresponding to that described in the case of
Cyphaspis arkanscCna, but the downward curvature along this
line is less abrupt.

The axial lobe bears 2 distinct rings, anteriorly, behind which
there is one ring which is fairly distinct and another ring which
is faintly visible; 1 or 2 additional rings may .be barely per-
ceptible, and 1 specimen shows a seventh ring. The pleural
ribs on the lateral lobes usually are indistinctly marked, except
the anterior 2 or 3 pairs, these anterior ribs being grooved along
their median lines.

It is the absence of any trace of outward curvature along the
margin of the pygidium, and the presence of additional discern-

112

AUG. F. FOERSTE

ible rings on the axial lobe which distinguish the pygidia here
described under the name Calymene from those referred by
Prof. Van Ingen to Cyphaspis arkansana.

Proetus vaningeni Sp. nov.

Plate XIV, figs. 3 A, B, C

Five cranidia are at hand, of which the largest has a length of
5.8 mm. The glabella is 4.7 mm. long, the anterior border of
the cranidium is 1.1 mm. long, and the neck-ring is 1 mm. in
length. The maximum width of the glabella at its posterior
end is 3.9 mm. The glabella is strongly convex, both laterally
and antero-posteriorly. In the latter direction its greatest
convexity is about one-third of the length of the glabella from
its anterior margin. Here the convexity of the glabella is full}^
1 mm. Along the posterior two-thirds of the glabella its antero-
posterior curvature is distinctly less in an antero -posterior di-
rection, though still fairly strong laterally. No trace of a pos-
terior pair of lobes was detected, though the glabella widens
slightly here. In general, the sides of the glabella are nearly
parallel, converging slightly toward the front until the inward
curvature of the facial sutures in front of the palpebral lobes is
reached, but anterior to the latter the sides curve with increasing
rapidity and the anterior margin of the glabella is evenly rounded.
Along the anterior part of the glabella the antero-posterior curva-
ture of the glabella is so strong that this part of the glabella
tends to arch forward over the groove limiting its anterior mar-
gin. No area intervenes between the anterior margin of the
glabella and the median part of the anterior border of the cranid-
ium for a width of a millimeter and a half. The upper surface
of this border is flattish or gently convex, and inclines upward
and forward at an angle of about 160° with the general horizontal
plane of the cranidium. The neck furrow is deep. The neck-
ring is unarmed with any median tubercle as far as known. The
palpebral lobes are 0.75 mm. in width, and their anterior margin
extends 2.4 mm. in front of the rear margin of the glabella. The
surface of the cranidium is almost smooth, even under a lens.

MEDINAN^ NIAGARAN, AND CHESTER FOSSILS

113

One of the small cranidia is 4 mm. in length, but it is well
preserved.

Cyphaspis spinulocervix Sp. nov.

Plate XIV, figs. 4 -d,, B, C

Three specimens belong to the type series. Of these only one
presents the long nuchal spine, and this specimen must, therefore,
be considered the type.

Glabella 1.5 mm. in length; 0.75 mm. in width posteriorly,
including the lateral lobes, 0.8 mm. in width along the neck fur-
row, excluding these lobes. The lobes are 0.6 mm. in length.
The width of the neck-ring is 0.2 mm., and the nuchal spine
extends 1.8 mm. beyond the posterior margin of this ring. The
spine is long and narrow and starts off abruptly from the pos-
terior margin of the ring. The glabella is strongly convex, and
only the posterior margin of the area intervening between the
glabella and the anterior border of the cranidium is shown.

The second specimen retains only the point of attachment for
the nuchal spine, but the spine itself is missing. The remainder
of the specimen, however, is well shown. The length of the
cranidium is 4.1 mm. Of this length 2.5 mm. belongs to the
glabella, 0.4 mm. to the neck-ring, and 1.2 mm. to that part
of the cranidium which is in front of the glabella. The width
of the glabella including the lateral lobes is almost 3 rnm.; ex-
cluding these lobes its width posteriorly is 1.4 mm. The length
of the lobes is 0.9 mm. Their form is ovate. The space between
the anterior margin of the glabella and the anterior border of
the cranidium is 0.8 mm. in length, 0.4 mm. being occupied by
the anterior border. A narrow, deeply impressed groove bor-
ders the anterior and antero-lateral parts of the glabella. In-
mediately anterior to this groove the cranidium is distinctly
convex antero-posteriorly. A similar narrow groove borders
the posterior margin of the anterior border of the cranidium.
This border inclines upward and forward at an angle of about
135° with the general horizontal plane of the cranidium. The
glabella, its lobes, and the area intervening between the glabella
and the anterior border of the cranidium are relatively coarsely

114

AUG. F. FOERSTE

granulated, considering the small size of the specimen, 5 to 6
granules occurring in a distance of 1 mm. Along the neck-ring
and fixed cheeks the granules are less prominent, and along the
anterior border of the cranidium they can be detected with
difficulty.

The third specimen belonging to the type series does not add
to the information given by the preceding specimens.

Cyphaspis arkansana Sp. nov.

Plate XIV, Jigs 5 A, B, C

Four pygidia are present in the type series, and of these the
largest is 3.6 mm. in length, 5.6 mm. in width, and about 2 mm.
in maximum convexity anteriorly. The axial lobe originally
was 2.5 mm. in width anteriorly; at present only the cast of the
lower surface of the pygidium remains. Originally this axial
lobe rose strongly above the adjacent parts of the lateral lobes;
possibly 1 mm. The greater part of the lateral lobes curves
strongly downward toward the lateral margins of the pygidium,
the downward curvature beginning along a line extending from
a point 0.8 mm. from the anterior end of the lateral margin of
the axial lobe diagonally backward and inward, so as to con-
tinue around the posterior margin of the axial lobe in a U-shaped
direction. Parallel to the posterior and lateral margins of the
pygidium, along a line passing immediately posterior to the
axial lobe, there is a faint tendency toward an outward or con-
cave curvature, visible only under favorable illumination. It
may be this faint outward curvature along the margin which
suggested the reference of these pygidia to Cyphaspis, rather
than to Calymene.

The axial lobe bears 2 distinct rings wuth indistinct indications
of a third ring. Posterior to these there is room enough for 3
additional rings, but the surface of the axial lobe here usually
is smooth. The pleural ribs are wxakly indicated. The anterior
pair show median grooves. The third pair is too faintly indicated
to give evidence of grooving. Nothing can be identified dis-
tinctly farther back.

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

115

No glabellae accompany these pygidia belonging to the type
series. I am unable to discriminate between the glabellae of
Cyphaspis, Proetus, and Calymene in specimens of such small size,
but regard Cyphaspis as a possibility in the case of the pygidia
here described.

I. A NEW GASTEROPOD FROM THE GUELPH FORMATION OF OHIO

Straparollus paveyi Sp. nov.

Plate XV, figs. 1 A, B, C

Shell strongly depressed; greatest lateral diameter 63 mm.;
height 37 mm. The spire rises about 20 mm. above the last
volution at its aperture. Volutions at least 5, possibly 6. The
suture between the last volution and that immediatel}^ preceding
is about two-fifths of the height of the latter above its base.
From this suture downward for a short distance the upper part
of the inner outline of the cross-section of the last volution is
distinctly though moderately concave. Along the remainder
of its contour this outline is approximately circular, but slightly
depressed vertically, and with a tendency toward oblique flatten-
ing of that part of its slope which is immediately above mid-height
of the last volution. Near the aperture, the lateral diameter of
the last volution is 23.5 mm., and its vertical diameter is 22 mm.
The oblique flattening above mid-height forms an angle of about
30° with the vertical axis of the shell. The umbilicus is wide
and open, showing all of the volutions; its greatest diameter in
the specimen here described is 20 mm.

Owing to the oblique flattening of that part of the last volution
which is immediately above mid-height there is a tendency toward
a shoulder aboutf three-fifths of the distance between mid-height
and the suture above. From the suture as far as the middle of
the obliquely flattened slope, the transverse striae curve back-
ward at an angle of about 80° with the suture. From this point
the striae curve more strongly backward, at an angle of 60° with
the horizontal, until about 3 mm. below mid-height of the volu-
tion, .beyond which they curve forward until they assume a radial
direction along the lower face of the volution. There is a tend-

116

AUG. F. FOEKSTE

ency toward angulation along the lower margin of the umbilicus,
and within the umbilicus the inner side of the last volution is
striated by relatively coarse transverse lines which curve so as
to present their concave sides toward the aperture of the shell.
In addition to the conspicuous transverse striae, there are very
faint, almost obsolete, revolving ridges, not likely to be noticed
except on exceptionally well preserved specimens.

Locality and formation.^ — Hillsboro, Ohio; from the Guelph
formation. From the collection of Henry Pavey, in whose honor
this species is named. Similar specimens are found in the Ra-
cine of Wisconsin and the Chicago area.

Remarks.- — Straparollus paveyi is regarded as related to the
species described by Lindstrom^^ under the name Oriostoma discors
Sowerby. In the American species the revolving ridges have
become obsolete.

J. A STIGMAEIAN ROOT FROM THE CHESTER FORMATION OF ILLINOIS

Dictyophlois Foerste

In the Bulletin of the Torrey Botanical Club, in 1916, a
Stigmarian root from the Chester formation at Sample, Kentucky,
was described under the new generic name Dictyophlois, the
species itself being named Dictyophlois reticulata Foerste.

Similar Stigmarian roots had long been known in Europe under
the name of Stigmaria stellata or StigmarUa ficoides stellata. As
long ago as 1841, Goeppert illustrated this form of root in his
Gattungen der Fossile Pflanzen (pi. X, fig. 12) from Silesia. It
appears to range from Great Britain as far east as Russia.

In Europe, Stigmaria ficoides stellata appears to range over
about the same territory and at about the same horizon as
Lepidodendron V olkmanriianum Sternberg, which suggests that
Stigmaria ficoides stellata may belong to the root system of
Lepidodendron Volkmannianum. Both appear to be especially
characteristic of the Culm.

In America, Stigmarian roots of this type are confined to the
Chester. • Dictyophlois reticulata, as already stated, was found

Lindstrom, Sil. Gast. and Pter. of Gotland; 1884, pi. 16, figs. 20-36.

MEDINAN, NIAGAEAN, AND CHESTER FOSSILS

117

in the Chester at Sample, in Breckenridge county, Kentucky.
In the State Museum of Natural History at Springfield, Illinois,
there is a specimen of Dictyophlois, numbered 1718, labelled as
coming from the Chester group, at Carroll’s place, in Pope county,
Illinois. This specimen is described and figured on the following
pages. I have been informed by Dr. David White that Stig-
marian roots of the Dictyophlois type are known also in Appa-
lachian areas, in strata of Chester age.

Whether Dictyophlois is to be regarded as founded on differ-
ences of generic value can not be determined until its relationship
to known aerial stems has been definitely established. In our
present state of knowledge it appears to be as distinct as many
another genus. Certainly, the reticulated appearance of the
area between the attachment areas of the so-called rootlets
looks quite different from the corresponding relatively smooth
area in Stigmaria ficoides.

If a knowledge of the bark and wood structure of the so-called
roots or rhizophores of Dictyophlois and of Stigmaria ficoides
were known, it would be possible to determine what is the sig-
nificance of the reticulated structure on the supposed surface of
Dictyophlois. No specimens showing such structure are at
hand. Therefore, I am forced to base my opinions on such
features as are exposed merely by impressions of the surface in
its present condition, without any knowledge as to whether these
features belong to the original surface of the bark, or to more
deep seated structures within this bark.

The American specimens of Dictyophlois do not appear to be
identical specifically with Stigmaria ficoides stellata as figured
by Goeppert. The reticulations between the attachment areas
of the rootlets appear more complicated, although a change of
opinion might be necessary if actual specimens of the European
form were at hand.

The figure accompanying the original illustration of Dictyo-
phlois reticulata unfortunately was printed in an inverted position,
as the location of the shadows might indicate. It was also
printed altogether too pale to bring out all of the structure. This
is remedied by the illustrations of the Illinois specimen here
presented.

118

AUG. F. FOERSTE

Dictyophlois reticulata illinoisensis Var. nov.

Plate XII, and plate XIII, fig. 12.

Cf. Dictyophlois reticulata Foerste, Bull. Torrey Bot. Club,
42, 1916, p. 675, pi. 33.

Plate XII presents the appearance of the specimen in its present
condition. Figure 12 on plate XIII presents the appearance
of an impression of a part of the same specimen, in which the
cavities of the first figure stand out as projections.

Specimen 150 rrtm. in length and about 80 mm. in width; part
of a rhizophore, whose original diameter can not be determined.
In its present condition the specimen is flattened. The view
presented on plate XII is assumed to be that of the exterior of
the cortex. The round areas of attachment of the so-called
rootlets vary from 3 to 4, occsionally 5 mm. in diameter. They
tend to be arranged in diagonally insecting rows, so as to be
from 8 to 13 mm. apart. At these attachment areas the surface
of the rhizophore is abruptly depressed, and from the bottom
of the pit there rises a short circular elevation with a small central
pit. Some of these small central pits have a central tiny eleva-
tion. The round areas of attachment are surrounded by a
single series of radiating depressions, usually from 20 to 25 in
number. These radiating depressions vary usually from 2 to 3
mm. in length, but occasionally are shorter or longer. In the
areas between the radiating groups of depressions the meshes of
the remainder of the reticulated surface usually average about 2
mm. in diameter, though a few may be as much as 3 mm. in
diameter.

Locality and formation.' — From the Carroll place, in Pope
county, in the southern extremity of Illinois, in the Chester
formation.

Remarks. — Evidently the structure of this Illinois specimen
is very similar to that of the Kentucky type. The question
arises whether they are identical. Apparently the zone of radiat-
ing depressions surrounding the attachment areas of the rootlets
tends to be depressed below the general level of the surface in
the Kentucky type, while in the Illinois specimen the descent

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

119

into the pit at the attachment area is more abrupt; but this may
be due to inferior preservation of the Kentucky type. In the
Kentucky type these attachment areas vary from 13 to 15 mm.
in their distances apart as an average, and considering this
moderately greater distance apart, the meshes of the reticulated
surface between appear relatively coarser. In fact, this differ-
ence in the coarseness of the intervening meshes appears sufficient
to warrant the use of a distinguishing name for the Illinois speci-
men, which therefore is called variety illinoisensis of the Kentucky
type of Dictyophlois reticulata.

BIBLIOGRAPHIC REFERENCES
Stigmaria stellata Eichwald

Eichwald: Bull. Acad. Imp. Sci. St. Petersburg, vol. 7, 1840, p. 90. Russia:
Prikscha. — Upper Carboniferous.

Eichwald: Lethaea Rossica, Stuttgart, vol. 1, i, 1860, p. 206, pi. xv, fig. 2.
Renault: Cours Bot. Foss., vol. 1, 1881, p. 155.

Stigmaria ficoides stellata Goppert

Goppert: Gatt. Foss. Pflanzen, pts. 1 and 2, 1841, p. 64, pi. x, fig. 12. Silesia:

Landshut. — Upper Carboniferous (Jiingste Grauwacke).

Goppert: Naturk. Verb. Holl. Maatsch. Wetensch., Haarlem, vol. 4, 1848, p. 78,
pi. xii, figs, xxi, xxii.

Schimper: In Koechlin-Schlumberger: Mem. Soc. Sci. Nat. Strasbourg, vol.
5, 1862, p. 326.

Dawson: Canadian Nat., vol. 8, 1863, p. 436 (6).

Goppert: Palaeontographica, vol. 12, (Perm. Form.) 1864, p. 198.

Lesquereux: Second Geol. Surv., Pa., Rept. Progr. P (Coal FL, vol. 2), 1880, p.
515, pi. Ixxiv, fig. 4.

Lesquereux: 13tli Ann. Rep. Indiana Geol. Surv., Indianapolis, 1883 (1884),
p. 96, pi. xix, fig. 4.

Lesley: Rept. Geol. Surv. Pa., P4, (Diet. Foss. Pa. vol. 3), 1890, p. 1074, one text
fig.

Lepidodendron Volkmannianum Sternberg

Sternberg: Flora der Vorwelt, 1, (Tentamen), 1825, p. x, pi. liii, figs. 3a-c.

Silesia: Zaborze; Waldenburg — Upper Carboniferous.

Unger: Gen. et Spec. PI. Foss., 1850, p. 256.

Quenstedt: Handb, Petrefactenk., Tubingen, 2nd ed., 1867, p. 871, pi. Ixxxi,
fig. 22; 3d ed. 1885, p, 1121, pi. xciv, fig. 17.

Schimper: Pal. Veg., vol. 2, 1870, p. 23.

Stur: Abh. k. k. Geol. Reichsanst., vol. 8, no. 2, (Culm. FL, pt. 2), 1877, p. 286
(392), pi. xviii, fig. 4: pi. xxiii, figs. 2-5.

Feistmantel: Palaeontographica, Suppl. 3, no. 3 (FI. Austr.), 1879, p. 152, pi.
xxiii, fig. 1.

120

AUG. F. FOERSTE

Rothpletz : Botanisches Centralblatt, vol. 1-2, 1880, III. Gratis-Beilage, No. 1,
p. 26, pL ii, figs. 2, 8, 10.

Weiss: FI. Steinkohlen f. Breuss., Berlin, 1881, p. 7, pi. iv, fig. 29.

Renault: Cours Bot. Foss., vol. 2, 1882, p. 17, pi. 1, fig. 8.

Toule: Schrift. Ver. Verbr. Naturw. Kennt., vol. 28, 1888, p. 680, pi. iii, figs.
13-14.

Kidston: Records Geol. Surv. N. S. Wales, vol. 1, pt. 2, 1889, p. 115, pi. v, N. S.

Wales: Goonoo Goonoo. — Lower Carboniferous(?)

Feistmantel : Mem. Geol. Surv. N. S. Wales, Sydney. Palaeontographica, no. 3,
1890, pi. 141, pi. xi, fig. 1.

Zimmermann: Verb. Naturf. Ver. Brunn, vol. 30, 1892, Abb., p. 120.

Potonie: Abb. k. preuss. Geol. Landesanstalt (N. F.') no. 21, 1896, p. 43, text
fig. 43.

Potonie: Naturw, Wochenschr., Berlin, vol. 13, 1898, p. 216, text fig. 7.

Potonie: Lehrburch Pflanzenpalaeont., Berlin, 1898, p. 222, text fig. 216.
Hofmann AND Ryba: Leitpfl. Palaeoz. Steinkohl., Prag, 1899, pi. 81, p. xv, figs. 2, 3.
Potonie : In Engler and Prantl, Natural Pflanzenfam., Leipzig, 1 Teil, 4. Abth.,
1901, p. 725, text figs. 419-420.

Potonie: Abb. k. preuss. Geol. Landesanstalt., (N. F.), no. 36, 1901, p. 113,
text figs. 68-71.

Prussian Saxony: Lautenthal, Grund — ^Culmgrauwacke.

Kedston: Trans. Royal. Soc. Edinburg, vol. 40, 1903, p. 21, pi. ii, fig. 19.
Fischer: In Potonie, Abb. Bescbr. Foss. Pfl. Pal. Mes. Form. pt. 3, no. 41, 1905,
p. 6, text figs. 4, 7; no. 51, p. 2, text figs. 1-5. Saxony: Magdeburg. —
(Culm) Lower Carboniferous.

Gothan: Aus der Natur, Leipzig, vol. 1, 1906, p. 613, text fig. 6.

Arber: Sci. Proc. Royal Dublin Soc., vol. 13 (N. S.), no. 12, 1912, p. 171, pi. x,
fig. 1 : pi. xii, fig. 14.

Ireland: Ballycastle Coalfield, County Antrim — Lower Carboniferous.
Bureau Bass: Basse Loire, pt. 2, FI. Foss., Atlas, 1913, pi. Ivii, figs. 1-3: pi.
Iviii, figs. 1-4A: pi. lix, figs. 3-4A; Text, 1914, p. 124.

France: Tardiviere, Moused, Prejean, Basse Loire. — Upper Culm.

Potonie: Lehrb. Pflanzenpal., 2nd ed., 1921 (?), p. 196, text fig. 168.

PLATE IV

Fig. A. Leveilleites hartnageli Foerste. Type, in same slab with Dictyonema
scalariforme creditensis Foerste. Specimen belonging to Chris Andrew Hart-
nagel.

Fig. B. Dictyonema scalariforme creditensis Foerste. Type, magnified 1.7
diameters. The lower part of the specimen presents the proximal side and the
upper part the distal side of the same infundibuliform rhabdosome.

Fig. 25. Leveilleites hartnageli Foerste. Both obverse and reverse of the speci-
men are present. Enlarged views occur on plate IX.

Fig. 26. Leveilleites hartnageli Reverse of specimen 5. Enlargements

of specimens 26 and 5 occur on plates VII and X.

All specimens on this plate are from the base of the Manitoulin dolomite
member of the Medinan, in the quarry west of Credit Forks railroad station, in
Ontario.

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE IV

AUG. F. FOERSTE

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

PLATE V

Figs. 1-12. Leveilleites hartnageli Foerste, associated with Dictyonema scalari-
forme creditensis Foerste in specimens 4 and 12. Credit Forks, Ontario; in the
Manitoulin dolomite.

The fronds in the upper right hand corner of figure 2 are the reverse of those
in figure 15 on plate VI.

Of specimen 3 both the obverse and reverse are present, and frond A is enlarged
on plate VII.

Specimen 5 is the reverse of specimen 26 figured on plate IV, and both are
figured enlarged on plates VII and X.

Of specimen 6 both the obverse and reverse are present, and a third fragment
contains Dictyonema scalariforme creditensis .

Specimen 7 is the reverse of specimen 21, frond B in figure 7 and frond A in
figure 21 being the frond enlarged in figure 21 on plate IX. Specimen 8 is the
reverse of the opposite side of specimen 21, no part of which is shown in figure 7.

Frond A in figure 8 is enlarged on plate VIII.

PLATE V

Bulletin Scientific Laboratories Denison University Vol. XX

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

PLATE VI

Figs. 13-24, Leveilleites hartnageli Foerste. From Credit Forks, '^Ontario,
in the Manitoulin dolomite.

Specimen 13 is the reverse of specimen 17.

Specimen 15 is the reverse of the upper part of specimen 2.

Specimen 16 is the reverse of specimen 22.

Specimen 18 is the reverse of specimen 19, and is enlarged on plate XI*
Specimen 21 is the reverse of specimen 7, and is enlarged on plate IX.

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE VI

AUG. F. FOERSTE

MEDINAN, NIAGARAN. AND CHESTER FOSSILS

PLATE VII

Fig. 3A. Leveilleites hartnageli Foerste. From Credit Forks, Ontario. View
of frond 3A on plate V enlarged 10 diameters. Showing trace of median rachis-
like film.

Fig. 5. Leveilleites hartnageli Foerste. From Credit Forks, Ontario. View of
frond in figure 5 on plate V, enlarged 10 diameters. Reverse of specimen 26.
Reticulated structure of frond shown vaguely in dark part of figure. See also
plate X.

Fig. 26. Leveilleites hartnageli Foerste. From Credit Forks, Ontario. View of
frond A in figure 26 on plate IV, enlarged 10 diameters. Showing the reticulated
structure of the frond.

Photographs by Prof. George H. Hudson, of Plattsburgh, New York; this and
the following four plates have been photographed under gum dammar in order
to bring out the structural details. Plates X and XI should be examined
under a stereoscope.

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE VII

AUG. F. FOERSTE

MEDINAN, NIAGARAN. AND CHESTER FOSSILS

PLATE VIII

Fig. 8. Leveilleites hartnageli Foerste. From Credit Forks, Ontario. View of
frond A in figure 8 on plate V. The middle figure is enlarged 4 diameters. The
right hand figure, enlarged 10 diameters, represents the upper half of the same
frond, while the left hand figure, also enlarged 10 diameters, represents the lower
part of this frond. All figures show the median rachis-like black film. There
are traces also of the reticulated structure.

Photographs by Prof. George H. Hudson.

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE VIII

AUG. F. FOERSTE

MEDINAN, NIAGARAN, AND CHESTER FOSSILS ] }

PLATE IX

Fig. 21. Leveilleites hartnageli Foerste. From Credit Forks, Ontario. View
of frond A in figure 21 on plate VI, enlarge 14 diameters. The median rachis-like
black film with traces of corresponding lateral films are shown.

Fig. 25. Leveilleites hartnageli Foerste. From Credit Forks, Ontario. The left
hand figure is enlarged 4 times, and the middle figure is enlarged 8 times. The
middle figure is an enlargement of frond A in the preceding figure, and both figures
are enlargements of figure 25 on plate IV. These enlargements show the median
rachis-like black films of the fronds and of their lateral lobes, and the reticulated
structure of the fibrous mass forming the fronds. Along the left margin of the
middle figure on this plate the hair-like fibers attached to the frond are visible in
the photograph, but do not show up well in the photoengraving.

Photographs by Prof. George H. Hudson.

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE I X

AUG. F. FOERSTE

MEDINAN, NIAGARAN. AND CHESTER FOSSILS

PLATE X

Fig. 5. Leveilleites hartnageli Foerste. From Credit Forks, Ontario. Both
views enlarged 10 diameters, arranged for use with a stereoscope. Same specimen
as figure 5 on plate V. This stereoscopic view is valuable chiefly for showing that
the fronds consist of something more than a thin flat carbonaceous film. They
consist of reticulating fibers occupying a visible depth of space. Some of the
black dots to which the hair-like fibers were attached are visible in the photo-
graphs, and a few of the hair-like fibers are seen.

Photographs by Prof. George H. Hudson.

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE X

AUG. F. FOERSTE

MEDINAN, NIAGARAN. AND CHESTER FOSSILS

PLATE XI

Fig. 18. Leveilleites hartnageli Foerste. From Credit Forks, Ontario. Both
views are enlarged 10 diameters, arranged for use with a stereoscope. Same
specimen as figure 18 on plate VI. This stereoscopic view is valuable chiefly for
showing that the fronds consist of something more than a thin flat carbonaceous
film. Some of the individual fibers can be recognized along the margin of the
frond.

Photographs by Prof. George H. Hudson.

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE XI

AUG. F. FOERSTE

MEDINAN, NIAGARAN. AND CHESTER FOSSILS

PLATE XII

Dictyophlois reticulata illinoisensis Foerste. Apparently the outer surface of
the bark of one of the rhizophores, showing the circular areas of attachment of

See Plate XIII for a
From Carroll place,

the so-called rootlets, and the intervening reticulated area,
figure of an impression in clay of part of this specimen,
in Pope county, Illinois.

Specimen No. 1718, State Museum of Natural History, Springfield, Illinois.

Bulletin Scientific Laboratories

Denison University Vol. XX

PLATE XII

AUG. F. FOERSTE

MEDINAN, NIAGARAN. AND CHESTER FOSSILS

PLATE XIII

Fig. 1. Modiolopsis orthonota perumbonata Foerste. Right valve. Credit
Forks, Ontario; Whirlpool sandstone.

Fig. 2. Modiolopsis orthonota (Conrad). A-E, right valves; F, G, left valves.
Credit Forks Ontario; Whirlpool sandstone.

Fig. 3. Ctenodonta (?) creditensis Foerste. Left valve. Credit Forks, Ontario;
Whirlpool sandstone.

Fig. 4. Ctenodonta (?) cataractensis Foerste. Left valve. Credit Forks,
Ontario; Whirlpool sandstone.

Fig. 5. Ctenodonta (?) sp. Left valve. Credit Forks, Ontario; Whirlpool
sandstone.

Fig. 6. Schuchertella creditensis Foerste. Pedicel valve, showing location and
length of dental lamellae. Credit Forks, Ontario; Whirlpool sandstone.

Fig. 7. Dahnanella eugeniensis Williams. Brachial valve. Credit Forks,
Ontario; Whirlpool sandstone.

Fig. 8. Whitfieldella circularis Foerste. Brachial valves. Credit Forks,
Ontario; Whirlpool sandstone.

Fig. 9. Lingula cf. cuneata Conrad. Brachial valve. Credit Forks, Ontario;
Whirlpool sandstone.

Fig. 10. Calymene cf. cedarvillensis Foerste. A, cranidium. B, fragment of
four segments of thorax. C, pygidium. From residual chert, regarded as belong-
ing in the Laurel member of the Niagaran, loose on top of Jeptha Knob, in
Shelby county, Kentucky.

Fig. 11. Liospira (?) sp. Credit Forks, Ontario; Whirlpool sandstone.

Fig. 12. Dictyophlois reticulata illinoisensis Foerste. Clay cast of part of sur-
face of the specimen illustrated on plate XII.

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE XIII

AUG. F. FOERSTE

MEDINAN, NIAGARAN. AND CHESTER FOSSILS

PLATE XIV

Fig. 1. Calymene altirostris (Van Ingen) Foerste. A, cranidium. B, C, lateral
and upper views of cranidium of chief type. St. Clair Spring, Independence
county, Arkansas; St. Clair member of Niagaran. Types. Van Ingen collection.

A, magnified 3 diameters; B, C, 2 diameters.

Fig. 2. Calymene sp. A, B, C, three pygidia. C, lateral view. St. Clair Spring,
Independence county, Arkansas; St. Clair member of Niagaran. Van Ingen
collection. Magnified 3 diameters.

Fig. 3. Proetus vaningeni Foerste. A, B, C, three cranidia. St. Clair Spring,
Independence county, Arkansas; St. Clair member of Niagaran. Van Ingen
collection. Magnified 3 diameters.

Fig. 4. Cyphaspis spinulocervix (Van Ingen) Foerste. A, B, C, three cranidia.

B, C, showing the points of attachment of the nuchal spine. St. Clair Spring,
Independence county, Arkansas; St. Clair member of Niagaran. Van Ingen
collection. Magnified 3 diameters.

Fig. 5. Cyphaspis arkansanum (Van Ingen) Foerste. A, B, C, three pygidia,
with a tendency toward a faint marginal depression. St. Clair Spring, Independ-
ence county, Arkansas; St. Clair member of Niagaran. Van Ingen collection.
Magnified 3 diameters.

Fig. 6. Straparollus pervetustus (Conrad). Viewed slightly obliquely, so as to
show more of the spire. Lockport, New York; from the Medinan. Original of
fig. 3a on plate 4 bis. Pal. New York, 1, 1847. Specimen No. 1434-1, American
Museum of Natural History.

Fig. 7. Modiolopsis orthonota (Conrad). A, right valve; B, left valve. Origi-
nals of figures la, lb, Ic, on plate 4 bis. Pal. New York, 1, 1847. A, from Medina,
New York; B, from Lockport, New York; both from the Medinan. Specimen A,
No. 1433-1; specimen B, No. 1433-2, in the American Museum of Natural History.

Fig. 8. Modiolopsis primigenia (Conrad). Left valve, cast of interior, showing
hinge-tooth. Lockport, New York, in the Medinan. Original of fig. 2a on plate
4 bis. Pal. New York, 1, 1847. Specimen No. 1432-2, American Museum of Natural
History.

Fig. 9. StrophonellamilleriP OQYstQ. Pedicel valve. Jeptha Knob, Kentucky,
in loose chert from the Laurel formation.

Fig. 10. Dalmanites sp. Fragment from right side of pygidium; outline of
pygidium unknown. Centerville, Ohio; from basal Silurian, beneath Brassfield
limestone.

Fig. 11. Leptaena center villensis Foerste. A, pedicel valve, interior; B, cast of
same, to show convexity of valve. Concentric wrinkles are present, as described
in the text, but do not show in the photograph, since the direction of illumination
chosen was that which brought out the details of the muscular area, rather than the
wrinkles. Centerville, Ohio; from the upper part of the Brassfield limestone.

Fig. 12. Brachyprion sp. Interior of pedicel valve. Centerville, Ohio; from
basal Silurian, beneath the Brassfield limestone.

Fig. 13. Schuchertella subplana brevior Foerste. Pedicel valve. Centerville,
Ohio; from the basal Silurian, beneath the Brassfield limestone.

Fig. 14. Whitfieldella cf. ovoides Savage. A, lateral view; B, cast of interior
of pedicel valve. Centerville, Ohio; from the basal Silurian, beneath the Brass-
field limestone.

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE XIV

AUG. F. FOERSTE

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

Fig. 15. Rhijncliotretathebesensis 'FoQvs>iQ. Brachial valve. Centerville/Ohio;
from the basal Silurian, beneath the Brassfield limestone.

Fig. 16. Liospira depressum Foerste. A, apical view; B, basal view, showing
callosity on one side of umbilicus. Centerville, Ohio; from the basal Silurian,
beneath the Brassfield limestone.

Fig. 17. Lophospira ehlersi Foerste. A, apical part of specimen; B, same
specimen enlarged, C, D, entire specimens. Centerville, Ohio; from the basal
Silurian, beneath the Brassfield limestone.

Fig. 18. Lophospira {Ruedemannia f) centervillensis Foerste. A, fragment
showing the typical revolving striae along the lower part of the last volution; B,
entire specimen, showing general form of shell. Centerville, Ohio; from the
basal Silurian, beneath the Brassfield limestone.

Fig. 19. Ctenodonta cf .simulatrix Ulrich. A., left valve; B, right valve; both
magnified 2.4 diameters. Centerville, Ohio; from the basal Silurian, beneath the
Brassfield limestone.

Fig. 20. Bellerophon centervillensis Foerste. A, aperture facing upward, but
margin brokin off; B, enlarged view of the same. C, aperture facing downward,
but margin broken off. D, attempt at restoration of the margin, in a lateral view.

PLATE XV

Fig. 1. Straparollus paveyi Foerste. A, lateral view; B, apical view; C, umbilical
view, Hillsboro, Ohio; from the Guelph formation.

Fig. 2. Spyroceras microtextile Foerste. A, small fragments; B, the same
enlarged; this fragment shows the vertical and transverse striae described in the
text, but a greater magnification is needed to show these. C, a longer specimen,
apparently belonging to the same species. Centerville, Ohio; from the basal
Silurian, beneath the Brassfield limestone.

Fig. 3. Loxoceras husseyi Foerste. A, a small fragment showing the vertical
surface striae; B, enlargement of the same; C, a typical specimen of larger size,
showing the camerae; D, vertical section, showing two of the segments of the
siphuncle, and faint traces of two more. Centerville, Ohio ; from the basal Silurian
beneath the Brassfield limestone.

Fig. 4. Hor^notoma trilineata var. Foerste. Specimen with a shorter spire
than usual. Centerville, Ohio; from the basal Silurian, beneath the Brassfield
limestone.

Fig. 5. Hormotoma trilineata var. Foerste. Specimen with shorter volutions
than usual. Centerville, Ohio; from the basal Silurian, beneath the Brassfield
limestone.

Fig. 6. Hormotoma trilineata Foerste. A, typical form; B, enlargement of the
same; C, another specimen. Centerville, Ohio; from the basal Silurian, beneath
the Brassfield limestone.

Fig. 7. Hormotoma centervillensis Foerste. A, lateral view; B, enlargement of
the same. Centerville, Ohio; from the basal Silurian, beneath the Brassfield
limestone.

Fig. 8. Lyellia thebesensis Foerste. Jeptha Knob, Kentucky, from loose
chert referred to the Laurel formation.

BuLLETtN Scientific Laboratories Denison University Vol. XX

PLATE XV

AUG. F. FOhRSTE

MEDINAN, NIAGARAN, AND CHESTER FOSSILS

PLATE XV-A

Fig. 1. Dalmanites sp. Cranidium with adjacent parts of free cheeks; middle
part of anterior outline uncertain. Strongly convex cranidium apparently re-
lated to Dalmanites vigilans Hall. Cedarville, Ohio; in Cedarville dolomite.

Fig. 2. Dalmanites sp. Pygidium associated in same layers with the latter;
tip of posterior outline uncertain. Cedarville, Ohio; in Cedarville dolomite.

Fig. 3. Dalmanites cf. Illinoisensis Weller. Pygidium. Moodie quarry, at
Wilmington, Ohio; in the Cedarville dolomite. Collection of Dr. George M.
Austin.

Fig. 4. Cheirurus welleri Raymond. Hypostoma. Moodie quarry at Wilming-
ton, Ohio; in Cedarville dolomite. Collection of Dr. Charles Welch.

Fig. 5. Cheirurus welleri Raymond. Cranidium with posterior part restored.
Moodie quarry at Wilmington, Ohio; in Cedarville dolomite. Collection of
Dr. Charles Welch.

Fig. 6. Cypricardinia jepthaensis Foerste. Right valve. Loose chert, of
Laurel age, on Jeptha Knob, Kentucky.

Fig. 7. Trochonema sp. Loose chert of Laurel age, on Jeptha Knob, Kentucky.

Fig. 8. Eccyliomphalus circinatus (Whiteaves). Apical end of shell with septa.
Five-eighths of a mile northeast of Steam Furnace, south of Peebles, Ohio; in
strata equivalent to the Guelph formation.

Fig. 9. Lophospira bucheri Foerste. Loose chert of Laurel age, on Jeptha
Knob, Kentucky.

Fig. 10. Camarotoechia indianensis (Hall). A, brachial valve; B, pedicel
valve. Loose chert of Laurel age, on Jeptha Knob, Kentucky.

Fig, 11. Platystrophia daytonensis (Foerste). Pedicel valve. Loose chert of
Laurel age, on Jeptha Knob, Kentucky.

Fig. 12. Schuchertella sp. Loose chert of Laurel age, on Jeptha Knob,
Kentucky.

Fig. 13. Illaenus cf. daytonensis Hall and Whitfield. Loose chert of Laurel age,
on Jeptha Knob, Kentucky.

Fig. 14. Orthis bucheri Foerste. Brachial valve. From residual Brassfield
limestone at south spur of South Hill, on Jeptha Knob, Kentucky. Named in
honor of Dr. Walter H. Bucher.

Fig. 15. Buthotrephis creditensis Foerste. A, Type specimen, with fragment
of frond. B, lobate portion of another frond. Credit Forks, Ontario; in basal
part of Manitoulin dolomite.

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE XV-A

AUG. F. FOERSTE

MEDINAN. NIAGARAN. AND CHESTER FOSSILS

THE EGG AND LARVA OF HESPERIA JUBA BDV.

A. W. LINDSEY

During the last two weeks of June and early in July, 1922,
while the writer was collecting in Modoc County, California,
juba was on the wing in large numbers. The females were much
more numerous than the males, and the prospect of adding a
life history of this fine species to our scanty knowledge of the
early stages of the Hesperioidea seemed good. Most of the
specimens collected, however, were taken on the flowers of a
small composite which grew on a dry hillside, and no eggs were
obtained until June 29, when a female was observed to place one
on a blade of grass at the edge of a small irrigation ditch. This
was in a hay field, and the grass was so immature that it could
not be identified — a matter which proved immaterial, since the
larva ate every species offered to it. Only the one egg was
secured. It gave promise of furnishing the complete life history,
but the necessity of transporting the larva at the end of the
season proved fatal. It ate grasses found at Los Angeles, almost
5000 feet lower in altitude than its native region, and passed
its fourth moult in that city, but was then attacked by a mold
which caused its death.

Little work of a soundly scientific character has been done on
the larvae of the Hesperioidea, hence these notes must be re-
garded as a pioneer attempt to use the results obtained in the
study of other lepidopterous larvae. Prominent among such
studies are the recent writings of Mr. Carl Heinrich of the Na-
tional Museum on the larvae of microlepidoptera. An attempt
has been made to follow these papers in the study of the head
capsules of the juha larva, and Heinrich^s use of Dyar^s system
of nomenclature of the primary body setae has also been adopted
in preference to the rather elaborate method of Fracker.^

1 Fracker, S. B., Class. Lep. Larvae. 1915.

121

122

A. W. LINDSEY

It is unfortunate that so little material could be preserved
for this study, but the complete series of head capsules, the setal
map of an abdominal segment of the first instar (fig. 4),
sketched in the field, and the maps made from the preserved body
in the fifth instar, show some interesting and suggestive things
with regard to the possible basis of classification of skipper larvae.
It is obvious from the notes recorded that (1) a reduction of
primary setae occurs during the first ecdysis, both on head and
body, and that (2) it is accompanied by an assumption of a
prominent vestiture of secondary setae. The secondary setae
of the body have been apparently glandular or sensory in all
species observed by the writer. Since the change in vestiture
after the first instar agrees with the writer’s memory of findings
published by Dyar in a paper at present unavailable, it is prob-
ably a factor which must be contended with in the entire super-
family, with the possible exception of the Megathymidae and
Euschemonidae. The possible persistence of primary setae or
tubercles has been pointed out by Tracker, ^ but without any
attempt to interpret specific cases. This attempt is made here,
although it must necessarily be supported by other observations
before it can be more than a suggestion.

The following paragraphs on the egg and larval stages give
the writer’s field notes, supplemented by measurements of the
head capsules. These are followed by a brief discussion of the
chaetotaxy of the larva, based, with the exception of the first
instar, upon the preserved fifth stage larva and the head capsules.

Egg: Deposited June 29, about 2:00 p.m., in a damp sunny
place close by the edge of a small irrigation ditch, where the
humidity must have been much higher than in the localities
frequented by the adults. The egg was circular, its flattened
base about 1 mm. in diameter. Its height was about 0.75 mm.,
the sides rounding up to a flattened micropylar area about 0.4
mm. in diameter. Shell white with a yellowish tinge due to the
contents. Surface covered with a fine reticulation of raised
lines, plainly visible under an eighteen diameter hand lens,
though not at all prominent. On July 7 the micropylar area

Op. cit., p. 127.

EGG AND LARVA OF HESPERIA JUBA BDV.

123

showed a small black spot which increased to half the diameter
of the egg by the morning of July 9. The larva emerged some
time during that day and had eaten ail of the free portion of the
egg shell when it was observed at 5:00 p.m.

First Instar: Newly hatched larva 2.3 mm. long, 0.5 mm.
in greatest diameter. Color yellowish white with black setae.
First segment brownish with black cervical shield. First pair
of legs black, second pair distinctly suffused with blackish and
third pair slightly so. It was difficult to make definite observa-
tions of the setae with only a hand lens, but the following may be
quoted from notes made in the field:

On the anal plate there is a marginal row of six setae, the next to
the outermost long (0.3 mm?) and upturned. All others perhaps
not over 0.1 mm. long. Against the pale body they appear dark — it
is certain, at least, that they arise from tiny dark tubercles — but
against the green of a leaf they appear shining and pale, with enlarged
whitish tips.

This suggested glandular hairs, but a lens could not verify the
point. The setal map (fig. 4) shows the arrangement of the
setae of an abdominal segment. It was checked so carefully,
even in bright sunlight, that probably nothing was omitted
which could be seen under the low magnification available.
Diameter of head capsule 0.6 mm.

Second Instar: The first stage larva began its moult on
July 14 and completed it before the morning of July 16. In the
second instar all primary setae excepting the two longest on the
anal plate were either lost or obscured by the sparse coat of
short, dark secondary setae which had appeared. The skin was
yellowish and transparent, the general appearance greenish,
due to the contents of the alimentary canal. The head, first
segment and thoracic legs were extremely dark brown, almost
black; the first segment was marked with a transverse anterior
line, whitish in color. Diameter of head 0.8 mm.

Third Instar: The second moult began on July 22 and, like
the first, was completed before the larva was examined on the
morning of the second day thereafter, viz., July 24. In the

124

A. W. LINDSEY

third instar the appearance of the larva was much as in the
second. Its general color was pale brownish, only slightly
tinged with green. The numerous short brown secondary
setae were scattered on the anterior third of each segment, and
behind this arranged in five or six transverse rows, separated
by shallow wrinkles. The setae appeared to have thick pale
tips, again suggesting glandular structure. Diameter of head
capsule 1.4 mm.

In this stage the larva spun a small cocoon between a blade of
grass and the jar in which it was kept, in preparation for its
moult, which was begun August 5 and completed before 5:00
p.m., August 6.

Fourth Instar: No differences could be noted aside from the
increased size. Diameter of head capsule 2 mm.

On the morning of August 16 the larva had spun another co-
coon with large open meshes, in which it completed its fourth
moult by the morning of August 18. A few days later the ven-
tral surface of the abdomen showed a patch of white fungus, and
when this continued to spread the entire larva was placed in
alcohol.

Fifth Instar: Diameter of head 2.6 mm. The head of the
preserved larva appeared in all ways similar to that of the fourth
instar, as also did the body. Microscopic examination of the
preserved specimen, however, disclosed many details which
could not be observed with a hand lens in the field. The skin
was found to be roughened with numerous stellate prominences,
and the abundant secondary setae proved to be glandular or
sensory as supposed. These setae varied roughly in accordance
with their position on the body. On the back the short form
(fig. 5c) predominated. Ventrad they merged into the form
shown by figure 5b, while on the sides of the thorax the inter-
mediate form (fig. 5a) was observed. With regard to the presence
of primary setae little can be said which is not amply expressed
by the maps in figure 3. The presence of secondary setae of
ordinar}^ form on the ventral surface made it impossible to be
certain that the prominent setae represented were really pri-
mary. The ring-like tubercles, which show their hollow centers

EGG AND LARVA OF HESPERIA JUBA BDV.

125

only under relatively high magnification, are conspicuous struc-
tures. Whether, as suggested by Fracker and as treated here,
they represent primary setae or are an entirely different kind of
organ, remains to be proved. In any case they are probably of
taxonomic value. The first instar map has aided in the inter-
pretation of the fifth instar setae, but is probably incomplete in
the ventral region, due to the low power of the lens used in
making it.

In the first instar the head was light brown with sparse rounded
punctures on the epicranium. The capsules of the remaining
stages, in contrast, were so densely blackish brown that they
could not be examined by transmitted light, and the punctures
covered the entire epicranium and frons, separated by about their
own diameter, and merging into roughened sulci toward the
clypeus. The change in form of the head is well represented
by figures one and two, showing the first and fourth instars. In
the fourth instar a few transparent spots appeared in the epi-
cranium and frons, two, rather long, flanking the frontal suture,
two pairs in the frons, and two larger patches in front of the ocelli.

The setae of the head in the first instar (fig. 1) included a pair
of ultra posteriors and two pairs of adfrontals, all rather promi-
nent, which could not be observed in the later stages. In these,
however, they may possibly have been obscured by the numerous
short curved secondary setae .which were to be found between
the punctures. One ocellar seta likewise was found only in the
first instar, but none of the setae of the middle group of the
labrum could be discovered in this stage, and only one of the
mandibular group.

PLATE X\a

Larva of Hesperia juba Bdv.

Fig. 1 Anterior aspect of head, first instar.

Fig. 2. Anterior aspect of head, fourth instar.

Labels for figures 1 and 2
F Frons
Ec Epicranium

Adfr Adfrontal ridge and suture
L Labrum
M Mandible
Mp Maxillary palpus
Lp Labial palpus
Sp Spinneret
Ant Antenna
I, II, III, IV, V Ocelli

X Ultraposterior seta
Adfi, Adf2 Adfrontal setae
Fa Frontal puncture

Fi Frontal seta
El, E2 Epistomal setae
Oi Ocellar seta
S02 Subocellar seta
Ai Anterior seta

Ml, M2, Ms Median setae of labrum
Lai, La2, Las Setae of labrum

Fig. 3. Setal maps, fifth instar. T ii and T iii, second and third thoracic seg-
ments. A ii and A viii, second and eighth abdominal segments.

Fig. 4. Setal map of abdominal segment, first instar.

Fig. 5. Secondary setae, fifth instar. a. From ventro-lateral region of thoracic
segments, b. From ventral region, c. The most common form, found in lateral
and dorsal regions.

Bulletin Scientific Laboratories Denison University Vol XX

PLATE XVI

3

A. W. LINDSEY

EGG AND LARVA OF HESPERIA JUBA

THE OCCULTATION OF VENUS BY THE MOON ON
JANUARY 13, 1923

P. BIEFELD

An occultation of Venus, like a total eclipse of the Sun, is not
in itself of infrequent occurrence, but for any one place on the
earth’s surface it is extremely rare. The last one visible in this
section of the United States happened early in December of
1878.

At Granville (Swasey Observatory) during the night hours
preceding the event the sky was almost completely covered.
At about 3:00 a.m., however, the sky cleared completely and
Venus shone brilliantly some distance east of the Moon.

Venus was about two weeks past maximum brightness but
still about 130 times as bright as Aldebaran, the follower of the
Pleiades. The Moon was three and one-half days before ^^new,”
showing a slender crescent.

It was a superb sight watching the slow but steady approach
of the two objects. Apparently a collision seemed inevitable;
but only apparently so. The catastrophy was sure to be avoided ;
the Moon being only about a quarter million of miles from us,
while Venus kept at a safe distance of about 47,000,000 miles.
The Moon merely covered up Venus in the line of sight by pass-
ing over her on the celestial sphere.

Quite a number of last year’s and this year’s students of
Astronomy being present, no attempt was made to observe
accurately with the 9-inch the first and second contacts at im-
mersion and emersion, nor were micrometric measures of these
points with reference to the north point attempted. It seemed
more practicable for the benefit of the students to demonstrate
a photographic method for deriving approximately the time of
emersion and duration of occultation from two photographic
exposures before and after occultation respectively and from the

127

128

P. BIEFELD

observation of the time of immersion by the students and myself.
.No attempt was made to get first and second contacts noting
only the time of immersion of the center of the planet.

To have a check on the work Mr. Bannister, a last year’s
student of Advanced Practical Astronomy, computed the occul-
t at ion for Granville. A few statements concerning this are
perhaps of interest.

THEORY OF OCCULTATIONS

An occupation of a fixed star, approximately an occupation
of a planet, may be considered as a special case of an eclipse of
the Sun, imagined so far away that its parallax and diameter
may be taken equal to zero. Then the cone circumscribing the
Sun and Moon in case of a solar eclipse becomes a cylinder in
case of a fixed star or planet. The cylindrical shadow cast by
the planet shining on the Moon is intercepted by the Earth,
or better by a plane passed through the center of the Earth per-
pendicular to a line passing through the center of the planet and
the Moon, and of a linear diameter equal to that of the Moon.
The intersection of the fundamental plane with the plane of the
Earth’s equator plane forms the X-axis of a system of rectangu-
lar coordinates of which the Y-axis lying in the same plane points
to the north, x and y are then the coordinates of the point where
the axis of the shadow pierces the fundamental plane, the center
of the Earth being the origin; x and y being expressed in terms
of the radius of the Earth as unity.

The ‘^elements” for the prediction of the occupation as found
in the American Ephemeris are then as follows:

T, in G. M. T., is the time at which che planet is in geocentric
conjunction in Right Ascension.

H is the geocentric hour angle of the Moon and planet at this
time.

Y is the y-coordinate of the piercing point of the axis of the
shadow cylinder with reference to the fundamental plane at
that moment.

x' and y' are the hourly variation in x and y.

OCCULTATION OF VENUS BY MOON

129

From these elements, together with the position of the place
of the observer and the declination of the planet, the Mean Time
of immersion and emersion of the center of the planet, the angles
which these points make with the north point and the duration
of the occultation may be computed.

OBSERVATIONS AND MEASUREMENTS

1. A photograph was taken before immersion at time Ti (point
I of fig. 3).

2. Immersion was observed at time T2 (point E).

3. A photograph was taken after emersion at time T4, times
Ti, T2, T4 were recorded on the chronograph in Gr. M. T. (Gran-
ville mean time).

4. The two negatives were superimposed and a positive made
of same size with the reproducing camera.

5. Prints were made of this positive for measuring with a mm.
scale to tenths of millimeters. These measurements were after-
w’ards checked with the comparator of the observatory.

Reductions of observations

Ti was found to be 17^^ 35"^ 14.0^ (Gr. M. T.)

T4 was found to be 18 57 06.0 (Gr. M. T.)

T4-T1 was found to be 1 21 52.0 = 34.26 mm.

From this was found 143.38= 1 mm.

T2 was found to be (directly observed immersion) 17^^ 53™ 45®0

T2-T1 was found to be (from measurement of print) 18 13.3

T2 was found to be (from measurement of print) 17 53 27.3

T4-T3 was found to be (from measurement of print) 7 52.9

T4 — Ti — [(T2 — Ti) + [(T4 — T3)] = duration of occultation .... 55 45.8

T4 — (T4 — T3) = T3 (from measurement of print, emersion) 18 49 13.1

Comparison with calculation

Time of immersion

Calculated.

Observed: T2. . .
From print : T2 . .
Time of emersion
Calculated: T3. .
From print T3 . . .

17^55™48^24 (Gr. M. T.)
17 53 45.0

17 53 27.3

18 52 12.12
18 49 13.1

130

P. BIEFELD

Duration of occultation

Calculated. 56 23.88

Measured 55 45.80

Point of immersion from north point calculated 59°59'57"

Point of emersion from north point calculated 330 29 52

Measurements with scale. 1 mm. = 145® 3

Measurements with comparator. . .’ 1 mm. = 143. 38

PLATE XVII.

Fig. 1. Photograph taken at time Ti.

Fig. 2. Photograph taken at time T2.

Fig. 3. Diagram of two photographs superimposed.

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE XVI r

S

Fig. 3

P. BIEFELD

OCCULTATION OF VENUS BY MOON

»'V'

A BOTANICAL SURVEY OF THE CAMPUS OF
DENISON UNIVERSITY!

DWIGHT MUNSON MOORE
INTRODUCTION

General location. The campus of Denison University is one
of the most attractive spots in the state of Ohio. The greater
part of it is on a hill at the northern margin of the village of
Granville, situated near the center of Licking County, close to
the geographic center of the state. Recent additions to the
campus have increased its area to approximately 350 acres.
Of this, Shepardson College occupies about one acre, Granville
College about fifty acres, and the remainder composes Deeds
Field, a great recreation and athletic field, and the College
Farm.

Scope of this paper. The present study is limited to the phaner-
ogams of that part of the campus bounded by Burg street on the
west. College street on the south. Mulberry street and its north-
ward extension on the east, and the northern edge of the College
woods, hereafter called the North Woods, on the north. It is
hoped that the paper may later be supplemented with a study
of the rest of the campus.

Geology and physiography . The region is near the western
edge of the Allegheny Plateau, within the zone of transition
between the maturely dissected upland occupying the greater
part of southeastern Ohio and the undulating lowland of cen-
tral western Ohio. One of many hills of a rolling upland, inter-
sected by streams, has been chosen for the campus. Its summit
rises slightly above 1100 feet in altitude, and overlooks the broad
flat-floored valley of Raccoon Creek which flows eastward along
the southern foot of the hill at an elevation of about 900 feet

^ Contribution from the Botanical Laboratory of Denison University, No. XIII.

131

132

DWIGHT MUNSON MOORE

above the sea. The north slope of College Hill is much shorter
and more abrupt than the principal south slope.

The rocks underlying the region are indicated in the accom-
panying diagram (fig. 1). All belong to the Waverly Series^
of Mississippian age^ and are grouped by geologists into two
formations^ the Logan and Cuyahoga, each comprising several
members. The top of College Hill is composed of a rather
coarse sandy shale or sandstone, the Allensville member of the
Logan formation. Beneath this, and outcropping near the west
margin of the campus at the ^ ^Biological Book’ is the Byer sand-

Fig. 1. Diagram Showing Geologic Structure of College Hill

stone, a freestone which has been quarried at several places on
the higher slopes of the hill. The Berne conglomerate beneath
the Byer marks the division between the two formations, named
above. It is a rather inconspicuous bed, 6 to 18 inches thick,
composed of clean quartz pebbles in a sandy matrix. The Black
Hand and Raccoon members of the Cuyahoga are sandstones
interspersed with sandy shales of quite variable thickness and
composition.

All of these on weathering produce a rather loose and more
or less sandy soil which is found on the greater part of the cam-
pus. Where shales predominate, however, there is a stiff er clay

SURVEY OF CAMPUS OF DENISON UNIVERSITY

133

soil which in places packs hard and is unfavorable for the growth
of many plants. The entire region has been covered at least
twice by ice sheets which left a thin and scattered deposit of
glacial drift. In consequence the surface is quite gravelly at
many places.

Climatology. The data for this topic have been taken more or
less completely from a report compiled by J. Warren Smith,
covering the climate and weather in south central Ohio, in the
general summary of climatological data for the United States.
No records have been made in this area by the writer, but the
data for Columbus, 28 miles distant, extend from 1878 and these
have been used.

The monthly mean temperatures in degrees Fahrenheit and
and the average monthly rainfall in inches at Columbus are as
follows :

MONTHLY MEAN
TEMPERATUKES
(31 YEARS OP
records)

AVERAGE

MONTHLY RAINFALL
(30 YEARS OF
records)

January

28.9

2.97

February

30.1

3.01

March.

39.6

3.49

April

51.1

2.84

May

62.5

3.80

June

71.0

3.41

July

75.2

3.65

August

72.7

3.21

September.

66.9

2.41

October

54.7

2.32

November

41.8

2.91

December.

32.7

2.66

Annual

52.2

36.68

Growing season

66.6

The absolute extremes of temperature for the central part of
Ohio are 108° and —34°. These are important because of their
possible effect in limiting the growth of vegetation, tending to
control the northern limits of many species.

Fig. 2. The North Wood in Early Spring, Showing Nature of Undergrowth

ECOLOGY

The natural growth of vegetation has been changed for orna-
mental purposes, except that of the north hillside, which is
almost a virgin forest. The area thus may be divided into
wooded areas and open tracts. Among the first there are two:
the North or College Wood (I) and the West Wood (II). Of
the open tracts four may be distinguished, viz.: the West cam-
pus (III), South hillside (IV), East campus (V) including south-
east hillside, and the central campus (VI).

DWIGHT MUNSON MOORE

The average date of the last killing frost in spring is April
30, of the first killing frost in the autumn, Oct. 2. The average
growing season is therefore about 155 days in length. However,
the minimum growing season is about 1 10 days. ^Trecipita-
tion is quite uniform over the whole section (in which our area
is located) and averages about 38 inches per year.^’ ^Tn general
there is the greatest average rainfall in June and July and the
least in October.”

SURVEY OF CAMPUS OF DENISON UNIVERSITY

135

Fig. 3. The Flooe of College Wood in Spring, Showing Hydrophylltjm,
Galium and the Dicentras

and pubescens. All of these are quite low forms which must
complete their short period of photosynthetic work before other
larger plants overshade them.

In May there is a greater profusion of Hydrophyllum and
Chelidonium with Galium aparine pushing upward. Late in
May and early June these have mostly given way to Impatiens
hiflora and various other scattered taller forms.

Later in the summer these forms have given place to various
Asters, especially Aster cordifoUus, and to Eupatorium urticae-
folium.

The wooded areas

I. The College Wood is a typical mesophytic wood, princi-
pally of beech, maple, elm, ash, and only a few oak trees. This
might be termed a moist wood. The forest floor presents an
excellent example of seasonal plant succession. In April the
floor is almost entirely covered with the two Dicentras, and
Dentaria lacinata, with a generous sprinkling of Viola cucullata

136

DWIGHT MUNSON MOORE

This wood presents a good illustration of forest succession.
The majority of the trees are beech and maple, while the oaks and
chestnut appear to be among the oldest. But among the young
trees coming on there are almost no oaks, chestnut, or hickory
while there is an abundance of maples, beech, elms, and wild
cherry. This clearly shows that the oaks, hickories and chest-

Fig. 4. The North Wood, with a Dense Growth of Hydrophyllum

nuts are losing ground and will all disappear within the coming
generation, giving place entirely to the others which are domi-
nant among the seedlings.

Recently an effort has been made to save some of the older
beeches which have become hollow, by the application of tree
surgery. This seems to have been successful in several cases.

Another recent introduction in this wood is the building of a
Tjreek temple which serves as the background for the stage of
an outdoor theater in the center of the wood. Naturally the
use of the wood for this purpose will have a serious effect upon

SURVEY OF CAMPUS OF DENISON UNIVERSITY

137

the plant forms which happen to be in their period of flower
at the time the amphitheater is used. But this may not be great
if its use is not carried too far.

II. In the West Wood, the trees are much the same, with
the beech most abundant then the sugar maple, elms, black
walnut, and wild cherry making up the most of the remainder.
Here is noticed, even more than in the North Wood, that it is
the beech and maple that make up the majority of the young

Fig. 5. The West Wood

trees. Thus this wood will continue to be a beech-maple associa-
tion through the next generation.

The soil here is much drier, due probably to the southern
exposure, a more open wood, and the fact that the soil is thinner
over the underlying strata of rock.

Owing to the moisture conditions, the ground flora is more
limited than in the North Wood. Here are found principally
Sanguinaria canadensis, Podophyllum peltatum, Clatonia vir-
ginica; various species of Geum, Galium, Desmodim, and Carex;

138

DWIGHT MUNSON MOORE

also Bidens hipinnata, Ruhus allegheniensis, and Solidago caesia.
It is quite interesting to note the entire absence here of the
Hydrophyllum and the Dicentras which are so profuse in the
North Wood.

III. Of the open tracts the west section is perhaps the driest.
.There are several trees scattered over the larger part of it, and
west of the library these are numerous enough to make it quite
shaded. The prominant trees are Fagus grandifolia, Fraxinus
americana, Ulmus americana and fulva, and Acer saccharum.
Of the herbaceous plants the most prominant are:

Andropogon virginicus Dactylis glomerata

Danthonia spicata Erigeron annuus

Poa compressa Erigeron philadelphicus

Poa pratensis Capsella Bursa-pastoris

Juncus tenuis

IV. The south hillside has the flora of an open meadow and
includes several grasses and others:

Achillea millefolium
Ambrosia artemisiifolia
Asclepias syriaca
Daucus carota
Dactylis glomerata
Erigeron annuus
Erigeron philadelphicus
Galium aparine
Galium concinnum
Hypericum mutilum

Lactuca scariola
Poa pratensis
Ranunculus abortivus
Rumex acetosella
Rumex crispus
Rumex obtusifolius
Saponaria officinalis
Solidago rugosa
Solidago serotina

However at the foot of the hill, a line of Spruce trees casts such
a shade that there are but a few forms, especially Galium aparine,
Geum vernum, Menispermum canadense, P seder a quinquefolia,
Ranunculus abortivus.

But taken as a whole the south hillside has the widest variety
of any group studied. This appears to be due to the abundant
sunlight and rather moist soil, brought about by a springy’’
condition of the underlying rock strata. Also the fact that
this receives very little attention during the year — it being
mowed not more than twice in the twelve-month^ — permits
the introduction, growth and fruiting of many new and varied
forms.

SURVEY OF CAMPUS OF DENISON UNIVERSITY

139

Among the trees that may be mentioned are only such as
have been planted for ornamental purposes. There are found
here the following: Scotch Pine^ Norway Spruces, Kentucky
Coffee Tree, Norway and Silver Maples, Japan Maple, Osage
Orange.

Fig. 6. The Slope op the Central Campus from the Hilltop Toward the South Plaza

V. The east hillside and campus are quite similar to the
south hillside in most respects. The slope is probably more
abrupt at first, becoming more nearly level lower down.

The trees that have been planted on this slope are :

Alnus glutinosa
Betula Alba
Chionanthus virginica
Corylus avelana

Betula populifolia
Cercis canadensis
Moms rubra
Platanus occidentalis

140

DWIGHT MUNSON MOORE

VI. The central campus has the constant attention of a care-
taker, and for the greater part is carefully mowed as often as
once a week. This practice has reduced the number of forms
to only those which are naturally low or can adjust themselves
to these conditions. Here we find principally:

Agrostis alba
Cerastium vulgatum
Plantago lanceolatus
Plantago major
Poa pratensis
Prunella vulgaris

Stellaria media
Taraxacum officinale
Veronica arvensis
Veronica serpyllifolia

In this area also have been planted such shrubs and trees as

Acer rubrum Crataegus Crus-galli

Acer saccharum Ulmus americana

Aralia spinosa Ulmus fulva

Artificial grouping has been carried out around all the build-
ings and at the principal entrances. The accompanying views
of the east entrance show the masses of Kerria, Rosa, Rhodo-
typos, Forsythia and Symphoricarpos.

Around the buildings are found a number of species of Deut-
zia, and Spirea, as well as Berberis, Forsythia, Kerria, Lonicera,
Philadelphus, Symphoricarpos. These introduced species are
bunched and so selected that there are some of them in flower
from the opening of the Forsythia in April through the roses
in the summer and leaving the attractive white berries of
Symphorocarpos in the fall.

FLORA

In making the study of the flora of the campus, the writer
found it necessary to start from the beginning as there was
absolutely no record of any plants of this particular region.

No effort has been made to make a complete collection of
the various forms found, but when any were found which the
herbarium of the University did not contain, they were added
to it.

SURVEY OF CAMPUS OF DENISON UNIVERSITY

141

Verification of the identification of the plants given below in
the list has been made by reference to and comparison with the
herbarium of the department of Botany of Denison University.

The nomenclature used is that of Gray^s New Manual of
Botany, 7th Edition^ except in the case of the exotics which are

Fig. 7. The Campus on the Hill

not included in the Manual, In these cases Gray’s Field,
Forest and Garden Botany and Bailey’s Cyclopedia of American
Horticulture have been used. Britton and Brown’s Illustrated
Flora of the Northern States and Canada has been freely used
in the identification of the plants.

The Flora as follows is listed in the order given in the Check
list of the plants found in Gray’s Manual, published by the Gray

142

DWIGHT MUNSON MOORE

Herbarium of Harvard University. Such plants as are quite
evidently not growing in their natural habitat or have been
set out on the campus are printed in italics.

Gymnospermae

Ginkgoaceae — Ginko Family.

Ginkgo hiloha L. Maiden-hair tree. Back of Marsh Hall.
Pinaceae — Pine Family.

Abies concolor Lindl. White fir. IV.

Juniperus Virginiana L. Red cedar. IV, and a few scat-
tered seedlings.

Picea ahies (L.) Karst. Norway spruce. H, IV, V.

Finns strohus L. White pine. One small tree behind Cleve-
land Hall.

Finns sylvestris L. Scotch Pine. I, IV.

Taxodinm distichnm (L.) Richard. Bald cypress. Behind
Marsh Hall.

Thnja occidentalis L. Arbor vitae. White cedar. Near
Cleveland Hall and near entrances.

Angiospermae

Graminae — Grass Family.

Agropyron repens (L.) Beauv. Couch grass. HI.

Agrostis alba L. Red top. General in HI, IV, V, VI.
Andropogon virginicus L. Virginia beardgrass. HI, V.
Bromus ciliatus L. Fringed brome-grass. I.

Dactylis glomerata L. Orchard grass. HI, IV, V.

Danthonia spicata (L.) Beauv. Wild oat-grass. HI, IV, V.
Digitaria sanguinalis (L.) Scop. Crab grass. IV.

Eragrostis megastachya (Koeler) Link. Stink-grass. V.
Eragrostis pilosa (L.) Beauv. (Jones.)

Festuca nutans Speng. Nodding fescue grass. I.

Koeleria cristata (L.) Pers. Koleria. VI.

Lolium perenne L. Darnel. IV.

Muhlenbergia Schreberi J. F. Gmel. Nimble-Wili; Drop-

seed grass. I.

Panicum capillare L. Witch grass. IV.

Panicum dichotomum L. Forked panic-grass. HI, IV.
Phleum pratense L. Timoth}^ HI, IV, V.

Poa annua L. Low speargrass. HI, IV, V.

Poa compressa L. Wire grass; English blue-grass. HI,
IV, V.

SURVEY OF CAMPUS OF DENISON UNIVERSITY

143

Poa pratensis L. Kentucky blue-grass. Ill, IV, V.

Secale cereale L. Rye. III.

Setaria glauca (L.) Beauv. Ill, IV.

Setaria viridis (L.) Beauv. Ill, IV, V.

Triticum sativum L. Wheat. III.

Cyperaceae — Sedge Family.

Carex cephaloidea Dewey. Thin leaved sedge. IV.

Carex digitalis Willd. Slender wood sedge. II.

Carex granularis Muhl. Meadow sedge. Ill, IV.

Carex laxifiora Lam. Loose-flowered sedge. I, 11.

Carex laxiflora var. latifolia Boott. White bear sedge.
I, 11.

Carex plantaginea Lam . ( J ones . )

Carex rosea Schkuhr. Yellow sedge. 11.

Carex Shortiana Dewey. Short’s sedge. Edge of I.

Carex straminaea Willd. Straw sedge. IV,

Carex triceps Michx. Hirsute sedge. IV.

Carex vulpinoidea Michx. Fox sedge. IV.

Araceae — Arum F amily .

Arisaema triphyllum (L.) Schott. Indian turnip. I, II.
Juncaceae — Rush Family.

Juncus tenuis Willd. Slender yard rush. III.

Lilliaceae — Lily Family.

Asparagus ofScinalis L. Garden asparagus. Ill, IV.
Medeola virginiana L. Indian cucumber-root. 11.
Ornithogalum umbellatum L. Star of Bethlehem. V.
Polygonatum biflorum (Walt) Ell. Small Solomon’s Seal. 11.
Polygonatum commutatum (R & S) Dietr. Great Solomon’s
seal. II.

Smilacina racemosa (L.) Desf. False spikenard. 11.

Smilax herbacea L. Carrion flower. I.

Smilax rotundifolia L. Greenbrier. I, 11.

TuUpa gesneriana L. Common tulip. Near Marsh Hall.
Uvularia perfoliata L. Meal}^ bell wort. I.

Yucca filimentosa L. Yucca. IV.

Dioscoreaceae — Yam Family.

Dioscorea villosa. Wild Yam-root. I.

Iridaceae — ^Iris Family.

Sisyrinchium gramineum Curtis. Blue-eyed grass.

144

DWIGHT MUNSON MOORE

Orchidaceae — Orchid Family.

Orchis spectabilis L. Showy orchid. I.

Spiranthes gracilis (Bigel) Beck. (Jones.)

Salicaceae —Willow Family.

Populus alba L. Silver leaved poplar. III.

Populus deltoides Marsh. Cotton-wood. V.

Salix discolor Muhl. Pussy willow. Talbot Hall.
Juglandaceae — Walnut Family.

Carya cordiformis (Wang) I\. Koch. Bitternut. I. II.
Carya ovata (Mill) K. Koch. Shellbark hickory. I, II.
Juglans cinerea L. Butternut; White walnut. II.

Juglans nigra L. Black walnut. I, II, III, V.

Betulaceae — Birch Family.

Alnus glutinosa L. European alder. V.

Betula alba L. Cut-leaved weeping birch. V.

Betula populifoUa Marsh. White birch. V.

Corylus avellana L. European hazelnut. V.

Ostrya virginiana (Mill) K. Koch. American hop-hornbeam. IV.
Fagaceae — Beech Family.

Castanea dentata (Marsh) Borkh. Chestnut. I, II.

Fagus grandifolia Ehrh. Beech. I, II, III.

Quercus alba L. White Oak. I, II.

Quercus bicolor Willd. Swamp white oak. III.

Quercus coccinea Muench. Scarlet oak. II, III.

Quercus macrocarpa Michx. Burr oak. III.

Quercus pedunculata Ehrh. English oak. III.

Quercus Prinus L. Chestnut oak. III.

Quercus rubra L. Bed oak. III.

Urticaceae — Nettle Family.

Celtis occidentalis L. Hackberry. I, II, V.

Humulus lupulus L. Hop vine. IV, V.

Laportea canadensis (L.) Gaud. Wood nettle. I.

Madura pomifera (Raf.) Schneider. Osage orange. IV.
Moms rubra L. Red mulberry. I, V, VI.

Parietaria pennsylvanica Muhl. Pennsylvania pellitory. I, II.
Pilea pumila (L.) Gra}^ Rich weed; clear weed. I, II.
Ulmus americana L. White elm. I, II, III, IV, V, VI.
Ulmus fulva Michx. Red elm. I, II, VI.

Polygonaceae — Buckwheat Family.

Polygonum aviculare L. Knot-grass; door weed. IV, V, VI.

SURVEY OF CAMPUS OF DENISON UNIVERSITY

145

Polygonum Convolvulus L. Black bindweed. IV, V
Polygonum Persicaria L. Lady’s thumb. I.

Rumex acetosella L. Sheep sorrel. Ill, IV, V.

Rumex crispus L. Curly dock. Ill, IV, V.

Rumex obtusifolius L. Yellow dock. Ill, IV, V.
Phytolaccaceae — Pokeweed Family.

Phytolacca decandra L. Pokeweed. V.

Illecebraceae — Knotwort Family.

Anychia canadensis (L.) B.S.P. Forked chickweed. I, II.
Caryophyllaceae — Pink Family.

Agrostemma Githago L. Corn cockle. IV.

Arenaria serpyllifolia L. Thyme-leaved sandwort. V.
Cerastium vulgatum L. Mouse-ear chickweed. General.
Saponaria ociffinalis L. Bouncing Bet. IV.

Stellaria media (L.) Cyrill. Common chickweed. General.
Portulacaceae — Purslane Family.

Claytonia virginica L. Spring beauty. II, III, VI.
Banunculaceae — Crowfoot Family.

Actaea alba (L.) Mill. White baneberry. I.

Anemonella thalictroides (L.) Spach. Wind flower. I, II.
Cimicifuga racemosa (L.) Nutt. Black cohosh. I.

Clematis virginiana L. Virgin’s bower. Ill, IV.

Hepatica triloba Chaix. Round lobed hepatica. I.
Ranunculus abortivus L. Small flowered crowfoot. General.
Ranunculus acris L. Tall crowfoot. One plant in 1914. VI.
Ranunculus repens L. Creeping buttercup. I.

Magnoliaceae — Magnolia Family.

Liriodendron tulipifera L. Tulip tree. II.

Calycanthaceae^ — Calycanthus F amily .

Calycanthus floridus L. Strawberry shrub. IV.

Anonaceae — Custard Apple Family.

Asimina triloba Dunal. Common Papaw. I.
Menispermaceae — Moonseed Family.

Menispermum canadense L. Moonseed vine. II, IV.
Berberidaceae— Barberry Family.

Berberis aquifoUum Fursh. Alahonia. East end of Talbot Hall.
Berheris vulgaris L. European barberry. V.

Berheris Thunbergii DC. Japanese barberry. Entrances.
Caulophyllum thalictroides (L.) Michx. Blue cohosh. I.
Podophyllum peltatum L. Mayapple. I, II.

146

DWIGHT MUNSON MOORE

Lauraceae — Laurel Family.

Benzoin aestivale (L.) Nees. Spicebush. I,

Papaveraceae — Poppy 'Family.

Chelidonium majus L. Celandine. I.

Sanguinaria canadensis L. Bloodroot. 1^ II.

Fumariaceae — Fumitory Family.

Dicentra canadensis (Goldie) Walp. Squirrel corn. I.
Dicentra Cucullaria (L.) Dernh. Dutchman’s breeches. I.
Cruiferae — Mustard Family.

Barbarea stricta Andrz. Winter cress. II, III.

Barbarea vulgaris R Br. Yellow rocket. I,

Capsella Bursa-pastoris (L.) Medic. Shepherds’ purse.
General.

Cardamine bulbosa (Schreb.) B. S. P. Spring cress. I.
Dentaria lacinata Muhl. Toothwort. I.

Draba verna L. Whitlow grass. VI.

Lepidium virginicum L, Wild peppergrass. 1, II, III, IV,
V, VI.

Sisymbrium officinale (L.) Scop. Hedge mustard. Ill,
IV, V.

Crassulaceae —Orpine Family.

Sedum ternatum Michx. Stonecrop. I.

Saxifragaceae^ — Saxifrage Family.

Deutzia scabra Thunb. Deutzia. Around buildings.
Philadelphus coronarius L. Mock orange; syringa. Same.
Ribes Cynosbati L. Wild gooseberry. I.

Saxifraga virginiensis Michx. Early saxifrage. II.
Platanaceae — Plane tree Family.

Platanus occidentalis L. Sycamore tree. V.

Rosaceae — Rose Family.

Agrimonia gryposepala Wallr. Tall hairy agrimony. II.
Crataegus Crus-galU L. Cockspur thorn. VI.

Crataegus punctata Jacq. Large-fruited thorn. II.

Fragaria virginiana Duchesne. Strawberry. II, IV, V.

Geum canadense Jacq. White avens. II.

Geum vernum (Raf.) T & G. Spring avens. I, II, HI.
Kerria Japonica DC. Japanese Rose. Entrances.

Potentilla argentea L. Silvery cinquefoil. III.

Potentilla canadensis L. Fivefinger. II, III, IV.

SURVEY OF CAMPUS OF DENISON UNIVERSITY

147

Prunus americana Marsh. Wild plum. II.

Prunus avium L. Sweet cherry. IV.

Prunus serotina Ehrh. Wild black cherry. I, II, III, IV, V.
Pyrus Aucuparia Ehrh. European mountain ash. III.

Pyrus communis L. Pear. III.

Pyrus Japonica Thunb. Japanese Quince. VI.

Pyrus mains L. Apple. Ill, IV, V.

Rhodotypos kerrioides Sieb. False Kerria. Entrances.

Rosa multiflora Thunb. Rambler rose. Entrances and V.
Rosa rubiginosa L. Sweetbrier. V.

Rosa Rugosa Thunb. Entrances.

Rosa setigera Michx. Prairie rose, Entrances.

Rosa wichuraiana Crepin. Memorial rose. Entrances.
Rubus allegheniensis Porter. Blackberry. I, II, III, V.
Rubus occidentalis L. Black raspberry. I, II, III, V.

Rubus odoratus L. Purple-flowering raspberry. East en-
trance.

Rubus villosus Ait. Dewberry. III.

Spirea bumalda Burvenich; Anthony Waterer. Crimson
Spivea. Marsh.

Spirea Douglassi Hook. Douglas’ Meadowsweet. Near-
buildings.

Spirea Thunbergii Sieb. Snow Garland. Marsh Hall.

Spirea Van Houtei Zabel. Bridal wreath. Abundant along
drives.

Leguminosae — Pulse E amily .

Amorpha fruticosa L. False indigo. V.

Amphicarpa monoica (L.) Ell. Hog peanut. I.

Cercis canadensis L. Redbud. V.

Cladrastis lutea (Michx. f.) Koch. Yellow wood. I.
Desmodium canescens (L.) DC. Hoary tick-trefoil. I, II,
III, IV, V.

Desmodium grandiflorum (Walt.) DC. Pointed-leaved tick-
trefoil. I, II.

Gleditsia triacanthos L. Honey locust. II, III.

Gymnocladus dioica (L.) Koch. Kentucky coffee tree.* I, IV.
Melilotus alba Desr. White sweet clover. Ill, IV, V.
Robinia Pseudo-Acacia L. Black locust. II, V.

Trifolium hybridum L. Alsike clover. Ill, IV, V.

Trifolium pratense L. Red clover. II, III, IV, V.

148

DWIGHT MUNSON MOORE

Trifolium procumbens L. Yellow hop-clover. Ill, IV, V, VI.
Trifolium repens L. White clover. General in the open.
Oxalidaceae — Wood sorrel Family.

Oxalis stricta L. Yellow wood sorrel. General.

Oxalis violacea L. Violet wood sorrel. I.

Geraniaceae — Geranium Family.

Geranium maculatum L. CranesbilL I, II.

Euphorbiaceae — Spurge Family.

Acalypha virginica L. Three-seeded mercury. General in
shade.

Euphorbia maculata L. Spotted spurge. South hill.
Anacardiace^e — Cashew Family.

Rhus copallina L. Dwarf sumac. IV.

Rhus cotinus L. Smoke tree. V, VI.

Rhus glabra L. Smooth sumac. II, III.

Rhus Toxicodendron L. Poison ivy. I, II, III, IV.
Celastraceac' — Staff tree Family.

Celastrus scandens L. Bittersweet, Wax work. I, II, III.
Evonymus atropurpureus Jacq. Wahoo._ II, VI.

Evonymus radicans Sieb. Jap. spindle bush. Entrance and
south plaza.

Staphyleacea^f*— Bladdernut F amily .

Staphylea trifolia L. American bladdernut. I.

Aceraceae — Maple Family.

Acer Ginnala Max. Tartarian maple. VI.

Acer negundo L. Box elder. II, IV, V.

Acer palmatum Thunb. Japanese Maple. IV.

Acer palmatum var. ornatum, Carr. Cut-leaved Japanese
Maple. IV.

Acer palmatum var. reticulatum, Andre. IV.

Acer platanoides L. Norway maple. Two forms. IV.

Acer rubrum L. Red maple. VI.

Acer saccharinum L. Silver maple. Ill, IV, VI,

Acer saccharum Marsh. Sugar maple. I, II, III, VI.
Sapindaceae — Soapberry Family.

‘ Aesculus glabra Willd. Ohio buckeye. I.

Aesculus Hippocastanum L. Horse chestnut, V.
Balsaminaceae — Touch-me-not F amily.

Impatiens biflora Walt. Jewel weed. I.

Impatiens pallida Nutt. Pale touch-me-not. I.

SURVEY OF CAMPUS OF DENISON UNIVERSITY

149

Rhamnaceae — Buckthorn Family.

Rhamnus cathartica L. Common buckthorn. V.

Vitaceae — Vine Family.

Ampelopsis tricuspidata Sieb. & Zucc. Boston ivy. On
buildings. ,

Psedera quinquefolia (L.) Greene. Woodbine ivy. I,
II, VI.

Vitis vulpina L. Frost grape. I, II.

Tiliaceae — Linden Family.

Tilia americana L. Basswood; Linden. I, II.

Tilia heterophylla Vent. White basswood. III.

Malvaceae — Mallow Family.

Althaea rosea Cav. Hollyhock. IV.

Hibiscus syriacus L. Shrubby althea. VI.

Malva rotundifolia L. Common mallow, Cheeses. Ill, IV,
V, VI.

Hypericaceae — St. John’s-wort Family.

Hypericum punctatum Lam. Spotted St. John’s-wort. II,
IV, V.

H5rpericum mutilum L. Small flowered St. John’s-wort.
IV, V.

Violaceae — Violet Family.

Viola papilionacea Pursh. Common blue violet. General.
Viola pubescens Ait. Downy yellow violet. I, II.

Viola rostrata Pursh. Long-spurred violet. I.

Elaeagnaceae — Oleaster Family.

Elaeagnus argentea Pursh. Silver berry. V.

Elaeagnus angustifolius (L.) var. Spinosa, Dipp. Oleaster.
East entrance.

Onagraceae — Evening Primrose Family.

Circaea lutetiana L. Enchanter’s nightshade. I, II.
Oenothera biennis L. Common evening primrose. Ill,
IV, V.

Araliaceae — Ginseng Family.

Aralia racemosa L. Spikenard. I.

Aralia spinosa L. Hercules’ club. VI.

Hedera helix L. English ivy. Marsh Hall.

Panax quinquefoliam L. Ginseng. Found in I as late as
1914.

150

DWIGHT MUNSON MOORE

Umbelliferae — Parsley Family.

Cryptotaenia canadensis (L.) DC. Honewort. I, II.
Daucus Carota L. Wild carrot. General in the open.
Osmorhiza Claytoni (Michx.) Clarke. Sweet cicely. I.
Sanicula canadensis L. Short-styled snakeroot. I, II.
Sanicula trifoliata Bicknell. Large fruited snakeroot. I.
Cornaceae — Dogwood Family.

Cornus alba, var. siherica.

Cornus florida L. Flowering dogwood. I, II, V.

Cornus Mas L. Cornelian cherry. V.

Cornus stolonifera, Michx. Red-osier dogwood. V.

Nyssa sylvatica Marsh. Sour gum. I, II.

Ericaceae^ — Heath Family.

Monotropa uniflora L. Indian pipe. I.

Primulaceae^ — Primrose Family.

Lysimachia quadrifolia L. Whorled loosestrife. II.

Oleaceae^ — Olive Family.

Chionanthus virginica L. Fringe tree. V.

Forsythia suspensa Vahl. Goldenbell. East entrance.
Forsythia viridissima Linde. Goldenbell. East entrance.
Fraxinus americana L. White ash. I, II, III.

Fraxinus quadrangulata Michx. Blue ash. I.

Syringa vulgaris L. Common lilac. Near buildings.
Apocynaceae — Dogbane Family.

Vinca minor L. Periwinkle. I and on open hillsides.
Asclepiadaceae — Milkweed F amily .

Asclepias purpurascens L. Purple milkweed. IV.

Asclepias syriaca L. Common milkweed. Ill, IV, V.
Asclepias tuberosa L. Butterfly weed. (Jones.)
Hydrophyllaceae — W aterleaf F amily.

Hydrophyllum appendiculatum Michx. Appendaged water-
leaf. I.

Hydrophyllum macrophyllum Nutt. Large-leaved water-
leaf. I.

Boraginaceae — ^Borage F amily.

Lithospermum arvense L. Corn gromwelL III.

Labiatae — Mint Family.

Agastache nepetoides (L.) Ktze. Giant hysop. I.

Agastache scrophulariaefolia (Willd.) Ktze. Figwort hysop. I.
Hedeoma pulegioides (L.) Pers. American pennyroyal.
II, HI.

SURVEY OF CAMPUS OF DENISON UNIVERSITY

151

Lamium amplexicaule L. Henbit dead-nettle. III.

Lamium purpureum L. Eed deadnettle. II, III.

Leonurus Cardiaca L. Catnip. IV, VI.

Prunella vulgaris L. Self-heal. General.

Solanaceae— Nightshade Family.

Physalis pubescens (L.). Low hairy ground-cherry. IV.
Physalis Virginia Mill. Virginia ground-cherry. IV.
Solanum Dulcamara L. Bittersweet. I, V.

Solanum nigrum L. Black nightshade. IV.

Scrophulariaceae — Figwort F amily.

Linaria vulgaris Hill. Butter and eggs. Ill, IV, V.
Verbascum Thapsus L. Mullein. Ill, IV, V.

Veronica arvensis L. Corn speedwell. General in the open.
Veronica peregrina L. Purslane-leaved veronica. General.
Veronica serpyllifolia L. Thyme-leaved veronica. General.
Orobanchaceae — Broom-rape Family.

Epifagus virginiana (L.) Bart. Beechdrops. I, II.
Bignoniaceae — Bignonia F amily.

Catalpa hignonioides Walt. Catalpa. V, VI.

Tecoma radicans (L.) Juss. Trumpet creeper. IV, VI.
Phrymaceae — Lopseed Family.

Phryma Leptostachya L. Lopseed. I.

Plantaginaceae — Plantain Family.

Plantago lanceolata L. Ribwort; English plantain. General.
Plantago major L. Greater plantain. General.

Plantago Rugellii Dene. Rugel’s Plantain. General.
Rubinaceae — Madder Family.

Galium Aparine L. Cleavers. General in shaded places.
Galium circaezans Michx. Wild licorice. II, III.

Galium concinnum T & G. Shining bedstraw. 11.

Galium triflorum Michx. Fragrant bedstraw. I, 11.
Houstonia caerulea L. Bluets; Innocence. III.

Houstonia longifolia Gaertn. Long-leaved houstonia. III.
Caprifoliaceae — Honeysuckle Family.

Diervilla grandiflora S & Z. Weigelia. Near buildings.
Lonicera japonica Thunb. Japanese honeysuckle. Ill, IV, V.
Lonicera sempervirens L. Coral honeysuckle. II.

Lonicera tartarica L. Tartarian honeysuckle. Entrances.
Lonicera Xylosteum L. European fly honeysuckle. V.
Sambucus canadensis L. American elder. II, IV, VI.

152

DWIGHT MUNSON MOORE

Samhucus nigra L. European elder. East plaza.
Symphoricarpos orbiculatus Moench. Coralberry. Entrances.
Symphoricarpos racemosus Michx. Snowberry. Entrances.

Viburnum prunifolium L. Black haw. II.

V alerianaceae — V alerian F amily .

Valerianella radiata (L.) Dufr. Beaked corn salad. IV.
Dipsacaceae — Teasel Family.

Dipsacus sylvestris Huds. Teasel. III.

Campanulaceae — Blue bell F amily.

Specularia perfoliata (L.) A. DC. Venus’s Looking-glass.
II, III.

Lobeliaceae — Lobelia Family.

Lobelia inflata L. Indian tobacco. Ill, IV.

Lobelia spicata Lam. Pale spiked lobelia. II.

Compositae — Composite Family.

Achillea Millefolium L. Yarrow. General in the open.
Ambrosia artemisiifolia L. Common ragweed. General.
Ambrosia trifida L. Tall ragweed, II, IV, V.

Antennaria plantaginifolia (L.) Richards. Piantain-leaved
everlasting. III.

Anthemis Cotula L. May weed. IV.

Arctium Lappa L. Burdock. Ill, IV, V, VI.

Aster cordifolius L. Blue wood aster. Common.

Aster ericoides L. White heath aster. Ill, IV, V.

Aster novae anglicae L. New England aster. III.

Bidens bipinnata L. Spanish needles. II.

Bidens frondosa L. Beggar-ticks. General.

Chrysanthemum Leucanthemum L. White daisy. III.
Circium lanceolatum Hill. Common bull thistle. IV, V.
Erigeron annuus (L.) Pers. Sweet scabius. General in the
open.

Erigeron canadensis L. Horseweed. General.

Erigeron Philadelphicus L. Philadelphia fleabane. General.
Eupatorium urticaefolium Reichard. White snakeroot. 1.
Gnaphalium polycephalum Michx. Sweet everlasting. Ill,
IV.

Hieracium venosum L. Rattlesnake weed, II.

Lactuca canadensis L. Wild lettuce. Ill, IV, V.

Lactuca scariola L. Prickly lettuce. Ill, IV, V.

Prenanthes altissima L. Tall white lettuce. I, II.

SURVEY OF CAMPUS OF DENISON UNIVERSITY

153

Senecio aureus L. Golden ragwort. II, III.

Solidago caesia L. Wreath goldenrod. II, I.

Solidago juncea Ait. Early goldenrod. III.

Solidago rugosa Mill. Tall hairy goldenrod. Ill, IV.
Solidago serotina Ait. Late goldenrod. Ill, IV.

Taraxacum officinale Weber. Dandelion. General.
Vemonia altissima Nutt. Ironweed. Ill, IV, V.

Summary :

Families 74.

Genera 210
Species 321

BIBLIOGRAPHY

Bailey, L. H.: Cyclopedia on American Horticulture.

Britton and Brown: Illustrated Flora of the Northern States and Canada.
Carney, Frank: Glaciation in Ohio.

Gray, Asa: Field, Forest, and Garden Botany.

Gray, Asa: New Manual of Botany. 7th edition.

Griggs, Robert F.: Botanical Survey of the Sugar Grove Region.

Hyde, J. E.: Field Trip to Newark and Vicinity. 1919.

Jones, Herbert L. Flora of Licking County. Bui. Sci. Lab. of Denison Uni-
versity. Vol. VII, pp. 1-103, 1892.

Smith, J. Warren, The Climate of Ohio. Bui. 0. Ag. Exp. Sta. 235: 185-209,
1912.

PLATE XVII

Plan of the Denison Campus, Showing Botanical Areas

/

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE XVII

Ctwel<in<f /fejy

PLATE XVIII

The Noeth Wood with Hydro phyllum in Bloom

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE XVIII

DWIGHT MUNSON MOORE SURVEY OF CAMPUS OF DENISON UNIVERSITY

PLATE XIX

Shrubbery Flanking the Walk Leading to Doane Academy Building

Bulletin Scientific Laboratories Denison University Vol. XX

PLATE XIX

DWIGHT MUNSON MOORE

SURVEY OF CAMPUS OF DENISON UNIVERSITY

THE UNDERGROUND MIGRATION OF OIL AND GAS

THE PROBLEM
KIRTLEY F. MATHER

A necessary antecedent to the flow of oil or gas in commercial
quantities into a drill hole is the concentration of a considerable
amount of volatile hydrocarbons in a small space under condi-
tions suitable to its ready release. There is much evidence for
the belief that a very great percentage of the world’s petroleum
and natural gas has originated in the midst of finely divided
sediments, the muds, oozes, clays and shales. It is also apparent
that oil and gas wells, with few exceptions, derive their valued
products from the midst of comparatively coarse-grained sands
and sandstones or from the larger crevices of limestones and
shales. Disseminated broadly through fine grained sediments,
the hydrocarbons are valueless, except in so far as they may
be removed by expensive treatment of the rocks. Concentrated
in limited portions of sand or sandstone, these same compounds
become one of the most valuable sources of energy and power
available to man. The history of oil and gas particles from the
time of their origin to the moment when they enter the casing
of a well is not only interesting; a knowledge of it is essential
to the application of geology to the oil and gas industry. The
ability to determine the probable location of new fields in ad-
vance of drilling and the most favorable directions of extension
of existing fields depend on a clear understanding of the laws
governing the movement of hydrocarbons through the rocks
and of the conditions which control the action of those laws.

This movement seems to comprise two phases, of differing
nature and presumably therefore resulting from different causes.
The first of these is the migration of oil and gas out of the fine-
grained source rocks into the coarser-grained sediments. This
results in the segration of the available hydrocarbons in ‘‘sands.”

155

156

KIRTLEY F. MATHER

It may be conveniently referred to as transverse migration, for
the direction of movement is in general across the bedding planes
of the rocks from one stratum to another. The second phase
involves the concentration of mobile hydrocarbons in certain
areas within the extent of the more porous beds. It must
depend upon lateral movement of the oil and gas within a stra-
tum or series of strata and may be called parallel migration,
for the direction of movement is more or less parallel to the
bedding planes. Both sorts of movement are involved in the
origin of most accumulations of oil or gas of economic value.

Before drawing any conclusions as to the probable causes of
these migrations in any particular case, it will be well to review
all possible motive forces which may have been in any way re-
sponsible. Having assembled the data it will then be less diffi-
cult to select the more important agents and observe how they
may have cooperated in the local accumulation of oil or gas.

THE MOTIVE FORCES

Strictly speaking, there are but two forces which in the last
analysis may be the ultimate causes of underground migration
of fluids or vapors; these are (a) gravitational force and (6)
molecular force. Both of these forces, however, may operate
in several ways. The direct action of either may affect oil and
gas indirectly through a long chain of intermediate causes and
results. Interaction and reaction between the two introduce
a number of complications. A somewhat arbitrary grouping
of the many proximate causes of migration must therefore be
adopted.!

Induration of sediments

The genesis of oil and gas depends upon the entrapping of
plant and animal tissue in the midst of accumulations of inorganic
debris, which whether deposited by water or by wind, are at
first loosely heaped together. The consolidation of fragmented

1 For a classification of causes of oil migration different from that adopted
here, see V. Zeigler, The Movements of Oil and Gas Through Rocks, Economic
Geology, vol. 13, pp. 335-348, 1918.

.UNDERGROUND MIGRATION OF OIL AND GAS

157

material into ^ 'rocks/’ as that term is popularly used, is accom-
panied, at least in part, by the conversion of organic substances
into bitumens. Both processes involve, or may involve, transi-
tion through a number of stages, none of which is separated from
its neighbors by hard and fast subdivisions either in time or in
space. Induration of sediments, and distillation of oil and gas
progress simultaneously from the time of deposition on sea or
lake floor or along the river flood plain. Each affects the other,
sometimes favorably, sometimes adversely; but most important
is the influence which induration of sediments has upon the
location of the products of distillation. For purposes of anal-
ysis it is convenient to consider the processes of consolidation
of fragmented material into "solid rock” under two heads:
(1) compacting of sediments, (2) cementation of sediments.
As a matter of fact, of course, the two processes may proceed
more or less simultaneously.

Gom'pacting of sediments

Much information of great importance to petroleum geolo-
gists concerning the consolidation of sedimentary material is
wanting. Careful observations of the changes now going on
beneath the shallow water of marginal seas are needed to make
possible accurate interpretation of the results of similar changes
which have taken place in the past. Such studies have been
made by few, but will doubtless become a more important part
of the education of the geologist of the future.

Sediments deposited by moving water must be at first loosely
heaped on the basin floor; pore space is at a maximum; open
spaces are filled with water. With increase of burden due to
continual deposition of debris the loose accumulation must
settle and be compressed into smaller dimensions. Shrinkage
of volume beneath the weight of the overlying debris may greatly
reduce the thickness of the accumulations. Shaw^ reports,
for example, that the shore of the Mississippi delta “is in places

2 E. W. Shaw, The mud lumps at the mouths of the Mississippi; U. S. Geol.
Survey, Prof. Paper, 85-B, pp. 11-27, 1913.

158

KIRTLEY r. MATHEK

actuallj^ retreating, not so much by sea erosion as by settling,
which in places predominates over upbuilding.” This com-
pacting of material must necessarily squeeze out fluids from
the dwindling pores.

Sedimentary debris comprises three classes of material, clay
particles, sand grains, and calcareous fragments, distinguished
on the basis of composition and shape of individual particles
rather than on the basis of size. Theoretically there should
be an equal amount of compacting of earthy materials of the
same composition and individual shape, under the same weight
of overburden and with an equal time for adjustment, regardless
of the dimensions of the the particles. Such classifications ac-
cording to size as that of the Bureau of Soils, which applies the
term sand to all earthy materials with dimensions between 0.05
and 1.0 mm., the term silt to those between 0.005 and 0.05 mm.,
and the term clay to all particles less than 0.005 mm. in diameter,
are of value in this connection merely because they are also
more or less perfect classifications according to chemical and
mineral composition and therefore according to shape. Silt
and clay particles are in a large degree tabular in shape, so they
may fit together, like bricks in a wall, with small and few voids
between them. Resistance to crushing of individual flakes is
comparatively slight, so that flakes which do not assume ap-
proximately parallel orientation are broken and the fragments
pushed into the proper plane. Sand grains, on the contrary,
are roughly equidimensional or spheroidal in shape, so that they
must fit together, like field stones in rubble-work, with large
interstices between them. Crushing strength of individual
grains is proportionally very much greater. Consequently,
in any bedded deposit of interstratified clay and sand, the com-
pacting of the clay strata is many times as great as that of the
sand layers, and because reduction of pore space is propor-
tional to amount of compacting, fluids will be squeezed from the
midst of the clay much more completely than from the voids in
the sandy beds. Calcareous debris would probably be inter-
mediate between clay and sand in its reaction to compacting
stresses.

UNDERGROUND MIGRATION OF OIL AND GAS

159

Beyond doubt, the first stages of formation of organic material
into bitumens are contemporaneous with burial in the silt or
ooze of the basin floor. Synthesis of oil and gas is at a maximum
in the midst of muds and silts, and is at a minimum in sandy
beds. Compacting of the former drives out the fluids and gases
to a great extent. Some of these escape upward into the water
or air above the accumulating sediments, but much of them
must first pass through the pores and openings of interbedded
sandy layers. Here differential surface tension and viscosity
tend to hold the newly formed petroleum, and may effectively
segregate it in the coarser beds. Thus at the very start of the
process of oil formation this transfer of oil from its place of origin
in the muds to its place of storage in the sands begins.

Continued accumulation of debris in the lodgment basin
means deeper burial and increased compactness of the successive
strata. More and more of the fluid content of the muds and
shales is forced out, and more impenetrable become the over-
lying strata which prevent the escape of the increasing volume
of oil or gas from the sandy reservoirs into which it has been
driven. Eventually the muds, silts, and clays become shale
and the sands become sandstone. Loose debris is now “solid
rock” and compacting of sediments becomes henceforth a quanti-
tatively minor matter. Shale and sandstone alike acquire suf-
ficient rigidity and strength to support the weight of a consider-
able thickness of overburden.

Nevertheless, compacting does not entirely cease when the
sediments are consolidated into “rocks.” Somewhere below the
surface is a zone below which voids cannot exist within the
rocks; deformation there takes place by rock flowage rather
than by rock fracture. The thickness of overburden necessary
to produce sufficient pressure to close all openings is generally
believed to be about eleven miles, and the notion is prevalent
that a “zone of flow” exists at some such depth as that. It
should be noted, however, that the eleven-mile column is neces-
sary to deform the strongest rocks, while the weaker rocks will
“flow” under much less pressure. The “zone of flow” is not a
true “zone,” but a condition in which different rocks are found

160

KIRTLEY F. MATHER

at vastly different depths below the surface. Indeed it would
in most cases be extremely difficult if not impossible to draw a
line between compacting of sediments and rock flow; the one
grades imperceptibly into the other. The ^^zone of flow’’ is al-
most at the surface for certain materials, among which the
most conspicuous are the mud rocks which are pre-eminently
the birthplace of petroleum. The Mississippi Delta, according
to Shaw,^ seems to be affected by ‘^a bodily flowage toward the
sea.” In places the Delta front is bulging outward and upward
as the materials of which it is composed flow laterally after
having been compacted by the weight of the shallow over-
burden.

Such flpwage of the rocks may further the process of transfer
of petroleum from shales to sandstone or to limestone, but is
probably much less important than the universal compacting
which necessarily must result from the accumulation of any
considerable amount of sediment in any lodgment basin. The
movement, both of solids and of fluids, which must accompany
rock flow may greatly expedite the segregation of oil and gas
by other processes to which reference is made in the succeeding
paragraphs. In general, simple compacting precedes rock flow
and decreases in importance as the later process increases in
amount, but no sharp distinction may be drawn either between
the processes or their results.

Cementation of sediments

Consolidation of sediments is not solely nor indeed princi-
pally a matter of compacting; especially are the constituents of
sandy strata bound together by interstitial cement. Cementa-
tion may begin immediately after the rocks are subjected to
the action of ground water. It is through cementation that
sands become sandstone, and sandstones become quartzite.
Obviously, the greater the amount of precipitated cements the
less the effective pore space of the rock. If cementation com-
mences along a definite plane or at a point and proceeds regularly

3 Log. cit., pp. 17, 18.

UNDERGROUND MIGRATION OF OIL AND GAS

161

outward, it will necessarily exclude ground water, oil, or gas,
from the pores which it closes and may drive fluids and gases
into other portions of the reservoir. The distinction between
the sands reported by the driller as tight (and dry) and those
stated to be loose (and water, gas, or oil-bearing) is probably
in most cases a result of differential cementation.

At present, however, it is impossible to say whether a tight
sand is devoid of oil because the cementation of the sand drives
out its fluid content or because the presence of cement filling the
pores prevented the immigration of valued hydrocarbons;
probably the latter is more often the case. In general, it should
be observed that the presence of oil in a rock pore will itself
hinder if not entirely prevent the filling of that pore by cement
carried in aqueous solutions. Between the encroaching cement
and the retreating oil there must always be a buffer of water.
It is doubtful whether progressive cementation of sediments
has even been an important cause of the migration of oil or gas.

Capillary action

Molecular forces are by no means completely understood.
The exact nature of both inter-molecular and intra-molecular
attractions and repulsions are more or less of a mystery The
best that can be done in the present state of knowledge is to
give names to the more obvious phenomena resulting from these
forces, and to postpone the enquiry as to their fundamental
causes until the physicist and the chemist have completed their
research concerning them.

Of the phenomena attributable to molecular action, the two
most important in this connection are capillarity and surface
tension. Surface tension is the property ‘Vhich exists in the
surface film of all liquids and tends to bring the contained volume
into a form having the least superficial area.” It is this prop-
erty which causes small quantities of oil, water, mercury, or
other fluids to form into spherical “drops” when scattered over
the surface of a solid or sprayed into the air. It apparently
results from cohesion, the attraction existing between closely
adjacent molecules of the same substance, a force which is “quite

162

KIRTLEY F. MATHER

insensible between two portions of matter separated by any
distance which we can directly measure.’’ Consequently within
a liquid body each molecule which is more than about the twenty-
thousandth part of a millimeter distant from the surface is
affected equally on all sides by cohesion with other molecules
which surround it. But the molecules in the surface film are
on the whole attracted inward, and tension results. The amount
of this tension depends upon the curvature of the surface, the
composition and temperature of the liquid, and the nature of
the surrounding medium or media.

Capillarity'^ is ^The action by which the surface of a liquid,
where it is in contact with a solid is elevated or depressed.”
Because of it the surface of the water in a glass is not plane but
is curved upward around the margins, and for the same reason
the top of the mercury column in a thermometer is convex
upward instead of flat. But the phenomenon is best observed
when liquids enter tubes or spaces of small diameter or width,
for then it may cause the liquid to move in a direction quite
contrary to that in which it would be impelled by gravity. The
absorption of a drop of ink by blotting paper in which the tiny
air spaces between the paper fibers draw the fluid upward, or
the continual supply of oil through the wick of the kerosene
lamp, which keeps the flame steadily burning several inches
above the oil reservoir, are familiar illustrations Capillarity
is in part a result of surface tension but depends also upon the
forces of adhesion, forces which act between closely adjacent
molecules of unlike substance, those of the liquid and of the
containing solid.

Capillary action may best be considered as operating in tubes
of small diameter or in fissures of minute width. Openings into
which a liquid is drawn with a force greater than that exerted
by gravity may be referred to as capillary openings. In such
openings the mean height to which the fluid rises varies inversely
as the radius of the tube or the width of the fissure. The capil-

^ For a clear exposition of capillarity see J. C. Maxwell’s article ‘‘Capillary
Action,” revised by Lord Raleigh, in Encyclopedia Brittanica, eleventh edi-
tion, 1910.

UNDERGROUND MIGRATION OF OIL AND GAS

163

lary pull also varies with the surface tension of the fluid and is
at once affected by any change in surface tension A water-air
surface at ordinary temperatures has a tension of 70 to 75 dynes
per square centimeter, and so far as water is concerned, all
tubes of diameter less than 0.508 mm., and all smooth fissures
less than 0.254 mm. wide are capillary. According to Wash-
burne,'^ ^ A salty water, such as that commonly found in oil fields,
having a density of 1.14 at 20°C., would have a surface tension
of about 79 dynes per centimeter,” while Penns^dvania crude
oil with a specific gravity of 0.852 displayed a surface tension of
only 24.1 dynes per centimeter at 20°C. The same author is
responsible also for the statement ^That all crude oils have low
surface tension, probably in the neighborhood of 25 dynes, except
only the oils that have lost all of their light constituents, which
are of no consequence in problems of deep migration.” Because
of their low surface tension, only those tubes with a diameter
of less than about 0.25 mm., and fissures not over 0.13 mm.
wide are capillary openings with respect to the average crude oil.

Surface tension decreases with increase in temperature and
becomes zero at the critical temperature of each substance;
capillary action is therefore limited to the outer shell of the
earth and cannot be operative at great depths where tempera-
tures are high. ^'The effect of pressure on surface tension (and
therefore upon capillary action) is unknown, but is presumably
small.”®

Finally in summing up these physical factors concerning capil-
larity, it should be noted that although capillary action may
draw fluids into small passageways within the rocks it cannot
of itself induce continued flow through these passageways.
Since it is an expression of surface tension, capillarity is opera-
tive ‘^only when there is a free liquid surface within the capil-
lary.” Once the capillary opening is filled with liquid, capillary
action ceases, unless perchance another liquid of different sur-
face tension approaches an opening of the tube.

® C. W. Washbiirne, The capillary concentration of gas and oil, Trans. Am.
Inst. Min. Eng., vol. 50, pp. 829-858, 1915.

® John Johnson and L. H. Adams, Observations on the Daubree experiment
and capillarity in relation to certain geological speculation, Journ. GeoL, vol. 22,
pp. 1-15, 1914.

164

KIRTLEY F. MATHER

Capillary action on crude oil in dry materials; experimental data

Dissemination through fuller’s earth. Experiments conducted
by David T. Day^ indicate that in spite of its relatively low sur-
face tension crude oil disseminates rapidly in dry, finely divided
material such as fuller’s earth. Not only does oil rise directly
against gravity to a height of 5 or 6 feet in a tube packed with
fuller’s earth, /^but if the tube be sealed at the upper end the oil
will still rise in the tube, driving out the air in the pores of the
earth and compressing it in the upper part of the tube with
a pressure sufficient to blow out the clay if the top of the tube
be suddenly broken off and the air thus released.”

No experimental data are available as to the exact size of the
capillary spaces through which the oil is thus forced to migrate,
but somewhat similar movement is known to take place through
finely divided quartz sand and amorphous silica.^ More than
likely the upper limit of pore sizes conforms to that suggested
above as the theoretical dimensions of capillary openings for
crude oil.

Effect of dissemination upon composition of crude oil. ^^When
a glass tube is packed tightly with dry fuller’s earth, and one
end is allowed to stand for one or two days in crude petroleum
the oil diffusing up through the clay fractionates to a consider-
able extent. Thus, when the upper fifth portion of the clay is
dropped into water, a lighter gravity oil is driven out by the
water. This first fraction is entirely colorless. The lower frac-
tions are heavier and more and more highly colored. The bottom
section may be almost solid, and is darker in color than the
original oil. A fractionation by diffusion has been effected,
which is similar to fractionation by distillation, but is not so
complete.”^ Richardson^*^ made similar tests with crude oil
from Texas and found that sulphur compounds could be sepa-
rated from that oil by their failure to migrate into fuller’s earth.

7 David T. Day, The conditions of accumulation of petroleum in the earth,
Am. Inst. Min. Eng., Trans., vol. 41, pp. 219-224, 1911.

® David T. Day, Experiments on the diffusion of crude petroleum through
fuller’s earth. Science, N. S., vol. 17, pp. 1007-1008, 1903.

9 Day, loc. cit., p. 222.

Clifford Richardson, Journ. Soc. Chem. Ind., vol. 21, pp. 316-17, 1902.

UNDERGROUNI) MIGRATION OF OIL AND GAS

165

Apparently ^^the size of the capillaries is of great consequence
in these diffusion phenomena. Finely divided material, such
as amorphous silica, has no observable fractionating-power
on oils that are readily fractionated by dry clays. Quartz
sands likewise exhibit practically no selective action, but dried
shale of Devonian age proved to exert an action similar to that
of fuller^s earth.

As shown by Engler and others, there is no chemical change
in this process; fractionation by capillary dissemination is
merely a mechanical separation of slowly diffusing liquids from
those which pass more rapidly into the capillary spaces.

Application to the conditions existing in the earth

Except in arid regions, the pores of all sedimentary rocks
near the surface of the earth are more or less completely filled
with water; but the deeper levels which have been penetrated
by the drill in the Appalachian oil fields and elsewhere are ap-
parently dry. Oil field waters will be discussed in a subsequent
section of this paper; it is here only necessary to call attention
to the fact that the amount of water found in the sedimentary
rocks of most oil fields decreases with depth. In the Appa-
lachian region ^ffresh water is found in appreciable amounts in
one or more beds as a rule to a maximum depth of 200 to 800
feet. Brackish or salt water occurs below the fresh water at
depths ranging from 400 to about 3000 feet. In a few wells
out of the thousands drilled, salt water was found at greater
depths than 3000 feet, but in all cases the amount and head of
this water was very small, regardless of the porosity of the
containing bed. In many wells open porous sandstones from
1000 to 3000 feet from the surface show no water. Many of
these were found to take up, with surprising rapidity, water
poured into the well in the process of drilling. This is by no
means equivalent to stating that shales three or four thousand
feet below the surface of the earth are known to be dry, but it

“ M. J. Munn, The Anticlinal and hydraulic theories of oil and gas accumula-
tions, Econ. GeoL, vol. 4, pp. 509-529, 1909.

166

KIRTLEY F. MATHEK

strongly suggests the possibility that at some such depth certain
of the finer grained sediments may be nearly or quite devoid of
moisture. If so, oil entering or present in the small pores of
these shales would be broadly disseminated throughout the
rock by capillary action. This is just the opposite movement
to that requisite for the accumulation of oil in economic quanti-
ties, but such migration may have been preliminary to certain
processes of accumulation.

The influence of such capillary migration upon the composi-
tion of oils subjected to it is probably the only effect of quanti-
tative importance to the oil industry. As suggested by Day,
it is possible to explain the difference in the nature of the oil of
different fields by the hypothesis ^That dark colored oil (possibly
containing sulphur and asphalt) entered shales varying in frac-
tionating-power, due to varying porosity or moisture,’’ and was
there fractionated into oils of various colors and compositions.
It is even possible, although in the opinion of the present writer
scarcely probable, that the oils from the Carboniferous rocks
of Pennsylvania and vicinity are ^The same as the Ordovician
limestone oils of Ohio, with the sulphur removed by diffusion.”
Furthermore, the long series of quantitative tests made by
Gilpin and Cram^- indicate that the paraffin hydrocarbons dif-
fused farther than the unsaturated or asphaltic hydrocarbons
which were consequently left behind in migration due to capil-
lary attraction. The strong contrast between the paraffin oils
of Pennsylvania and the asphaltic oils of California may be an
illustration of the effect of capillary dispersal resulting in frac-
tionation or filtration . in the one case and the absence of this
action in the other.

Differential capillarity of oil and water; experimental data

In the experiments conducted by Day, Gilpin and Cram,
above referred to, in which crude oil was drawn upward by
capillary action into tubes packed with dry fuller’s earth, the

J. E. Gilpin and M. P. Cram, The fractionation of crude petroleum by
capillary diffusion, U. S. Geol. Survey, Bull. 365, 1908.

UNDERGROUND MIGRATION OF OIL AND GAS

167

oil was later displaced from the earth by water. Fractions of
the earth removed from the tube and dropped into water, rapidly
gave up their content of oil, and the pores formerly occupied by
oil became filled with water. Several experiments which ap-
proximate more closely the conditions existing within the earth
have been described by McCoy, Mills, and Cook.i-^
of McCoy’s experiments, an open glass cylinder was placed in
a pan of wet sand, so that the sand filled the lower one-third
of the cylinder. The water had free access from the sand in the
pan to the sand in the cylinder. A layer of oil-saturated mud,
made by adding Oklahoma crude oil (38°Beaume) to a mixture
of dried clays, the particles of which measured from 0.005 to
0.001 mm., was placed in the cylinder upon the wet sand; this
mud occupied about one-third of the cylinder and was above the
level of the water in the pan. The cylinder was then filled with
dry sand, and the top sealed with a tube attachment to a closed
barometer. Within twenty-four hours, the water migrated up-
ward about 1 cm. into the mud, and the oil moved about the
same amount into the dry sand; some of the oil also migrated
down into the wet sand and collected in the larger openings;
the mercury rose in the closed barometer to a height of about
2.5 cm. above that corresponding to the atmospheric pressure.
As thus described the experiment is essentially a modification
of the Daubree experiment of 1861, in which water passed
through sandstone against pressure, or of the ^Atmometer”^^
which gives similar results. The most significant, obvious

A. W. McCoy, Some effects of capillarity on oil accumulation, Jour. GeoL,
vol. 24, pp. 798-805, 1916; reprinted. Bull. Southwestern Assoc. Petrol. Geolog.,
vol. 1, pp. 140-47, 1917.

R. V. A. Mills, Experimental Studies of subsurface relationships in oil and
gas fields, Econ. GeoL, vol. 15, pp. 398-421, 1920.

1^ C. W. Cook, Study of capillary relationships of oil and water, Econ. GeoL,
vol. 18, pp. 167-72, 1923.

1® Daubree, Etudes Synthetiques de Geologic Experimentale, Paris, 1879,
pp. 238.

17 J. Johnston and L. H. Adams, Observations on the Daubree experiment and
capillarity in relation to certain geological speculation. Jour. GeoL, vol. 22,.
pp. 1-15, 1914.

168

KIRTLEY F. MATHER

result in the present connection is the downward migration of
oil from the extremely small pores between the mud particles
to the larger interstices between the sand grains, which had
previously been filled with water.

In McCoy’s second experiment, a layer of wet sand was ar-
ranged in the form of an anticline between two layers of oil
saturated mud. The sand grains near the crown of the artificial
anticline were small, all passing a 40 mesh sieve, while those on
the limbs were coarser, none passing a 10 mesh sieve. The top
of the rectangular glass box containing the three layers was
sealed with paraffin and water allowed to enter through openings
at the lowest horizon of the sand, but was kept at a level below
the top of the curve in the sand. Water entered the mud both
above and below the sand layer, and replaced about an inch of
the oil in the mud. The displaced oil moved into the interstices
between the coarser grains of sand and within 24 hours there was
an ^‘oil pool” in both limbs of the anticline on either side of its
water-filled crest. These results could not have been effected
by simple capillary pressure such as that operative in the Dau-
bree experiment because the spaces between sand or mud parti-
cles were occupied with either oil or water and the paraffin seal
over the top of the box prevented evaporation. There were,
however, certain forces at work which drove oil out of small
openings into large ones and at the same time drew water from
the larger to the smaller pores, regardless of the direction involved
in the transfer or of the tendency of oil to float on top of water.

In many of Mills’ experiments, coarser sands were used, and
water circulation, sometimes under considerable head, was in-
volved. • Few of them afforded much opportunity for capillary
action to display itself. Nevertheless, capillary adjustments
seem to have occurred between oil and water in saturated strata.
These, states Mills, are restricted within short lateral ranges,
amounting to only a few centimeters in his experiments. His
conclusion was that the principal role of capillarity, in saturated
strata, is to retard rather than to promote fluid movements.

UNDERGROUND MIGRATION OF OIL AND GAS

169

Theoretical considerations

As stated above, the surface tension of crude oil is between
one-third and one-half that of water. Capillary action must
therefore exert a much stronger pull upon water than upon oil.
According to Washburne/^

the amount of the capillary pull varies inversely as the diameter of a
pore, hence the constant tendency of capillarity is to draw water,
rather than oil, into the finest of openings, displacing any gas or oil
in the latter. Gas itself is not drawn into capillaries by the action of
surface tension, and it can leave the fine pores without any capillary
resistance. It is therefore the most quickly and most completely
gathered in the largest spaces available. Moreover, capillarity resists
any movement of water from fine toward large pores more than it
resists the movement of oil or gas in that direction. In short, water
enters fine capillaries about three times as readily as oil, and it en-
counters about three times as much capillary resistance in leaving them.

The final result of this action must be the concentration of nearly
all the gas and oil in the openings having least capillary power, namely,
in fissures if present, and in the larger rock pores. This appears to be
the general rule in oil fields, where the pores of the coarser-grained
rocks contain practically all of the oil, while the pores of the adjacent
fine-grained rocks contain practically no oil.

Here, too, is a possible explanation of the phenomena dis-
played in the experiments described above. Differential capil-
lary attraction may be competent to induce the migration of
water from larger pores into adjacent ones originally filled with
oil and to force the oil out of these spaces into those originally
occupied by water.

There is, however, a possible fallacy here.^^ In comparing
the surface tension of oil and of water, the comparison was
between the tension on an oil-air surface and that on a water-
air surface. In the experiments with saturated sediments, and
presumably under most conditions obtaining within the earth,

W. Washburne, The capillary concentration of gas and oil, Trans. Am.
Inst. Min. Eng., vol. 50, pp. 823-858, 1915.

Cf. Johnson, R. H., The Time Factor in the Accumulation of Oil and Gas,
Bull. Am. Assoc. Petrol. Geologists, vol. 5, pp. 475-481, 1921.

170

KIRTLEY F. MATHER

it is the molecular forces operating on an oil-water surface which
are significant. Here quantitative data are not available;
Cook’s tentative conclusion, that the minimum size of opening,
which will allow the interchange of oil and water to occur, is
considerably larger than the minimum which will permit the
capillary movement of either oil or water alone, would suggest
that the simple numerical ratio cited by Washburne does not
directly apply.^® Nevertheless, it is evidently a fact that under
certain conditions this interchange of oil and water does take
place exactly as though the movements were induced by capil-
lary action. Probably, as Cook points out, the effects of dif-
ferential adhesion of oil and water, especially the far superior
adhesion of water for rock, are quantitatively more important
than those resulting from differential cohesion of these same
liquids as expressed by their surface tension. The phenomena
of adhesion undoubtedly play an important part in capillary
action and may be largely responsible for the interchanges of
oil and water, which have been observed.

The direction of the movement resulting from such interchange
is entirely independent of gravity; impelled by differential capil-
lary forces, oil or gas may migrate upward or downward or
laterally with equal facility. Migration would be from smaller
to larger openings in the rocks, and presumably cannot reverse
itself so long as water is present. Probably, neither oil nor gas
can, under ordinary conditions, move into a stratum or portion
of a stratum of rock which contains no openings of greater than
capillary dimensions (for water) and is thoroughly saturated
with water.

Application to the conditions existing in the earth

These considerations make evident at once the imperative
necessity of data concerning the pore spaces existing in sedi-
mentary rocks at different stages in their history. Not only
should the total amount of pore space be known, but, of probably

See also Skirvin, O. W., Experimental Study of the Invasion of Oil into a
Water-Wet Sand, Econ. GeoL, vol. 17, pp. 461-469, 1922.

UNDERGROUND MIGRATION OF OIL AND GAS

171

much greater importance, the size of the spaces in different
kinds of rocks under different conditions should be determined.

Porosity of sedimentary rocks. The total volume of pore space
in a rock does not depend upon the size of the rock particles but
upon their shape, assortment, arrangement, and degree of
cementation. In figure 1, for example, the total amount of pore
space in A and C, or B and D, is the same, but there is a pro-
gressive decrease in the diameter of the individual pores from the
ideal case shown in A to that in D. Variations in the dimen-
sions of interstices in clastic rocks must in general be roughly
proportional to the size of rock grains, other things being equal.
It is not, however, the average size of grain which is the most
important consideration, but the proportion of extremely fine
particles which if present in sufficient amount would ^^sift”
into the larger spaces between the coarser grains and leave
openings with dimensions approximating one-sixth to one-half
the diameter of these smallest components of the rock. An
argillaceous sand might, therefore, have pore spaces the dimen-
sions of which would approximate those of the interstices between
the particles of clay in shale. The more perfect the assortment
by size and the ^Tleaner” the sand, the larger will be the voids
in the rock. But this neglects the effect of cementation which
as evidenced in diagrams E, F, and G, of figure 1, greatly in-
fluences the size of pore as well as the total amount of porosity.
With these variables, it is readily apparent that abrupt changes
in pore dimensions as well as in volume of openings may be
expected in any sedimentary series when traced laterally or
traversed vertically.

Data are not available for more than a broad approximation
covering the relative sizes of pores in shales and sandstones.
It is probable however, that interstitial spaces in most shales,
are less than 0.01 mm. in diameter, and in the finer clay shales,
especially if considerably compressed, openings would average
less than a micron (the thousandth part of a millimeter) in
cross-section. Sandstones display greater variation in size of
pores because of the limitless variations in amount of cement
and in abundance of fine constituents. The sands used by

172

KIRTLEY F. MATHER

A. Hypothetical rock with large spherical
grains, inaximam pore space.

B. Hypothetical rock with large spherical
grains, minimum pore space.

C. Hypothetical rock with small spherical D. Hypothetical rock with small spherical

grains, maximum pore space. grains, minimum pore space.

E. Irregular grains with-
out cement, showing maximum
pore space.

F. Irregular grains
with interspaces partly
filled with cement.

G. Irregular grains with
interspaces completely filled
with cement,, no pore space.

Fig. 1. Pore Space op Rocks

(Reproduced with permission from Geological Survey of Kansas, Bull. 3, pi.
Ill, 1917)

UNDERGROUND MIGRATION OF OIL AND GAS

173

King^i in measuring the observed pore space in soil and rock
are reported to have had an “approximate effective diameter”
which varied from less than 0.1 mm. to more than 2.5 mm.,
with the greater number of samples approximating 0.2 and 0.3
mm. It is entirely out of the question to apply any rigid math-
ematical formula stating the relation between pore size and sand
grain diameter. Irregularity of outline of the sand particles
is so great in the average sandstone that the common assumption
of an accumulation of spheres is scarcely an approximation to
the truth. To assume that the grains are spheres gives neither
the maximum nor minimum total porosity or size of pore. “For
simple sands with angular grains the pore space is much larger
than it is for the rounded sands of the same sizes of grains, and
in the case of crushed glass, whose grains are more angular than
those of the crushed limestone, which have a tendency to be
cuboidal in form, the pore space is the largest of all.”22 if
this is true for total pore space, it must necessarily follow that
the size of individual pores is greater in sandstones composed
of angular grains than in those composed of rounded grains of
similar sizes. The dimensions of occasional pores may equal the
diameter of the sand grains if the latter are angular. The
width of the open spaces between grains of ordinary sandstones
may therefore vary from less than a micron to more than a
millimeter. Probably the average pores of a poorly cemented
sandstone would be between 0.1 and 0.5 mm. in width.

Transverse migration of oil and gas. In any series of alter-
nating shales and sandstones, containing sufficient water to fill
the openings in the shales, oil and gas will therefore tend to move
from the shales and segregate in the sandstone strata. This
transverse movement of the hydrocarbons will not be complete.
In the first place there will almost certainly be porous lenses in
the shale beds, entirely surrounded by compact shale with finer
openings. Oil once driven into these lenses cannot afterward
return into the finer peripheral pores as long as they are filled

F. H. King, Principles and conditions of the movements of ground water,
U. S. Geol. Surv., 19th Ann. Rept., Pt. 2, pp. 59-294, 1899.

22 King, loc. cit., p. 215.

174

KIRTLEY F. MATHER

with water; hence it cannot traverse a zone of wet shale, all the
openings in which are finer than those in which the oil occurs
even though a coarsely porous sandstone may be only a few inches
distant. In the second place, a considerable fraction of the oil
will be retained in the argillaceous rocks by absorption and
adhesion, as indicated by the experiments of Gilpin and Cram-^
who state ^Vhen oil is mixed with fuller’s earth and then dis-
placed with water, about one-third of the oil remains in the
earth.” These capillary forces would probably be most effective
in their task of draining the shales of oil and gas and segregating
these substances in the sandy beds if the latter were present at
frequent intervals in the midst of a thick shale series. Recur-
rence of sandstones is more favorable than the same amount
of sand deposited in a single massive bed, but in any event it is
apparent that nothing could be more effective as a seal to stop
transverse migration of either oil or gas than a water soaked
bed of shale capping the sands. Once driven into the sandy
horizons the hydrocarbons are there imprisoned, unless super-
capillary fissures traverse the shales.

A consideration of the variability of dimensions of pore spaces
in any sedimentary series makes it evident that migration of
oil and gas due to capillary forces cannot in most cases extend
over great distances. The very forces which impel segregation
in the coarser pores make it impossible for hydrocarbons to
traverse the average sedimentary series from bottom to top
unless there are open fissures to serve as channels. Nor can the
oil be gathered by lateral movement within a bed from distant
points to a center of accumulation. Capillarity may only be
appealed to as the force responsible for the transfer of oil or gas
from one bed of fine-grained rock to a closely adjacent bed of
coarser or more open texture, but in probably every oil field
other forces have cooperated to concentrate the fluid in small
enough compass to make an accumulation of commercial value.

Localization of capillary segregation near surface of earth.
Surface tension decreases with increase in temperature until

23 J. E. Gilpin and M. P. Cram, The fractionation of crude petroleum by capil-
lary diffusion. U. S. Geol. Surv., Bull. 365, p. 33, 1908.

UNDERGROUND MIGRATION OF OIL AND GAS

175

at the critical temperature of the substance it vanishes. The
tables prepared by Johnston and Adams^^ indicate that with
a temperature gradient of 1°C. per 100 feet the total pressure
upon a water surface inside pores having diameters of 0.01
microns at a depth of approximately 1 mile would be no greater
than the pressure outside the pores due to overlying rock.
^^Alor cover, the surface tensions of all but the lightest hydro-
carbons decrease much less rapidly than that of water for each
increment of temperature, so that the surface tension of water
does not have such great excess over that of oiF^ at depths of a
mile or two as it does in the zone of lower temperature close
to the earth’s surface. It is therefore probable that capillary
segregation of oil and gas must all be effected within two or three
miles of the ground surface. At greater depths oil must remain
disseminated throughout the shales, if that were its original dis-
tribution, unless it had migrated into the sandy strata during
the time when the beds concerned were closer to the surface.

Gravitation

Migration of oil is caused directly and simply by the force of
gravity only under certain restricted conditions. To permit
oil to flow “down hill” in obedience to the attraction of gravity,
the oil drops must be in openings not filled with water, and of
super-capillary (for crude oil) dimensions. If the openings are
tubular, their diameter must be greater than 0.25 mm.; if fissures,
they must be more then 0.12 mm. wide. Pores and crevices of
greater size than this are probably present in many sedimentary
rocks near the surface of the earth, but more commonly they are
filled with water. If water is absent from such a coarsely porous
rock into which oil has moved, the oil will flow to. the lowest
portion of the porous stratum and may there collect in com-
mercial quantities. Or if only sufficient water is present partly
to fill the open spaces in the bed, the downward passage of the
oil will be arrested when it reaches the water-bearing portion
of the porous rock.

24 J. Johnston and L. H. Adams, Observations on the Daubree experiment and
capillarity in relation to certain geological speculations. Jour. Geol., vol. 22,
p. 13. 1914.

176

KIRTLEY F. MATHER

Differences in specific gravity

Although the direct influence of gravitation is probably not
generally important in causing underground migration of oil
or gas, its indirect effect through differences in specific gravity
of fluids and gases is unquestionably of prime importance. Most
crude oils are quite appreciably lighter than water, especially
the heavy salt water which is commonly associated with oil.
The excess in specific gravity of water varies from more than
35 per cent, in the case of a very light oil compared with a heavy
brine, to less than 5 per cent, if heavy oils be compared with
dilute brines. An ordinary crude oil, with a specific gravity
of 32° or 33°Baume, is about 20 per cent lighter than the ordi-
nary salt water with which it is commonly associated. If,
then, petroleum and water are associated together in openings
of super-capillary size, the difference in specific gravity will
result in a tendency for the oil to rise until its upward progress
is barred by a rock mass in which the openings are all of capillary
size and are filled with water, or until it reaches the surface of
the water body which displaces it.

Gravitational sorting of oil and water. The tendency of water
thus to drive oil upward in coarsely porous strata is unques-
tioned; the actual movement of oil due solely to differences in
specific gravity is by no means certain. If drops of oil are
squeezed from a fountain pen filler against the bottom and
sides of a basin filled with water, it may be observed that ^^most
of the drops cling persistently to the vessel and do not rise
through the water.’’ The slight difference in weight between
the small drop of oil and an equal volume of water is not suf-
ficient in itself to overcome adhesion between the liquid and the
adjacent solid, although the area of solid contact is very much
less than that which would be operative if the same drop of oil
were spread out in the pores of the ordinary sandstone. The
drops of oil in the basin of water may be dislodged by stirring
the water or by tapping the vessel; or if separate drops are so
closely adjacent that cohesion and surface tension unite them
into a single large drop, its size may be sufficient to induce

UNDERGROUND MIGRATION OF OIL AND GAS

177

enough lifting force of water displacement to overcome adhesion
and inertia, and to float it freely upward. All three of these
phenomena are active in the interstices of the rocks. Circula-
tion of ground water may simulate the first; crustal movement,
tidal kneading, and earthquake vibrations are the second;
and molecular forces are probably identical beneath the surface
of the earth to those in the laboratory. But, in the petrolif-
erous rocks, if an oil drop starts to obey the impulse of gravita-
tive displacement, its upward progress is hindered by the fric-
tion of the rock surfaces past which it must move. The retard-
ing effect of friction cannot be quantitatively determined from
the data now available; it is entirely possible that it may in
most instances prevent effective gravitative assortment of oil
and water, although this is by no means certain.

Gravitational sorting of gas and water. The displacement of
gas bubbles in water is quite another matter. Gas rises through
water-saturated sandstone several hundred times as readily as
oil. Differences ' in specific gravity are probably quite compe-
tent to concentrate gas above the water body in a porous rock
mass. It is probable that soon after the formation of a bubble of
gas, as a result of chemical action, change of temperature, or
increase in pressure, the bubble would rise through the water
in any supercapillary fissure or pore until ascension was stopped
by a barrier of water-filled spaces, none of which were of more
than capillary dimensions.

Effect of gas migration in transporting oil. But if while being
forced upward the bubble of gas touches a droplet of oil clinging
to the wall of Assure or pore, it will be surrounded by a thin
film of oil, for oil has an extraordinary capacity of spreading
along any surface between water and gas.^^ Each bubble of
gas rising from its place of origin or later moving upward through
rock cavities may carry with it a pellicle of oil and thus accom-
plish gravitational sorting of oil as well as of gas. When the
gas bubbles with their films of oil unite in the space to which
they are driven by the lifting force of water displacement, the

25 Johnson, R. H,, The accumulation of oil and gas in sandstone, Science,
vol.,35, pp. 458-9, 1912.

178

KIRTLEY F. MATHER

oil films will aggregate because of surface tension into drops
which will further coalesce into fluid masses separating the
gas above from the water below. It is, of course, true that the
volume of gas required is many times the volume of oil which
it would lift in this way but recognizing the limitations upon
the process it nevertheless seems potent to accomplish impor-
tant results in the migration of petroleum.

Movements of underground water; nature of the movement

Movement of the water beneath the surface of the earth neces-
sarily involves movement of the oil or gas which may be in its
path. Underground water, a term used to comprise all aqueous
solutions beneath the earth’s surface, includes water from many
sources and under many various conditions. Much of it is
seepage, fresh or salt water, which has filtered downward from
the surface; some is connate, fresh or salt water buried with
sediments; while a small part of it is juvenile, primitive fluids
expelled from molten magma or igneous rock by crystallization
or heat. Above the water-table — below which most openings
in the rocks are filled with liquids — underground water is in
more or less constant motion from higher to lower levels.
Below the water table, motion is in general slower, and great
volumes of water may for motion periods remain practically
stagnant. The direction of motion is there determined by
pressure and is from places of greater to places of lesser pressure
or hydrostatic head. This frequently results in an upward
creep and lateral oscillation.

The chief causes of movement of water below the water-table
are (a) gravity, expressed in the familiar statement that water
tends to seek its own level; {h) changes in temperature which
ma3^ result from the earth’s general heat, from the heat of crus-
tal movements, involving crushing or friction, from chemical
reaction, or from igneous intrusion; (c) compacting of rocks by
burial, or expansion of rocks following erosional stripping of

2® R. A. Daly, Genetic classification of underground volatile agents, Econ.
Geol., vol. 12, pp. 487-504, 1917.

UNDERGROUND MIGRATION OF OIL AND GAS

179

covering; (d) expulsion of juvenile water from igneous masses
during crystallization; (c) expansion of gas which may be either
of abyssal origin or newly formed by pressure upon organic
materials at moderate depths.

Washburne infers

a small, but locally active, very slow, outward creep of the rock fluids
(liquid or gas or both) due to pressure from below. The principal
reason for the inference is based on plotting the distribution of pres-
sures in the sands of different flelds of the United States and of Canada
for which data are available. The data are not sufficiently complete
to warrant final conclusions, bufc there are many instances in which
the downward increase of pressure between sands, and the increase
above the surface pressure, exceed the corresponding hydrostatic

head It seems significant that excess pressures are most

common in the more fractured regions, such as Baku and the Gulf
Coast, where the deep communication appears to be more open than
elsewhere. Other arguments for this ascent are found in the excess
temperatures in oil fields, in the distribution of oils and gases of filtered
and unfiltered types, in the excess of chlorine in the associated water,
and in the abundance of helium in the deep wells of Kansas.

Effect of movement upon accumulation of oil

The chief contribution of ground water circulation to the
underground accumulation of oil and gas in commercial quanti-
ties is probably made as a conditioning rather than as a causal
agent. Movement of subterranean fluids may assist in over-
coming the adhesion and inertia of oil globules, which might
otherwise prevent differences in specific gravity from accom-
plishing gravitative sorting. Johnson^^ states, for example,
that differences in specific gravity, and in capillary action seem
remarkably impotent when everything is at rest, but that as-
sisted by a little movement these differences bring about very
important results. If oil-soaked sand is placed in the middle
of a horizontal tube and w^ater-soaked sand is placed at either
end, the tube may remain at rest a very long time without any

27 Washburne, loc. cit., p. 956.

28 R. H. Johnson, Discussion of Capillary concentration of gas and oil, Am.
Inst. Min. Eng., Trans., vol. 50, pp. 842-843, 1915.

180

KIETLEY F. MATHER

appreciable change in the relative position of oil and water.
But with a little motion that oil will gradually be distributed
above the water along the upper side of the tube. It does not
appear to be necessary to have very extensive movement, but
some degree of movement is essential.

Or, again, the slow circulation of ground water may permit
surface tension phenomena to play a part which would other-
wise be denied them. If a body of gas has been segregated
above the water in porous sands, circulation or migration of
the water may bring globules of oil to the surface of contact
between gas and water. If so, these will be held on the surface
of the water by its tension. The oil will first spread as a film
along the gas-water surface and any oil which is brought in
contact with this film must join it. In this way oil may ac-
cumulate above water in any subterranean reservoir in spite of
the slight difference in specific gravity between the two fluids.
^^Any movement of the water in the sand, which would in time
bring the various parts of the water in contact with its upper
surface, would carry bodies of oil of all sizes to the water-gas
surface, where surface tension would retain them permanently.’’

Rich believes that the

principal cause of the migration of oil and gas is the movement of
underground water which carries with it minute globules of oil and
bubbles of gas, possibly as fast as they are formed. Accumulation
results from the selective segregation of oil and gas, which, on account
of their buoyancy, always tend to work their way upward as they are
carried along and are caught and retained in anticlinal or other suitable
traps.^^

Gas expansion

Destructive distillation of organic matter, animal or vegetable,
under conditions such as those commonly occurring within the
body of the earth where free access of air is precluded, produces
hydrocarbon gases as well as liquid hydrocarbons. The process

2 9 John L. Rich, Moving underground water as a primary cause of the migra-
tion and accumulation of oil and gas, Econ. Geol., vol. 16, pp. 347-371, 1921.

UNDERGROUND MIGRATION OF OIL AND GAS

181

is a biochemical one, effected largely by the action of anaerobic
bacteria before the deposits are deeply buried or the formation
firmly consolidated. But later, if the same beds are covered
with thick accumulations of younger sediments, gas may be
formed as a result of the action of heat upon the entombed or-
ganic matter, liquid or solid. This thermochemical process^®
is accompanied by polymerization of the oil and may be furthered
by the increase in pressure resulting from burial. The two •
kinds of action are mutually complementary; the first men-
tioned dwindles to nothingness as the second increases in effect-
tiveness; the first is long continued, but the second knows no
time limit. Consequently, new gases are produced long after
the petroliferous beds are more or less completely sealed by
water-saturated ^Tover rocks.”

To these organic gases, there may possibly be added in some
localities a modicum of abysmal gas, inorganic in origin, slowly
ascending from the deeper interior. The presence of argon and
helium among the gases from the deeper sands of Kansas may
be thus explained. But regardless of any possible inorganic
contributions, these lighter hydrocarbons may be formed under
all conditions of temperature and pressure, including those far
above their critical temperatures and pressures, so that they
may be in that state of matter where the true distinction be-
tween gas and liquid disappears.

Gas expansion, if permitted by local physical conditions,
will drive fluids, petroleum or water, out of the larger openings
in the rocks more readily than from the smaller ones where
viscosity and capillarity tend to retain liquids. Relief of pres-
sure at any point or along any plane may result in the migration
of oil and water in front of the expanding gas. The result would
frequently be scattering of oil rather than concentration, but
upward movement would be favored, for relief of pressure
would more commonly come from that direction. Hence, here

20 R. H. Johnson, The role and fate of the connate water in oil and gas sands.
Am. Inst. Min. Eng., Bull. No. 98, pp. 221-226, 1915; Trans., vol. 51, pp. 587-
610, 1916.

182

KIRTLEY F. MATHER

is another cause tending toward the elevating of oil, if not toward
the top of any subterranean reservoir, at least toward the sur-
face of the earth.

Mills has recently^! called attention to the importance of the
escape of gas with entrained oil through fissures as a factor in
the migration and accumulation of oil in many faulted areas.
Both experimental and field data seem to indicate that ^^oil is
propelled more effectively than water by the propulsive force of
absorbed gas. Immediately upon the release of pressure,
the absorbed gas expands and propels the oil from within. The
comparatively high absorption capacity of oil and its tendency
to remain entangled with the flowing and expanding gas appears
to be largely responsible for this effective propulsion.’’ Such
migration of gas and oil in fault or other fissures ^Tas been up-
upward either to the surface or from one bed to another. Fis-
suring has also facilitated the lateral migration of oil and gas
through porous beds toward these points of escape.”

Earth movements; folding and faulting

The accumulation of strain within the earth’s crust may ex-
ceed the resisting strength of the strata and necessitate adjust-
ments by folding or faulting movement. In so far as these
adjustments involve decrease or increase of reservoir volume,
they may result directly in the transfer of oil or gas from place
to place. If similar folds^^ are formed, the beds will be com-
pressed and thinned on the limbs of anticlines and synclines,
but thickened and expanded on the crests and in the troughs of
the folds. The result will be a tendency toward the migration
of interstitial fluids from the place of compression to the places
of lesser pressure^ — the crest of an anticline or the bottom of a
syncline. The balance between folding movements competent
to cause such migration and those which w^ould cause regional
d^mamic alteration sufficiently complete to volatilize all the

R. Van A. Mills, Natural Gas as a factor in oil migration and accumulation
in the vicinity of faults, Bull. Am. Assoc. Petroleum Geologists, vol. 7, pp. 14-
24, 1923.

32 C. K. Leith, Structural Geology, Henry Holt & Co., New York, 1913, p. 106.

UNDERGROUND MIGRATION OF OIL AND GAS

183

lighter distillates from the petroliferous substances is, however,
so delicate that it is doubtful if folding movements have con-
tributed largely to the accumulation of oil in economic amounts.

Indirectly, folding and faulting of the earth’s crust may have
materially assisted in the migration and segregation of oil by
providing that element of motion which seems essential to the
effective operation of such motive forces as capillary action and
gravitative assortment. The frequency of earthquake vibra-
tions is suggestive of the repetition of jarring shocks which may
have operated to overcome adhesion and inertia which were
militating against gravitative assortment of oil and water.

Similarly, the development of fault fissures may afford chan-
nels for the escape of compressed gasses, and thus be the indirect
cause of migration and accumulation of oil impelled by expand-
ing gas, as noted in the preceding section.

Body tides

Regularly recurrent oscillatory movements within the body
of the earth are caused by the attraction of sun and moon.
Experiments undertaken to determine the rigidity of the earth
by tidal observations indicate^^ that the water tides are of much
less amplitude than they would be if the earth were absolutely
rigid, and that in fact three- or four-tenths of the tida] strain
is compensated by tides within the earth’s body. These move-
ments may be compared to the kneading to which a baker sub-
jects dough. They would in general result in an upward migra-
tion of earth fluids because as the liquids are squeezed out they
would move, if possible, in the direction of least pressure. This
kneading of the earth, like the less regular folding and faulting
movements, has probably been an important contributing cause
of oil and gas migration, notably assisting the operation of
other forces.

THE PROBABLE HISTORY OF MOST OIL AND GAS ACCUMULATIONS

Having thus reviewed the possible causes of the migration
of oil and gas, the probable history of the majority of the great

A. A. Michelson, Preliminary results of measurements of the rigidity of the
earth, Journ. GeoL, vol. 22, pp. 97-130, 1914.

184

KIRTLEY F. MATHER

commercial accumulations of these substances may now be
sketched. Variations in the relative importance of the different
factors involved may of course be expected because of the fact
that each oil or gas field is actually unique in its composite
features, but the general story needs only slight changes in its
major outlines to make it apply to most fields.

Distillation, at first dominantly biochemical and later domi-
nantly thermochemical, begins with the entombment of organic
matter in muds, clays and silts. With continued accumulation
of interstratified sandy and muddy layers, the oils and gases
thus formed are squeezed out of the finer into the coarser sedi-
ments. Differential capillary action draws water into the finer
openings while the volatile hydrocarbons move into the larger
ones. Thus, transverse migration from the shale birth-place of
petroleum to the reservoir sands and sandstones takes place.
Circulation of subterranean fluids and movements of the earth’s
body all contribute to this movement from one layer to an ad-
jacent one; whenever oil or gas enters coarsely porous portions
of the earth’s interior, completely enclosed by water-saturated
fine-grained rocks, there it must remain. Transverse migration
is never complete; the shales invariably retain more or less of
the petroleum which originates therein; it is more nearly com-
plete where there are several sandy layers interbedded at fre-
quent intervals within the shale series than where the same
amount of sand is concentrated into a single formation.

Oil and gas which enters coarsely porous strata, sandstones or
limestones, will move more or less completely to the pores above
those occupied by water within the reservoir. If the rocks are
saturated with water, differences in specific gravity, molecular
forces, ground water movement, etc., will lift the hydrocarbons
to the top of the reservoir and segregate them beneath fine-
grained strata or portions of strata. If the reservoir roof is
sufficiently inclined, the upward force will be resolved into
lateral movement which in most cases will be parallel to the
bedding of the rocks. This obliquely upward migration will be
stopped where the oil or gas is trapped by changes in the pitch
of the reservoir roof. Hence, a knowledge of the shape of the

UNDERGROUND MIGRATION OF OIL AND GAS

185

reservoir is a prime essential to wise exploitation of petroleum
accumulation. Ifj on the other hand, the reservoir is only
partly filled with water, oil should be accumulated above the
water surface, unless the pores are of capillary dimensions (for
oil) in which case it will be broadly disseminated through that
portion of the reservoir which is devoid of water. Hence,
knowledge of the water conditions and the porosity of the reser-
voir rocks are likewise of first importance to the petroleum en-
gineer. Lateral migration does not necessarily require an up-
ward component, especially if it is due to gas expansion, but,
because of the general prevalence of water in a more or less
static condition within the strata from which oil and gas are
obtained, it probably has nearly everywhere proceeded in an
obliquely upward direction. Its results in concentrating oil
and gas in certain parts of the reservoirs will depend chiefly upon
their shape.

1} 3 0-1

DENISON UNIVERSITY
BULLETIN

Volume XXIV, No. 5

Journal

OF THE

Scientific Laboratories

Valume XX

Articles 9-13

Pages 187 to 383

9. Trichoptilus pygmaeus Wlsm. and the Neuration of
the Family Pterophoridae. By A. W. Lindsey 187

10. Notes on American Paleozoic Cephalopods. By Aug.

F. Foerste 193

11. A Report on the Theory of Relativity (Einstein

Theory). By P. Biefeld 269

12. Some Problems of Taxonomy. By A. W. Lindsey 289

13. Notes on the Geology of Giles County, Virginia. By

George D. Hubbard and Carey G. Croneis 307

Subject and Author Index 379

GRANVILLE, OHIO

DECEMBER, 1924

The University Bulletin is issued bi-monthly and is entered at the
Post Office in Granville, Ohio, as mail matter of the Second Class

JOURNAI

OF THE

SCIENTIFIC LABORATORIES

OF

DENISON UNIVERSITY

Edited by

KIRTLEY F. MATHER

Permanent Secretary^ Denison Scientific Association^,
Granville, Ohio

The entire file of volumes 1 to 13 was destroyed by fire; no publications issued
prior to 1907 are now available. Volumes 14 to date may be obtained from the editor
at $2.00 per volume, with the exception of volume 15, the price of which is $1.00.
Separate parts, as listed below, may be purchased at the prices indicated.

VOLUME 14

Articles 1-5, pp. 1-60, Nov., 1908 $0.50

Pre-Wisconsin drift in the Finger Lake Region of New York ; F. Carney. 16 pp., 4 figs.

An esker group south of Dayton, Ohio; Earl R. Scheffel. 15 pp., 6 figs.

Wave-cut terraces in Keuka Valley, older than the recession stage of Wisconsin ice; F. Carney.

12 pp., 3 figs.

A form of outwash drift; F, Carney. 8 pp., 1 fig.

State geological surveys and practical geography; F. Carney. 6 pp.

Articles 6-10, pp. 61-188; April 1909 $1.00

Fossils from the Silurian formation of Tennessee, Indiana, and Kentucky ; Aug. F. Foerste.

56 pp., 4 plates.

Studies on babbit and other alloys ; 10 pp. J. A. Baker.

A statigraphical study of Mary Ann Township, Licking County, O. 28 pp., 15 figs. F. Carney.
Significance of drainage changes near Granville, Ohio; Earl R. Scheffel. 17 pp., 2 figs.

Age of the Licking Narrows ; K. F. Mather. 13 pp., 5 figs.

Articles 11-16, pp. 189-287; June, 1909 $0.75

A spectrometer for electromagnetic radiation; A. D. Cole. 10 pp., 6 figs.

The development of the idea of glacial erosion in America; F. Carney. 10 pp.

Preliminary notes on Cincinnatian fossils : Aug. F. Foerste. 20 pp., 1 plate.

Notes on Spondylomorum Quaternarium Ehrenb ; M. E. Stickney. 5 pp., 1 plate.

The reaction to tactile stimuli and the development of the swimming movement in embryos of
Diemyctylus torsus, Eschscholtz ; G. S. Coghill. 21 pp., 6 figs.

The raised beaches of the Berea, Cleveland, and Euclid sheets, Ohio. F. Carney. 25 pp., 5 figs.

Articles 17-18, pp. 289-442 ; November, 1909 $1.00

Preliminary notes on Cincinnatian and Lexington fossils ; Aug. F. Foerste. 45 pp., 6 plates.

The Pleistocene geology of the Moravia 'Qviadrangle, New York ; Frank Carney. 106 pp., 27 figs.

VOLUME 16

Article 1, pp. 1-100 ; March, 1910 — $1.00

Bulletin in commemoration of Clarence Luther Herrick.

TRICHOPTILUS PYGMAEUS WLSM.

AND

THE NEURATION OF THE FAMILY PTEROPHORIDAE

A. W. Lindsey

When “The Pterophoridae of America, North of Mexico’' was
published, two specimens of T. pygmaeus were available to the
authors, one in the collection of the United States National Mu-
seum and the other in the Fernald collection from the type lot.
It was gratifying, therefore, to receive from Mr. E. H. Blackmore
a series of ten specimens taken at Shawnigan, Vancouver Is.,
July 18, 1923. This is but one of many valuable results of Mr.
Blackmore’s diligent collecting and careful study for which the
writer expresses his hearty appreciation and thanks.

An examination of the specimens corroborated Mr. Black-
more’s identification. The opportunity which they furnish for
the accurate determination of the generic characters of Trichop-
tihis has apparently not been enjoyed by anyone else, excepting
possibly Lord Walsingham himself, for Professor Fernald had
not removed the wings from the single specimen now in his col-
lection, and there is no reason to believe that others exist where
they are available for scientific scrutiny. Mr. T. Bainbrigge
Fletcher (in litt.) states that he uses Buckleria Tutt for the other
species commonly placed in the genus, retaining Trichoptilus for
its type alone. His reason, ample, to be sure, is that Lord Wal-
singham compared the species concerned and agreed with his
views. In order to settle this point, the right wings of one speci-
men were removed and mounted for microscopic examination,
and this led to the surprising results here recorded.

The first wings prepared showed only a single long vein run-
ning to the tip of the second lobe of the primaries, apparently
M.+CUi, according to later discoveries. They were otherwise
similar to those of T. lohiclactylus Fitch excepting the evanescent
tips of R2 and R^ and bases of both anals. The complete loss of a
vein from the second lobe seemed to justify the separation of the
genera as practiced by Mr. Fletcher, but to my surprise, other

187

188

A. W. LINDSEY

specimens showed variations in neuration. One had Cug well
marked, tubular, though weak, but this specimen lacked R^.
Other wings were then examined which showed no trace either
of Ri or Cu^. The figure (Text fig. 1) is therefore a composite
showing all veins known to appear in this species. It will be
seen that it differs so little from the wings of other species now

FIG. 1. TRICHOPTILUS PYGMAEUS WLSM NEURATION.

included in the genus (Plate XX, fig. 1) that the retention of the
present association is justified. The condition of the neuration
indicates, however, that pygmaeus is in a state of evolution which
may ultimately produce a much simpler wing than is now found
in the species.

In consideration of the diversity of genitalic structure ex-
hibited by the North American species, no analysis of relation-
ships can be drawn from this source. The genitalia of pygmaeus
are figured (Text fig. 2) for specific identifications. The figure
is taken from a camera drawing of a prepared specimen which
was slightly distorted on the slide. No appreciable asymmetry is
actually present.

It occurred to the writer while working on the wings of this
species that the neuration of the Pterophoridae as treated by
Meyrick in the Genera Insectorum and by Barnes and Lindsey
in the Pterophoridae of America is probably incorrectly inter-
preted. Our North American genera furnish enough types of
neuration to illustrate the problem nicely, and Plate XX, a re-

TRICHOPTILUS PYGMAEUS

189

production of Plate XLVIII of the Pterophoridae of America;
shows examples of each genus. The writer is indebted to Dr.
Wm. Barnes for the use of the cut for this plate.

In Fig. 10 are shown the wings of the only North American
species without clefts. It will be noted that Rg reaches the apex

of the primaries, and M. are weak, M3 and CUi are long
stalked, and 1st and 2nd A vestigial. This suggests that some
veins may be lost by independent reduction and others by pro-
gressive anastomosis, as is so often the case in the Lepidoptera.
In the secondaries vestigial veins are even better illustrated, and
one median, probably M2, is completely lost.

The problems suggested by the comparison of wings of the
cleft-winged genera are mostly simple. M^ and Mo are usually
faintly evident as thickened lines at the base of the cleft in the
primaries, and in Oidaematophoriis alone of our genera is one of
them, M,, tubular. M. persists, showing a tendency to stalking
with CUj. In no example is there evidence of extreme coalescence
of these veins which would suggest incipient coincidence. On the
contrary Adaina shows both GUj and CUg in a vestigial state, in-
dicating the limitation of coalescence of the former with Mg and
the reduction of both cubital branches by independent change.
Unfortunately none of our genera in the Oidaematophorid series
(Spuler's Pterophorinae) , including the genera with two anals in
the secondaries, appear to be derived from this genus, so the
possible results cannot be followed out. In the remaining genera

190

A. W. LINDSEY

there is nothing to show the fate of the cubitals except several
degrees of stalking of Cu^ and M3, the complete loss of one branch
in THckoptilus, and the complete or partial loss, by independent
reduction, of the remaining branch in T. pygmaeus Wlsm.

The radius of the primaries is the one o-ther vein whose history
is complex. The fact that its fifth branch runs to the apex of the
wing in Agdistis but ends behind the apex in all of the cleft-
winged genera where it is indubitably present, suggests funda-
mental separation of these lines, as has long been the writer’s
view. A significant fact regarding this vein is that no genus re-
taining five branches of the radius has the fifth stalked with an-
other, although the third and fourth are frequently stalked, (and
the second with them in some specimens of Pselnophorus heU
fragei Fish, with only four branches remaining) . In the genera
retaining only four branches of the radius, several things may be
noted. First, when the posterior branches are stalked, the most
posterior ends in the apex of the wing, both conditions suggest-
ing that it is R4 or a complex including this vein. Second, when
the most posterior branch of the four is not stalked, it ends be-
hind the apex, and excepting Oidaematophorus , is preceded by
stalked branches, both conditions suggesting that it is R5. Third,
when R5 as thus interpreted is present, it appears that the pro-
gressive anastomosis of Ro, Rr. and R^, actually visible in a series
of P. belfragei Fish, has resulted in the coincidence of two
branches. These would naturally be the two showing the earliest
and most prevalent tendency to unite, viz., Rg and R4, and the vein
ending in the apex of the primaries must be Rg+i- This is. a
condition such as seen in the wings of Pterophorus periscelidac-
tylus Fitch. (Fig. 2)

In T. pygmaeus Wlsm. three radial branches at the most are
present, and the first two show partial reduction without stalk-
ing. Apparently then both R4 and Ro may be lost in this way.
The writer’s previous association of the genus, phylogenetically,
with Pterophorus (Oxyptilus) cannot stand, since in the latter
Ro is invariably stalked. Meyrick’s diagnosis of Trichoptilus
states, however, that Ro may be stalked. This would indicate
that some of the exotic species, not available to the writer for ex-
amination, represent a different line of evolution which may
properly be derived from Pterophorus (Oxyptilus) .

The condition of the veins in some of the more specialized
genera, of which Aciptilia is the most extreme, is one which can-

TRICHOPTILUS PYGMAEUS

191

not be satisfactorily interpreted without studies of the trachea-
tion of pupal wings. The single vein in the first lobe of the pri-
maries of this genus may be II2+3+4J with independently lost,
or R3+4 with both and Rg independently lost.

This interpretation of neuration together with the characters
found in other parts of the body modifies the writer's former
opinions of the phylogeny of the North American genera as ex-
pressed in the Pterophoridae of America (Diagram, p. 286). In
addition to actual differences between existing genera, it now
seems unlikely that so many of these genera represent the an-
cestry of others. Rather than this, they seem to be derived from
com.mon ancestors in most cases. The following diagram ex-
presses the writer's modified view of the phylogeny of our genera.

ACIPTILIA

TRICHOPTILUS

PTEROPHORUS

PLATYPTILIA

EXELASTIS

ADAINA

PSELNOPHORUS

OIDAEMATOPHORUS

MARASMARCHA

STENOPTILIA

AGDIS^nS

In order to correct the inaccuracies which crept into the key
to North American genera in the Pterophoridae of America, the
following key has been prepared. It has been found impossible
to construct a key without falling back on neuration at some
point, therefore it has been used freely to produce an accurate
key. The wings may easily be examined as transparent objects
without denuding or bleaching if they are mounted in pure al-
cohol on a microscope slide, and all veins and thickened lines then
become visible.

192

A. W. LINDSEY

KEY TO THE NORTH AMERICAN GENERA
OF PTEROPHORIDAE

1. Wings entire ....^.Agdistis

Wings cleft 2

2. Radius of primaries with four branches or less 3

Radius of primaries with five branches 10

3. Primaries with only one or two veins in second lobe, anals ex-
cepted; deeply cleft, with slender lobes 4

With Ms, Cui and Cus all present 5

4. Two or three branches of radius present .....Trichoptilus

Only one radial .....Aciptilia

5. Primaries with all branches of radius free Oidaematophorus

Some branches stalked 6

6. With a free vein (Rs) behind the stalked branches of the radius,

ending behind apex of first lobe 7

The last branches of the radius stalked Pselnophorus

7. Secondaries with a tuft of black scales near tip of third

feather Pterophoms

No such tuft 8

8. Second lobe of secondaries with two veins Adaina

With three veins 9

9. Fringes of inner margin of third lobe of secondaries with a few

scales, sometimes faint in our species Exelastis

Without such scales Marasmarcha

10. Ro, Rs and Ri stalked Pterophorus

Ra and Ri alone stalked 11

11. Secondaries usually with black scales in fringes of inner margin.

Anal angles of both lobes of primaries usually prominent Platyptilia

Without black scales. Anal angles present but retreating Stenoptilia

PLATE XX

Neuration of Pterophoridae.

1. Trichoptilus lohidactylus Fitch.

2. Pterophorus peris celidactykis Fitch.

3. Platyptilia carduidactyla Riley,

4. Pselnophorus belfragei Fish.

5. Adaina zephyria B. <& L.

6. Aciptilia walsinghami Fern.

7. Oidaematophorus lithodactylus Tr.

(Genotype, European)

8. Marasmarcha pumilio Zell.

8a. Exelastis cervinicolor B. & McD.

(First lobe of primary)

9. Stenoptilia pterodactyla lArm. (Genotype).
10. Agdistis americana B. & L.

Journal Scientific Laboratories Denison University Vol. XX

PLATE XX

A. W. LINDSEY

XEURATION OF PTEROPHORIDAE

NOTES ON AMERICAN PALEOZOIC CEPHALOPODS
Aug. F. Foerste

INTRODUCTION

The writer has been engaged for a number of years on an in-
tensive study of Ordovician and Silurian cephalopods with special
reference to those of American origin. The study is far from com-
plete. A large quantity of the available material has not yet been
examined, and some of that already studied must be re-examined
in the light of later observations. Research of this sort is greatly
expedited by the helpful criticism of others interested in the
same field; but in the absence of published reports of progress,
such assistance is limited to that secured at occasional meetings.
Moreover, it is desirable to reduce to printed form some of the
results thus far obtained, in order that they may be available for
use in other studies. The following notes are accordingly a mis-
cellaneous gathering, in part intended to invite criticism, and in
part intended to report progress, especially along the line of
generic relations.

The conclusion has been reached that Ozarkian and Canadian
cephalopods were largely holochoanitic in structure and that the
first ellipochoanoidal cephalopods were of Chazyan age. In holo-
choanoidal cephalopods the septal necks extend downward so that
each is in contact with the upper margin of the neck beneath, into
which it invaginates without connecting ring or sheath. The
septal necks of ellipochoanoidal cephalopods are short, and suc-
cessive necks are connected by ring-like segments, called con-
necting rings or sheaths. Frequently these connecting rings
have failed of preservation and then only the unconnected septal
necks may be seen. In other specimens, especially those of Acti-
noceroids, the septa likewise are wanting, but the siphuncle re-
mains, reinforced by interior calcareous deposits.

Certain species of cephalopods almost or quite invariably lack
all trace of connecting rings. Probably in these species the mem-
brane which ordinarily secreted the calcareous material either
formed only a very thin deposit or none at all.

193

194

AUG. F. FOERSTE

Such holochoanitic genera as Encloceras, Camerocey^as and Pilo-
ceras have siphuncles built by successive septal necks which ex-
tend downward until each invaginates into the neck next beneath.
Within the camerae this type of neck generally has a concave
vertical outline. The septal necks of Clarkoceras, Eremoceras,
Ellesmereoceras and Protocycloceras^ have vertical outlines simi-
larly concave. Ruedemann has shown corresponding structures
in Protocycloceras, Orygoceras and Cyclostomiceras.^ A recent
examination of all the orthoconic and crytoceraconic species de-
scribed by Billings from the Canadian, indicates that concave
vertical outlines prevail in all the specimens which reveal the
structure of the siphuncle. The typical Black River form of
Cyrtocerina has an ellipochoanoidal structure, but the siphuncle
of the Canadian species Cyrtocerina mercurius, presents seg-
ments with concave vertical outlines, thus indicating that it is
really a Clarkoceras. In the numerous species of '' Orthoceras”
described by Billings, concave vertical outlines prevail along the
segments of the siphuncle within the camerae.

Apparently the structure of the Canadian orthocones and cyr-
toceracones is prevailingly that of the holochoanitic cephalopods.
Corresponding ellipochoanoidal genera make their appearance
in Chazyan time, though such holochoanoidal genera as Endoceras
continue through that epoch into later stages. If these observa-
tions are verified by increasing knowledge of Ozarkian and Ca-
nadian cephalopods, they would suggest that the interval between
the Canadian and Chazyan stages was one of the most important
in geologic history, sufficient to admit of a major change in the
structure of cephalopods. If corresponding changes are found in
other groups of animals, contrasting those of Canadian age with
those of Chazyan and later times, the separation of Canadian
strata from the Ordovician system would seem as fully warranted
by paleontology as by stratigraphy.

The enormous number and variety of species which have been
referred to the genus Orthoceras has always been a serious prob-
lem to the systematist. Barrande grouped his numerous species
into various divisions based on surface ornamentations. Hyatt
has proposed generic names for the major groups. Later, Hyatt

^ Foerste, A. F., Notes on Arctic Ordovician and Silurian cephalopods;
Journ. Sci. Lab. Denison Univ., vol. 19, pp. 261-271, 1921.

^ Ruedemann, R., Cephalopoda of the Beekmantown and Chazy formations
of the Champlain basin; New York State Museum Bull. 90, pp. 444, 451,
502, 1906.

AMERICAN PALEOZOIC CEPHALOPODS

195

attempted in Zittel-Eastman's Text-book of Paleontology to in-
troduce diagnostic characters based on internal structure, but
apparently without any considerable degree of success.

Although the generic names introduced by Hyatt have proved
very convenient in the past, it is now evident that dissimilar
groups are in some cases included under a single generic heading,
so that it is probable that further subdivision of this genus is
desirable. Before this is done, however, the types of the genera
previously proposed must be studied with the view of determin-
ing the proper limits to assign to those genera in restricting or
subdividing them. Here there are several difficulties. It is prac-
tically impossible to determine what species forms the real type
of Orthoceras, nor is the interpretation of Cycloceras clear.
Moreover, the genera Geisonoceras, Daivsonoceras and Spyro-
ceras, proposed by Hyatt, must be interpreted from the original
type species and not as redefined by Hyatt in the Zittel-Eastman
Textbook.

Similar statements apply to the different subdivisions which
have been proposed for the genus Actinoceras. The name Sacto-
ceras, established with a Silurian species for its type, should
probably not be discarded for Loxoceras, based on a Carbonifer-
ous species.

Looking toward a clearer understanding of these cephalopods,
the new genus, Perigrammoceras, is here proposed to accommo-
date certain orthoceroids, and a new subdivision of Actinoceras
is given the generic name, Elrocloceras. The familiar species
Trochoceras (?) baeri is made the type of another new genus,
Charactoceras.

The many species ordinarily assigned to the genus Oncoceras
are apparently divisible into two groups, one of which is typified
by 0. pandion Hall, while the other is the true Oncoceras with
0. constrictum Hall as its type. For the 0. pandion group the
name Beloitoceras is proposed. It was apparently from Beloito-
ceras that Maelonocey^as was evolved. Either Beloitoceras should
be considered an independent genus or it should be made a sub-
division of Maelonoceras. But if the second alternative is chosen,
Maelonoceras must be used in a broader sense than the customiary
interpretation based on the genotype, M. praematurum.

Another group of conchs, sometimes included in Oncoceras, is
typified by the species originally described as Cyrtoceras orcas

196

AUG. F. FOERSTE

Hall. C. laterale and C. orodes are closely similar species. For
these the term Amphicyrtoceras is proposed. Among other forms
having about the same characteristics are Oncoceras futile Bil-
lings, O. pettiti Billings and 0. teucer Billings. Streptoceras dif-
fers from Amphicyrtoceras chiefly in the more triangular out-
line of the aperture due to the anterior extension of the hypo-
nomic sinus into a sort of lip. It probably was derived from the
latter genus. Poterioceras is unknown in Silurian strata.

Among gomphoceroid conchs, there is a primitive group, known
to be represented in the Richmond and probably present also
in earlier strata, which has only a moderate angulation at the
hyponomic sinus instead of a strong constriction as in typical
GompJioceras. For this group the term Diestoceras is proposed,
with G. indianense as the genotype. This genus also includes
G. obesum Billings and G. eos Hall and Whitfleld.

Finally, the generic terms Westonoceras and Cyrtogomjoho-
ce7^as are here proposed for the very aberrant species, Cyrtoceras
manitobense Whiteaves and Oncoceras magnum Whiteaves.

ACKNOWLEDGEMENTS

It is needless to state that it would have been impossible to
carry on the studies included in the present publication if it had
not been for the good will and generous helpfulness shown by
many individuals. I am especially indebted to Dr. R. S. Bassler
of the U. S. National Museum ; Dr. E. M. Kindle of the Victoria
Memorial Museum; Prof. Percy Raymond and Mr. Samuel Hen-
shaw of Harvard University; Dr. Chester A. Reeds and Dr. E. 0.
Hovey of the American Museum of Natural History ; Prof. J. E.
Carman of Ohio State University ; Prof. Stuart Weller and Mr.
Arthur W. Slocom of the University of Chicago; Mr. Henry L.
Ward of the Public Museum of Milwaukee ; Prof. W. H. Shideler
of Miami University; Mr. C. L. Faber of Cincinnati, and Judge
Henry Pavey, now deceased, of Hillsboro, Ohio. Without as-
sistance from these individuals, and the loan of specimens from
collections under their care, little of permanent value could have
been accomplished.

I am under special obligations to Dr. David White and Mr.
Walter C. Mendenhall, of the U. S. Geological Survey, for access
to the facilities of that Survey, and for giving me every en-
couragement.

AMERICAN PALEOZOIC CEPHALOPODS

197

1. THE HOLOCHOANITIC CEPHALOPODS OF CANADIAN STRATA

Ulrich included in the Canadian series of strata the Beekman-
town of New York, Vermont, and adjacent Canada, the Levis
of the Quebec area, the Romaine of the Mingan island area, all
but the basal part of the Bretonian of Nova Scotia, the upper
part of the Quebec group of Newfoundland, and the approxi-
mate equivalent of these strata elsewhere. Those strata which
intervene between the Canadian and the typical Cambrian he
included in the Ozarkian. The fauna of the Potsdam standstone
is regarded as distinct from the typical Cambrian and as char-
acterizing the basal part of the Ozarkian.

The cephalopod fauna of the Ozarkian and Canadian differs
so strongly from that of the overlying Ordovician that it sug-
gests that the interval between the Canadian and the Ordovician
is one of the great time-breaks of geology. Very few genera
bridge the interval between the Canadian and Ordovician, and
these few are represented in the Ordovician by species which
usually are strikingly different from those in the Canadian.

Such genera as Eurystomites, Tarphyceras, Aphetoceras and
Trocholitoceras are, strictly speaking, Canadian. It is possible
that an intensive study of Eurystomites plicatus and Eurysto-
mites rohertsoni will reveal differences from the typical Ca-
nadian forms of sufficient importance to be at least of subgeneric
rank. In Eurystomites plicatus, for instance, the segments of
the siphuncle enlarge slightly within the camerae, as though
short septal necks with intermediate connecting rings were pres-
ent, while this appearance is not noted in Canadian species. In
Tarphyceras multicameratum, moreover, the camerae are much
shallower and the rate of increase in diameter of the conch is
greater. Nothing corresponding to the Canadian species of
Schroederoceras occurs in the Ordovician of North America.
Typical Schroederoceras, of course, is European, 8 European
species being recognized by Hyatt. Typical Trocholites is of
Trenton or Cincinnatian age, but Trocholites internistriatus
(Whitfield) occurs as early as the Beekmantown division of the
Canadian.

The Canadian species described by Ruedemann under the term
Cyrtendoceras (?) priscum differs from anything known in the
Ordovician of America.

Canadian as well as Ordovician and Silurian species have been

198

AUG. F. FOERSTE

referred to the genera Cyclostomiceras, Cyrtocerina, and Mae-
lonoceras, but the Canadian species so referred belong to dif-
ferent genera from those occurring in later strata. In typical
Cyclostomiceras , of Canadian age, the segments of the siphuncle
present concave vertical outlines, while the Niagaran species
Cyrtoeras hrevicorne Hall and Cyrtoceras orodes Billings, re-
ferred by Grabau and Shimer to Cyclostomiceras, belong to a
distinct genus with short septal necks and convex connecting
rings, for which the term Amp hicyrtoc eras is proposed on the
following pages. Cyrtoceidna typica Billings, from the Black
River, has nummuloidal segments in the siphuncle (Plate XLI,
Fig. 9) while in Cyrtoce^dna mercurius Billings these segments
present concave vertical outlines (Plate XLI, Fig. 8) as in Clark-
oceras, a genus which seems to be confined to the Canadian. In
Maelonoceras praematurum (Billings), from the Black River,
the segments of the siphuncle are subfusiform, while in Cyrto-
ceras metellus Billings, from the Canadian, these segments are
strongly nummuloidal in form, if specimen No. 820a in the Vic-
toria Memorial Museum correctly represents this species.

Such genera as Eremoceras and Piloceras are confined to the
Canadian. In both, the segments of the siphuncle have concave
vertical outlines within the camerae.

Concave vertical outlines are presented also by a considerable ^
number of those orthoconic shells which were described by Bill-
ings and others from Canadian strata under the generic term
Orthoceras. In fact, all of the Canadian orthoconic species, con-
cerning which it has been possible to learn the structure of the
siphuncle, have siphuncular segments with concave vertical out-
lines. Of these, the annulated forms are, at present, referred to
Pj^otocycloceras. Possibly most of the smooth forms will fall
under Ellesmereoceras.^ They are characterized, as a rule, by
rather closely arranged septa and by siphuncles of more moderate
size than in typical Eiidoceras. Orthoconic specimens, with
siphuncles more readily comparable with those of typical En-
doceras, also exist in Canadian strata. In none of the Canadian
Endoceroid specimens described by Billings has it been possible
to discover the presence of endocones. From this it does not
follow necessarily that endocones are absent, since the actual

® Foerste, A. F., Notes on Arctic Ordovician and Silurian cephalopods;
Journ. Sci. Lab. Denison Univ., vol. 19, p. 265, pi. 27, figs. 3A, B, C; pi. 33,
fig. 3, 1921.

AMERICAN PALEOZOIC CEPHALOPODS

199

number of specimens which expose well the interior of the si-
phuncle is relatively small. However, when the genus Ellesmereo-
ceras was described, the absence of endocones was regarded as
one of its characteristic features.

Orygoceras is another orthoconic Canadian genus with si-
phuncular segments presenting concave vertical outlines. The
conch displays a smooth exterior, but an annulated interior.

Canadian cephalopods are remarkable for the number of
genera and species in which the segments of the siphuncle .pre-
sent concave vertical outlines. Such outlines are characteristic
of the holochoanitic cephalopods, in which the septal necks are
prolonged downward at least the height of one of the camerae.

In Zittel-Eastman’s Text-book of Paleontology the Holochoan-
ites include the genera Vaginoceras, Cameroceras, Endoceras,
Narthecoceras, Nanno, Piloceras, and Cyrtendoceras. To this
list the genera Cyclendoceras and Clarkoceras have been added
by Bassler.^ Ruedemann recognized the holochoanitic structure
of the siphuncle of Protocycloceras,^ his illustrations show the
concave vertical outlines of the siphuncular segments of Cyclo-
stomiceras. His vertical section of Orygoceras indicates a
similar structure. The present writer has described the concave
vertical outlines of the siphuncular segments of Eremoceras and
Ellesmereoceras, and in the present bulletin he calls attention to
similar structure in various orthoconic cephalopods described by
Billings from Canadian strata.

Although it does not follow necessarily that species with si-
phuncular segments having concave vertical outlines are holo-
choanoidal in structure, the writer believes that such a relation-
ship exits. Should this prove to be true, after further investiga-
tion, then it follows that the chief characteristic of Canadian or-
thoconic and cyrtoconic cephalopods is the remarkable dominance
of holochoanitic forms.

Although such holochoanitic genera as Cameroceras, Cyclen-
doceras, Endoceras, Narthecoceras, Nanno, Suecoceras, and
Vaginoceras are well represented in Ordovician strata, they here
are associated with numerous Orthochoanitic and Cyrtochoanitic
forms which are either rare or absent in Canadian strata. The

^ Bassler, R. S., Bibliographic Index of American Ordovician and Silurian
fossils; U. S. Nat. Museum Bull. 92, 1915.

® Ruedemann, R., Cephalopoda of the Beekmantown and Chazy forma-
tions of the Champlain basin; New York State Museum Bull. 90, p. 441, 1906.

200

AUG. F. FOERSTE

Canadian, in brief, is characterized by the dominance of holo-
choanitic cephalopods, and the early Ordovician by the influx of
numerous Orthochoanitic and Cyrtochoanitic cephalopods.

It should be noted that in some of the Canadian genera of
cephalopods, here cited as having concave vertical outlines, this
concavity is so faint that their outlines are described more
readily as straight than concave ; but they are distinctly not con-
vex. This is true, for instance, of the species originally described
as Cyrtoceras quebecense.

2. SMOOTH ORTHOCONIC CANADIAN CEPHALOPODS

Most of the smooth orthoconic cephalopods found in the Ca-
nadian strata in Canada have the siphuncle in contact with the
ventral wall of the conch. The sutures of the septa of Orthoceras
sordidum Billings curve downward distinctly on the ventral
side of the conch, as in the specimen figured by Ruedemann® from
Fort Cassin, Vermont, under the name Endoceras montrealense.
The septal necks extend downward the length of one camera
and present a concave vertical outline within the camerae. Simi-
lar septal necks are found in Orthoceras montrealense Billings
and Orthoceras glaucum Billings. These species are alike in the
small height of their camerae. In this respect they resemble
Ellesmereoceras scheii Foerste, to which they miay be closely
related.

In Orthoceras indagator Billings the structure of the siphuncle
is more like that of typical Endoceras. While the general ver-
tical outline of the septal necks is concave within the camerae,
the lower end of these necks curves inward to invaginate within
the upper part of the neck next beneath. The upper part of the
siphuncle of one specimen, numbered 7454 in the Victoria Me-
morial Museum, appears to contain an endocone. Apparently
Orthoceras ind.agator is one of the earliest known forms of typi-
cal Endoceras , a genus common in the Chazyan.

Nothing is known of the structure of the septal necks in Ortho-
ceras sayi, O. autolycus, 0. veterator or 0. perseus, all described
by Billings from Canadian strata, with the possibility of
0. autolycus having been derived from Ozarkian strata, since it
occurs in conglomeratic layers. Of these species, Orthoceras sayi
has such a large siphuncle that it resembles typical Endoceras in

® Ruedemann, R., op. cit., p. 424.

AMERICAN PALEOZOIC CEPHALOPODS

201

transverse sections. In the other three species the siphuncles are
relatively smaller and the camerae are closely crowded, as in
Ellesmereoceras. It will require vertical sections of the types to
determine their affinity with any confidence.

The siphuncle of Orthoceras atticus, 0. becki and 0. explorator,
all described by Billings from Canadian strata, is not in contact
with the ventral wall of the conch, but is between the ventral
wall and the center. The siphuncle of 0. atticiis was described
by Billings as '‘not much, if at all, inflated between the septa.”
That of 0. explorator is described as cylindrical. In none of the
three species is the structure of the siphuncle known with suffi-
cient accuracy to determine whether it belongs to the group with
long septal necks, as in the Endoceroids, or to the group with
short septal necks, as in the Orthoceroids.

So far, no orthoconic cephalopods have been found in Canadian
strata of which it is known with certainty that they belong to the
Orthoceratida rather than to the Endoceratida. On this account
it would be desirable to investigate all known Canadian ortho-
conic species with the object of determining the structure of their
siphuncles. It is evident that if typical Orthoceratida should
prove absent in Canadian and Ozarkian strata, this fact would be
of great service in identifying the horizon of some of the lower
Paleozoic formations.

The single specimen of Orthoceras primigenium, figured by
HalT from the Canadian near Fort Plain in the Mohawk valley of
New York, has a conch estimated to have been about 18 or 19 mm.
in diameter at its lower end, enlarging possibly to 22 mm. at its
upper end. A thickness of only 2 to 3 mm. of one side of the conch
remains. There is no trace of annulation of the surface of the
shell. The specimen consists of a living chamber 14 mm. in
height above the suture of the uppermost septum. On the left
margin of the specimen 12 camerae occur in a length of 9 mm.
The two uppermost camerae are distinctly shallower than those
beneath, suggesting that the conch had reached full maturity.
The concavity of the septa along that part of the specimen which
is preserved equals 2 mm. ; evidently toward the center of the
original specimen this concavity must have been much greater.
There the specimen in its present condition is 13 mm. in width,
the maximum concavity is 4.5 mm. from the left side, and the

’ Hall, J., Pal. New York, vol. 1, 1847, pi. 3, fig. 11.

202

AUG. F. FOERSTE

septa rise 2.5 mm. higher on the right side than on the left. This
indicates that the sutures of the septa are oblique, and that the
siphuncle probably was located naarer the left side of the speci-
men, somewhere in that part which has weathered away. On the
right side of the specimen the septa are more closely crowded,
suggesting that, notwithstanding the general orthoconic aspect
of the specimen, it may have been somewhat cyrtoconic in struc-
ture. There is no evidence that this single specimen is even con-
generic with the small apical ends of orthoconic shells figured by
Hall on the same plate (Fig. 11a).

3. ELLESMEREOCERAS FOERSTE

Genotype: Ellesmereoceras scheii Foerste. Journ. Sci. Lab., Denison
Univ., vol. 19, p. 265, pi. 27, fig^s. 3 A, B, C.; pi. 33, fig. 3, 1921

The genus Ellesmereoceras was founded on the belief that there
was a group of Endoceroids in which endocones we.re absent. If
eventually it should be proved that endocones were present, the
value of this generic term would be questionable. In most of the
species having the general appearance of Ellesmereoceras the
vertical outlines of the septal necks are distinctly concave, but
there is no clear evidence of the invagination of the lower part of
these necks into the upper part of the neck next beneath, as in
typical Endoceras. The camerae usually are closely crowded.

This type of structure appears to be characteristic of Canadian
strata, but may have originated in Ozarkian times.

Holochoanitic cephalopods with endocones are known to be
present in the Ozarkian, and are under investigation by Dr. E.
0. Ulrich.

4. PROTOCYCLOCERAS HYATT

Genotype: Orthoceras lamarcki Billings. Canadian Nat., vol. 4, 1859,
p, 362; Foerste, Journ. Sci. Lab. Denison Univ., vol. 19, 1921,
p. 268, pi. 33, figs. 7 A-D

Protocycloceras was established by Hyatt to include annulated
orthoceracones and cyrtoceracones without longitudinal ridges
but with a large siphuncle.

Ruedemann has shown® that in Orthoceras lamarcki, the geno-
type, the septal necks have a length equal to that of one camera,
and that within the camerae their vertical outlines are concave.
He has also figured a similar structure in Protocycloceras whit-

® Ruedemann, R., op, cit., p. 440.

AMERICAN PALEOZOIC CEPHALOPODS

203

fieldi Ruedemann.^ Orthoceras ordino.tu7n Billings likewise pos-
sesses septal necks with concave vertical outlines within the
camerae. In the three species here named the siphuncle is not in
contact with the ventral wall of the conch. In all the other an-
nulated orthoconic species described by Billings from Canadian
strata, contact of the siphuncle with the ventral wall of the
conch prevails.

Nothing is known about the siphuncle of Orthoceras catulus,
0. fiirtivum, and 0. repens, beyond the fact that its general form
is cylindrical, and that it is in contact with the ventral wall of the
conch. All are Canadian species, described by Billings.

In Orthoce7^as cataline, 0. xerxes, and 0. cato, also described by
Billings from Canadian strata, the conchs are not only annulated
but also striated transversely. In all three of these species
the septal necks are distinctly concave within the camerae. Trans-
verse striae were not discovered on any of the other Canadian
annulated orthocones mentioned in the preceding paragraphs.

In Orthoceras henrietta Dwight the conch is strongly annu-
lated. The siphuncle is nearly in contact with the ventral wall
and is 1 mm. in diameter where the diameter of the conch is
6.4 mm. .

Apparently all of the above species are to be included in Pro-
to cy do ceims.

5. ORYGOCERAS RUEDEMANN

Genotype: Orthoceras cornuoryx Whitfield. Amer. Mus. Nat. Hist. Bull.,

1, 1886, p. 320, pi. 27, figs. 1, 2, 6; Ruedemann, New York State Mus.

Bull., 90, 1906, p. 450, pi. 14, figs. 5-8, text fig. 19, 20

Orygoceras is described as consisting of conchs which are
smooth externally but which internally are annulated. The si-
phuncle is small and is almost 1 mm. from the ventral wall of the
conch. Ruedemann describes the siphuncle as orthochoanitic, the
septal necks being short and straight and the remainder of the
siphuncle being formed by the intervening connecting sheaths.
In his figure,^® the vertical outline of the segments of the si-
phuncle included within successive camerae is seen to have been
concave. His section passes through the center of the siphuncle
in a lateral direction.

® Idem, p. 444, figs. 17a, b.

Idem, p. 451. fig. 20.

204

AUG. F. FOERSTE

6. CLAR-KOCERAS RUEDEMANN

Genotype: Piloceras newton-winchelli Clarke, Geol. Minnesota, vol. 3,
pt. 2, 1897, p. 767, figs. 8, 9; pi. 47, figs. 1-3. Ruedemann, New
York State Mus. Bull., 80, 1905, p. 337

Clarkoceras proclaims its relationship to the suborder Holo-
choanites not only by the presence of endocones but also by the
concave outline of the segments of the siphuncle within the
camerae. The septal necks apparently extend the length of one
camera. Excellent figures of the structure of the genotype are
presented by Clarke. The siphuncle is free from contact with
the adjacent wall of the conch.

Clarkoceras holtedahli Foerste,^^ from the Canadian of Bache
peninsula on Ellesmereland, evidently is congeneric. Here also,
the elongated septal necks present concave vertical outlines with-
in the camerae, as in Piloceras. The siphuncle is almost in con-
tact with the adjacent wall of the conch.

A similar structure is displayed by the species Cyrtocerina
mercurius Billings (Plate XLI, Fig. 8), described from the Ca-
nadian at Point Lewis, opposite Quebec, This species is related
to, but is not congeneric with Clarkoceras.

Typical Cyrtocerina (Plate XLI, Fig. 9), however, as repre-
sented by its genotype Cyrtocerina typica Billings, from the
Black River (Leray) at Pauquette Rapids, Ottawa river, Canada,
belongs to the group Ellipochoanida, as originally defined by
Hyatt. This group included both the suborder Orthochoanites
and Cyrtochoanites as defined later in Zittel-Eastman’s Textbook
of Paleontology. Judging from the convex curvature of the seg-
ments of the siphuncle within the camerae, the relationship of
typical Cyrtocerina is with the Cyrtochoanites.

Among the various species described by Billings from the Ca-
nadian strata of Canada under the name Orthoceras, there are
two which evidently are related to Clarkoceras, although their de-
gree of relationship can not be determined until the conch, as a
whole, is known. These species are Orthoceras missiquoi and
Orthoceras edax.

In Orthoceras missiquoi the siphuncles are slightly curved,
especially toward the apical end. That side of the siphuncle
which is concavely curved lengthwise is smooth and a little flat-

” Foerste, A. F., op. cit., pi. 27, figs. 2A, B; pi. 33, fig, 1.

“ Hyatt, A,, Genera of fossil cephalopods; Boston Soc. Nat, Hist., Proc.,
vol. 22, p. 260, 1883.

AMERICAN PALEOZOIC CEPHALOPODS

205

tened and evidently was in contact with the ventral wall of the
conch, so that the location of the siphuncle must have been endo-
gastric, as in Clarkoceras. Along the remainder of the contour
of the siphuncle the septal necks appear to have equalled in
length the height of the camerae, and to have presented vertical
outlines within these camerae. In one of the specimens an
endocone apparently was present. Orthoceras edax shows a
similar structure. Both Orthoceras missiquoi and 0. edax are
congeneric with Cyrtoceras quebecense Whiteaves, described
from Point Lewis, opposite Quebec. The conch of the latter
species is relatively much more elongated than in typical Clarko-
ceras; the segments of the siphuncle are cylindrical in form, and
consist of the septal necks, each of which is one camera in length.

7. EREMOCERAS (HYATT) FOERSTE

Genotype: Cyrtoceras syphax Billings. Pal. Foss., vol. 1 ,Geol. Surv.

Canada, 1865, p. 194, text fig. 178, Foerste, Journ. Sci. Lab.

Denison Univ., vol. 19, 1921, p. 263, pi. 33, figs. 8 A, B. C; 2

Eremoceras is a small subfusiform cephalopod, somewhat like
Cyclostomiceras in form. The dorsal side of the conch is dis-
tinctly convex lengthwise, while the ventral side is almost
straight. The camerae are closely crowded. The siphuncle is
large, and endogastric in location. It is in contact with the ven-
tral side of the conch for the greater part of its width. In the
type specimen, the siphuncle is depressed dorso-ventrally, being
considerably more convex 'along the side facing the interior of
the conch. Vertical outlines of the septal necks are curved
slightly inward within the camerae, as in the Endoceratida. The
genus is known only in Canadian strata.

Cyrtoceras aristides Billings may be related to Eremoceras.
The siphuncle is large and in contact with the adjacent wall of
the conch, and the living chamber apparently contracts toward
the top. Better specimens than the type are needed for exact
reference.

8. CYCLOSTOMICERAS HYATT

Genotype: Gomphoceras cassinense Whitfield. Amer. Mus. Nat. Hist.

Bull., vol. 1, 1886, p. 322, pi. 29, figs. 1-3. Ruedemann, New York
State Mus. Bull., 90, 1906, p. 501, fig. 56; pi. 37, figs. 1-3; pi. 38,

figs. 5, 6

Conch subfusiform in outline, the greatest diameter being at or
immediately below mid-height of the living chamber. The

206

AUG. F. FOERSTE

lengthwise curvature of the dorsal side is greater than that of the
ventral side, and the siphuncle is close to the ventral side, but
not in contact with the latter. In this position the siphuncle is
said to be endogastric. The segments of the siphuncle present
concave vertical outlines within the camerae, as well illustrated
by Ruedemann. The septal funnels curve backward a distance
equal to one camera.

Only two species of Cyclostomiceras are known : cassinense
(Whitfield) and C. miniwMm (Whitfield) ; both are confined to
the Canadian (Beekmantown) of Vermont.

The relationship of Cyrtoceras aristides Billings, of Canadian
age, can not be determined in our present knowledge of that
species. The living chamber apparently contracts toward the
top somewhat as in a small Cyclostomiceras, but the siphuncle is
rather large. Although the siphuncle is known to be in contact
with the ventral wall of the conch, it is not possible to determine
from the type in its present condition, imbedded in the matrix,
whether its location is endogastric or exogastric. Nothing is
known about the structure of the siphuncle.

9. EXOGASTRIC CYRTOCEROIDS OF CANADIAN AGE

The conch of Cyrtoceras confertissimum Whitfield is distinctly
curved lengthwise and depressed dorso'-ventrally. The siphuncle
is near the convexly curved side of the conch. According to
Ruedemann^® the septal necks are short and the siphuncular seg-
ments are nearly tubular, but very slightly contracted within the
camerae. This concave outline of the siphuncular segments is
characteristic of the numerous species referred to Oidhoceras, by
Billings and other authors, in Canadian strata. The dorso-ven-
tral depression of the conch, however, is a feature not seen in
these so-called Orthoceroids,

In Cyrtoceras alethes Billings, which may be of Ozarkian
rather than of Canadian age, the conch is moderately curved
lengthwise and strongly compressed laterally. The ventral side
has a radius of lengthwise curvature of 25 mm. and a radius of
lateral curvature of 3 mm. Only 6 camerae are present. If the
lengthwise curvature of the ventral side continued along the liv-
ing chamber the latter would be contracted dorso-ventrally, some-
what as in the species described by Billings from the Black

^ Ruedemann, R., Cephalopoda of the Beekmantown and Chazy forma-
tions of the Champlain basin; New York State Museum Bull. 90, p. 507, 1906.

AMERICAN PALEOZOIC CEPHALOPODS

207

River of St. Joseph Island under the name Cyrtoceras huronense.
However, too little of the living chamber is present to determine
this with certainty. The siphuncle is in contact with that side
of the conch which is curved convexly lengthwise. Its segments
may be subfusiform in outline, but not enough is exposed to give
a good idea of its structure. The general resemblance of Cyrto-
ceras alethes to such forms as Cyrtoceras huronense Billings,
C. isodorus Billings, C. pandion Hall and C. plebium is sufficiently
great to make it desirable to determine with accuracy whether
such an early origin of cyrtoceroids of this type actually took
place.

The conch of Cyrtoceras metellus Billings is distinctly curved
lengthwise and the section is stated to be circular or nearly so.
The siphuncle of the type is said to be unknown. Billings stated
that this species resembled Cyrtoceras syphax Billings very
closely ; in that case its siphuncle should be located on that side
of the conch which is curved concavely lengthwise. However, in
the collections of the Geological Survey of Canada, Specimen No.
820a, labelled Cyrtoceras metellus, has the siphuncle in contact
with the convexly curved side of the conch. The segments are
strongly nummuloidal, and, owing to the concavity of the septa,
are strongly oblique to the ventral outline of the conch. More-
over, on this specimen the septa rise much higher on the con-
cavely curved side of the conch than on the convex side.

The conch of Cyrtoceras dictys Billings is distinctly curved
lengthwise and compressed laterally. The species appears related
to Specimen 820a, mentioned in the preceding lines, but nothing
is known of its siphuncle.

The siphuncle of Cyrtoceras kirhyi Whitfield is in contact with
the ventral wall of the conch, is 2 mm. in diameter, and its seg-
ments appear tubular, constricting slightly along the upper part
of the camerae, widening slightly along their lower part, and
constricting again where entering the top of the septal neck next
beneath. Cyrtoceras beekmanense Whitfield appears closely
related to kirbyi.

In Cyrtoceras raei Whitfield, the siphuncle is in contact with
the ventral wall of the conch, is 2 mm. in diameter, and its seg-
ments appear tubular. Possibly the conch was gyroceran in
form, the whorls being depressed dorsoventrally.

In Cyrtoceras vassarina Dwight, the conch is laterally com-

208

AUG. F. FOERSTE

pressed, the siphuncle is exogastric, and the vertical outlines of
its segments within the camerae are concave.

It is evident that our knowledge of the cyrtoceroids of the Ca-
nadian formations is very unsatisfactory. Of course, they would
no longer be placed under the genus Cyrtoceras, as that genus is
restricted at present. Cyrtoceras metellus Billings was referred
by Hyatt^^ to his genus Maelonoceras, but the siphuncle segments
of the latter are subfusiform, while those of Specimen No. 820a
are strongly nummuloidal.

10. ENDOCERAS HALL

First described species: Endoceras subcentrale Hall, from the Black
River (Watertown) at Watertown, New York. Pal. New York,
vol. 1, 1847, p. 57.

Accepted genotype: Endoceras proteiforme Hall. Pal. New York,
vol. 1, 1847, p. 208

Endoceras belongs to the group of genera in which the septal
necks extend posteriorly until in contact with the septum next
beneath. It is distinguished from other genera by the presence
of long endocones which taper downward gradually to a point.
The sides of these endocones are not in contact with the walls of
the siphuncle but are free along their entire length. In typical
Endoceras the endocones are few and distant from each other.
Those species in which the endocones are numerous have been
placed by Hyatt in his genus Vaginoceras.

In distinguishing Vaginoceras from Endoceras, Hyatt stated^®
that in Endoceras the septal necks extend posteriorly from one
septum only as far as the septum next beneath, while in Vagino-
ceras the septal necks extend beyond the next lower septum. It
would require a monographic study to determine to what extent
either the presence of numerous endocones or the long backward
extention of the septal necks might be regarded as of generic
value. It is still more doubtful if it is possible to distinguish a
genus (Vaginoceras) in which the septal necks are more than one
camera in length, and in which the endocones are numerous, from
another genus (Endoceras) in which the septal necks are only one
camera in length and in which the endocones are relatively few.
Apparently, if Vaginoceras is to stand, its validity must be based
upon one of these criteria alone, and not on both. The one here
selected is the presence of numerous endocones, since Endoceras
midtitahulatum Hall is the genotype of Vaginoceras.

14

Hyatt, A., op. cit., p. 280.
Idem, p. 266.

13

AMERICAN PALEOZOIC CEPHALOPODS

209

The first species described by Hall under Endoceras is sub-
centrale Hall from the Black River (Watertown) at Watertown,
New York. The type specimen of this species is numbered 603
in the American Museum of Natural History. The figure pre-
sented by Halh® shows only the middle half of the specimen and
is printed in an inverted position, with the apical end directed up-
ward. Liberties were taken in the preparation of this figure.
An endocone is present, as in the figure, but the septal necks ap-
pear to extend posteriorly for a distance of two camerae, the
lower half of each septal neck invaginating into the upper half
of that next beneath. If emphasis be placed on the lack of nu-
merous endocones, then Endoceras subcentrale is as typical an
example of Endoceras as proteiforme Hall, the genotype accepted
by Bassler.i^ If emphasis be placed on the elongation of the sep-
tal necks, then it agrees in this respect with typical Vaginoceras.
The present writer regards it as an Endoceras.

The second and third species described by Hall under Endo-
ceras, namely longissimum and multitabulatum, belong to Hy-
att’s genus Vaginoceras. The fourth species, gemelliparum, ap-
pears to be a typical Endoceras. The fifth species is the geno-
type of a new genus, Cyclendoceras, established by Grabau and
Shimer. The sixth species, proteiforme, is accepted by Bassler
as the genotype of E^idoceras, since this is the species best known,
and represented by the greatest number of specimens.

In describing Endoceras proteiforme. Hall discriminated five
varieties, namely tenuistriatum, temdtextum, lineolatum, strang-
ulatum and elongatum. Of these, tenuistriatum, tenuitextum,
and lineolatum are referred by various authors to Orthoceras.
The variety strangulatum is another Orthoceroid. Only elonga-
tum remains as a probable Endoceroid.

Typical Endoceras proteiforme Hall is represented by the fig-
ures on Plates 48, 49, 50, 53 and 57. The original of Figure 4 on
Plate 48 is selected here as the type of the species. The speci-
mens figured on Plate 49 are regarded as cotypes. Owing to the
importance of this species in the diagnosis of the genus Endo-
ceras, it is described more fully in the following lines.

Hall J., Pal. New York, vol. 1, 1847, pi. 17, fig. 4.

” Bassler, R. S., Bibliographic Index of American Ordovician and Silurian
fossils; U. S. Nat. Museum Bull. 92, p. 480, 1915.

210

AUG. F. FOERSTE

11. ENDOCERAS PROTEIFORME HALL

PLATE XXI, FIGS. 1-3; PLATE XXII, FIGS. 1-3; PLATE XXIII,
FIGS. 1-3; PLATE XXV, FIG. 2

Endoceras proteiforme Hall, Pal. New York, vol. 1, 1847, pi. 48,
fig. 4; pi. 49, 1 a-e

Selected type (Plate XXI, Fig. 1; Plate XXII, Figs. lA, IB).
The original of Figure 4 on Plate 48 of the publication cited
above is selected here as the type of the species. This specimen is
120 mm. long. It enlarges from a diameter of 45 mm. at the
lowest well defined camera to 51 mm. at a point 100 mm. farther
up, or 6 mm. in a length of 100 mm., indicating an apical angle of
3°. The cross-section is approximately circular; possibly there
is a little depression dorso-ventrally. The number of camerae
in a length equal to the diameter of the conch equals 7 along the
entire length of this specimen. The sutures of the septa are di-
rectly transverse except along the ventral side of the conch, where
they curve more or less distinctly downward on approaching the
median part. The septa curve strongly downward, their con-
cavity equaling 9 mm. where the diameter of the specimen is 48
mm. At this point the diameter of the siphuncle is 22 mm. For
a width of 10 mm. the siphuncle either is in contact with the
ventral wall of the conch or is but very slightly separated from
such contact. About 60 mm. farther up, where the diameter of
the conch is 52 mm., the diameter of the siphuncle is 30 mm.
Immediately above this part of the specimen there is evidence of
two endocones, of which the lower one is visible also at the lower
point where the diameter of the conch is 48 mm. This lower
endocone is estimated to have an apical angle of about 9°. It is
evident that the two endocones originated at septa separated by
an interval of about 7 camerae, or a length equal to the diameter
of the conch. Both endosiphocones lie on the dorsal side of the
siphuncle, but this varies in different specimens.

Other Specimens Figured by Hall. — The specimen^® repre-
sented by Figure la on Plate 49, accompanying the original de-
scription by Hall, has the ventral side of the siphuncle exposed
along a width of 18 mm. ; apparently the exposed part of the si-
phuncle originally was in contact with the ventral wall of the
conch. The septal necks are faintly concave in vertical sec-
tions. Apparently they are only a single camera in length, and

PI. 21, fig. 2; pi. 22, fig. 2; pi. 23, fig. 2, of this Journal.

AMERICAN PALEOZOIC CEPHALOPODS

211

their basal part curves outward where joining the top of the
septal neck immediately beneath. The apical end of an endo-
siphocone traverses the greater part of the length of this speci-
men ; it is almost in contact with the ventral wall of the siphuncle.
The diameter of the siphuncle is estimated at 30 mm. and that of
the conch at 58 mm., but in neither case is more than the ven-
tral side actually exposed. Five camerae occur in a length equal
to the diameter of the conch. The apical angle appears to be
larger than 3°, but the specimen is not suitable for the accurate
measurement of this angle.

The specimen^® represented by Hall’s Figures lb and Ic on Plate
43 exposes 12 camerae in a length of 106 mm. Near the base of
the specimen 7 camerae occur in a length equal to the diameter of
the conch ; near its upper end 6 camerae occur in a corresponding
length. At mid-length the diameter of the specimen is 56 mm.
Here the concavity of the septa is 15 mm. The diameter of the
siphuncle at the top of the specimen is 26 mm. If the siphuncle
was not in actual contact with the ventral wall of the conch, it
was at least very close to the latter. About 30 mm. below the top
of the specimen an endosiphocone starts downward, and 80 mm.
farther down its cross-section is seen at a distance of 1 mm. from
contact with the dorsal side of the siphuncle. Here its lateral
diameter is 15 mm., and its apical angle is approximately 7° or 8°.
The apical angle of the conch probably did not exceed 3°.

Figure Id on Plate 49 of Hall’s monograph represents a speci-
men with more numerous camerae than usual. The upper end of
an endosiphocone is exposed.

Figure le on plate 49 represents chiefly an endosiphocone^®
with an apical angle of about 8°. It is badly bent at mid-length,
and retains there part of the camerate portion of the conch,
poorly preserved.

While endosiphocones with apical angles of 9° or 10° are most
common, occasional specimens with angles distinctly lower or
higher also occur.

Locality and Formation. — Middleville, New York, in the Tren-
ton limestone.

Specimens, with one exception, all numbered 809-1. The
originals of fig. 4 on plate 48 and figs, la, lb, Ic, le on plate 49
are in the American Museum of Natural History. Fig. Id on

PL 21, fig. 3; pi. 23, fig. 1, of this Journal.

PI. 22, fig. 3; pi. 23, fig. 3; pi. 25, fig. 2, of this Journal.

212

AUG. F. FOERSTE

plate 49 represents specimen 12082-1 in the State Museum of
New York, at Albany.

12. CAMEROCERAS CONRAD

Genotype: Cameroceras trentonense Conrad. Pal. New York, vol.

1, 1847, p. 221

Cameroceras is distinguished from Endoceras chiefly by the
character of its endocones, which in Endoceras are long, grad-
ually tapering, and free from contact with the walls of the siph-
uncle, except at their extreme top, where, apparently, they are
attached to the septal necks forming the siphuncle. The general
outline of these endocones is symmetrical in every direction. In
Cameroceras the conspicuous part of the endocones is short and
rapidly tapering. Its straight part is in contact with the ventral
wall of the siphuncle, while the oblique part faces toward the
interior and is free from contact with the walls of the siphuncle.
Immediately above this conspicuous oblique conical part, the
endocone contracts more or less, sometimes only to a slight de-
gree. It is not known definitely whether the endocone extends
above this slightly contracted part for any considerable distance
or not, but apparently it continues in this direction for a length
of 6 or more camerae, in cylindrical form. The cylindrical part
appears to be a continuation of the downward extension of one
of the septal necks. It is not known whether more than one
endocone may exist in the same conch. The structure of the
endocone apparently is very similar to the ‘‘preseptal cone” of
Nanno and Suecoceras, but the conspicuous rapidly tapering part
of the endocone is beneath the camerated part of the conch in the
latter genera, while it is assumed to be surrounded by the camer-
ated part, some distance above the base of the latter, in Camer-
oceras. This location in Cameroceras is indicated, among other
things, by the annulation of the rapidly tapering part of the
endocone, especially along its free side.

Although a considerable number of endocones are at hand it
still remains to determine definitely how much of the overlying
cylindrical part of the siphuncular portion of the conch belongs
to the endocone, how the endocone is attached to the interior of
the siphuncle, and how far above the base of the conch it is
attached.

AMERICAN PALEOZOIC CEPHALOPODS

213

13. CAMEROCERAS TRENTONENSE CONRAD
PLATE XXIV, FIGS. 1-5

Cameroceras tren'tonense Conrad, Jour. Acad. Nat. Sci. Philadelphia,
vol. 8, 1842, p. 267, pi. 16, fig. 3; Hall, Pal. New York, vol. 1, 1847,
p. 221, pi. 56, figs. 4a-c

Specimens figured by — Both specimens are compressed

laterally, and in each there is a tendency toward angularity on
the dorsal or antisiphonal side of the conch. The dorso-ventral
diameter of the shorter specimen is 24 mm., and the lateral
diameter is 21 mm. Viewed from the ventral side the conch
looks slightly broader than when viewed from the dorsal side.
The rate of enlargement of the conch evidently was small. The
dorso-ventral diameter of the longer specimen is 26 mm. and
the lateral diameter is 19 mm. It is possible that this lateral
compression is due to pressure during fossilization.

The number of camerae in a length equal to the dorso-ventral
diameter of the conch is from three to three and a half. The
sutures of the septa curve slightly downward laterally, forming
shallow lateral lobes and very low dorsal and ventral saddles;
this is another feature which probably is not constant in the
species. The septa curve in a dorso-ventral direction with a
radius of 14 mm., and laterally with a radius of 8 mm., again
suggesting lateral pressure. The siphuncle is in contact with the
ventral wall of the conch for a width of 3 or 4 mm., so that this
side of the siphuncle does not show the annulations which cross
the remainder of the siphuncle obliquely.

In the longer specimen, the conch is straight ; the exposed part
of the siphuncle is likewise straight; the bend at the junction of
the siphuncle with a remainder of the conch evidently is due to
distortion during fossilization. In the shorter specimen, the
septal necks contract within the upper half of the camerae, ex-
pand within the lower half, and then contract again toward their
lower margin, so as to admit of the insertion of this margin into
the top of the next lower septal neck. The surface of the conch
apparently is smooth.

Locality and Horizon. — Middleville, New York; in the Tren-
ton limestone.

Specimens No. 815, American Museum of Natural History.

Multona Brook and Poland specimens. — Cross-section of conch

This Journal, pi. 24, figs. 1, 2.

214

AUG. F. FOERSTE

nearly circular, slightly depressed. In one specimen, (fig. 4),
the dorso-ventral diameter equals 22 mm. and the lateral diameter
23 mm., the diameter of the siphuncle being 11 mm. The num-
ber of camerae in a length equal to the diameter of the conch is
4. The sutures of the septa are directly transverse, curving
downward slightly along the median part of the ventral side and
sometimes also laterally. As far as known, the septal necks
extend downward the length of one camera, and invaginate into
the top of the septal neck next beneath.

In the second of the specimens from Multona brook (PI. 24,
Fig. 3), the siphuncle is in contact with the ventral wall of the
conch, and is fiattened and not annulated along this line of con-
tact. Around the remainder of its circumference the siphuncle
is strongly annulated, in an oblique direction, the annulations
forming an angle of 70° with the vertical axis of the conch.
Toward the tip of the endocone the angle made by the annula-
tions appears to become a little more acute.

The interior of the rapidly contracting part of the endocone
and the adjacent part of the cylindrical siphuncle, immediately
above, is lined by a calcareous deposit. In the Poland specimen
(PI. 24, Fig. 5), this calcareous deposit fills the lower part of the
endocone for a distance of 7 mm. from its tip. Immediately above
this level the thickness of the calcareous deposit equals 2 mm.
At the upper end of the inversely conical part of the endocone,
the thickness of the calcareous deposit is 1 to 1.5 mm. Four
camerae farther up, within the cylindrical part of the endocone,
the thickness of the calcareous deposit is reduced to half a
millimeter.

Two of the specimens from Multona brook preserve casts of
the interior of the endocone; one of these is figured here (PI. 24,
Fig. 3). It has proved impossible so far to determine with con-
fidence how much of the conch is to be included in the structure
here called the endocone. The conspicuous part of the endocone,
which tapers rapidly downward, varies from 4 to 6 camerae in
length in different specimens, but it is not known how much of the
overlying cylindrical part is to be included in the endocone. In
other words, it has been impossible, so far, to distinguish be-
tween the walls of the siphuncle and the walls of the endocone, or
to determine at what level the top of the cylindrical portion of
the endocone originates. Possibly all of the cylindrical portion

AMERICAN PALEOZOIC CEPHALOPODS

215

belongs to the siphuncle, and no part of this cylindrical portion
to the endocone.

Locality Md Horizon. — Multona brook, 2 miles northeast of
Middleville, New York; specimens No. 59449, U. S. National
Museum. One mile above Poland, in Herkimer county. New
York; specimen 59450, U. S. National Museum. Both localities
in the Trenton limestone.

14. CAMEROCERAS CALUMETTENSE SP. NOV.

PLATE XXIV FIGS. 6A-E

Specimen 05 mm. in length, consisting of part of a siphuncle
traversing nine camerae in a length of 52 mm. and terminating
at the base in an endocone three camerae in length. Possibly the
siphuncle is one camera less and the endocone one camera more
in length, since in two other specimens the endocone is four
camerae in length.

In the longer specimen here figured (PI. XXIV, Figs. 6 A, B),
the siphuncle narrows from a width of 12 mm. immediately
above the point of departure of the endocone to 10.5 mm., 8
camerae farther up. A second specimen shows the same nar-
rowing of the siphuncle in an upward direction.

Not only the siphuncle, but also the endocone, is flattened ven-
trally by contact with the ventral wall of the conch. This is
indicated by 3 specimens. (Plate XXIV, Figs. 6 A, C). Except
along this flattened ventral part, both the siphuncle and the endo-
cone are annulated toward the interior of the conch. The lower
margin of the septal funnels, as seen on casts of the interior of
the siphuncle, forms an angle of 60° to 70° with the vertical axis.
Along the greater part of its length, the annulations of the siph-
uncle are parallel to the lines of contact with the septa, but, on
approaching the upper margin of the endocone from above, the
angle made by the annulations changes to 75° or 80° with the
vertical, thus shortening the distances between the annulations
on the dorsal side of the siphuncle.

On the ventro-lateral sides of the siphuncle, vertical sections
of the septa can be traced for 6 mm. from the siphuncle. Ven-
trally, the siphuncle was in direct contact with the wall of the
conch.

The siphuncle appears to consist of a darker exterior layer
and a lighter colored interior one. The darker layer evidently
is a continuation of the septum and can be traced downward the

216

AUG. F. FOERSTE

length of one camera where its margin invaginates into the upper
part of the septal neck next beneath. The lower margin of each
septal neck extends about 1 mm. below the top of the underlying
one. The light colored layer appears to be merely a calcareous
inner lining of the darker colored one and, as far as known,
also extends downward only the length of a single camera.

The interior of both the siphuncle and of the endocone (Plate
XXIV, Figs. 6D, E), is lined by a calcareous deposit, which
attains a thickness of about 4 mm. at the top of the endocone,
diminishing to 2 mm. about 3 camerae farther up, and to about
three-quarters of a millimeter 8 camerae above the top of the
endocone. About half way dovv^n the length of the endocone the
calcareous deposit completely fills its interior. The matrix filling
the upper half of the axial part of the endocone and the over-
lying part of the siphuncle is obliquely annulated in a manner
strictly corresponding to the annulations on the exterior of the
siphuncle, but the annulations are less prominent. Passing
along the axial part of the solid deposit filling the lower half of
the endocone is a thin band, a millimeter or less in width, but
only about one-fifth of a millimeter thick dorso-ventrally, which
evidently was originally an endosiphuncle, filled in successively
from above by curved transverse, thin layers whose concave sides
face upward.

Locality and formation. — From the cephalopod bed at the base
of the Maquoketa on Little Calumet creek, 6 miles south of
Louisiana, Missouri. Collected by. Ulrich and Kirk in 1911,
and now in the U. S. National Museum.

15. ASCOCERAS BARRANDE

Genotype: Ascoceras bohemicum Barrande. Barrande, Syst. Sil. du
Centre Boheme, pi. 93

The Silurian genera Ascoceras, Glossoceras, and Aphragmites
have laterally compressed gerontic living chambers, differing in
this respect from the Ordovician genus Billingsites in which these
chambers are depressed dorso-ventrally. In the three Silurian
genera the upper part of the living chamber is contracted into a
tubular portion which terminates in Ascoceras and Aphragmites
in a simple transverse aperture, but which in Glossoceras has
distinct dorsal and lateral crests, with intermediate sinuses.
The general transverse section of the upper tubular portion may
be circular or moderately depressed dorso-ventrally. In Ascoceras

AMERICAN PALEOZOIC CEPHALOPODS

217

and Glossoceras the exterior of the shell is smooth. In Aphrag-
mites the exterior of the living chamber is sharply annulated
transversely.

In American strata the genus Ascoceras is represented by the
species Ascoceras indianense Newell from the Niagaran at
Delphi, Indiana, Ascoceras southwelli Worthen from the Niaga-
ran at Port Byron, Illinois, and Ascoceras townsendi Whiteaves
from the Niagaran (Guelph) at Durham, Ontario. In the last
named species the gerontic group of living chambers appears to
have been relatively much shorter than in typical forms of
Ascoceras.

16. BILLINGSITES HYATT

Genotype: Ascoceras canadense Billings. Rep. Progress for 1853-56,
1857, Geol. Surv. Canada, p. 310; Geol. Canada, 1863, p. 318, fig. 227

Billingsites differs from typical Ascoceras chiefly in having
the gerontic group of living chambers dorso-ventrally depressed,
instead of laterally compressed as in the latter genus. The con-
tracted part of the living chamber, above the level of the upper-
most dorsal saddle, is much shorter in Billingsites and is more
distinctly depressed dorso-ventrally. The margin of the aper-
ture is transverse, without crests or sinuses. The genus is
known so far only from the Ordovician.

The genus Billingsites includes Billingsites articostiensis (Bil-
lings) from the Gamachian (Ellis Bay) of Gamache Bay, Anti-
costi; Billingsites borealis (Parks) from the Richmond (Sham-
mattawa) of Shammattawa river, Manitoba; Billingsites costu-
latus (Whiteaves) from the Richmond of the Lake Winnipeg
region in Canada; and Billingsites newberryi (Billings) from
the Richmond (English Head and Vaurial) and Gamachian of
English Head and other localities on Anticosti. The genotype is
Billingsites canadensis (Billings) from the English Head and
Vaurial of Anticosti.

The specimen described by Sardeson under the name Ascoceras
gibberosum, from the Ozarkian (Oneota) of Dresbach, Minne-
sota, according to Dr. E. 0. Ulrich belongs to a new genus of
Chiton, related to Priscochiton, now under investigation.

17. BILLINGSITES (?) WILLIAMSPORTENSIS SP. NOV.

PLATE XXXV, FIGS. 2A, B, C

The specimen has the external form of the gerontic living
chamber of a Billingsites. It is depressed dorsoventrally, and
the more convex side is regarded as ventral, the less convex as

218

AUG. F. FOERSTE

dorsal. A vertical dorsoventral section through the center of
the specimen exposes two septa, of which the lower is more dis-
tinct. This septum rises from a level of 6 mm. above the base
of the specimen on its ventral side to 17 mm. at a point 4.5 mm.
distant from its dorsal wall. The upper septum is 4 mm. above
the first on its ventral side and rises to 25 mm. above the base of
the specimen at a point 1.5 mm. from its dorsal wall. The dorsal
terminations of these septa are unknown ; no trace of the
siphuncle remains.

The lateral view reproduced as figure 2A, Plate XXXV, shows
the ventral side on the left. Figure 2B on the same plate presents
the ventral side, and figure 2C the dorsal.

Locality : From the Catheys formation at Williamsport, Tenn-
essee. Specimen 48395 in the U. S. National Museum.

Remarks : This species may be a precursor of typical Billing-
sites, the rise of the septa on its dorsal side forshadowing the
formation of the strongly developed dorsal saddles of that genus.

18. ORTHOCERAS BREYNIUS

The name Orthoceras or Ortho ceratites was applied first by
Breynius““ to erratic specimens found in the vicinity of Danzig
in Germany. From this location it may be assumed that the
erratic blocks containing these specimens were either of Ordovi-
cian or Silurian origin. There is a possibility that some one
visiting the original locality might be able to identify the species
figured. Nothing is known as to the fate of the original speci-
mens.

The figures published by Breynius show that the rate of en-
largement of the species described by him was very small. The
septa were relatively distant, about 2 camerae occurring in a
length equal to the diameter of the conch. The siphuncle was
small, omewhere between one-sixth and one-seventh of the
diameter of the conch. Its segments were cylindrical, not en-
larging within the camerae. The septa were deeply concave.

The nearest approach to Orthoceras, as figured by Breynius,
with which the writer is familiar, is a species of Lituites, from
Esthonia, well represented in the collection of the U. S. National
Museum (Plate XXVIII, Fig. 3). In these specimens the an-
nulations on the exterior of the shell are accompanied by very
weak annulations on casts of the interior. The camerae of this

“ Dissert. Phys. de Polythalmiis, 1732, pp. 12, 19, 31; PI. Ill, Figs. 1-7.

AMERICAN PALEOZOIC CEPHALOPODS

219

species are relatively long, and the siphuncle is only moderately
excentric.

It is evident that the type of Orthoceras, if this genus is to be
accredited to Breynius, must be some species which could have
been carried southward by glacial action to the vicinity of Dan-
zig. If any true Orthoceroid is known which could have been
the species figured by Breynius, it is desirable that attention be
called to this fact.

In this connection it might be of interest to note that the
genus Lituites was defined by Breynius in the same work in which
he defined Orthoceras. In neither case was a binomial nomencla-
ture used, and it is doubtful whether either genus, under these
circumstances, should be ascribed to Breynius.

The species figured by Breynius is cited by Schlotheim in his
description of Orthoceras regulare, evidently in the belief that
the two were identical.

However, it is evident from his citations of figures of ortho-
ceracones published by Bose, Knorr, and Breynius, that he in-
cluded several species under this name, and that the species
figured by Breynius can not be considered the type of regulare.

Hyatt restricted the term Orthoceras to forms with smooth
shell, and stated"'^ that he had met but two species in North
America, though doubtless others may exist. In the Zittel-
Eastman Text-book of Paleontology he figured two species under
Orthoceras, namely intermedium Marklin from the Silurian of
Gotland, and michelini Barrande from the Silurian of Bohemia.
Of these two species, the first differs from typical Orthoceras in
the greater number of its camerae (about 8 in a length equal to
the diameter of the conch), and in the distinct, though slight,
enlargement of the siphuncle within the camerae. The second
species, however, is closely similar to typical Orthoceras in the
elongation of its camerae and in the tubular form of the segments
of its siphuncle. Until the exact status of the species figured by
Breynius can be determined, Orthoceras michelini Barrande may
be accepted as the type of Orthoceras as restricted by Hyatt.

Typical Orthoceras occurs chiefly in the Silurian, but similar
specimens apparently occur also in the Richmond formation, in
the upper part of the Ordovician. A description of the species
occurring in the Richmond at Clarksville, Ohio, follows :

** Hyatt, A., Genera of fossil cephalopods; Proc. Boston Soc. Nat. Hist.,
vol. 22, p. 275, 1883.

220

AUG. F. FOERSTE

19. ORTHOCERAS CLARKSVILLENSE SP. NOV.

PLATE XLII

Specimen 130 mm. in length, consisting of 16 camerae, of
which the uppermost is distinctly shorter, suggesting that the
conch had reached full maturity. The specimen apparently en-
larges from a diameter of 21 mm. at its base to 28 mm. at its top,
indicating an apical angle of about 4°. Near the. base of the
specimen two and a half camerae occur in a length equal to the
diameter of the conch. Toward the upper part, three camerae
occur in a corresponding distance. The sutures are directly
transverse. The septa have a concavity of 5 or 6 mm. at mid-
length of the specimen. The center of the siphuncle is located
about one-third of the diameter of the conch from its central side.
The segments of the siphuncle are cylindrical in form and their
diameter is about 3 mm. along the entire length of the specimen.
No part of the exterior shell remains, but the cast of the interior
of the conch is smooth and it is possible that the exterior of the
shell was smooth also.

Locality and Horizon. — Clarksville, Ohio ; either from the Lib-
erty or the Waynesville member of the Richmond.

Specimen No. 48255, in the U. S. National Museum.

Similar specimens have been collected by Prof. W. H. Shideler
in the basal part of the Liberty at Clarksville, Ohio; and in the
lower Whitewiater, on Dodge creek, near Oxford, Ohio.

A similar specimen, but with somewhat more distant septae,
was found in the Richmond about a mile north of the light house
at the southern end of Bay de Noc peninsula, in Northern Michi-
gan, in strata probably equivalent to the Whitewater member.-^
Additional specimens have been found in the Stonington area,
farther northward on the same peninsula, by Dr. R. C. Hussey,
of the University of Michigan.

Remarks. — It has not been determined to what extent the
form of the segments of the siphuncle in Orthoceroids is depend-
ent on the relative distance between the septa. In general it may
be stated that in those forms in which the septa are more dis-
tant from each other the segments of the siphuncle tend to ex-
pand less within the camerae, sometimes being cylindrical, while

Foerste, A., The Richmond faunas of Little Bay de Noquette in northern
Michigan; Ottawa Nat., vol. 31, p. 122, pi. 5, fig. 19, 1917.

AMERICAN PALEOZOIC CEPHALOPODS

221

in forms in which the septa are relatively close together these
segments tend to be globular or nummuloidal.

Cylindrical segments are frequent in such genera as Dawson-
oceras, Kionoceras, and Protokionoceras ; they occur also in some
species of Spyroceras and Cycloceras. Evidently, the cylindrical
formx of the segments of the siphuncle is not sufficient, in itself,
to determine the generic relationship of an Orthoceroid cephalo-
pod. According to the Hyatt classification, the character of the
surface ornamentation also must be taken into account.

20. GEISONOCERAS HYATT

Genotype: Orthoceras rivale Barrande; Syst. Sil. du Centre Boheme,

pi. 209

The genus Geisonoceras was erected by Hyatt for the banded
Orthoceroids of Barrande. A banded form differs from a trans-
versely striated one in having the striae more distant, the upper
margin of the band being abruptly defined, while the general
surface of the band contracts gently and evenly in an apicad
direction. Successive bands overlap each other in an oral direc-
tion. The genus probably was evolved frcm forms having rela-
tively closer transverse striae. According to Hyatt, the young
are either smooth or transversely striated.

Hyatt selected as the type of this genus Orthoceras rivale Bar-
rande, from the Silurian of Bohemia. In this species two and a
half camerae occur in a length equal to the diameter of the conch.
The siphuncle is slightly excentric, and it enlarges slightly within
the camerae. In the Zittel-Eastman Text-book of Paleontology
he figures as Geisonoceras the Orthoceras timidiim Barrande of
the Silurian of Bohemia, and defines the genus without referring
to its characteristic transverse banding. The genus Geisono-
ceras, however, must be regarded as founded upon Orthoceras
rivale, the original type, and not on Orthoceras timidum.

In the Zittel-Eastman textbook, Hyatt defines Orthoceras as
having a siphuncle centren or slightly dorsad of the center. The
siphuncle of Geisonoceras is stated to be centren or slightly ven-
trad of the center. As applied to Orthoceroids, the terms dorsad
and ventrad need some explanation. In those specimens in which
the conch is distinctly though slightly curved lengthwise, the
convex side usually is regarded as the ventral one. Theoretically,
the ventral side should be located by the presence of an hypo-

222

AUG. F. FOERSTE

nomic sinus. However, since Orthoceroids do not have an hypo-
nomic sinus, this method of orienting the conch can not be used
for them. When the transverse striae slope distinctly downward
from one side of the conch to the other, the lower part of their
course is supposed to correspond to the hyponomic sinus, at least
in those forms which are not curved lengthwise. It may be
acknowledged freely that in the present state of our knowledge
of the Orthoceroids the terms dorsal and ventral are used loosely.
In the absence of all other criteria, that side of the conch which
is nearest the siphuncle is called the ventral one, lat least pro-
visionally.

Banding is by no means confined to the genus Geisonoceras, It
occurs also in breviconic forms, as indicated by Hyatt,^° and in
some species of Actinoceroids.

21. CYCLOCERAS McCOY

The genus Cycloceras was defined by McCoy^® as consisting of
“those conical species marked with prominent concentric rings,
and having the surface frequently sculptured with transverse
scaly laminae, and often decussated; siphuncle dorsal.’^ This
description is accompanied by a small figure with vertical striae
or ribs, but the figure does not resemble any species described
or listed by him in the text. Among the species known at that
time, it most resembles Orthoceras rugosum Fleming, as repre-
sented by Phillips,^^ and that species is therefore regarded here
as the genotype. In this figure the annulations are tuberculated
by longitudinal echinated lines, of which there are apparently
about 18 on the entire circumference of the conch. The expres-
sion, “siphuncle dorsal,’’ at present would be changed to siphuncle
ventral.

None of the species described or listed by McCoy in the body
of his text agrees with his description of the genus in the posses-
sion of vertical lines of any kind. The first species mentioned
was originally described by Fleming-® as Orthocera annularis,
Fleming’s illustration is reproduced herewith as figure 4, plate
XXV. The surface of this species is said to be smooth, except

Hyatt, A., op. cit., p. 275.

Syn. Garb. Foss. Ireland, 1844, p. 6, fig. 6.

Geology of Yorkshire, 1836, pL 21, fig. 16. See also Fleming, Ann. Phil,
vol. 5, 1815, p. 203, pi. XXXI, fig. 9.

^ Ann. Phil., vol. 5, 1815, p. 203, pi. 31, fig. 8.

AMERICAN PALEOZOIC CEPHALOPODS

223

for the annulations. A larger form was given the same name
by Phillips-® and his illustration is here reproduced as figure 5,
plate XXV. Lts surface had annular ridges and intervening
waved striae. The second species described by McCoy is Cyclo-
ceras laevigatum McCoy, represented by him as figure 3 on his
plate 1. At the time of the original description no transverse
striae were known. Probably the type was a cast of the interior
of the conch, on which the surface striae leave no impress.
Later Foord^® figured specimens of the same species in which
transverse striae are present where the shell is preserved. His
illustrations are reproduced herewith as figures 3A and 3B on
plate XXVII. Possibly the surface of the shell of Orthocera
annularis Fleming was similarly striated.

The third species described by McCoy under Cycloceras was
the form described by Phillips'^S in the body of his text,, as
Orthoceras annulatum, but which in his description of plates he
referred to Orthoceras annulare. This form possesses trans-
verse striae in addition to the annulations, but there are no
vertical striae or ribs. It is the only one of the three forms
listed by McCoy in which transverse striae were known to be
present at the time of the description of his genus Cycloceras.
McCoy identifies this species with Orthoceras Uneolatum Phillips
and cites the description based on the specimen represented in
this Journal on pi. XXV, (fig. 5).

It appears, therefore, that McCoy included in his genus Cyclo-
ceras at least two distinct types of structure. In one, the annula-
tions were tuberculated where crossed by longitudinal lines; in
the other only transverse striae were present in addition to the
annulations. The first type of structure is that indicated by his
original description and the accompanying small figure. The
second type of structure is that of the three species mentioned by
McCoy in the body of his text.

Hyatt^^ in 1883 defined Cycloceras as including transversely
striated Palaeozoic longicones, which at some stage of their
growth have annular costae. Subsequently in the Zittel-Eastman
Text-book of Paleontology, he re-defined the genus as including
annulated orthoceracones and cyrtoceracones with discontinuous

Geology of Yorkshire, 1836, pi. 21, fig. 9.

Garb. Ceph. Ireland, 1897, pi. 5, fig. 1.

op. cit., p. 239, pi. 21, figs. 9, 10.

Hyatt, A., op. cit., p. 275.

224

AUG. F. FOERSTE

longitudinal ridges. The first of these definitions evidently is
based on the species cited in McCoy’s text. The second definition
is based on the original description of the genus and the small ac-
companying figure. Accepting the latter as the more correct in-
terpretation of the genus, the forms possessing only transverse
striae and no longitudinal markings, have no distinct generic
designation, and the term Perigrammoceras here is proposed.

Bassler lists under Cycloceras a number of species having ver-
tical striae or ribs in addition to annulations. These include Or-
thocey^as crocus Billings, 0. ohms Hall, 0. olorus haffinense
Schuchert, 0. perroti Clarke, and 0. teretiforme Hall. It is not
knov^n definitely whether Orthoceras leseuri Clarke, O. nicoUeti
Clarke, and 0. rectiannulatum Hall belong to the same group as
the preceding list, since the finer surface structure of these
species is not known, only the presence of annulations being cer-
tain. It is probable that these Ordovicion forms are distinct gen-
erically from typical Cycloceras, as found in Carboniferous
strata. Provisionally they are associated with Spyroceras.

Orthoceras inceptum Foerste and its variety acceleratum
Foerste apparently belong to Orthoceras, as far as known.

Orthoceras (Cycloceras) novacarlislense Foerste has sharply
defined transverse striae, but no annulations. Evidently it does
not belong to Cycloceras. Its nearest relationship probably is
with Geisonoceras.

The transverse striae of Orthoceras amycus Hall, are gently
frilled, and the species belong to Dawsonoceras.

22. PERIGRAMMOCERAS GEN. NOV.

PLATE XXVII, FIGS. 3 A, B.

Genotype: Orthoceras laevigatum, as figured by Foord, in Carb. Ceph.

Ireland, 1897, pi. 5, figs. Id, le

Orthoceracones with transverse annulations and striae, but
without vertical striae or ribs. Carboniferous.

It is not known definitely whether this genus is represented in
earlier strata or not. In annulated forms with transverse striae
occurring in the Ordovician and Silurian it usually is possible to
detect also vertical striae or ribs, if the surface is sufficiently well
preserved.

AMERICAN PALEOZOIC CEPHALOPODS

225

23. DAWSONOCERAS HYATT
Genotype: Orthoceras annulatum of McGill college, Montreal

Dawsonoceras is another instance of a genus erected by Hyatt
chiefly with Biarande species in mind, but with an American
species designated as the type. In his original description he
states that the genus includes forms like Orthoceras pseudoca-
lamiteum Barrande, but at the close of his description he desig-
nates Orthoceras annulatum, from the Museum at McGill College,
as the type. The latter belongs to the species characterized by
transverse annulations and transverse frilled striae. Longi-
tudinal ridges, considerably less conspicuous than the transverse
annulations, may or may not be present.

In the Zittel-Eastman Text-book of Paleontology Hyatt figures
under Dawsonoceras the Orthoceras annulatum of Bohemia, af-
ter Barrande, and not the specimen in the Museum of McGill
College. It is evident, from the presence of frilled transveise
striae, that Orthoceras amycus Hall belongs in the genus Daiv-
sonoceras.

In Perigrammoceras the transverse striae are straight and not
frilled.

24. SPYROCERAS HYATT

Genotype: Orthoceras crotalum Hall. Pal. New York, vol. 5,
pt. 2, 1879, pis. 42, 82, 113

In defining this genus Hyatt apparently had in mind chiefly
groups 5 and 6 of the species of Orthoceras described by Bar-
rande, but, when it came to selecting the genotype, he chose Or-
thoceras crotalum Hall from the Hamilton formation of New
York.

The conch of Orthoceras crotalum is crossed transversely by
strong, sharply defined, and rather distant annulations. The
vertical striae are very fine and closely crowded. A similar
species, with closely crowded vertical striae, but with wider and
less sharply elevated annulations, is found in the Richmond of
Anticosti.

In general, however, the earlier species of Spyroceras, in the
Ordovician, have stronger and less crowded vertical markings,
often designated as ribs, or as ribs alternating with vertical
striae. These may form a group distinct from the finely striated
forms.

226

AUG. F. FOERSTE

25. LOXOCERAS McCOY
PLATE XXVIII, FIGS. 2A, B
Selected genotype: Loxoceras distans McCoy

The genus Loxoceras was defined by McCoy as consisting of
orthoceracones “in which the section is oval, the septa waved and
placed obliquely with respect to the axis of the shell, and the si-
phuncle is excentric.'' This description is accompanied by a
figure,®'^ in which the sinuosity of the sutures of the septa agrees
with that of Loxoceras distans McCoy, though the septa are
drawn closer together. A study of the figures presented by Mc-
Coy in connection with his generic descriptions, in the volume
cited, suggests that these figures were intended to be diagram-
matic, and not accurate representations of type specimens.
Moreover, he certainly never intended the first species described
in the text under this generic name to be accepted as the type.
Had he done so, he would not have published Orthoceras hreynii
Martin (Plate XXV, Fig. 3) first, but would have selected the
one he published second, namely Loxoceras distans McCoy, which
differs from the figure accompanying the original description of
the genus chiefly in having more distant septa. The sutures of
Orthoceras hreynii present undulations, but of moderate obliquity
compared with typical Loxoceras, and the siphuncle is located
near the middle of that broad side of the conch along which the
sutures curve moderately downward.

In Loxoceras distans, on the contrary, the sutures of the septa
are strongly oblique in a sigmoid direction, and the location of
the siphuncle is central. The word Loxoceras means oblique
horn, and evidently refers to the strongly oblique sutures.

The siphuncle of Orthoceras hreynii Martin is described by
McCoy as follows :

“Siphuncle small, and a little within the margin, where it
passes through the septa, but dilated between them into de-
pressed spheroidal beads, about twice as wide as long, and touch-
ing the surface throughout the length of the shell; interior of
the siphon traversed by a small continuous tube, attached to the
inner walls of the dilated portion by radiating, vertical, shelly
partitions (about eight in a whorl) ,• constricted by transverse
stronger partitions in the middle of each dilation (or intermediate
between the septa) . Surface, (of the shell) indistinct, apparently
marked with fine, obtuse, transverse striae. The proportion of

“ McCoy, Syn. Carb. Foss. Ireland, 1844, p. 6, fig. 3.

AMERICAN PALEOZOIC CEPHALOPODS

227

the long and short diameter of the section is as 100 to 85. A
specimen five inches long is one inch three lines Avide at the large
end, and two lines wide at the apex, the dilated part of the siphon
at the latter point equalling the whole diameter of the shell, but
being only 5 lines wide at the anterior (upper) end, where two
chambers occupy a space of slightly less than half an inch, while
six chambers occupy the same space at the smaller end. The
internal structure is that of Actinoceras Stokes, though it is
marginal in position, and the septa are more oblique.’'

McCoy evidently had not a very clear idea as to the limits of his
genus Uoxoceras. This is shown by the fact that the species de-
scribed third under Loxoceras, namely Loxoceras incomitatum
McCoy, does not have the strongly oblique sutures. His fourth
species was Orthoceras laterale Philips. The longitudinal view
presented in Figure 3 accompanying the original description of
the genus is regarded here as a diagrammatic representation of
his species Loxoceras distans, while the small cross-section is in-
tended to show the course of the sutures in Orthoceras breynii,
the siphuncle of the latter being located along the middle of that
broad side along the median line of which the sutures curve mod-
erately downward.

26. SACTOCERAS HYATT

Genotype: Orthoceras richteri Barrande. Syst. Sil. du Centre Boheme,

pis. 318, 349

Orthoceracones with relatively small siphuncles, the segments
of the latter nearly spherical or slightly elongated. Septal necks
short, enveloped on the interior of the siphuncle by lunate cal-
careous deposits, which enlarge as in other Actinoceroids. Su-
tures of the septa directly transverse. Described from the Si-
lurian.

It is doubtful whether the Carboniferous species Loxoceras
distans is to be regarded as congeneric with Sactoceras. Using
the former as the type of Loxoceras, there appears to be use for
Sactoceras as the designation of a distinct group, certainly pres-
ent in the Silurian, and apparently beginning with forms in the
Ordovician in which calcareous deposits of an Actinoceroid na-
ture are unknown.

228

AUG. F. FOERSTE

27. ELRODOCERAS GEN. NOV.

Genotype: Crytoceras indianense Miller

Conch Actinoceroid, cyrtoceraconic , at the base, relatively
straight at later stages of growth. Siphuncle ventrad of the cen-
ter of the conch. Segments of the siphuncle presenting moder-
ately convex vertical outlines; general form barrel-shaped, the
end flat, and in contact with the intervening part of the septa.
Surface of the conch transversely striated or banded as in the
banded orthoceracones included by Hyatt under Geisonoceras.
The bands curve downward along the ventral side of the conch,
indicating a shallow but distinct hyponomic sinus.

Rhynchorthoceras Remele belongs to the Lituitidae, a family
confined to the Ordovician.

The name Elrodoceras is proposed in honor of Dr. Moses N.
Elrod, an indefatigable collector long living at Hartsville,
Indiana.

28. ELRODOCERAS INDIANENSE (MILLER)

PLATE XXXV, FIGS. lA, B; PLATE XXXVI, FIGS. lA, B; PLATE
XXXVII, FIGS. 2, 3; PLATE XXXVIII, PIGS. 2, 3
Crytoceras indianense Miller; 17th Ann. Rep. Dep. Geol. Nat. Res.

Indiana, 1892 p. 698, pi. 18, figs. 1, 2
Rhynchorthoceras dubium Hyatt; Proc. Amer. Phil. Soc., vol. 32,

1894, p. 512

St. Paul type. — Early stages cyrtoceraconic, later stages rela-
tively straight. The lengthwise convex curvature along the
lower end of the ventral side has a radius of about 40 mm., the
corresponding concave curvature of the dorsal side being much
less. The specimen includes 15 camerae, in addition to which a
trace of a segment of the siphuncle is. seen at its base. Along
the upper 9 or 10 camerae the ventral side of the conch is straight
lengthwise. The sutures of the septa are directly transverse to
the conch. The . siphuncle is well exposed within the upper 4
camerae. Within the uppermost camera, its maximum diameter
is 23 mm., narrowing to 19 mm. at the septa. The septa wedge
in between the successive barrel-shaped segments, the central
passage through the septa being 12 mm. in diameter. At the
septa, the siphuncle is 12 mm. distant from the ventral wall of
the conch, and about 23 mm. from its dorsal wall, the entire
diameter being estimated at 54 mm.

The uppermost segment of the siphuncle exposes a cast of its
interior ; the latter is marked vertically, both above and below an
irregular transverse line which crosses the cast not far above

AMERICAN PALEOZOIC CEPHALOPODS

229

mid-height. This transverse line indicates where the calcareous
deposits enveloping the successive septal necks of the siphuncle
meet, as in other Actinoceroids. At the top of the specimen, the
interior of the siphuncle shows an irregular central depression,
probably corresponding to the so-called endosiphuncle of Acti-
noceroids.

The interior of the camerae is occupied by a calcareous de-
posit, showing a few cystoid markings, and also a tendency to-
ward pseudo-septa.

The exterior surface of the shell is striated transversely by
narrow bands, abruptly limited along their upper margins, but
more gradually sloping toward their lower margins. About 14
to 16 transverse striae occur within a length of 10 mm. On the
dorsal and lateral sides of the conch these striae are directly
transverse, but along the ventral side they curve gently down-
ward.

Locality and Horizon. — St. Paul, Indiana, in the Laurel lime-
stone (Silurian).

Specimen No. 633, in the Indiana State Museum, at Indian-
apolis, Indiana.

Hartsville type. — The second specimen figured by Miller, in
his original description of Cyrtoceras indianense, consists of 11
camerae. The lengthwise convex curvature of the ventral side
along the 3 lower camerae has a radius of 45 mm. ; the fourth
camera is distinctly less curved, and the ventral side of the up-
per part of the conch is straight. In a corresponding manner, the
dorsal side of the specimen is concavely curved along the 3 or 4
lower camerae, and becomes straight farther up. The dorso-
ventral diameter enlarges from 29 mm., at the top of the third
camera from the base, to 36 mm. at the top of the seventh camera,
the intervening distance being 45 mm. This suggests an apical
angle of 9° along the straight part of the specimen. The speci-
men is curved laterally, especially along the lower part.

There are three camerae in a length equal to the dorso-ventral
diameter of the conch at mid-length of the specimen. The upper
four segments of the siphuncle are exposed. Their height is 11
mm. They are represented by deposits lining the interior of
their walls. From these deposits it is evident that the diameter of
the segments enlarges scarcely 2 mm. on passing from their con-
tact with the septa to their greatest diameter at mid-height.
Where the dorso-ventral diameter of the conch is 36 mm., the

230

AUG. F. FOERSTE

maximum diameter of the segments of the siphuncle is 13 mm.
At its passage through the center of the septum the siphuncle is
constricted abruptly to a diameter of 5 or 6 mm. The outer sur-
face of the deposit which lines the inner side of the walls of the
segments of the siphuncle is corrugated vertically. A short dis-
tance above mid-height of the segments, these corrugations are
interrupted by a horizontal groove. This groove marks the line
at which deposits embracing successive septal necks meet.

The thickness of the shell is somewhere between one-half and
three-quarters of a millimeter. Its outer surface is striated or
banded transversely. Along the lateral sides of the conch these
striae are directly transverse, but along its ventral side they
curve downward moderately, locating the hyponomic sinus.

Locality and Horizon. — From Hartsville, Indiana, at the top
of the Laurel limestone, immediately beneath the Waldron shale.

Specimen No. 6056, In the Walker "^Museum at Chicago Uni-
versity.

Rhynchorthoceras duhium. — The type of Rhynchorthoceras
duhium is curved at its base, but straight farther up. One of the
lateral sides retains the surface striae, curving downward ven-
trally. The opposite lateral side exposes the sutures of the septa.
The conch is slightly compressed laterally, and the siphuncle is lo-
cated ventrad of the center of the conch. A second specimen, not
described by Hyatt, shows very well the downward curvature of
the transverse striae along the ventral side of the conch. The op-
posite side exposes the sutures of the septa, which are directly
transverse. The siphuncle is seen at the top of the specimen.
(Plate XXXV, Figs. lA, B.)

Locality and Horizon. — Hyatt referred to his type as occur-
ring in the Niagara group of Indiana. The exact locality is un-
known, but it probably came from the upper part of the Laurel
limestone in the St. Paul or Hartsville area. This type is num-
bered 2132 in the Museum of Comparative Zoology at Harvard
University. The second specimen is numbered 2133.

Joliet specimen. — One specimen includes, at its base, part of
the lengthwise curved portion. The transverse striae curve dis-
tinctly downward on the ventral side of the conch. There is a
tendency toward obscure transverse costae, which slope obliquely
downward from the dorsal toward the ventral side of the conch
at a rate much more rapid than that of the transverse striae.

AMERICAN PALEOZOIC CEPHALOPODS

231

One of the segments of the siphuncle, at the base of the specimen,
exposes the deposit lining the interior of the siphuncle, and the
abrupt constriction of the siphuncle where it passes through the
septum. Specimen No. 22920, in Walker Museum at Chicago
University. A fragment of a siphuncle, showing the abrupt con-
striction of the siphuncle, is referred to the same species. It
(Plate XXXVIII, Fig. 3) is numbered 22916 in the same museum.
Both are from the Niagaran.

Lemon t specimen. — A specimen (Plate XXXVII, Fig. 3) ex-
posing the structure of the interior of the conch, from the Niag-
aran at Lemont, Illinois, is numbered 22917 in Walker Museum.

29. TRIPTEROCERAS HYATT

Genotype: Orthoceras hastatum Billings. Geol. Surv. Canada, Rep.

Progress for 1853-56, published in 1857, p. 333

Original Description: Tripteroceras has similar forms and
sutures to Eudoceras, but the lateral saddles are acute. The ven-
ter is flattened, and broader than the dorsum, which forms the
apex of the subtriangular section. The siphon is ventral and
nummuloidal, and the whorl arcuate in the young, though straight
in the full grown, and the aspect altogether distinct from the
shells of Eudoceras. The young are similar to the adults of
Eiidoceras.^"^

The genotype is Orthoceras hastatum Billings. An examina-
tion of the types in the Victoria Memorial Museum at Ottawa,
Canada, shows that these types include two species, one of
which is described here as Tripteroceras pauquettense.

The siphuncle of Orthoceras hastatum was described by Bil-
lings as small, close to the centre of the ventral margin. The ab-
sence of any further description of the siphuncle suggests that,
at the time the original description of this species was being pre-
pared, the specimen here called Tripteroceras pauquettense did
not form part of the type series of Orthoceras hastatum, but was
added subsequently. The siphuncle of typical Orthoceras has-
tatum appears to be narrow, and not nummuloidal. Omitting
this one word, nummuloidal, the remainder of Hyatt^s descrip-
tion of the genus Tripteroceras will stand, with typical Ortho-
ceras hastatum as the genotype.

The conch is strongly depressed dorso-ventrally. The cross-
section is depressed subtriangular, with the ventral side distinctly

Hyatt, A., op. cit., p. 287.

232

'AUG. F. FOERSTE

flatter than the dorsal. The lateral sides are rapidly rounded.
The sutures form broad dorsal and ventral lobes. The lateral
saddles are relatively high. Usually the conch is straight,
though several specimens of Orthocevds hastatum are curved
slightly lengthwise. In Hyatt’s generic description the conch is
described as having the whorl arcuate in the young.

30. TRIPTEROCERAS HASTATUM (BILLINGS)

PLATE XXXI, FIGS. 3A, B, C, D

Orthoceras hastatum Billings, Geol. Surv. Canada, Rep. Progr. for
1853-56, published in 1857, p. 333

Original Description : Shaped like a Theca, two-edged ; ventral
side broad and almost flat, slightly convex; dorsal aspect most
convex along the center, thence sloping to the sides, which are
perpendicular to the ventral aspect, and nearly flat in the larger
portion of the shell. The section is thus a low, broad-based tri-
angle, with the angle at each end truncated, and with the apical
angle rounded. At a lateral diameter of eleven lines the height
or dorso-ventral diameter is six lines; the rate of tapering is
about 4 lines to the inch, measuring the inclination of the sides ;
the ventral and dorsal aspect approach each other at the rate of
two lines and a-third to the inch; siphuncle small, close to the
centre of the ventral margin ; the septa are curved in a circle of
which the radius is about half-an-inch, their distance from each
other has not been satisfactorily ascertained ; near the apex the
sides consist of two rounded edges, but in the direction of the
aperture these become more and more broadly truncated, until
at a diameter of eleven lines they have a perpendicular width of
about two lines. The surface is coarsely striated transversely,
and, at the dorsal ridge, the striae appear to make a bend toward
the aperture.

Locality and Formation. — Black River and Trenton limestone,
Pauquette’s Rapids, Ottawa City.

Five specimens, numbered 1281, and lettered a, b, c, d, and e
respectively, are in the Victoria Memorial Museum. Of these,
specimen 1281a is regarded here as the type, since it is 11
lines wide; a septum truncates its upper end. Specimen 1281c,
with a septum at its lower end, comes next in size. Specimen
1281d, here figured, shows the lengthwise curvature at its apical
end, with the concave curvature on its dorsal side; it is ter-

AMERICAN PALEOZOIC CEPHALOPODS

233

minated both at top and bottom by a septum. Specimen 1281b
is smaller, but shows a similar lengthwise curvature. Specimen
1281e shows the apical end. (Specimen 1281 is described here
as Tripteroceras pauquettense, and does not properly belong to
the type series of Orthoceras hdstatum.)

The conch of specimen 1281d, here figured, enlarges with a
lateral apical angle of 20°. The ventral side is strongly flattened.
The dorsal side shows a slight tendency toward angularity
along its median line. From this median line toward the lateral
angles, the dorso-lateral sides are slightly flattened. The lateral
angles are abruptly rounded. Toward the apical end, the speci-
men is gently curved lengthwise. The sutures of the septa curve
evenly downward on both the dorsal and the ventral sides. The
siphuncle is close to the ventral side, but its structure is un-
known. The lines of growth are almost directly transverse
around the entire specimen, but on the ventral side their direc-
tion is very slightly concave upward, and on the dorsal side
there is a corresponding but almost imperceptible concave curva-
ture which is interrupted medially by an almost imperceptible
convex curvature.

31. TRIPTEROCERAS PAUQUETTENSE SP. NOV.

PLATE XXXI, FIGS. 2A, B, C, D

Orthoceracone strongly compressed ; at its upper end the
lateral diameter is 24 mm. and the dorso-lateral one is 15 mm.
The cross-section is slightly subtriangular, owing to the smaller
convexity of the ventral side. The dorsal side is quite regularly
rounded and forms about two-fifths of a circle having a radius
of 13 mm., while the ventral side forms about one-fifth of a
circle having a radius of 20 mm. The lateral margins are rap-
idly rounded. The center of the siphuncle is 4 mm. from the
ventral wall. It enlarges from a diameter of 4 mm. at the septa
to 5 mm. at mid-height within the camerae. Its passage through
the septum is 1.5 mm. in diameter.

The specimen is 25 mm. in length. Six camerae occur in a
length of 24 mm. On the ventral side of the conch, the sutures
of the septa curve strongly downward toward the median line,
but, on approaching the lateral outline of the conch, this curva-
ture of the sutures becomes slightly convex. Along the median
line of the ventral side the downward curvature of the sutures

234

AUG. F. FOERSTE

is slig'htly angular. On the dorsal side of the conch, the down-
ward curvature of the sutures is more moderately and more
evenly concave. The lateral outlines of the conch diverge at
an angle of 11°. No growth lines are preserved on the exterior
of the shell.

Locality and Horizon. — Pauquette Rapids, in the Ottawa River,
Canada ; in the Leray member of the Black River.

Remarks. — The specimen here described is numbered 1281 in
Victoria Memorial Museum, at Ottawa, Canada, and is there
found among the types of Orthoceras hastatum Billings, from
which it is here separated as a distinct species.

The specimen here described as Tripteroceras pauquettense
probably is distinct generically from typical Tripteroceras. The
latter probably contains only species with moderately expanded
siphuncular segments, species with nummuloidal segments prob-
ably being referable to a distinct genus.

32. CHARACTOCERAS GEN. NOV.

Genotype: Trochoceras (?) baeri Meek and Worthen. Proc. Acad. Nat.

Sci. Philadelphia, 1865, p. 263; Meek, Geol. Surv. Ohio, Pal.,

1, 1873, p. 157, pi. 13, fig. 9.

Conch nautiloid, depressed dorso-ventrally, the dorsal side
being impressed at contact with the ventral side of the preceding
volution. The transverse striae indicate that the margin of the
aperture curved increasingly downward from the dorsal side of
the conch toward its ventral side, the hyponomic sinus being
broad and relatively deep, but not abrupt. The sutures of the
septa curve moderately downward laterally, rising farther on the
ventral than on the dorsal side. The siphuncle is located near
the ventral side, but not in contact with the latter. The seg-
ments of the siphuncle are somewhat between subfusiform and
elongate elliptical in outline.

The conch of Uranoceras Hyatt is compressed laterally, and
there is no dorsal furrow, although adjacent volutions often are
so close as to touch each other. The sutures of the septa are
more sinuous laterally, at later stages of growth. The siphuncle
is only slightly ventrad of the center of the conch, and the down-
ward curvature of the septal necks is distinct. The form of the
segments is elongate cylindrico-elliptical. The genotype is
Uranoceras urannm Barrande, from the Silurian of Bohemia.

AMERICAN PALEOZOIC CEPHALOPODS

235

In Litoceras Hyatt, the cross-section of the conch is broadly
kidney-shaped; the ventral side presents a semicircular outline,
which rounds rapidly into the broadly impressed dorsal side of
the conch. The siphuncle is located distinctly dorsad of the cen-
ter, except in younger stages of growth. Since the genotype,
Litoceras whiteavesi Hyatt, is from the Canadian of Newfound-
land, it may be assumed that the segments of this siphuncle were
curved cylindrical, and not elongate elliptical or subfusiform in
outline. Litoceras does not occur in the Richmond formation.

Charactoceras includes also Nautilus Hercules Billings, from
the Charleston formation (Richmond) of Anticosti. Eurysto-
mites plicatus Whiteaves, from the Lake Winnipeg area, appar-
ently is congeneric.

33. CHARACTOCERAS BAERI (MEEK AND WORTHEN)

PLATE XXXI, FIG. 1; PLATE XXXII, FIGS. lA, B; PLATE XXXIII,
FIGS. lA, B; PLATE XXXIV, FIGS. lA, B, 2

Trochoceras (?) Baeri Meek and Worthen, Proc. Acad. Nat. Sci.

Philadelphia, 1865, p. 263. Meek, Geol. Surv. Ohio, 1, 1873,
p. 157, pi. 13, fig. 9.

Tijpe specimen. — The type was collected at Richmond, Indiana.
It con-sisted of a phragmacone, defective on one side, showing
neither surface structure, nor the siphuncle. The dorsal side of
each volution is impressed distinctly by the ventral side of the
preceding volution. The type is illustrated in volume 1 of the
Paleontology of Ohio, and in this volume it is stated that frag-
ments from the same locality and position as the type have the
siphuncle located rather more than its own breadth outside of the
center. Better specimens, collected by Prof. W. H. Shideler from
the Richmond at Oxford and vicinity are described in the fol-
lowing lines.

Oxford specimens. — Maximum diameter of the largest well
preserved specimen found, (Plate XXXI, Fig. 1; Plate XXXII,
Figs. 1 A, B; see also Plate XXXIH, Figs. 1 A, B), from the
ventral margin of the aperture to the opposite side of the last
volution, 150 mm. ; diameter at right angles to the latter, also
across the umbilicus, 113 mm. Lateral diameter of the living
chamber at the base of the hyponomic sinus, 93 mm. ; dorso-
ventral diameter at the same point, 66 mm. Length of living
chamber from suture at base to lower part of hyponomic sinus,
measured along the ventral side, about 100 mm. ; length to highest

236

AUG. F. FOERSTE

part of the lateral margins of the aperture, measured along the
median part of the lateral sides, about 108 mm. Depth of
hyponomic sinus below level of highest part of lateral margins
of aperture, 36 mm.

At the base of the hyponomic sinus the lateral diameter of the
living chamber is 93 mm. ; 100 mm. farther down, measured
along the ventral side of the conch, this diameter is 83 mm.;
100 mm. still farther down it is 67 mm. ; indicating a rate of
diminution of 10 and 16 mm. respectively in the distances men-
tioned. Estimating the remainder of the length of the last volu-
tion, in an apicad direction, as 120 mm., the lateral diameter of
the conch at the beginning of its last volution, was at least as
small as 47 mm., but probably was smaller, since the< rate of
diminution of the lateral diameter of the conch appears to have
been greater in an apicad direction. In fact, in some specimens,
which show parts farther apicad, the rate of diminution of parts
narrower than 47 mm. equals 25, and occasionally even 28 mm.
in a length of 100 mm. The apical end of the conch has not been
discovered, but it is estimated that the large conch here described
included at least 2 complete volutions and possibly more or less
of a third volution. The umbilicus may have been penetrated by
a perforation about 10 mm. in diameter, but this part is not
well preserved in any specimen.

The conch is depressed dorso-ventrally, the general outline of a
cross-section of the larger volution being transversely elliptical,
with the dorsal side distinctly and broadly impressed. The ratio
of the dorso-ventral to the lateral diameter varies from 67 % to
70% in different specimens. The ventral side is less strongly
curved than the dorsal, the maximum curvature of the lateral
sides being slightly nearer the ventral side of the whorl. In
general, the lateral sides of the whorl converge toward the
dorsal side. In one specimen, with a width of 66 mm. at the
base of the living chamber, the width of the impressed zone at
this point was 25 mm., its depth being 4 mm. In its original
condition the conch was symmetrical, but, in the fossil state,
one of the lateral sides often is flattened slightly or more dis-
tinctly; usually on that side of the specimen which, in the
original position of the fossil in the rock, faced downward. In
those specimens in which one of the lateral sides is flattened, the •
opposite side usually shows the normal transverse convexity.

AMERICAN PALEOZOIC CEPHALOPODS 237

The number of camerae in a length equal to the lateral diameter
of the conch, varies in different specimens. In the large speci-
men described above, 7 camerae occur in this length, if measured
along the ventral side of the conch. Specimens with 6 camerae
in this length are more common, and a few specimens with 5
camerae in this distance occur. Close study fails to show any
specific differences accompanying this variation in the relative
number of camerae.

The sutures of the septa rise moderately from the dorsal
toward the ventral side of the conch, the amount of this rise
varying from slightly more than the height of one camera, along
the ventral side, to about one and a half camerae. Along the
lateral sides these sutures curve slightly downward, forming
very shallow lobes, readily detected only toward the upper part
of the phragmacone. Along the ventral side the sutures arch
•moderately upward, producing low, broad saddles. The middle
part of these saddles tends to be less curved than the lateral
parts, and in some specimens there is a faint downward curve of
the sutures along the median line of the ventral side, but this is
by no means a constant feature.

The septa are moderately concave, their curvature being
greater dorso-ventrally than laterally. The siphuncle is located
on the ventral side. Its distance from this side varies from one-
fifth to two-sevenths of the dorso-ventral diameter.

In the specimen from Flat Fork, (Plate XXXIV, Fig. 2),
three and a half miles northeast of Oregonia, Ohio, the center of
the siphuncle is 5.5 mm. distant, where the dorso-ventral diam-
eter is 36 mm. The segments of the siphuncle vary from 5.5 to
6 mm. in diameter dorso-ventrally, at mid-height of the camerae,
diminishing to 4, or even 3 mm. where in contact with the septa,
the passage through the septa being still narrower. Along the
dorsal side of the siphuncle, the vertical outline of the segments
is more evenly convex; but along the ventral side the vertical
outline is distinctly convex above and concave below, the con-
cave part being adnate to the septa beneath for a length of 3 to
5 mm. The upper part of the dorsal outline of some of the seg-
ments is adnate for a length of 1 to 3 mm. to the overlying septa,
while in other segments no adnation is noted. The septal neck of
this specimen appears to be very peculiar in construction. On
the dorsal side of the siphuncle the septum maintains an even

238

AUG. F. FOERSTE

rate of curvature as far as the most constricted part of the
exterior wall of the siphuncle, and then appears to continue into
the interior of the siphuncle for a distance of 1 mm., bending
downward at an angle of 25° with a direct continuation of its
course. On the ventral side of the siphuncle the septum curves
gradually downward where in contact with the lower half or
third of the overlying segment of the siphuncle, until reaching
the most constricted part of the exterior wall of the siphuncle,
beyond which it appears to extend into the interior of the
siphuncle about half a millimeter in a direction toward the sim-
ilar extension of the dorsal part of the septum. As a result the
open passage through the center of the siphuncle appears to be
constricted here to a narrow opening varying from 2 to 3 mm.
in diameter. This constriction of the interior of the siphuncle,
beyond the amount of constriction indicated by the exterior wall
of this siphuncle, is not noted in all specimens, though traces of
such constriction occur also in several of the segments in speci-
mens obtained at Four Mile creek, near Oxford, Ohio. It is not
regarded as a constant feature. Apparently it is not strictly a
part of the septa, but was formed subsequent to the latter.

In some specimens from 8 to 10 of the upper camerae are con-
siderably shorter in length than the camerae beneath, indicating
a rather long period of gerontic growth.

The surface of the shell is transversely striated by lines which
tend to occur at regular intervals, about 16 in a length of 20 mm.
where the lateral diameter is 85 mm. Since similar distances
obtain also toward the apical end, where the diameter is much
less, the striae here appea-r relatively more distant. In some
specimens the striae are more numerous, equalling 20 and even
24 in a length of 20 mm. In general, these striae are of the
^‘banded” form, or they may be very narrow and sharply defined,
and separated by much broader flat areas. These transverse
striae follow the same course as the former limits of the aper-
ture. Along the median part of the dorsal side they are nearly
directly transverse, but dorso-laterally they curve increasingly
downward, their ventral course being broadly concave, forming
broad and deep lobes here, whose bases lie about 5.5 camerae
below the level of these striae on the dorsal side of the conch.
These lobes mark former positions of the hyponomic sinus.

Locality and Horizon. — This species was described from Rich-

AMERICAN PALEOZOIC CEPHALOPODS

239

mond, Indiana. The large specimen forming the basis of most of
the description here presented was obtained on Dodge's Fork,
near Oxford, Ohio, at the base of the Whitewater member of
the Richmond formation. Numerous specimens from the same
horizon, on Little Four Mile creek, also near Oxford, furnished
additional material, including sections of the siphuncle. How-
ever, most of the details of the structure of the siphuncle here
presented were obtained from a specimen collected by Prof. J. E.
Carman on Flat Fork, three and a half miles northeast of Ore-
gonia, Ohio, at the base of the Whitewater. The specimens from
the vicinity of Oxford belong to Miami University and were col-
lected by Professors W. H. Shideler and S. R. Williams.

A closely similar, if not identical, species occurs at the base of
the Rhynchotrema dentata bed in the Upper Whitewater, on
Beasley Run, north of Camden, Ohio.

Specimens resembling Charactoceras haeri occur in the Fern-
vale member of the Richmond at Wilmington, Illinois, and Cape
Girardeau, Missouri.

34. ONCOCERAS HALL

Genotype: Oncoceras constrictum Hall. Pal. New York, vol. 1, 1847,
p. 197, pi. 41, figs. 6 a-f, 7 a-d

Conch curved lengthwise; the lengthwise curvature of the
ventral side is convex, and the general curvature of the dorsal
side is concave, but along the upper part of the phragmacone
and the lower part of the living chamber the vertical outline of
the dorsal side changes to distinctly, though moderately, convex.
The gibbosity of the dorsal side of the conch usually extends also
laterally sufficiently to be noticeable when the conch is exam-
ined from the ventral side. The conch is slightly compressed
laterally. The living chamber narrows toward the aperture,
which is broadly oval in outline, the angularity being on the
ventral side. The hyponomic sinus is shallow. The siphuncle
is close to the ventral wall of the conch, and its segments are nar-
rowly fusiform.

Oncoceras abruptum Hall, Gomphoceras cincinnatiense Miller,
Oncoceras douglassi Clarke, Oncoceras pristinum Ruedemann,
and Orthoceratites trentonense Emmons are congeneric. The
last named species from the Trenton of New York apparently is
identical with Oncoceras constrictum, Gomphoceras faberi

240

AUG. F. FOERSTE

Miller may belong here, though its dorsal outline is only faintly
convex.

35. ONCOCERAS CONSTRICTUM HALL
PLATE XXXIX, FIGS. 2A, B, 3, 4

Oncoceras constrictum Hall, Pal. New York, vol. 1, 1847, p. 197, pi. 41,

figs. 6 a-f, 7 a-d

Type. — Among the specimens figured by Hall that represented
by figures 6 a, b, c may be selected as the type, not only because
it is the first in the series of illustrations, but also because it is
the largest, and evidently is a fairly typical example of the species
as noiv knoivn.

Conch curved lengthwise, slightly compressed laterally, and
distinctly gibbous at the base of the living chamber and the top
of the phragmacone, the gibbosity being conspicuous dorsally as
well as laterally and ventrally. The radius of convex curvature
of the vertical ventral outline is 30 mm. for the greater part of
the length of the specimen, but at its apical end the rate of curva-
ture is slightly greater. The dorsal side has a general concave
curvature with a radius of 45 mm., but for a distance of 8 or 9
mm. both above and below the base of the living chamber the
dorsal outline changes to slightly convex, producing a conspicu-
ous gibbosity here. Toward the apical end of the specimen the
rate of concave curvature increases to a radius of less than
20 mm.

The conch is compressed laterally. At the base of the living
chamber, where the dorso- ventral diameter is 24 mm., the lateral
diameter is 20 mm. Toward the aperture the conch contracts
not only dorso-ventrally but also laterally. At the aperture the
dorso-ventral diameter is 18 mm. Since the living chamber of
the specimen here described is crushed laterally, it is not suitable
for showing the rate of lateral contraction toward the aperture,
but in better preserved specimens the rate of contraction later-
ally is greater than that dorso-ventrally, resulting in a slightly
oval outline of the aperture. The curvature of the conch in a
transverse direction is even on the dorsal side of the conch, but
tends to be faintly angular on the median part of the ventral
side.

The base of the living chamber is exposed by a fracture. The
height of the living chamber is about 20 mm. That part of the
phragmacone which remains attached to the living chamber is

AMERICAN PALEOZOIC CEPHALOPODS

241

24 mm. long. At the broken base the dorso-ventral diameter is
12 mm.

The septum at the base of the specimen curves gently dorso-
ventrally, and curves even less laterally. The result is that the
sutures of the septa form comparatively shallo^v lateral lobes.
Along the dorsal side of the conch the sutures are almost directly
transverse, but along the ventral side they rise into more or less
distinctly angular saddles. The siphuncle is small, and is located
less than 1 mm. from the ventral wall even along the upper part
of the phragmacone. The number of camerae in a length equal
to the dorso-ventral diameter in another specimen is about 8,
and in still another specimen the segments of the siphuncle are
seen to be narrowly fusiform.

Figured specimens. — The originaP^^ of figures 3 a, b, on plate 3
of the Third Report of the New York State Museum, published
in 1850, shows the surface striae very well. These striae are
directly transverse along the dorsal and lateral sides of the conch
as far as the middle of the lateral sides. Ventrad of these middle
points the transverse lines curve gradually downward until they
meet along the median part of the ventral side at an angle of
about 130° in the vicinity of the aperture. The hyponomic sinus
is broadly V-shaped, and its depth equals 2 or 3 mm. Judging
from these transverse striae, the aperture was about 15.5 mm.
long, dorso-ventrally, 12.5 mm. wide, and had a distinctly
angular outline at the hyponomic sinus.

The strongly concave lengthwise curvature of the upper part
of the dorsal outline of the living chamber in the specimens rep-
resented by figures 6d and 6e, on the plate accompanying the
original description, probably is due in large part to pressure,
both specimens being preserved in a rather soft argillaceous
limestone.

In some specimens the cast of the interior of the phragmacone
and of the lower half of the living chamber is marked by about
35 faint vertical ribs, none of which correspond to any structure
on the exterior of the shell.

Locality and Horizon. — All of the specimens described here are
from Middleville, New York, in the Trenton limestone. Num-
bered 824 in the American Museum of Natural History.

This Journal, PL XXXIX, figs. 2A, B.

242

AUG. F. FOERSTE

36. MAELONOCERAS HYATT
Genotype: Phragmoceras praematurum Billings

Laterally compressed cyrtoceracones, with the ventral side
more narrowly rounded than the dorsal. The living chambers
are short, and their apertures, in the typical specimens, are con-
tracted and pear-shaped. The sutures of the septa curve slightly
downward laterally. The siphuncle is near the ventral side, and
its segments are narrowly fusiform.

Cyrtoceras metellus Billings from the Canadian of Point Levis,
in the province of Quebec, Cyrtoceras falx Billings from the
Black River of Pauquette Rapids, in Ontario, and Cyrtoceras
arctioameratum Hall from the Guelph of Ontaria are not con-
generic with Maelonoceras praematurum. Possibly the form
figured by Whitfield under Cyrtoceras camurum (Geol. Wis-
consin, 4, 1882, p. 231, pi. 7, figs. 7-9) is a true Maelonoceras.

37. MAELONOCERAS PRAEMATURUM (BILLINGS)

PLATE XXXIX, FIGS. 6 A, B, C; PLATE XLI, FIG. 7
Phragmoceras praematurum Billings; Canadian Naturalist, vol. 5,
1860, p. 163, figs. 20

Maelonoceras praematurum Hyatt; Proc. Boston Soc. Nat. Hist.,
vol. 22, 1884, p. 280

Two specimens belong to the set described by Billings under
the name Phragmoceras praematurum, and both were figured.
The specimen represented by figure 20, accompanying the orig-
inal description, shows most of the details included in this de-
scription, and hence is here regarded as the type.

Type. — Conch strongly compressed laterally, and strongly
curved length-wise, the siphuncle being close to the ventral side.
The conch attains its greatest dimensions 5 mm. above the base
of the living chamber. Here its lateral diameter is 16 mm. and
its dorso-ventral one is 18.5 mm. The conch is more narrowly
rounded on its ventral side, the radius of transverse curvature
here being 5 or 6 mm., while that of the dorsal side is 8 mm. The
convex lengthwise curvature of the ventral side has a radius of
25 mm., and that of the concave curvature of the dorsal side is
about the same, at least within the limits of the type specimen.

The latter consists of the living chamber with 5 complete cam-
erae attached. In addition, parts of 2 camerae prolong the dorsal
outline of the specimen. The upper half of the living chamber
narrows toward the aperture, where the lateral diameter is

AMERICAN PALEOZOIC CEPHALOPODS

243

12 mm., and the dorso-ventral one is 14 mm. In addition, the
aperture is narrowed by two low but distinct ventro-lateral sad-
dles, which rise above the level of the dorsal outline of the
aperture and converge more or less toward each other. In the
vicinity of these saddles the dorso-ventral parts of the living
chamber are more or less flattened. The general outline of the
aperture is pear-shaped, with the narrow part on the ventral side.

The upper part of the interior of the living chamber is dis-
tinctly constricted by a thickening of the shell. Along the dorsal
and lateral sides of the aperture this thickening begins 3 mm.
beneath the margin ; along the ventral side it begins about 1 mm.
beneath the aperture.

Along the ventral side, 5 camerae occupy a total length of

13 mm. The sutures of the septa rise slightly from the dorsal
toward the ventral side of the conch. The sutures are nearly
straight, their downward curvature along the lateral sides of the
phragmacone being very faint. The general concavity of the
septa is slight, equalling scarcely 1 mm. The siphuncle is about
one-third of a millimeter from the ventral wall. Its lateral
diameter, where passing through the septa, is 0.7 mm., widening
to about 0.9 mm. within the camerae, the general form of its
segments being only slightly fusiform.

The shell is relatively thick, equalling nearly 1 mm. along the
dorsal and dorso-lateral parts of the upper half of the living
chamber, and nowhere thinning to less than half a millimeter.

The transverse striae are merely lines of growth. Along the
lower half of the living chamber these lines are almost directly
transverse along the dorsal half of the circumference of the
chamber ; but on the ventral side they curve distinctly downward
as far as the median part of this side. However, toward the
upper part of the living chamber, the transverse striae rise more
and more strongly from the dorsal toward the ventro-lateral
parts of the conch, outlining successive stages in the development
of the ventro-lateral saddles, which gradually increase in promi-
nence until they attain an elevation of 2.5 to 3 mm. above the
general level attained by the aperture along its dorsal side.
From the crest of these saddles the lateral margins of the hypo-
nomic sinus slope diagonally downward as far as its ventral end
which descends 1 mm. or more beneath the general level at-
tained by the dorsal side of the aperture. The general form of

244

AUG. F. FOERSTE

the aperture is pear-shaped, with the narrow end on the ventral
side. There is a tendency toward parallelism between the lateral
walls of the hyponomic sinus, somewhat as in Gomphoceras.

Locality and horizon. — Black River limestone on LaCloche
Island, in northern Lake Huron. Specimen No. 1294 in the Vic-
toria Memorial Museum, at Ottawa, Canada.

38. MAELONOCERAS BILLINGSI SP. NOV.

PLATE XXXIX, FIGS. 5 A, B, C

Phragmoceras praematurum Billings, Canadian Naturalist, vol. 5, 1860,

p. 163, fig. 19 only

The second specimen figured by Billings under the name Phrag-
moceras praematurum differs from the one here described as the
type in having a shorter and straighter living chamber. It is
assumed that the conch was much less curved lengthwise. More-
over, the dorsal half of the aperture is more nearly circular and
the lateral walls of the hyponomic sinus are more nearly parallel.

Locality and horizon. — Lacloche Island, in the northern part
of Lake Huron, in the Black River formation. Specimen No.
1294a, in the Victoria Memorial Museum, at Ottawa, Canada.

39. BELOITOCERAS GEN. NOV.

Type: Oncoceras pandion Hall

The group of conchs typified by Oncoceras pandion differs
from typical Oncoceras in lacking a distinct gibbosity along the
upper part of the phragmacone and the lower part of the living
chamber. If any gibbosity along the dorsal side is present, the
maximum development of this gibbosity is distinctly above the
level of the base of the living chamber. Moreover, compared
with typical Oncoceras, the conch is distinctly more flattened
laterally.

The relationship of the group typified by Oncoceras pandion
is with Maelonoceras rather than with Oncoceras. Like the lat-
ter, it is more strongly flattened laterally, and the interior of the
living chamber is thickened below the margin of the aperture
by an inner band which leaves a conspicuous contraction along
casts of the interior of the conch. The aperture has an outline
corresponding to that possessed by Maelonoceras during its
earlier stages of growth, before the ventro-lateral saddles begin

AMERICAN PALEOZOIC CEPHALOPODS

245

to develop. In other words, Beloitoceras may be regarded as the
stock from which Maelonoceras developed.

Cyrtoceras mrrollense Worthen, Oncoceras carvieri Clarke,
Cyrtoceras fragile Billings, C. houghtoni Clarke, C. huronense
Billings, C. isodorus Billings, C. norwoodi Clarke, and C. scofieldi
Clarke are congeneric; probably also an equal number of other
described species of which the living chamber is not well known.

Cyrtoceras dunleithense Miller and Gurley, and C. cordatum
Parks are characterized by the ridge-like protrusion of the siph-
onated Side of the conch, and for these the generic term Dun-
leithoceras is proposed.

40. BELOITOCERAS PANDION HALL

PLATE XXXVI, FIGS. 5 A, B; PLATE XLI, FIGS. 4 A, B, C
Oncoceras pandion Hall; Rep. Sup. Geol. Surv. Wisconsin, 1861,
p. 45, ibid, 1862, p. 41, fig. 3

Oncoceras pandion Whitfield; Mem. Amer. Mus. Nat. Hist., vol. 1,
pt. 2, 1895, p. 69, pi. 9, figs. 21, 22

• Type. — Conch strongly curved lengthwise, especially along its
ventral side, where the radius of convex curvature is only 30 mm.
Along the dorsal side the radius of concave curvature is 40 mm.
The specimen enlarges from a dorso-ventral diameter of 19 mm.
at its base to 25 mm. at the base of the living chamber. It
diminishes to 22.5 mm. along a line drawn from 10 mm. above
the base of the dorsal side of the living chamber to 14 mm. above
the base of this chamber on the ventral side. Then this diameter
diminishes rather abruptly, to 21 mm. within a distance of 3 mm.,
and to 20 mm. within an additional distance of 4 mm., above
which the margin of the aperture is assumed to be. The cor-
responding lateral diameters are 16 mm. at the base of the speci-
men, 23 mm. at the base of the living chamber, 20 mm. where the
abrupt contraction of the upper part of the living chamber be-
gins, 16.5 mm. at a point 3 mm. farther up, and slightly less at
the aperture. The sudden constriction of the cast of the interior
of the living chamber near the aperture indicates the presence of
a corresponding thickening of the interior of the wall of this
chamber just beneath the aperture.

There is no trace of a gibbosity along the dorsal outline of the
conch at the base of the living chamber, though the amount of
concave curvature here is distinctly less. The cross-section of
the conch tends to be slightly more narrowly convex on the ven-

246

AUG. F. FOERSTE

tral than on the dorsal side, especially toward the living chamber,
and most of all at its aperture, where the difference is strongly
marked, resulting in the oval outline of the aperture. Faint,
low, broad vertical ribs mark the cast of the interior of the
conch ; these number about 5 in a width of 11 mm., near the top
of the phragmacone.

The number of camerae in a length equal to the dorso-ventral
diameter, at the top of the series of camerae counted, is 7, when
counted along the ventral side of the conch. The sutures of the
septa are only slightly concave, most of the curvature being ven-
trad of the center of the conch. At the base of the specimen the
upward curvature of the sutures is chiefly ventrad of the ventro-
lateral sides. Toward the top of the phragmacone the upward
curvature of the sutures begins progressively nearer the middle
of the lateral sides, and the amount of the upward curvature on
this ventrad side also becomes greater, the ventral saddles be-
coming successively higher. The siphuncle is almost in contact
with the ventral wall of the conch. Its maximum width at the
bottom of the specimen, within the camerae, is 3 mm., diminish-
ing to about 1 mm. where it passes through the septa.

Locality and horizon. — Beloit, Wisconsin; in the buff part of
the Black River dolomite.

Specimen No. 998, in the American Museum of Natural His-
tory.

Mineral Point syecimen. — In addition to the type of Oncoceras
pandion, Whitfield figured also a similar specimen (his figure 20)
from a very fine-grained grayish rock at Mineral Point, Wis-
consin. Lithologically this rock resembles that enclosing the
type of Cyrtoceras neleum, from Platteville, Wisconsin. The
Mineral Point specimen is more compressed laterally, the dorso-
ventral and lateral diameters at the base of the living chamber
being 26.5 and 21.5 mm. respectively. Apparently the conch is
less strongly curved lengthwise, and the sutures of the septa
curved less strongly upward on the ventral side. The upper-
most camera is distinctly shorter than those beneath, the speci-
men being mature. The ventral side of the conch is more nar-
rowly convex in cross-section than the dorsal side, especially
toward the living chamber, and most of all near the aperture.

Janesville specimen. — -In the specimens from Janesville, Wis-

AMERICAN PALEOZOIC CEPHALOPODS

247

consin, figured by Clarke,^® the lengthwise curvature of the ven-
tral side of the conch is similar, but the concave curvature of the
dorsal side is greater, especially along the lower part of the
living chamber ; the conch is more compressed laterally, and the
sutures do not rise as strongly on the ventral side of the phrag-
macone.

Oncocevas carvieri Clarke®^ appears to be closely related to the
Platteville specimen figured by Whitfield under Oncoceras
pandion. It is characterized chiefly by its lateral compression,
and the fact that the living chamber is not so strongly con-
tracted toward the aperture.

41. BELOITOCERAS PLEBEIUM HALL
PLATE XXXVI, FIGS. 4A, B, 3 A, B; PLATE XLI, FIGS. 5A, B

Oncoceras plebeium Hall; Rep. Superintendent Geol. Surv. Wisconsin,

1861, p. 44

Oncoceras plebeium Whitfield, Mem. Amer. Mus. Nat. Hist., vol. 1, pt. 2,
1895, p. 68, pi. IX, figs. 16-19

The original description indicates that several specimens were
at hand at the time of description of this species. Of these Whit-
field figured three. The largest is selected as the type because it
bears the small lozenge-shaped yellow label, and retains a rem-
nant of the thin paper label which Hall used for indicating his
types among the species described in 1861. Moreover, this speci-
men is the first one of the three figured by Whitfield.^®

Selected type. — Specimen (Plate XXXVI, Figs. 4A, B; Plate
XLI, Figs. 5 A, B) consisting of the living chamber with 7 cam-
erae still attached. Conch rather strongly curved lengthwise in
a dorso-ventral plane ; the radius of convex curvature of the ven-
tral side, along the upper part of the phragmacone and along the
living chamber, is 45 mm. ; the radius of concave curvature of
the dorsal side, along the upper part of the phragmacone, is
30 mm. ; a very faint convexity extends from the base of the
second camera below the living chamber upward along the
greater part of the living chamber, but within 3 or 4 mm. from
the aperture the dorsal outline is slightly concave again. The
faint convexity along the lower part of the dorsal side of the liv-

Clarke, John M., The Lower Silurian Cephalopoda of Minnesota; Minn.
Geol. Survey, Final Rept., vol. 3, pt. 2, p. 799, pi. 58, figs. 4-6a, 1897.

Idem. p. 799, pi. 58, figs. 7-9.

Whitfield, R. P., Republication of descriptions of fossils from the Hall
collection; Mem. Am. Mus. Nat. Hist., vol., 1, pi. 9, figs. 15, 16, 1895.

248

AUG. F. FOERSTE

ing chamber is supposed to correspond to the much more pro-
nounced gibbosity of Oncoceras constrictum Hall, but it is located
farther up.

The dorso-ventral diameter enlarges from 19 mm., at the
base of the specimen, to 22 mm. at the base of the living chamber,
the latter being 19 mm. farther up along the ventral side of the
conch. At mid-height of the living chamber this dorso-ventral
diameter is still 22 mm., but at the constricted part, 3 mm. be-
low the aperture, it is only 20 mm., enlarging slightly above this
point. Since the specimen is a cast of the interior of the shell,
the apparent enlargement of the living chamber near its aperture
may be due chiefly to a thickening of the interior of the shell
there, - the exterior of the shell not showing any corresponding
expansion.

The conch is strongly compressed laterally, the lateral diam-
eter at the base of the specimen being 15 mm. ; at the base of the
living chamber it is 18 mm. ; about 2 mm. above this base it is

18.5 mm. ; and from this point upward it diminishes gradually,
until 3 mm. below the aperture, at the constricted part, it is

15.5 mm. ; above this constricted part it increases slightly. The
broadest part of the cross-section of the conch is distinctly dorsad
of its center, the ventral side being much more narrowly rounded
than the dorsal one, especially toward the aperture, whose con-
tour is distinctly oval in outline.

The sutures of the septa are directly transverse along the
dorsal side of the phragmacone, and this direction is maintained
along the dorso-lateral parts of the conch; but, on approaching
the middle of the lateral sides, the sutures curve progressively
more strongly upward, until they form an angle of about 75° with
the ventral outline, when the cast of the interior of the phrag-
macone is viewed from one of the lateral sides. The result is
the formation of distinct saddles along the ventral side of the
conch. The number of camerae, in a length equal to the dorso-
ventral diameter of the conch at the top of the series of camerae
being counted, is 8, when the counting is done along the ventral
side. When compared with the corresponding lateral diameter,
this number of camerae is slightly greater than 6. The septa
are only moderately concave. The exterior of the cast of the
interior of the phragmacone is marked by faint traces of vertical
ribs, most readily detected on the dorsal side of the cast.

AMERICAN PALEOZOIC CEPHALOPODS

249

The siphuncle is almost in contact with the ventral wall of the
conch; it is moniliform in structure; its maximum diameter
within the camerae is 2.2 mm., diminishing to 1.5 mm. at its
passage through the septa.

Smaller specimen figured by Whitfield. — This specimen (Plate
XXXVI, Figs. 3 A, B) is illustrated by figures 18 and 19 among
the series published by Whitfield. It consists of the living
chamber with 9 camerae still attached. It is closely similar in
form to the larger specimen figured by Whitfield, but its dorso-
ventral diameter at the base of the living chamber is only 17
mm. instead of 22 mm., and its lateral diameter is largest (15.5
mm.) fully one-third of the height of the living chamber above
its base, where the diameter is 14.5 mm. The phragmacone ap-
pears to enlarge more rapidly in size, and the concave curvature
of the sutures of the septa along the middle of the lateral sides is
much less conspicuous. On the contrary, these sutures rise
slightly even along the dorso-lateral sides of the phragmacone
and their rise is only moderately accentuated along the middle of
the lateral sides, but they form about the same angle with the
ventral outline of the phragmacone. In the smaller, as well as
in the larger specimen here described, the sutures form pro-
gressively more acute angles on approaching the upper part of
the phragmacone.

Phragmacone figured by Whitfield. — This specimen is illus-
trated by figure 17 of the series published by Whitfield. It
apparently belonged to a mature individual, judging from the
distinct shortening of the uppermost camera, compared with the
camerae immediately beneath. Evidently, even the uppermost
camera of the phragmacone is preserved. It is significant, there-
fore, that the dorso-ventral diameter at the top of the specimen
is only 17 mm., in this respect agreeing more readily with that
of the smaller specimen figured by Whitfield. The sutures of the
septa rise even more strongly toward the ventral side of the
conch. The height of the camerae is distinctly greater, 7 cam-
erae occurring in a length equal to the dorso-ventral diameter,
in place of 8, when this length is measured along the ventral side
of the shell and the dorso-ventral diameter is measured at the
top of the series of camerae being counted.

Other specimens. — The Hall collection at the American Mu-
seum of Natural History includes five specimens in addition to

250

AUG. F. FOERSTE

those figured by Whitfield. Two of these retain enough of the
living chamber and of the attached part of the phragmacone to be
referred with confidence to Oncoceras pleheium. One of these has
a dorso-ventral diameter of 17 mm. at the base of the living
chamber, the other of 19.5 mm. A third specimen consists of a
body chamber, expanding toward the aperture as in Cyrtorizo-
ceras minneapolis (Clarke) and Cyrtorizocems scofieldi (Clarke).
Not enough remains of the other two specimens to make their
relationship to Oncoceras pleheium certain.

Locality and horizon. — Described from the “Buff limestone o-f
the Trenton limestone group, at Beloit,” Wisconsin. According
to Bassler’s Bibliographic Index, the horizon of this species is
the Platteville member of the Black River.

Types, No. 996, American Museum of Natural History, in
New York City.

Margin of the aperture. — One of the specimens in the Ameri-
can Museum of Natural History apparently presents features
both of the exterior and of the interior of the upper part of the
shell, but its chief interest lies in the fact that it retains a sharp
outline of the margin of the aperture. This margin is most
elevated along the middle of the lateral sides, and from this point
it slopes slightly downward both toward the dorsal and toward
the ventral side; however, the slope toward the ventral side of
the conch is slightly greater than that toward the dorsal side,
compared with the direction of the central axis of the living
chamber. The hyponomic sinus evidently is very shallow. When
viewed from above, however, the aperture contracted distinctly
ventrad of its center, as in the type of Oncoceras pleheium.

Along the dorsal half of the specimen, the living chamber is
contracted slightly but distinctly at a level about 5 or 6 mm. be-
low the margin of the aperture. Toward the ventral side this
contraction is scarcely 4 mm. from the margin of the aperture.
Above this point of contraction the specimen retains about the
same dimensions as far as the aperture. Since no trace of the
septa is shown by the specimen, this contraction appears to be
a feature of the exterior surface of the shell as well as of its
interior, but ordinarily it would be regarded as characteristic of
the interior of the living chamber alone, due to a thickening of
the interior of the shell along the line indicated.

Judging from the contours of the specimen, the height of the

AMERICAN PALEOZOIC CEPHALOPODS

251

living chamber, along the middle of its lateral sides, is 20 mm. ;
and the dorso-ventral diameter at this point is 20 mm., diminish-
ing to 19 mm. at the aperture.

This specimen is numbered 999B in the American Museum of
Natural History, and is incorrectly associated under this num-
ber with Oncoceras lycus. It was obtained at Beloit, Wisconsin,
at the same locality and horizon with the type of Oncoceras
plebeium.

Oncoceras lycum Clarke^® appears to be closely similar to
Oncoceras plebeium, as far as may be determined from the fig-
ures. The increase in concave curvature of the dorsal side near
the aperture and the straightening of the shell along the middle
and lower part of the dorsal side of the living chamber is char-
acteristic; the distance between the septa is similar ; also the
course of the sutures.

Cyrtoceras houghtoni Clarke^® may be the same as the smaller
specimen figured by Whitfield under Oncoceras plebeium. In
both figures 13 and 15 there is apparently a very faint trace of a
straightening or swelling along the lower two-thirds of the
living chamber. Moreover, the sutures of the septa are about
the same distance apart. The extreme lateral compression of
the conch shown by figures 14 and 14a is regarded as due to
fossilization, and not as characteristic of the shell in its original
state.

42. BELOITOCERAS LYCUM (HALL)

PLATE XXXVI, FIGS. 2 A, B

Oncoceras lycum Hall; Rep. Superintendent Geol. Surv. Wisconsin,

1861, p. 45

Onoceras lycus Whitfield; Mem. Amer. Mus. Nat. Hist., vol. 1,
pt. 2, 1895, p. 69, pi. IX, figs. 13, 14

Specimen consisting of a living chamber with 10 camerae still
attached. Conch moderately curved lengthwise in a dorso-ven-
tral plane ; the radius of convex curvature of the ventral side of
the phragmacone and of the lower half of the living chamber is
55 mm. ; the radius of concave curvature of the dorsal side of the
phragmacone is 40 mm. For a distance of 5 or 6 mm. below the^
base of the living chamber, and for an equal distance above the
base, the dorsal outline of the conch is nearly straight lengthwise,
suggesting a slight gibbosity of the dorsal outline of the lower

Clarke, op. cit., p. 799, pi. 58, figs. l-3a.

Idem. p. 807, pi. 59, figs. 12-15.

252

AUG. F. FOERSTE

half of the living chamber, follo’wed by a slightly concave length-
wise curvature along the upper half of this living chamber, in a
normal shell, somewhat as in Oncoceras plebeium Hall, from the
same locality and horizon as the type of Oncoceras lycum.

The specimen is a cast of the interior of the conch. In this
specimen the cast of the interior of the living chamber is con-
tracted abruptly and strongly near mid-height. The contraction
begins about 8 mm. above the base of this chamber and reaches
its maximum at 10 mm. above this base; above this level of
maximum contraction the cast expands evenly as far as the
aperture. The dorso-ventral diameter of this cast, at the base
of the living chamber, is 17 mm.; 8 mm. above the base it is
18 mm.; at the most narrowly contracted part of the chamber
it is 15 mm. ; and from this point of greatest contraction the cast
of the interior enlarges evenly to approximately 17 mm. at the
aperture, as far as can be determined from that part of the aper-
ture which is preserved. This abrupt and strong contraction
of the cast of the interior of the living chamber may not be indi-
cative of any corresponding contraction of the exterior of the
shell. On the contrary, it may be confined to its interior, and
may be due to a very gerontic thickening of the interior of the
living chamber, at mid-height, in case of some individual speci-
men; or, the animal after death may have contracted along the
upper half of the living chamber, as appears to have been the
case not infrequently in some Silurian Poterioceroids. The sym-
metrical contraction of this cast favors the first one of these
views, namely that the walls of the conch were thickened above
mid-height by a gerontic deposit upon their interior surface. If
this was the case, then the exterior of the living chamber may
have contracted toward its aperture very much as in Oncoceras
plebeium, from the same horizon and locality. In fact, Oncoceras
lycum may have differed from the type of Oncoceras plebeium
chiefly in its smaller curvature lengthwise, and in the greater
height of the camerae.

The phragmacone enlarges from a dorso-ventral diameter of
11 mm. at its base to 17 mm. at its top; the length of the phrag-
macone,- measured along its ventral side, is 22 mm. According
to this rate of tapering, the total length of the conch probably
did not exceed 75 mm., when measured along its ventral side.
The lateral diameter of the specimen at its base is 9.8 mm., and

AMERICAN PALEOZOIC CEPHALOPODS

253

at the top of the phragmacone it is 15.5 mm., indicating a mod-
erate lateral compression of the conch. There is a slight ten-
dency toward angularity in the cross-section of the conch, along
the median line of its ventral side, especially toward the top of
the phragmacone.

Counting along the ventral side of the conch, there are 7 cam-
erae in a length equal to the dorso-ventral diameter of the conch
at the top of the series of camerae being counted. The sutures
of the septa are directly transverse on the dorsal and dorso-
lateral sides of the conch, but they curve upward on approach-
ing the ventral side of the conch, producing low ventral saddles.

The siphuncle is close to the ventral wall of the conch. At
the base of the specimen, the diameter of the siphuncle, where it
passes through the septum, is slightly over 1 mm. Very faint
vertical ribs, easily escaping attention, mark the cast of the
interior of the phragmacone.

Locality and horizon. — Described from the “Buff limestone of
the Trenton limestone group referred by Bassler, in his Biblio-
graphic Index, to the Platteville member of the Black River.
The type specimen is labelled as coming from Beloit, Wisconsin.

Holotype. — No. 999, American Museum of Natural History, in
New York City.

Remarks. — The appearance of greater height in the camerae is
due chiefly to the small curvature of the conch lengthwise, owing
to which the septa are less closely crowded together on the dorsal
side of the conch, measuring only 5.5 camerae in a length
of 10 mm., instead of 8 camerae as in the smaller specimen of
Oncoceras plebeium figured by Whitfield.

43. WESTENOCERAS GEN. NOV.

Genotype: Cyrtoceras manitabense Whiteaves. Trans. Royal Soc.

Canada, vol. 7, sec. 4, 1890, p. 80, pi. 13, figs. 3-5; pi. 15, fig. 4

Conch slender, sub-fusiform, nearly straight along the dorsal
side, except at the aperture, but distinctly curved along the
ventral side. Aperture oblique, inclining downward from the
ventral toward the dorsal side. Sutures of the septa curving
strongly downward laterally, but rising dorsally and ventrally
into distinct saddles, which rise higher on the ventral than on
the dorsal side. Siphuncle nearer the ventral than the dorsal
side, described as “nearly cylindrical, but very slightly expanded
between the septa and as slightly contracted where it intersects

254

AUG. F. FOERSTE

them.” Further study of typical specimens is necessary to de-
termine the exact structure of the siphuncle.

44. POTERIOCERAS McGOY

Genotype: Orthoceras fusiforme Sowerby. See Foord, Garb. Foss,

Ireland, pi. 15

The name Poterioceras was proposed by McCoy for certain
Carboniferous species, the generic description being : '‘Shell fusi-
form. Mouth contracted. Siphuncle dilated between the
chambers, excentric.” Blake states that the diagram accompany-
ing this description is not justified by any known species, and
represents the aperture as very small but simple.

The species mentioned first in the body of the text is Poterio-
ceras fusiform (Sowerby) from Boland, Kildare. This was
founded on a specimen 6 inches long, 6 lines wide at the small
end, one inch and 7 lines wide at its largest diameter, and 9 lines
wide at the aperture.

A study of a specimen from Kildare, Ireland, numbered 2177
in the Museum of Comparative Zoology at Harvard University,
(Plate XLI, Figs. lA, B) indicates the following characteristics:

Conch fusiform, curved lengthwise, with the ventral side con-
vex, and the dorsal side concave, except along the upper part of
the phragmacone and the lower part of the living chamber
along the dorsal side, where the outline is distinctly convex or
gibbous. Toward the base of the living chamber the sutures rise
from the ventral toward the dorsal side of the conch. The
siphuncle is located a short distance ventrad from the center of
the conch. The septal necks are short and curve distinctly down-
ward and outward. The connecting rings are elongate elliptical
in outline. The aperture appears to have been circular in out-
line and its margin directly transverse. There may have been a
shallow hyponomic sinus, but this is not indicated by the speci-
men at hand. Conchs of this jtype do not occur in Silurian or
Ordovician strata,

Poterioceras fusiform (Sowerby) was figured by Foord^^ and
one of his illustrations is reproduced herewith (Plate XL, fig. 2).
Poterioceras latiseptum Foord^^ likewise shows the rise of the
sutures of the septa from the ventral toward the dorsal side of

Sowerby, Mineral Gonchology, pi. 588, figs. 1, 2.

Foord, Garb. Geph. Ireland, 1897, pi. 15.

^ Idem, pi. 16.

AMERICAN PALEOZOIC CEPHALOPODS

255

the conch. The siphuncle is between the center of the conch and
its ventral wall, and the segments of this siphuncle are more
nearly circular or slightly elongate in outline. Poterioceras ven-
tricosum McCoy apparently presents a different contour from
typical Poterioceras, as based on fusiforme.

45. AMPHICYRTOCERAS GEN. NOV.

Genotype: Cyrtoceras orcas Hall

Conch subfusiform, but curved lengthwise and depressed dorso-
ventrally. The ventral side of the conch is curved convexly,
and the dorsal side is concave except toward the upper part of
the phragmacone and the lower part of the living chamber, along
which it is gently convex or distinctly gibbous. The living
chamber contracts toward the aperture, and the margin of the
latter is nearly directly transverse dorsally and laterally, but
curves gently downward toward the median line of the ventral
side, where a shallow hyponomic sinus is located. The siphuncle
is near the ventral wall of the conch, but not in actual contact
with it. The septal necks curve distinctly downward, and the
connecting rings tend to be almost cylindrical in form, except at
their upper and lower extremities, where they contract abruptly.

The genotype, Cyrtoceras orcas Hall, is relatively common in
the Racine member of the Niagaran, at Racine, Waukesha, and
elsewhere in Wisconsin. Cyrtoceras laterale Hall, from the same
area and horizon, is congeneric. Oncoceras pettiti Billings, and
possibly Oncoceras thales Billings from the Niagaran of Ontario
also belong here. Strepoceras janus Billings and Streptoceras
heros Billings differ in having a protruding hyponomic sinus,
like an incipient lip.

46. AMPHICYRTOCERAS ORCAS (HALL)

PLATE XXIX, FIGS. 1 A, B, C

Cyrtoceras orcas Hall; Rep. Superintendent Geol. Surv. Wisconsin, 1862, p. 43
Oncoceras orcas Hall; 20th Rep. New York State Cab. Nat. Hist.,
1868, p. 350, pi. 17, figs. 1, 2

The type of this species, measured along the curvature of its
ventral side, is 143 mm. long. The living chamber appears to
occupy 57 mm. of this length, but there is a possibility that one
camera, whose upper septum is not exposed, is included in this
measurement. The upper three exposed camerae occupy a
length of 30 mm. ; the next three, 29 mm. ; and the lowest three.

256

AUG. F. FOERSTE

27 mm. At the uppermost exposed septum, the greatest width
of the phragmacone is 55 mm., but 10 mm. farther up the width
of the living chamber is 1 mm. greater. The smallest septum, at
the base of the specimen, has an estimated width of 25 mm. ; from
this point the conch widens along the entire length of the phrag-
macone. The living chamber narrows to 40 mm. at the aperture.
The general aspect, viewed from the ventral side, is subfusiform.
The conch is depressed dorso-ventrally. At the top of the phrag-
macone the ratio of the lateral to the dorso-ventral diameter is
55 to 50 mm. Toward the lower end of the phragmacone the
cross-section becomes more nearly circular.

The lengthwise curvature of the ventral side of the conch is
convex, with a radius of 105 mm. The lengthwise concave curva-
ture of most of the dorsal side of the phragmacone has a radius
of 90 mm., until within a short distance of the base of the living
chamber. At this upper level the general aspect of the shell is
tumid or swollen, the dorsal outline changing from concave to
slightly convex. In a general way, this convexity of outline ex-
tends from the base of the third camera beneath the living
chamber to mid-height of the latter, above which the dorsal out-
line is slightly concave again. The contraction of the living
chamber, both laterally and dorso-ventrally, is quite regular as
far as the aperture, with a very faint decrease in the rate of
contraction within 5 mm. of the margin of this aperture, in the
type, but not in other specimens of this species.

Septa with a concavity of 10 mm. occur at a point where the
width of the conch, not the type, is 54 mm. The sutures of the
septa appear to be nearly straight on the dorsal and lateral sides,
but incline slightly downward toward the ventral side. If there
is a tendency toward a slightly concave curvature of the sutures
on the ventral side, this is not known definitely, although sus-
pected from the inclination of the three septa seen on the ventral
side of the type, where part of the shell has spalled off. In
analogy with the species originally described as Cyrtoceras lat-
erale, the siphuncle is located on the ventral side of the conch,
about 3 mm. distant from the ventral wall.

The surface of the shell is crossed by low, broad, transverse
bands or lines of elevation of which 12 occur in a length of
20 mm. These bands are deflected downward on the ventral side
of the more inflated part of the conch for a distance of 3 mm.

AMERICAN PALEOZOIC CEPHALOPODS

257

and for a width of 25 mm., thus locating the hyponomic sinus
at earlier stages of growth. A partially exfoliated conch, num-
bered 3195 at the Public Museum of Milwaukee, Wisconsin, dis-
plays vertical bands and striae in addition to the transverse
bands.

Location and horizon, — In the original description of the
species, Racine is mentioned first as a source of material, but
the type is from Waukesha, Wisconsin. It is numbered 2112 in
the American Museum of Natural History.

Remarks, — In the 20th Report of the New York State Cabinet
of Natural History, cited above, the generic reference of this
species is changed from Cyrtoceras to Oncoceras, but the type of
the latter is a Trenton form, compressed laterally, not depressed
dorso-ventrally as in the Racine species here described. More-
over, the segments of its siphuncle are rather narrowly fusi-
form, instead of cylindrical or barrel-shaped in outline.

Numerous specimens of Amphicyrtoceras orcas are in the
Greene Museum at Milwaukee-Downer College, in Milwaukee,
Wisconsin.

47. AMPHICYRTOCERAS LATERALE (HALL)

PLATE XXX, FIGS. 1 A-D, 2 A, B

Cyrtoceras laterale Hall; 20th Rep. New York State Cab. Nat. Hist.,
1868, p. 357, pi. 18, figs. 4, 5, 6

Type, — Cyrtoceracone comparatively little curved. The length-
wise dorsal outline is nearly straight. The corresponding ven-
tral outline is curved lengthwise with a radius of 150 mm. The
specimen consists of a phragmacone, with only the basal part of
the living chamber still attached. The lateral diameter of the
phragmacone increases rapidly from 17 mm. at the base to
37 mm. at the top of the eighth camera from the smaller end.
From this point upward, for a distance of 4 camerae, the lateral
diameter remains about the same. The contraction near the base
of the living chamber is slight. At the smaller end of the phrag-
macone the transverse section is nearly circular, the dorso-ven-
tral diameter being 17 mm. Farther up, the conch rapidly be-
comes depressed dorso-ventrally. At the top of the eighth
camera, the cross-section is transversely elliptical, the dorso-ven-
tral diameter being 28 mm. The curvature of the conch in a lat-

258

AUG. F. FOERSTE

eral direction is slightly greater on the ventral than on the
dorsal side.

The sutures of the septa curve slightly downward along the
median parts of the ventral side, especially near mid-length of
the phragmacone. The location of the siphuncle at the smaller
end of the specimen is indicated by a small circle, 1.5 mm. in
diameter, with its center 3 mm. from the ventral wall of the
conch. Very faint, low. broad, almost obsolete vertical ribs,
about 7 in a width of 20 mm., are seen on casts of the interior
of the conch.

Locality and horizon. — From Racine, Wisconsin, in the Racine
member of the Niagaran. Specimen numbered 2119 in the
American Museum of Natural History.

Mihvaukee Museum specimen. — Another specimen, numbered
634 in the Public Museum of Milwaukee, Wisconsin, consists of
the living chamber and 6 upper camerae. The maximum width,
49 mm., occurs at the first camera beneath the living chamber.
The contraction of the upper part of the living chamber begins
8 mm. above the base of the latter. The height of this living
chamber is 44 mm. It contracts from a width of 49 mm. at its
base to an estimated width of 39 mm. at its top. The correspond-
ing dorso-ventral contraction is estimated from 44 mm. at its
base to 35 mm. at its top. The phragmacone is distinctly, though
gently, concave along its dorsal lengthwise outline. The sutures
of the upper septa slant slightly downward toward the ventral
side, and curve more strongly downward along the median part
of the latter, for a vertical distance of 3 or 4 mm. and for a
width of 25 mm. Farther down, the curvature of the sutures
becomes less conspicuous. The siphuncle is situated about
3 mm. from the ventral wall of the conch. Its segments are
somewhere between short cylindrical and barrel-shaped in ver-
tical outline. At the uppermost camera its diameter is almost
6 mm., diminishing at its passage through the septum to 3 mm.
The septal necks are short, about half a millimeter in length.
The cast of the interior of the phragmacone is marked by nearly
obsolete vertical ribs, extending upward along the lower half
of the living chamber, but becoming very indistinct there.

Remarks. — Amphicyrtoceras laterale evidently is closely re-
lated to- Amphicyrtoceras orcas, and there is a possibility of their
being specifically identical. At present, the vertical ribbing of

AMERICAN PALEOZOIC CEPHALOPODS

259

the casts of the interior of Amphicytoceras laterals, and a dif-
ference in the vertical outline of the upper part of the ventral
side of the living chamber, appear characteristic.

48. AMPHICYRTOCERAS TANTALUM SP. NOV.

PLATE XXIX, FIGS. 2 A, B, C

Conch small, with its maximum lateral diameter, 27.5 mm.,
along the second camera beneath the living chamber. Above
this point the lateral diameter shortens, at first slowly and then
more rapidly for a height of 15 mm., where its lateral diameter
is 19 mm. Above this the conch rises at least 8 mm. as a narrow
neck, terminating in the specimen at hand at about the level of
the aperture. The rate of enlargement of the lower part of the
phragmacone is rapid. The conch is strongly depressed dorso-
ventrally, the ratio of the dorso-ventral to the lateral diameter
being as 24 to 27.5 mm. at the widest part of the conch. At the
aperture the corresponding ratio is as 15.5 to 19 mm. At the
base of the specimen it is as 14 to 16 mm. A little over 8 camerae
occur in a length equal to the maximum width of the conch. The
sutures are nearly directly transverse, but sag down a little on
the ventral side of the conch. The septa are very moderately
concave, and the siphuncle appears to occur one-third of the
dorso-ventral diameter from the ventral side. Its passage
through the septum at the base of the specimen is small, and
the form and structure of its segments are unknown.

Locality and horizon. — From the strata regarded as approx-
imately equivalent to the Cedarville dolomite, at the abandoned
railroad quarry in the northeastern part of Hillsboro, Ohio.
Found by Henry Pavey.

Remarks. — Amphicyrtoceras tantalum is characterized by its
small size, the rapid constriction of the living chamber, and the
elongation of the upper part of this chamber into a neck.

MONOCYRTOCERAS GEN. NOV.

Genotype: Monocyrtoceras lentidilatatum Foerste

Conch related to Amphicyrtoceras, but enlarging at a much
smaller rate; there is no dorsal gibbosity; and the siphuncle is
much nearer the center of the conch, being only a short distance
ventrad of the latter.

260

AUG. F. FOERSTE

49. MONOCYRTOCERAS LENTIDILATATUM SP. NOV.

PLATE XXXVII, FIG. 1; PLATE XXXVIII, FIG. 1; PLATE XXXIX,
FIG. 1; PLATE XL, FIGS. lA, B; PLATE XLI, FIGS. 3A, B

Greenfield specimen. — Specimen consisting of the lower part
of a living chamber with 11 camerae still attached. A twelfth
camera is represented by the cast of the interior of one of the
segments of the siphuncle, at the base of the specimen. Conch
distinctly curved lengthwise, the radius of curvature of the con-
vex or ventral side being about 450 mm., and that of the concave
or dorsal side about the same. The conch is distinctly compressed
dorso-ventrally. The dorso-ventral diameter at the base of the
living chamber is 66 mm., the lateral diameter being estimated ,
at 75 mm. The lateral diameter enlarges from 60 mni. at the
base of the specimen to 75 mm. at the base of the living chamber,
the intervening distance being 125 mm., measured along the
ventral side of the conch, but most of this enlargement takes
place along the lower 5 camerae retained by the specimen. The
living chamber contracts slightly laterally, in an upward direc-
tion. The dorso-ventral diameter increases from 53 mm. at the
base to 60 mm., 5 camerae farther up, and to 66 mm. at the base
of the living chamber. Apparently it continues to enlarge for
40 mm. above the suture outlining the base of the living chamber.
About 6 camerae occur at the top of the phragmacone in a length
equal to the lateral diameter of the conch, but the uppermost
two camerae shorten rapidly, indicating that the specimen was
fully mature. In descending order, the uppermost camera has
a length of 6 mm., the next beneath of 8 mm., and the next 7 or 8
camerae of 10 or 11 mm.

The sutures of the septa curve downward moderately both dor-
sally and ventrally, and rise laterally to a corresponding degree.
The concavity of the septum at the base of the specimen equals
13 mm. When the dorso-ventral diameter is 53 mm., the center
of the siphuncle is 21 mm., or two-fifths of the dorso-ventral
diameter, from the ventral wall of the conch. The lateral diam-
eter of the siphuncle, where in contact with the septum beneath,
is 13 mm., and it contracts here suddenly to 7 mm. at the be-
ginning of the septal neck. The lower margin of this neck
flares out strongly, the length of the neck being slightly over
1 mm. The sides of the segments of the siphuncle, within the
walls of the camerae, present straight profiles, the segments hav-

AMERICAN PALEOZOIC CEPHALOPODS

261

ing the form of tubes connected by short central passages of
much smaller diameter. In form, the siphuncle closely resembles
that of Amphicyrtoceras orcas (Hall), from the Racine of Wis-
consin, but the conch is much more elongate.

The surface of the shell is crossed by transverse, and rather
faint, raised lines or striae. The surface, of the cast of the in-
terior of the specimen is faintly ribbed vertically, as in some
specimens of Amphicyrtoceras orcas.

Locality and horizon. — Greenfield, Wisconsin; in the Racine
member of the Niagaran. No. 2315, in the Museum of Compara-
tive Zoology, at Harvard University.

Living chambers from Wamvatosa. — With the specimen de-
scribed above, consisting chiefly of the phragmacone, are cor-
related two living chambers, found at another locality. These
living chambers agree fairly well in size and cross-section with
the remnant of the living chamber preserved in the preceding
specimen. Moreover, these living chambers are of such length,
and have such a slow rate of contraction toward the aperture as
to suggest that they belong to a slowly enlarging species, and
Amphicyrtoceras lentidilatatum is such a species.

At the base of one of the living chambers, the dorso-ventral
diameter is 70 mm., and the lateral diameter is 78 mm. Along
the dorsal side of the living chamber, the margin of the aperture
rises 78 mm. above the suture at its base. Here the lateral diam-
eter is 69 mm., and the dorso-ventral diameter is estimated at
63 mm. Distinct contraction of the living chamber begins about
30 to 35 mm. above its base. At the base of the cast of the in-
terior, there is a transverse groove 6 mm. high, locating the
annular attachment ring following the inner wall of the chamber.
This groove is crossed by 10 low vertical ribs in a width of
35 mm., their upward continuations being faintly visible for
some distance above the transverse groove. Laterally this
groove makes an angle of 10° with a horizontal plane, sloping
from the dorsal side downward toward the ventral. The margin
of the aperture forms a broad shallow lobe on the ventral side ;
it rises laterally and ventro-latdrally, and curves distinctly,
though only moderately, downward along the median part of
the ventral side, thus locating the hyponomic sinus. Toward
the upper part of the living chamber, the median part of the
ventral side extends slightly outward beyond the general trans-

262

AUG. F. FOERSTE

verse curvature of the conch, but so slight is this outward curva-
ture that it is likely to escape attention. An accentuation of this
outward curvature would lead to forms such as those included
under Streptoceras. ‘Within 5 or 10 mm. from the aperture the
dorsal and ventral walls of the cast of the interior of the living
chamber curve slightly outward. The surface of the shell is
striated faintly in a transverse direction, and weathered parts
of the surface show very faint vertical striae.

Location and horizon. — Schoonmaker’s quarry, at Wauwatosa,
Wisconsin, in the Racine member of the Niagaran. No. 2312, in
the Museum of Comparative Zoology, at Harvard University.

Flattened Wauwatosa phragmacone. — The specimen consists
of 15 camerae, no part of the living chamber being retained. It
is of interest chiefly because it gives some idea of the rate of in-
crease in the size of the conch, notwithstanding the fact that it is
strongly compressed dorso-ventrally, evidently during fossiliza-
tion. This flattening probably is due to vertical compression of
the enclosing strata. There is no evidence that the width of the
specimen was increased by this flattening. The height of the
camerae agrees very well with that of the camerae in the type
specimen from Greenfield, Wisconsin.

Specimen No. 2301, in the Museum of Comparative Zoology,
at Harvard University. From Wauwatosa, Wisconsin.

50. DIESTOCERAS GEN. NOV.

Genotype: Gomphoceras indianense Miller and Faber

Conch relatively erect, practically without any lengthwise cur-
vature, though possibly gently curved in its initial stages of
growth. There is only a slight difference in the lengthwise cur-
vature of the dorsal and ventral sides of the upper part of the
conch. The siphuncle is located close to the ventral wall, and
the segments are so low and broad as to appear nummuloidal.
The walls of the living chamber converge toward the aperture,
but the latter is much less contracted than in Gomphoceras. On
the contrary, the aperture remains relatively wide open, with
only a moderate angularity on the ventral side, along the hypo-
nomic sinus. The hyponomic sinus is relatively shallow and does
not form a lobe distinct from the remainder of the aperture.

Gomphoceras indianense Miller and Faber is selected as the
genotype, because this species is by far the most abundant, at

AMERICAN PALEOZOIC CEPHALOPODS

263

least in southwestern Ohio. Gomphoceras eos and Gomphoceras
obesum are congeneric. Poterioceras apertum Whiteaves, P.
nobile Whiteaves, and possibly P. gracile Whiteaves, also belong
here. Oncoceras alceus Hall is another species.

51. DIESTOCERAS INDIANENSE (MILLER AND FABER)

PLATE XXV, PIGS. lA, B; PLATE XXVI, FIGS. lA, B, 2A, B;

PLATE XXVII, FIG. 2

Gomphoceras indianense Miller and Faber, Jour. Cincinnati Soc.

Nat. Hist., vol. 17, 1894, p. 137, pi. 7, figs. 3-5

Type. — Three specimens were collected by Faber in the upper
part of the Richmond at Versailles, Indiana, and one was figured.
The siphuncle was described as marginal, located on the ventral
side of the conch, and abruptly expanded within the camerae
to two and a half or three times its diameter at the septa.

Oxford specimens. — Conch (Plate XXV, Figs. lA, B) rela-
tively short, rapidly expanding along the lower part of the phrag-
macone, attaining its largest diameter at the base of the living
chamber, distinctly contracting toward the aperture. In speci-
mens retaining about 10 of the upper camerae of the phragma-
cone, the total length of these camerae along the dorsal side of
the conch is a little greater than their total length along the ven-
tral side, and the sutures of the septa rise slightly higher along
the dorsal side, especially toward the living chamber. The ver-
tical axis of the conch is nearly straight, but there is a faint ten-
dency toward a lengthwise concave curvature along the ventral
side. From this it is assumed that the location of the siphuncle
is endogastric. The conch is slightly compressed laterally. In
the specimen which seems least flattened by lateral pressure, the
dorso-ventral diameter at the base of the living chamber is
63 mm., and the lateral diameter is 58 mm. At the base of the
specimen, 46 mm. farther down, the cross-section is virtually cir-
cular, and about 34 mm. in diameter. Two very short camerae
at the top of the phragmacone indicate that this specimen had
reached full maturity. The living chamber is 38 mm. in height.
The margin of the aperture is nearly directly transverse on its
dorsal and lateral sides, but curves distinctly downward ven-
trally, forming a relatively shallow V-shaped hyponomic sinus.
Possibly the margin of this aperture inclines slightly downward
toward the dorsal side also, but this cannot be determined def-
initely from the specimen at hand. The lateral diameter of the

264

AUG. F. FOERSTE

aperture is 39 mm.; its dorso- ventral diameter may be slightly
greater. Its general form is circular, but along its ventral mar-
gin it is distinctly angular, though the angularity still is rounded.
The margin of the aperture curves more or less horizontally in-
ward for a distance of 3 or 4 mm. ; perhaps less toward the ven-
tral angularity. At this angularity the margin of the aperture
curves downward, forming the hyponomic sinus.

In a second specimen, (Plate XXVI, Figs. lA, B) from the
same locality and horizon, the specimen is more compressed lat-
erally, probably by pressure during fossilization. The length-
wise ventral outline is more convex. The aperture is well ex-
posed, including the hyponomic sinus, but it also is compressed
laterally.

The surface of casts of the interior of the conch usually is
faintly ribbed vertically along the phragmacone. The surface of
the shell is crossed transversely by low broad lines of elevation
of variable strength, representing successive stages of growth.
These serve to locate the ventral side of the conch, where they
curve distinctly downward.

At the base of the eighth camera below the living chamber of
one specimen, where in the present flattened condition of the
specimen the diameters at right angles to each other are 42 and
37 mm., the maximum diameter of the siphuncle is 8.5 mm. and
its passage through the septum is 5.5 mm. in diameter. At its
contact with the overlying septum, the exposed segment of the
siphuncle is in contact with the latter over its entire width,
forming a circular area of contact, which is penetrated by the
passage of the siphuncle through the septum in a strongly excen-
tric position, its ventral margin being less than 1 mm. from the
ventral margin of the segment. The ventral side of the segment
is curved obliquely, in a direction approximately parallel to the
ventral wall of the conch.

Locality and horizon. — Little Four Mile creek, near Oxford,
Ohio ; in the lower part of the Whitewater member of the Rich-
mond formation. In the collection of Prof. W. H. Shideler, at
Miami University.

Faber specimen. — A vertical section, in a dorso-yentral direc-
tion, through a specimen (Plate XXVI, Figs. 2 A, B) collected
by Mr. C. L. Faber at the same horizon on Little Four Mile
creek, exposes the siphuncle sufficiently to indicate its relative

AMERICAN PALEOZOIC CEPHALOPODS " 265

size, and the convexity of the vertical outlines of its segments ;
but the siphuncle has broken loose from the septa, and the struc-
ture of the siphuncle can not be determined in a satisfactory
manner.

Saluda and Elkhorn specimens. — Specimens from the Saluda
and Elkhorn members of the Richmond are in the collection of
Prof. W. H. Shideler. These specimens evidently are congeneric
with Diestoceras indianense , but not enough of the conch is pre-
served to make certain that they belong to the same species. One
of these Salula specimens (Plate XXVII, Fig. 2) preserves the
surface striae very well.

52. DIESTOCERAS EOS (HALL AND V^HITFIELD)

PLATE XXVIII, FIGS. lA, B

Gomphoceras eos Hall and Whitfield: Geol. Surv. Ohio, Pal., vol. 2,
1875, p. 100, pi.' 3, fig. 5

'‘Type. — Specimen 112 mm. in length; of this length 65 mm.
belongs to the living chamber, 36 mm. belong to that part of the
phragmacone which occurs between the base of the living
chamber and the suture of the septum at the base of the speci-
men, and 11 mm. belongs to that part of the specimen which
extends below the level of this suture in consequence of the down-
ward curvature of the septum.

In its present condition the specimen is very much crushed
laterally. The maximum expansion of the conch takes place
about 23 mm. above the base of the living chamber. Here the
dorso-ventral diameter is 81 mm., and the lateral diameter is
36 mm. At the base of the living chamber the corresponding
diameters are 74 and 30 mm. At the base of the specimen these
diameters are 44 mm. and 19 mm. The apical angle of that part
of the phragmacone which is preserved approximates 45°. Above
mid-height of the living chamber the latter contracts so that
at 55 mm. above its base the dorso-ventral diameter is 62 mm.
and the lateral diameter 21 mm. Above this level the living
chamber continues to contract until its dorso-ventral diameter
does not exceed 55 mm.

It is assumed, from the better preserved specimens of Diesto-
ceras indianense, that the cross-section of Diestoceras eos orig-
inally was nearly circular, and that the outline of the aperture
was nearly circular, with a moderate amount of angularity along
the ventral margin. In conformity with other species referred

266

AUG. F. FOERSTE

to Diestoceras, the side along which the septa are more approxi-
mate is regarded as ventral, while that along which they are
more distant from each other is regarded as dorsal. Along the
ventral side of the specimen 7 camerae occupy a length of
36 mm., while along the dorsal side the same 7 camerae occupy
a length of 46 mm. The sutures of the septa rise slightly from
the ventral toward the dorsal side of the conch. They are ap-
proximately straight. The septa may have been more deeply
concave than in Diestoceras indianense, but the exposed septum
at the base of the specimen may have secured its present form
from crushing. No trace of the siphuncle is retained.

Locality and horizon. — From the vicinity of Dayton, Ohio, at
the base of the Whitewater member of the Richmond formation.
Specimen No. 3082, in the Geological Museum of Ohio State Uni-
versity. Along its upper margin the specimen contains a ventral
valve of Rhynchotrema cayax. Traces of an incrusting bryozoan
occur on one side of the specimen.

Remarks. — Diestoceras eos differs from typical Diestoceras
indianense in attaining the maximum enlargement of the conch
at a point distinctly above the base of the living chamber. It is
possible that the two species are identical, but, without a greater
number of specimens at hand, it is not known within what limits
Diestoceras indianense varies. The type of Diestoceras eos is so
badly flattened as to leave elements of uncertainty, while that of
Diestoceras indianense is much less distorted, and this species
can be identified with confidence. For the present, at least, the
latter is described as distinct.

53. DIESTOCERAS SHIDELERI SP. NOV.

PLATE XXVII, FIGS. lA, B

Specimen presenting an elongate elliptical outline, consisting
chiefly of a living chamber 55 to 58 mm. in height, with 4 cam-
erae attached at its base. The specimen reaches its greatest
transverse dimensions at mid-height of the living chamber. Here
its lateral diameter is 67 mm., and its dorso-ventral diameter is
63.5 mm. At the base of the living chamber' the corresponding
diameters are 64 and 61 mm. respectively. At 50 mm. above the
base of the living chamber the lateral walls curve strongly in-
ward and then upward. Possibly this change in curvature indi-
cates merely a thickened border in the interior of the chamber,

AMERICAN PALEOZOIC CEPHALOPODS

267

strengthening the margin of the aperture. Along the ventral
side this margin appears to curve down\vard, forming a distinct
hyponomic sinus.

The upper part of the phragmacone narrows so rapidly in an
apicad direction that it is probable that the phragmacone was
very short. The sutures of the septa rise distinctly from the
ventral toward the dorsal side of the conch, and the height of
the camerae enlarges in this direction. The siphuncle is exposed
close to the ventral side of the conch. Within the lowest camera
its diameter was at least 14 mm. The location of the passage of
the siphuncle through the septum evidently was similar to that
in Diestoceras indianense.

54. CYRTOGOMPHOCERAS GEN. NOV.

Genotype: Oncoceras magnum Whiteaves. Trans. Royal Soc.

Canada, vol. 7, sec. 4, 1890, p. 79, pi. 15, fig. 1

Conch distinctly curved lengthwise, endogastric, and laterally
compressed. The dorsal side is strongly convex, and the ven-
tral outline of all but the uppermost part of the phragmacone is
slightly concave, but along the top of the phragmacone and the
adjacent part of the living chamber the ventral outline is dis-
tinctly gibbous. Conch compressed laterally. Sutures of the
septa rising strongly from the ventral toward the dorsal side of
the conch along the upper part of the phragmacone. Aperture
correspondingly oblique, the living chamber being strongly con-
tracted toward the latter. Siphuncle near the ventral wall of
the conch, its segments strongly nummuloidal.

In addition to the genotype, Oncoceras magnum Whiteaves,
this genus includes also Oncoceras ivhiteavesii Miller, a species
originally described by Whiteaves as Oncoceras gibbosum.

Oncoceras intermedium Whiteaves is similar in having a
strongly nummuloidal siphuncle near the concave or ventral side
of the conch, and in having the septa rise strongly toward the
dorsal side, but the conch is more slender, there is nO' gibbosity
along the ventral side of the conch, and there is no evidence at
present of the living chamber having a structure similar to that
of typical Cijrtogomphoceras,

PLATE XXI

Fig. 1. Endoceras proteiforme Hall. Ventral side of the conch, show-
ing downward flexure of the sutures of the septa, the siphuncle, and traces
of the endocones, both at the top and near the middle of the specimen.
Same specimen as fig. 4 on pi. 48 of Pal. New York, vol. 1, 1847. See also
plate XXII, figs. lA, IB. Selected here as type of the species.

Fig. 2. Endoceras proteiforme Hall. Ventral side of a specimen, show-
ing the downward curvature of the sutures of the septa, and the concave
vertical outline of the septal necks of the siphuncle. Same specimen as
fig. la on plate 49 of Pal. New York, vol. 1, 1847. See also fig 2 on pi.
XXII, and fig. 2 on pi. XXIII.

Fig. 3. Endoceras proteiforme Hall. Ventral side of a specimen, show-
ing the siphuncle. Same specimen as figs, lb, Ic on pi. 49 of Pal. New York,
vol. 1, 1847. See also figs. lA, IB on pi. XXIII.

All specimens figured on this plate are from Middleville, New York, in
the Trenton limestone.

Journal Scientific Laboratories Denison University Vol. XX

PLATE XXI

AUG. F. FOERSTE

AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXII

Fig. 1. Eyidoceras proteiforme Hall. A, three transverse sections* of the
type specimen at intervals corresponding to the distances between the
centers of the sections; showing the rate of increase of the conch, siphuncle,
and endocones. B, diagrammatic ventro-dorsal vertical section of the same
specimen. See also fig. 1 on pi. XXL

Fig. 2. Endoceras proteiforme Hall. Transverse section of same speci-
men as fig. 2 on pi. XXI, with missing parts indicated by broken lines.
See also fig. 2 on pi. XXIII.

Fig. 3. Endoceras proteiforme Hall. Transverse section of same speci-
men as fig. 2 on pi. XXV, with missing parts indicated by broken lines.
See also fig. 3 on pi. XXIII.

All specimens figured on this plate are from Middleville New York, in the
Trenton limestone.

AUG. F. FOERSTE

AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXIII

Fig. 1. Endoceras proteiforme Hall. A, vertical section, showing the
upper part of an endocone. B, cross-section showing siphuncle and endocone.
Same specimen as fig. 3 on pi. XXI.

Fig. 2. Endoceras proteiforme Hall. Vertical section through the siph-
uncle, showing the apical part of an endocone. Same specimen as fig. 2
on pi. XXI, and fig. 2 on pi. XXII.

Fig. 3. Endoceras proteiforme Hall. Vertical section of the endocone
in fig. le of pi. 49 of the Pal. of New York, vol. 1, 1847, to show its rate
of taper and its form before it was distorted. See also fig. 2, on pi. XXV,
and fig. 3 on pi. XXII.

All specimens figured on this plate are from Middleville, New York, in the
Trenton limestone.

Journal Scientific Labora'iories Denison Univeusity Vol. XX

PLATE XXIII

AUG. F. FOERSTE

AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXIV

Figs. 1-5, Cameroceras trentonense Hall. 1, 2A, lateral views showing
siphuncle. 2B, ventral view of 2A. 3, cast of interior of siphuncle and

endocone; compare with 5. 4, lateral view, exposing one segment of the

siphuncle. 5, endocone, thickened interiorly by a calcareous deposit, lighter
in color, contrasting with the darker color of the matrix filling the interior
of the endocone. 1, 2, from Middleville, New York; No. 815 in American
Museum of Natural History; originals of Pal. New York, vol. 1, 1847, pi.
56, figs. 4 a, b, c. 3, 4, from Multona brook, 2 miles northeast of Middle-
ville, New York; No. 59449, in the U. S. National Museum. 5, from Poland,
in Herkimer, New York; No. 59450, in the U. S. National Museum. All
specimens from the Trenton limestone.

Figs. 6 A-E'. Cameroceras calumettense Foerste. A lateral view; B, view
of same specimen, facing the interior of the conch. C, ventral side of an-
other specimen. D, E, opposite sides of an endocone split so as to show the
thicknened inner walls of the endocone, but omitting the deposit of matrix
which filled its interior. At the base of the specimen, the axial part of the
calcareous deposit is occupied by a thin transverse band, scarcely 1 mm. in
width. From Little Calumet creek, 6 miles south of Louisiana, Missouri.
In the U, S. National Museum.

Journal Scientific Laboratories Denison University Vol. XX PLATE XXTV

AUG. F. FOERSTE

AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXV

Figs. 1 A, B. Diestoceras indianense (Miller and Faber). A, ventral
view. B, lateral view of same specimen. From Little Four Mile creek,
near Oxford, Ohio; in the lower part of the Whitewater member of the
Richmond. Collected by Prof. W. H. Shideler of Miami University.

Fig. 2. Endoceras proteifoy'me Hall. Lateral view, with ventral side on
left. See also Plate XXII, Fig. 3; Plate XXIII, Fig. 3. From Middleville,
New York. Same specimen as Fig. le on PI. 49, of the Pal. New York,
vol. 1, 1847. In the Trenton limestone.

Fig. 3. Orthoceras breynii Martin. Ventral side. Figure copied from
Petrefacta Derbiensis, 1809, pi. 39, fig. 4. Stated to be frequent in black
marble at Ashford. A Carboniferous species.

Fig. 4. Orthoceras annularis Fleming. Lateral view, inverted from
original. Copied from Fleming, Ann. Phil., pi. 31, Fig. 8. Carboniferous.

Fig. 5. Orthoceras annulare Phillips. Lateral view. Copied from Phil-
lips, Geology of Yorkshire, 1836, pi. 21, fig. 9. Carboniferous.

Journal Scientific Laboratories Denison University Vol. XX

PLATE XXV

AUG. F. FOERSTE

AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXVI

Figs. 1 A, B. Diestoceras indianense (Miller and Faber). A, lateral
view. B, ventral view. From Little Four Mile creek, near Oxford, Ohio.
Collected by Prof. W. H. Shideler, of Miami University.

Figs. 2 A, B. Diestoceras indianense (Miller and Faber). A, vertical
dorso-ventral section showing poorly preserved siphuncle. B, same speci-
men. From Little Four Mile creek, near Oxford, Ohio. Collected recently
by C. L. Faber, from the basal part of the Whitewater member of the
Richmond formation.

Journal Scientific Laboratories Denison University Vol. XX

PLATE XXVI

AUG, F. FOERSTE

AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXVII

Figs. 1 A, B. Diestoceras shideleri Foerste. A, lateral view with ven-
tral side on right. B, ventral view, with siphuncle at base. From the
basal part of the Whitewater member of the Richmond. Collected by Prof.
W. H. Shideler, of Miami University.

Fig. 2. Diestoceras cf. indianense (Miller and Faber). View showing
the surface striae. From the Saluda member of the Richmond. Collected
by Prof. W. H. Shideler.

Figs. 3 A, B. Perigraminoceras laevigatum (McCoy). A, partly ex-
foliated conch, with surface of shell showing transverse striae. B, part
of specimen enlarged, showing surface striae. Copied from Foord, Carb.
Ceph. Ireland, 1897, pi. 5, figs. Id, le. Of Carboniferous age.

Journal Scientific Laboratories Denison University Vol. XX

PLATE XXVII

AUG. F. FOEKSTE

AMERICAN PALEOZOIC CEPTIALOPODS

PLATE XXVIII

Fig’S. 1 A, B. Diestcceras eos (Hall and Whitfield). Opposite sides of
the same specimen. Ventral side assumed to be near left side of A, and
right side of B. From vicinity of Dayton, Ohio, assumed to be from basal
part of Whitewater member of Richmond. Type, numbered 3082, in the
Geological Museum of Ohio State University. Same specimen as that
figured in Ohio Pal., 2, 1875, pi. 3, fig. 5.

Figs. 2 A, B. Loxoceras distans McCoy. A, lateral view with ventral
side on right. B, cross-section, with lateral diameter larger. Copied from
McCoy, Carb. Foss. Ireland, 1844, pi. 4, fig. 1. From the Carboniferous.

Fig. 3. Lituites sp. Vertical section through a fragment, from a large
series of specimens from Esthonia, in the U. S. National Museum.

Journal Scientific Laboratories Denison University Vol. XX

PLATE XXVIII

AUG. F. FOERSTE

AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXIX

Figs. 1 A, B, C. Amx>liicyrtoceras orcas (Hall). A, ventral view. B,
lateral view showing the septa. C, two cross-sections, one taken at the
base of the living chamber, the other 5 camerae lower. From Waukesha,
Wisconsin; in the Racine member of the Niagaran. Type, numbered 2112,
in the American Museum of Natural History. Same specimen as in 20th
Rep. New York State Mus. Nat. Hist., 1868, pi. 17, figs. 1, 2.

Figs. 2 A, B, C. Amphicyrtoceras tantalum Foerste. A, ventral view.
B, lateral view. C, two cross-sections, one at base of living chamber, the
other at base of specimen. From railroad quarry in northeastern edge
of Hillsboro, Ohio; from the Cedarville member of the Niagaran.

Journal Scientific Laboratories Denison University Vol. XX

AUG. F. FOERSTE

AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXX

Figs. 1 A, B, C, D. Amphicyrtoceras laterale (Hall). A, dorsal view.
B, lateral view. C, cross-section at base of the living chamber. D, vertical
dorso-ventral section, exposing the siphuncle, taken at top of phragmacone.
From Racine member of Niagaran at some Wisconsin locality. No. 634, in
the Public Museum of Wilwaukee, Wisconsin.

Figs. 2 A, B. Amphicyrtoceras laterale (Hall). A, ventral view. B,
two cross-sections, one at base of living chamber, the other at base of
specimen. From Racine, Wisconsin, in the Racine member of the Niagaran.
Type, numbered 2119, in the American Museum of Natural History. Same
specimen as that figured in 20th Rep. New York State Museum Nat. Hist.,
1868, pi. 18, figs. 4, 5, 6.

Journal Scientific Laboratories Denison University Vol. XX

PLATE XXX

AUG. F. FOERSTE AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXXI

Fig. 1. Charactoceras baeri (Meek and Worthen). Lateral view. See
also plate XXXII, figs, lA, B. From vicinity of Oxford, Ohio, in the basal
part of the Whitewater member of the Richmond. Collected by Prof. W. H.
Shideler, of Miami University.

Figs. 2 A, B, C, D. Tripteroceras hastatum (Billings). A, ventral side,
exposing the siphuncle. B, view of upper end, showing passage of siphuncle
through septum. C, diagrammatic lateral view, showing the lateral saddles.
D, diagram showing relative depth of dorsal and ventral lobes of the
sutures. From Pauquette Rapids, in Ottawa River, Canada, in the Leray
member of the Black River. Selected type, numbered 1281, in the Victoria
Memorial Museum at Ottawa, Canada.

Figs. 3 A, B, C, D. Tripteroceras pauqiiettense Foerste. A, lateral view.
B, ventral view. C, diagram showing relative depth of dorsal and ventral
lobes of sutures. D, cross-section at top of specimen, showing passage of
siphuncle through septum. Part of the type series of Tripteroceras hasta-
tum (Billings), numbered 1281 d, in the Victoria Memorial Museum, at
Ottawa, Canada. Selected here as type of new species.

PLATE XXXI

foURNAr, ScXENTrFIC r.ABORATORlES DeNTSON UNIVERSITY VoL. XX

rSi- ;

AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXXII

Figs. 1 A, B. Charactoceras baeri (Meek and Worthen). A, ventral
view including top of phragmacone and base of living chamber. B, ventral
view of living chamber, showing hyponomic sinus. Same specimen as
Plate XXXI, Fig. 1.

Journal Scientific Laboratories Denison University Vol. XX

PLATE XXXII

AUG. F. FOERSTE

AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXXIII

Figs. 1 A, B. Charactoceras baeri (Meek and Worthen). A, lateral
view. B, ventral view, including upper part of phragmacone and basal
part of living chamber. From vicinity of Oxford, Ohio, in the basal part of
the Whitewater member of the Richmond. Collected by Prof. W. H. Shid-
eler, of Miami University.

Journal Scientific Laboratories Denison University Vol. XX

PLATE XXXIII

AUG. F. FOERSTE

AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXXIV

Fig. 1 A, B. Charactoceras haeri (Meek and Worthen). A, ventral
vie’w of an incomplete specimen, showing the surface striae. B, lateral view
of the same specimen. From the vicinity of Oxford, Ohio, in the basal part
of the Whitewater member of the Richmond. Collected by Prof. W. H.
Shideler, of Miami University.

Fig. 2. Charactoceras haeri (Meek and Worthen). Dorso-ventral
section, exposing the siphuncle. From Flat Fork, 4 miles northeast of
Oregonia, Ohio, in the basal part of the Whitewater member of the Rich-
mond. Collected by Prof. J. E. Carman, of Ohio State University.

PLATE XXXIV

Journal Scientific Laboratories Denison L'niversity Vol. XX

AUG. F. FOERSTE

AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXXV

Figs. 1 A, B. Elrodoceras indianense (Miller). A, B, lateral views of
opposite sides of the same specimen, A showing the sutures of the septa, and
B showing the surface striae. From some Indiana locality, in the upper
part of the Laurel member of the Niagaran. Specimen No. 2133 in the
Museum of Comparative Zoology, at Harvard University. Second type of
Rhynchorthoceras dubium Hyatt. See also Plate XXXVI, Figs. lA, B.

Figs. 2 A, B, C. Billingsites (?) ivilliamsportense Foerste. A, lateral
view. B, more convex side, assumed to be ventral. C, less convex side,
assumed to be dorsal. From Williamsport, Tennessee. Specimen No.
483D5, in the U. S. National Museum.

PLATE XXXV

JouR'NAL Scientific Laboratories Denison University Vol. XX,

AUG. F. FOERSTE

AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXXVI

Figs. 1 A, B. Elrodoceras indianense (Miller). A, ventral view showing
the surface striae. B, opposite side of same specimen, showing the camerae,
and the top of the siphuncle. From some locality in Indiana, in the upper
part of the Laurel member of the Niagaran. Chief type of Rhynchor-
oceras duhium Hyatt, numbered No. 2132, in the Museum of Comparative
Zoology, at Harvard University.

Figs. 2 A, B. Beloitoceras lycum (Hall). A, lateral view, cast of in-
terior. B, ventral view. From Beloit, Wisconsin, in the Beloit member of
the Black River. No. 999, in the American Museum of Natural History.
Same specimen as Amer. Mus. Nat. Hist., Bull. 1, pt. 2, 1895, pL 9, figs. 13,
14. See also Plate XLI, figs. 6 A, B, in this Journal.

Figs. 3 A, B. Beloitoceras plebeium (Hall). A, lateral view, cast of in-
terior. B, ventral view. From Beloit, Wisconsin, in the Beloit member of
the Black River. Specimen numbered 996, in the American Museum of
Natural History. Same specimen as that figured by Whitfield, in Bull.
Amer. Mus. Nat. Hist., 1, pt. 2, 1895, pi. 9, figs. 18, 19.

Figs. 4 A, B. Beloitoceras plebeium (Hall). A, lateral view, cast of in-
terior. B, ventral view. From Beloit, Wisconsin, in the Beloit member of
the Black River. Specimen numbered 996, in the American Museum of
Natural History. Same specimen as that figured by Whitfield, in Bull.
Amer. Mus. Nat. Hist. 1, pt. 2, 1895, pi. 9, figs. 15, 16. See also Plate XLI,
figs. 5 A, B.

Figs. 5 A, B. Beloitoceras pandion (Hall). A, lateral view, cast of in-
terior. B, ventral view. From Beloit, Wisconsin, in the Beloit member of
the Black River. Specimen numbered 998, in the American Museum of
Natural History. Same specimen as that figured by Whitfield, Bull. Amer.
Mus. Nat. Hist., 1, No. 2, pi. 9, figs. 21, 22. See also Plate XLI, figs. 4A,
B, C.

The lines over figures 3A and 4A indicate the probable outline of the
aperture on lateral view.

Journal Scientific Laboratories Denison University Vol. XX

PLATE XXXVI

AUG. F. FOERSTE AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXXVII

Fig’. 1. Monocyrtoceras lentidilatatum Foerste. Lateral view, ex-
posing one segment of the siphuncle at the base. See also Plates XXXVIII,
fig. 1; XXXIX, fig. 1; XL, figs. 1 A, B ; and XLI, figs. 3 A, B. From Green-
field, Wisconsin, in the Racine member of the Niagaran, Specimen No. 2315
in the Museum of Comparative Zoology, at Harvard University.

Fig. 2. Elrodoceras indianense (Miller). Ventral side, retaining the
transverse surface striae. From Hartsville, Indiana, in the Laurel mem-
ber of the Niagaran. Same specimen as that figured by Miller, in 17th Ann.
Rep. Dep. Geol. Nat. Res. Indiana, 1892, pi. 18, fig. 2.

Fig. 3. Elrodoceras cf. mdianense (Miller). Natural section, exposing
the siphuncle. From Lemont, Illinois, in the Niagaran. Specimen No.
22917, in the Museum of Comparative Zoology, at Harvard University.
See also Plate XXXVHI, fig. 2.

Journal Scientific Laboratories Denison University Vol. XX

DLATJi XXXVII

AUG. F.

AMJvl^ICAX PALEOZOIC CEPHAI.OPODS

FOERSTK

PLATE XXXVIII

Fig. 1. Monocyrtoceras lentidilatatiim Foerste. Ventral view, ex-
posing one segment of the siphuncle at the base. Same specimen as Plate
XXXVII, fig. 1.

Fig, 2. Elrodoceras indianense (Miller). Lateral view, with ventral
side on right; exposing 4 segments of the siphuncle. Same specimen as
Plate XXXVII, fig. 2.

Fig. 3. Elrodoceras cf, indianense (Miller). Lateral view of part of
cast of interior of siphuncle, showing relative size of passage of siphuncle
through septum at top of specimen. From Joliet, Illinois, in the Niagaran.
No. 22916, in Walker Museum, at University of Chicago.

Fig, 4. Actinoceras sp. Lateral view of cast of interior of siphuncle,
showing nature of deposits here. From Joliet, Illinois, in the Niagaran.
Also numbered 22916, in Walker Museum, but belonging to a different
species from the preceding.

Journal Scientific Laboratories Denison University Vol. XX

PLATE XXXVIII

AUG, F. FOERSTE

AMERICAN PALEOZOIC CEPHALOPODS

PLATE XXXIX

Fig'. 1. Monocyrtoceras lentidilatatum Foerste. Dorsal view, in-
verted in order to illuminate the side best preserved; with one segment
of the siphuncle exposed. Same specimen as Plate XXXVII, fig. 1.

Fig. 2A, B. Oncoceras constrictum Hall. A, lateral view; B, ventral
view of same specimen, showing surface striae. From Middleville, New
York, in the Trenton limestone. Same specimen as 3rd Rep. New York
State Museum, 1850, pi. 3, figs. 3 a, b.

Fig. 3. Oncoceras constrictum Hall. Lateral view, exposing base of liv-
ing chamber. From Middleville, New York, in the Trenton limestone.
Same specimen as Pal. New York, 1, 1847, pi. 41, figs. 6 a, b, c.

Fig. 4. Oyicoceras constrictum Hall. View of septum at base of another
specimen, showing passage of siphuncle through septum. From Middle-
ville, New York, in Trenton limestone. Same specimen as Pal. New York,
1, 1847, pi. 41, figs. 7 a, b, c. i

Figs. 5 A, B, C. Maelonoceras billingsi Foerste. A, lateral view, with
ventral side on left. B, view of aperture. C, ventral view. From LaCloche
Island, in northern Lake Huron, in the Black River. Specimen No. 1294,
in Victoria Memorial Museum. One of two specimens described and
figured by Billings under Phragmoceras praematurum.

Figs. 6 A, B, C. Maelonoceras praematurum (Billings). A, dorsal view.
B, lateral view with ventral side on left. C, lateral view with ventral side
on right, surface showing transverse striae. From LaCloche Island, in
northern Lake Huron. One of two specimens described and figured under
Phragmoceras praematurum. See also Plate XLI, fig. 7.

Journal Scientific I.aboratories Denison I^niversitv Vol. XX

PLATE XXXIX

AUO. V. FOERSTE

AATERICAN PALEOZOK' CEPHAEOPODS

PLATE XL

Figs. lA, B. Monocyrtoceras cf. lentidilatatiim Foerste. A, lateral
view; B, ventral view. Neither presents the outline of the aperture,
although the full height of the living chamber appears to be retained by
the specimen. From Wauwatosa, Wisconsin, in the Racine member of
the Niagaran. Specimen No. 2312, in Museum of Comparative Zoology, at
Harvard University.

Fig. 2. Poterioceras fiisiforme (Sowerby). Lateral view. Copied from
Foord, Carb. Ceph. Ireland, 1897, pi. 15, fig. 2b. From the Carboniferous.

Journal Scientific Laboratories Denison University Vol. XX

PIRATE XL

AUG. E. foerste AMERICAN PALEOZOIC CEPHALOPODS

PLATE XLI

Fig'S. 1 B. Poterioceras fusiforyne (Sowerby). Diagram, , showing
outline of conch, course of sutures along upper part of phragniacone, and
vertical section through lower part of specimen, B, siphuncle of same
specimen, enlarged. From Kildare, Ireland, in the Carboniferous. Speci-
men No. 2177, in the Museum of Comparative Zoology, at Harvard Univer-
sity.

Fig. 2. Charactoceras haeri (Meek and Worthen). Cross-section at
three points across the same phragmacone, to show the change in form with
age. Same specimen as Plate XXXIV, fig. 2.

Fig. 3 A, B. Monocyrtoceras lentidilatatum Foerste, A, cross-sec-
tion showing location of siphuncle. B, dorso-ventral section, showing gen-
eral outline of siphuncle. Same specimen as Plate XXXVII, fig, 1,

Fig. 4 A, B, C. Beloitoceras pandion (Hall). A, outline of aperture,
B, cross-section of conch. C, dorso-ventral section through siphuncle, en-
larged. Same specimen as Plate XXXVI, figs. 5 A, B, C.

Figs. 5 A, B. Beloitoceras jjlebeium (Hall). A, outline of aperture.
B, cross-section of conch, at largest diameter. Same specimen as Plate
XXXVI, figs. 4 A, B, C.

Figs. 6 A, B. Beloitoceras lycum (Hall). A, cross-section of conch at
largest diameter. B, dorso-ventral section through siphuncle. Same speci-
men as Plate XXXVI, figs. 2 A, B.

Fig. 7. Maelonoceras praematurum (Billings). Vertical dorso-ventral
section, showing fusiform segments of siphuncle. Same specimen as pi.
XXXIX, figs. 6 A, B. C.

Fig. 8. Clarkoceras merciirkis (Billings). Vertical dorso-ventral sec-
tion, with siphuncle on left side, showing concave vertical outline of seg-
ments of the siphuncle; enlarged. Diagrammatic drawing prepared from
the type specimen No. 826, in the Victoria Memorial Museum, at Ottawa,
Canada. Originally described under Cyrtocerina.

Fig. 9. Cyrtocerina typica Billings. Vertical dorso-ventral section,
with siphuncle on left side, showing convex vertical outline of segments of
the siphuncle; enlarged. Diagrammatic drawing prepared from the type
specimen, No. 1301, found at Pauquette Rapids, on Allumette Island, in
the Black River formation. In Victoria Memorial Museum, at Ottawa,
Canada.

Journal Scientific Laboratories Denison University Vol. XX

AUG. F. FOERSTE

AMERICAN PALEOZOIC CEPHALOPODS

PLATE XLII

Figs. 1 A, B. Orthoceras clarksvillense Foerste. A, cast of interior of
conch. B, natural vertical section of same specimen, showing the cyl-
indrical segments of the siphuncle. Specimen No. 48255, in the U. S.
National Museum. From the Waynesville member of the Richmond forma-
tion at Clarksville, Ohio.

PLATE XLII

Journal Scientific Laboratories Denison University Vol. XX

AUG. F. FOEKSTE

AMERICAN PALEOZOIC CEPHALOPODS

A REPORT ON THE THEORY OF RELATIVITY.

(EINSTEIN THEORY)

Paul Biefeld

During the past twenty-five to thirty years phenomenal work
has been done in the physical sciences. We need only recall
X-rays, followed by radioactivity, then electrons and wireless.
The experimental work along these lines has, however, also
brought into question some of the fundamental principles of the
science itself; leading to the abandonment, notably, of the follow-
ing three : the unchangeableness of the atom, the independence
of space and time,, and the continuity of dynamical action. The
letting go of the first led to the electron theory, of the second to
the theory of relativity, and of the third to the quantum theory.
The corner stones of the structure have, however, been in no wise
affected. The principle of the conservation of energy and that of
the conservation of mass, although the latter has been merged
into the first by the restricted theory of relativity; the laws of
thermodynamics ; the principle of least action ; all of these have
been all the more firmly established. They have stood the fire of
searching experiment of modern physics.

The Restricted Principle of Relativity

It is necessary at the outset to consider the concepts of space
and time, in particular the relation of these concepts to experi-
ence. In this connection the terms “absolute space’’ and “abso-
lute time” have no meaning. The physicist thinks of space only
in connection with the occurrence of events. In fact it is not
even the point in space ‘where’ something is, nor the instant of
time ‘when’ something happens, but the event itself, that is to
him the only physical reality.

We shall consider the distance or space interval between two
points referred to a body of reference or frame of reference ex-
pressed in Cartesian cocrdinatee.. Calling x^,Xo,Xo the coordi-
nates, the interval becomes :

s-= Ax‘J+ Ax;-k Axj: (1)

in which the Ax’s are the projections of the interval on the axes,

269

270

PAUL BIEFELD

the axes being thought of as rigid rods and the unit length a
short rigid bar.

Time is expressed by means of a body, or system, called a clock
that counts off events, the intervals between them being consid-
ered of equal length.

Time and space as above defined serve only to represent to the
physicist the complex of experiences relating to the events ob-
served by him.

To give a physical significance to the concept of time and to
establish definite relations between different points in space a
physical process of some kind must be used. As the propagation
of electromagnetic radiations or light in vacuum is the one that
has been most accurately investigated and determined, this is
chosen for the purpose ; not for the reason, however, as has been
brought forward by some of the objectors to the theory, that this
particular process is essential to the theory; any other equally
well determined process would serve as well.

There are two postulates on which the theory rests : the prin-
ciple of relativity and the constancy of the velocity of light;
stated definitely as follows :

1. The lav^s according to which the physical conditions of sys-
tems change are independent of the fact to which of two frames
of reference, having relative uniform rectilinear motions, these
changes of conditions are referred. (Relativity of uniform mo-
tions.)

2. Light has a definite and constant velocity “c’’ in a frame of
reference at rest, independent of the fact whether the source of
light is in motion or at rest.

Let a clock be placed at a point A where an observer may
'‘time’' an event in its immediate vicinity and a second similar
clock placed at a point B where a second observer may “time”
an event in a similar manner ; this does not lead, however, with-
out further consideration to the fact that the times of the events
at A and B may be directly compared. For we have up to this
time only defined a ‘time at A’ and a ‘time at B’ but not a ‘com-
mon time.’ This common time will now be defined by means of
the second postulate; stating, that it takes the same time for
light to travel from A to B, as it does to go from B to A.

We therefore send a light signal from A to B where it is re-
flected to A. Let t ^ be the time at A or the ‘A-time’ and t „ be the

A B

THEORY OF RELATIVITY

271

time at B or ‘B-time’ and t' the time of arrival of the reflected

A

ray at A. The clocks then run synchronously if t^ — a””^b
This equation defines ‘time’ and ‘symultaneity of time’. The
velocity of light is then also defined by :

2AB

(2)

We may now assume the uniform velocity of light in all di-
rections, there being no reason for assuming the direction A-B
as unique.

Assuming now A as the source of light and at the same time
the origin of a frame of reference K at rest. If r is the distance
of the point B from A; after the time At the wave front will be
the surface of sphere passing through B, for according to the
second postulate the equation holds :

Y^C.At

If we express the difference of coordinates by Axv, d from 1 to
3, and squaring we get

:S(Ax^)2_c2At2=o (3)

This equation evidently formulates the principle of the velocity
of light relative to K which must be independent of the motion
of the source A.

We now take another frame of reference K' in uniform recti-
linear motion relative to K. K and K' are then inertial systems.
With respect to K' we have the equation :

^(Axj^)“ — c^At“=^ (3a)

Equations (3) and (3a) must be mutually consistent with each
other with respect to a definite transformation, transforming K'
into K. Again an interval has a physical meaning only if it is
independent of the choice of coordinates which is true evidently
also of the spherical surfaces represented by (3) and (3a).

We will now develop the Lorentz transformation in an elemen-
tary way.

Let the Xj coordinate axis be parallel to the x\ axis and X2=x'2
also X3=x'3 of K and K' respectively. Furthermore we must have :

X“ cH=:X'2 — ct'^ . (4)

and

x'^=k(x — vt) ; x^ =k' (x' -f- vt' ) (5)

272

PAUL BIEFELD

in which k and k' are constants depending only on c, the velocity
of light ; and v, the relative velocity of K' with respect to K. We
calculate now from the second equation of (5) with the aid of
the first of (5) :

t'=k [t-

-) 3

(6)

and put the value of x', and t' from (5) and (6) into equation
(4) A comparison of the coeficients of x\, t- and x^t leads to:

k=k^

VI — —

c2.

Substituting k and k' in (5) and (6) we get:

X^ vt t — ^ x^

xh=; , t' = , and x'2=Xo , x'^^x,. (7)

VI— ^ Vl^"^

c2 C"-

Solving for x^, t, x^ and x^ we get:

x'l+vt' t'-f-^x'i

Xi — , t = and Xo = x'., , X3 = x'. (8)

Vl^'V

These equations were for the first time developed by H. A.
Lorentz hence the name '‘Lorentz transformation.’'

Let us place a number of synchronous clocks in the system K.
If their rates are zero they will remain synchronous. Some of
these clocks are now transferred to the system K' having its axes
parallel to those of K and moving relative to K with a uniform
rate parallel to the X, axis. The clocks in K' as seen by an ob-
server at rest in K, will depart from synchronism relative to the
clocks in K, losing time or going slower. Rods of definite length
as measured in K if placed in K' after they have been given the
same motion as the system K', and placed in the X\ axis will
seem contracted as viewed by the same observer at rest in K. If
the velocity of K' with reference to K is known, both the change
of rate of the clocks and the contraction of the rods may be nu-
merically accounted for by means of the Lorentz transformation
given above. It is of course evident that these changes will be

extremely small on account of the second order effect: V^ oc-
curring in the equation. If for instance v were as large as the
orbital velocity of the earth, 18.5 miles per second, the value
of the expression just given would be of the order 10.-®

THEORY OF RELATIVITY

273

It was also H. A. Lorentz who adopted the so-called contraction
theory, first suggested by Fitzgerald, to satisfy his equations in
connection with electron motion ; assuming the contraction to be
real the electrons taking on ellipsoidal form with their shorter
axes in the direction of motion; hence the term '‘Lorentz contrac-
tion/’ In this theory there would, however, be involved some
relation of this contraction to a corresponding physical change
within the electron varying with the speed of the electron of
which there is no trace. Einstein solved the enigma with one
stroke by establishing the relativity of time and space leading
to the same Lorentz equations but on a more rational basis.

Prof. Lorentz has the following to say in his Columbia lectures
already referred to: “ . . . he (Einstein) may certainly take
credit for making us see in the negative result of experiments
like those of Michelson, Rayleigh and Brace, not a fortuitous
compensation of opposite effects, but the manifestation of a gen-
eral and fundamental principle.” And again : “It would be un-
just to add that, besides the fascinating boldness of his starting
point, Ein-itein’s theory has another marked advantage over
mine, whereas I have not been able to obtain for the equations
referred to moving axes ‘exactly’ the same form as for those
which apply to a stationary system, ‘Einstein’ has accomplished
this by means of a system of new variables slightly different
from those which I have introduced.”

This was written in 1909 four years after the publication of
Einstein’s work on the Restricted theory, after the theory had
been tested by Kaufman and Bucherer in connection with the ex-
tremely rapid moving /3-rays establishing the forms for the longi-
tudinal and transverse mass of the electron as :

mo mo

m,= ^ ni(. =

V(I=|)» v“i=|

distinguishing between the instantaneous motion in the x-di-
rection as transverse, attaching these terms to the respective
masses. At the present time the form has been simplified agree-
ing with that given by Lorentz in 1904, namely :

mo

m=

VI-

274

PAUL BIEFELD

where m is the mass in motion, m^ the mass at rest of the electron.

The principle is, however, not only true in connection with
masses of electrons but also with respect to every ponderable
mass as will be shown later.

Returning now to equations (3) and (3a) we will introduce
the so-called ‘light time,’ l=ct; using this, these equations be-
come :

2( — Al-) =0

(9)

2(Ax'=— Ar-)=o

v '

(9a)

and the Lorentz transformation makes (9) a covariant equation
which is satisfied with reference to every inertial system K', hav-
ing a uniform rectilinear motion relative to K, if it is satisfied in
the system K to which we have referred the two events : emission
and reception of electromagnetic radiations or light.

At this point the genius of Mincowski steps in, introducing. the

time coordinate: x^=il (i=V - 1)

and equation (9) becomes:

2x“ =0 V from 1 to 4

y

(10)

and (9a)

' .

2x'-=o V from 1 to 4

(10a)

r

Thus putting at once the time coordinate formally on the same
footing as the space coordinates Xo, x,. We say formally only
because the relation of rationality must be considered. The space-
time frame of reference of (10) and (10a) is Euclidean with one
imaginary coordinate.

A point x^, X., x^, x^ is called a ‘world-point’ and the line gener-
ated by the same a ‘world-line,’ and the continuum th'^ ‘world.’
All events present themselves to the observer as intersections of
world lines. Thus the event “twelve o’clock” as observed on a
watch comes to us as the intersection of a world line through a
point on the dial with a world line through -a coincident point on
the hands of the watch.

We shall now give another interesting consequence of the re-
stricted theory.

According to this theory the conservation of mass, or more

THEORY OF RELATIVITY

275

?.trictly speaking of ‘inertia mass/ has lost its meaning and is
merged, as was indicated in the introduction, with the principle
of the conservation of energy.

We have already treated of the change of mass of electrons by
virtue of their motion and indicated there that the same was
true of any mass. This comes about in the following way. The
inertia mass changes if it takes up energy of radiation from
without. The kinetic energy of a point mass in the pre-relativity
mechanics is expressed by :

mv“

.

according to relativity by :

mc-
V 1—

c-

This expression becomes infinite as v approaches c, showing in
the first place that it can not become equal to c, involving as this
would an infinite amount of kinetic energy possessed by a point
mass.

If the expression above is expanded in series we have :

V“ 3

mc'+m — 1 m — / . . . .

2 8 c^

The second term is the one standing for the kinetic energy in
the old mechanics, the third term is very small if is small

in comparison with unity, and the first term does not con-
tain v; its meaning will come out in the subsequent discussion.
If a moving body according to electrodynamics takes up the en-
ergy E in form of radiation, the increase of energy becomes :

Vi— ^

c-

and the energy of the body becomes :

(m-j- ^ )c-

This body has therefor the same energy as a body of mass :

Fo

m-^

c-

276

PAUL BIEFELD

If we write the expression in the form :

mc“-[-Eo

we see that the expression me- in the expansion is the energy
which the point mass possessed before the body took up the
energy E .

The General Theory of Relativity.

' (Theory of Gravitation).

The restricted theory is valid only in connection with bodies
or frames of reference in uniform rectilinear motion relative to
each other. There is no reason thinkable, however, why such
systems should be preferred for other systems having any kind
of motion ; for we find nowhere in nature any such distinction
indicated either in bodies or in the concept of motion. We are
compelled then to look for the distinction as resting in the ob-
jective properties of the space-time continuum. We must at-
tribute to this continuum a “field property” as we do in case of
the electromagnetic field ; and then find, a way to extend the prin-
ciple of relativity to frames of reference in non-uniform motion
relative to each other.

We find a way of attack by the following consideration. In
physics the ratio of the masses of two bodies is defined in two
ways : first, as the inverse ratio of the accelerations imparted to
them by the same force producing the motion ; second as the
direct ratio of the forces acting in the same gravitational field.
In the first relation we call the mass “inertia mass” in the second
“gravity or weight-mass.” The ratio of these two masses have
been found by Oetvoes so nearly equal to unity that the deviation
is of the order of less than 5xl0-\ The examination included
substances of crystaline structure and of radioactive nature. In-
ertia and gravity mass are then not only proportional but strictly
equal. We have, however, no right in face of these results to
maintain such an equality in thought unless it is reduced to
an equality of nature of the two concepts. The statement of the
equality of inertia-mass and gravity-mass is equivalent to the
statement that the acceleration imparted to a body in a gravita-
tional field is independent of the nature of the body ; and it is the

THEORY OF RELATIVITY

277

extension of the principle of relativity that will establish the
equality of the real nature of the two concepts.

A simple hypothetical experiment pointing to this extension
will make the point made in the last paragraph clear. Let us
consider a cubical box of sufficient size so that an observer pro-
vided with appliances for experiment finds room in the same. We
further conceive of this box so far away from all bodies or masses
so that it is not influenced by them in a gravitational way. The
observer will experience great difficulty to stand upright. When
lying on the floor the least Impulse will send him to the ceiling.
When he lets go of an object in his hand it will not fall to the
floor. A body attached to a string fastened to the ceiling will not
stretch the string unless pulled down by the observer which he
would find hard to do on account of the instability of the bodies
involved.

Let us now imagine a rope attached to the outside of the box
and some being begin to pull at the same upward with a con-
stant force, giving the box a uniform acceleration. The man in-
side the box will at once be able to stand upright in the box. Let-
ting go of an object it will fall to the floor; looking at the body
on the string he will see it hanging vertical with the string taut.
In view of the observed facts the man has every reason to be-
lieve that he is in a “gravitational field.”

Now let us further imagine an observer located at rest in space
some distance to one side of the box. This observer would be of
different opinion from the one in the box ; he would say, the rea-
son the string hangs taut and hangs in a vertical direction is due
to the “inertia” of the upward accelerated box ; and give a simi-
lar explanation with regard to the other phenomena occuring
there.

The observer in the box then attributes to the body on the
string “gravity mass” ; the observer outside the box, “inertia
mass.” The two concepts are identical and, moreover, inde-
pendent of the nature of the body.

Within the box the actual acceleration of bodies is strictly
“equivalent” to a gravitational field.

We may now substitute for the box a frame of reference K'
limited, however, to the confines of the box; and for the region
outside, where the second observer is located, a frame of refer-
ence K. K' is uniformly accelerated with respect to K. Relative
to K' or as seen from K', K is uniformly accelerated. K', as seen

278

PAUL BIEFELD

by the observer within, is at rest and a gravitational field pres-
ent. This gravitational field may then be legitimately replaced,
within the limits of the box, by the accelerated coordinate sys-
tem K'. This principle of equivalence is evidently intimately
related to the equality between the inertia-mass and gravitational-
mass, and leads thus to the extension of the principle of relativity
to frames of reference that are in non-uniform motion with refer-
ence to each other. Again this conception leads to the unity of
the nature of inertia and gravitation.

It is to be noted, however, that a gravitational field can be re-
placed by a frame of reference having a uniform acceleration only
within a very limited portion of space ; about in the same way as
we can think of a plane sheet of paper being in contact with a
curved surface over only a very limited part of the surface.
Nevertheless the principle of equivalence gives us the correct
mode of attack to conquer the difficulties of the general theory of
relativity. For as Einstein says in his Princeton lectures of
1921 : “The possibility of explaining the numerical equality of
inertia and gravitation gives to the general theory of gravitation,
according to my conviction such a superiority over the conception
of the classical mechanics, that all the difficulties encountered in
the development must be considered as small in comparison.’'

In the general theory then we must do away with preferred
systems of reference of any kind, the term ‘gravitational field’
involving all arbitrarily moving frames of reference of any kind.

Let us now consider one of the simplest of such fields present
in case of a rotating system. Let K' be a frame of reference
whose x'3-axis coincides with the Xg-axis of the system K at rest.

We put the question : Are the configurations of rigid bodies at
rest relative to K' (that is, moving with K') in accord with
Eculidean geometry?

As K' is not an inertial system we do not know directly the
configurations of rigid bodies with reference to K'.

Let us take a circle in the x\ — x'2 plane and a diameter of this
circle. Further let us place a sufficient number of very small
rigid rods of the same length along the circle and the diameter ;
then the ratio of the number in the circle to the number in the
diameter come out equal to tt. Let now the system K' be rotated
with uniform angular velocity about x'^-axis . We will now find
that more rods will have to be placed along the circle while none
need be added to the diameter. This is easily explained ; for the

THEORY OF RELATIVITY

279

rods along the circumference suffer a Lorentz contraction while
those along the diameter do not. The ratio of circumference to
diameter now comes out greater than tt. From this follows that
the laws of configuration of rigid bodies does no longer conform
to Euclidean geometry. Again if we place two synchronous
clocks, one in the center and one in the circumference of the
system K' in uniform rotation, the latter will go slower if ob-
served by someone at the center. From this follows that space
and time can not be defined with respect to K' as they were in the
restricted theory.

According to the principle of equivalence K' is here also to be
considered as a frame of reference at rest with respect to which
a gravitational field is present. (Field of centrifugal force). We
must then come to the conclusion that a gravitational field in-
fluences and in fact determines the metrical properties or the
‘metrics' of the time-space continuum. If then the laws of con-
figuration of rigid bodies are to be expressed geometrically, the
geometry is non-Euclidean.

A similar situation presents itself in the consideration of gen-
eral two-dimensional surfaces as intimated above. On the plane,
Cartesian coordinates , x^ will suffice to measure any portion
of the same by means of rigid measuring rods ; not so on the sur-
face of an ellipsoid for instance. Gauss introduced curvilinear
coordinates to overcome the difficulty, which satisfying the con-
dition of continuity are wholly arbitrary otherwise, (ffexible
threads take the place of shord rigid rods). Later these co-
ordinates were related to the metrical properties of the surface.
Then Rieman extended the dimensions to any number, establish-
ing infinitesimal geometry to n dimensions in which the general-
ized Pythagorean theorem holds. Applying this to our space-
time frame of reference of the general principle of relativity we
have the arbitrary coordinates x^ , x^ , Xg , x^ numbering uniquely
‘world points' and the invariant interval between two such points.
ds“=g dx dx G from i — 4 g =g

ILLV U V I^V fXV VtX

in which the g describe with respect to the coordinates the

UM

metrical relations of the continuum and at the same time the
gravitational field.

The above expression expanded would become :

ds2=g dx^+g, dx^-f g^ dx^-j-g dx2+2g dx dx -f-2g dx dx

®11 1 ‘ ®22 2 ' ^33 3 ' *^44 4 ' "l2 1 2 ' ®13 1 3

+2g„dxjdx,+2g,3dx,dx3+2g2,dx,dx4+2g34dx3dx.

280

PAUL BIEFELD

The g’s are functions of the infinitesimal coordinates; mathe-
matically they are quadratic functions of the infinitesimals.

The /XV may be represented by the symmetrical array:

we need only:

11

12

13

14

21

22

23

24

31

32

33

34

41

42

43

44

11

12

13

14

22

23

24

33

34

but as the /xv's =

/XV s = v/x «

44 which are the double subscripts
occurring in the above expansion.

In case of the absence of a field of force, the equation becomes
that of the restricted theory :

ds^=-dx2-dx“-dx^-|-dx2

1 2 ;! ' 4

in which x^, x^. x. are imaginary space coordinates and dx^ the
real time coordinate that can be measured directly by means of
a clock. The g’s in this case are represented then by the fol-
lowing array:

—10 0 0

0—1 0 0

0 0—1 0

0 0 0+1

As a concrete example we will consider the transformation to
rotating axes, the rotating system mentioned on page 278.

The infinitesimal space-time interval of the frame of refer-
ence is represented by :

ds“=-dx^-dy--dz2+dt-

let Xi, X2, X3, X4 be any functions of x, y, z and t then :

dfi ^ 5fi 6'fi dt^

dx=: — dXi -1 dx2 4 dx3 -j dx^ . . .

o'Xi ('^Xo 5x3 ■' ax.

and this will lead us to the expressions holding in the general
theory namely :

ds^— g as given above.

/X V
1-4

The relations for transforming to rotating axes are :
x=Xi cos 0JX4 — X2 sin o)X4
y=Xi sin (0X4+X2 cos wX^

Z = X3

t^x^;

THEORY OF RELATIVITY

281

and we have:

dx=cos tox^dxj — sin ojX^dx2 — w(Xi sin ojx^-fx2 cos wx^)dx4
dy=sin o^x^dx^+cos o)X^dx.,-^o)(x^ cos o^x^ — Xo sin o^xjdx^

dz=dx..

dt=dx.

Substituting in the equation for ds“ we have:
ds^= — dx^ — dx^ — dx^-f [ (1 — or) (x^4-x“)]dx^

+2(0X2 dxi dx^ — 2(oXi dx2 dx^

Comparing this with the expression for
ds-=g^^ dxj+g^+x; ....

we get the values of the g’s :

g.2= —1

£'!= [(1— <'^=) (x_f+x^^)]

2g,4= 2a,x,

2g.,t= — 2wX,

or the array is :

— 1 0 0 0JX2

0 — 1 0 — (ox^

0 0—1 0

0 0 0 [(1— or) (xi+x:)]

If we put: |o)+x^+x^)=0 then g4i= 1 — 2q, repre-

sents the potential of centrifugal force, or a special type of
gravity-potential.

Although the g’s represent the metrical properties of the
space-time continuum, we do not ordinarily look upon them as the
field produced by rotating axes. We have other means like the
gyro-compass or Foucault’s pendulum to present such a field to
our minds, yet the field is nevertheless defined by the g’s and as
seen especially in this case, by the g44.

It must therefor be possible to represent the gravitational
field in the specific sense by the g’s, and Einstein has accom-
plished this by finding the differential equations satisfied by the
g’s representing this field. These differential equations for the
generalized potential express the law of gravitation of Einstein
just as the Newtonian law of gravitation is represented by:

A^(pz=0

282

PAUL BIEFELD

It is important that the two-fold meaning of the g’s be fixed in
mind, namely, that they on the one hand express the metrical
properties of space and on the other the potential of a field of
force. In the absence of such a field of force the field is called
Galilean — in which the law of inertia holds and the g’s are rep-
resented by the array :

—10 0 0
0—1 0 0
0 0—1 0
0 0 0+1

It is hardly to be attempted here to go into details in deriving
Einstein's law of gravitation, as that would involve the develop-
ment of tensor analysis ; but a few interesting facts in connection
with the same should be mentioned here.

The complete mathematical analysis had been developed before
Einstein attacked the problem. The theory of tensors by Rie-
mann and Christoffel in 1867 and 1896 respectively and by Ricci
and Levi Civita in 1901 in connection with the theory of sur-
faces, non-Euclidean geometry and absolute differential calculus
including tensor analysis lay ready at hand.

As an example of tensors may be mentioned the fundamental
covarient tensor g/xv of the second order, used in connection with
the transformation to rotating axes above. A tensor of the first
order is identical with a vector of common vector analysis, and a
tensor of zero order is identical with a scalar. Like vectors, ten-
sors are represented by their components. Tensor analysis rep-
resents a very powerful tool for the development of the general
theory of relativity, symbolizing the laws of nature in connec-
tion with a space-time frame of reference that are consistent with
the laws of relativity.

Mathematical and Experimental Tests of the General Theory

of Relativity

Before going into this matter it is well to keep in mind that
we are not concerned with the +roof' of the theory. Einstein
himself has said, that no amount of experimental demonstration
could prove him correct; and that a single experiment could at
any time prove him incorrect.

We are concerned only with a theoretical, experimental or ob-
servational test of phenomena predicted on the basis of the

THEORY OF RELATIVITY

283

theory. Only three of these tests have so far been suggested by
Einstein as possible; the fact being that Newton’s law is a very
close approximation to Einstein’s law, the latter being capable
of degeneration into the former.

Tests.

First: To account for the inconsistence of the observed ad-
vance of the perihelion of Mercury with the theoretical value
based on Newton’s law of gravitation.

That theoretical astronomers did not know what to do next
concerning the discrepancy after trying various schemes follows
from the words of Simon Newcomb in his ‘Astronomical Con-
stants’ : -Tn case where our ignorance is complete all hypotheses
which do not violate known facts are admissible.” But there
was no hypothesis that could make goood.

According to observation the line of apsides of the orbit of
Mercury revolves in the direction of motion of the planet about
the Sun through an angle of 574 seconds of arc in a century. The
angle calculated from the perturbations of the planets accounted
only for about 531" leaving a remainder of 43" that could not be
accounted for.

Einstein’s calculations based on his theory of gravitation
showed that the Sun’s gravitational field at Mercury produced
the additional 43" per century required. The effect of the Sun’s
field on the other planets according to the same law is quite small,
on account of their distance from the Sun, amounting to about
8" in the case of Venus, about 4" in the case of the Earth and
still smaller amounts in case of the remaining planets. The
striking feature of the calculation is the absence of any adjust-
able constants in the formula used. The only constants appear-
ing are the period of the planet, T, the semi-major axis of the
orbit, a, and the eccentricity, e.

Second : The curvature of rays of light coming from fixed stars
and passing near the Sun, due to the gravitational field of the
latter.

In the first place it follows from the general theory that light
travels slower in a gravitational field than in a region devoid of
such a field, moreover its path is not a straight line the equation
of the geodesic being :

8 j ds±o

or the geodesic in a field of force is curved ; the amount of curva-

284

PAUL BIEFELD

ture depending on the field strength in the region of the path.

Again a ray of light or electromagnetic radiation possesses
energy and hence the equivalent of 'mass/ consequently it is acted
upon by a gravitational field, the amount of bending depending
on the strength of the field from point to point of the path, and
varying besides inversely with the distance from the centre of
the Sun. At the surface of the Sun the deflection is predicted
to be 1".75

Why there should be a deflection due to the gravitational field
of the Sun may be seen by referring back to the principle of
equivalence in connection with the hypothetical box-=experiment.

Let us imagine the man to one side of the box firing a bullet
percenticular to the vertical wall of the box. The bullet will pass
through the box and out on the other side. In the space out side
it will fly in a straight line being in a field free of force; inside
the box, however, it will be deflected downward. Interpreted by
the man in the box as due tO' a gravitational field and by the man
outside due to the upward acceleration of the box. In the case
of a ray coming from a star the ray takes the place of the mass
of the flying bullet, by virtue of energy of radiation having the
equivalent of mass ; and the accelerated box being equivalent to a
gravitational field, taking the place of the Sun's gravitational
field. The analogy is oi course only approximate, the 'equiva-
lence' holding only within the confines of the box.

We will now give the results of the observational test of the

Light Deflections Observed at the 1919 and 1922 Eclipses

No. of

No. of

Ang. dist.

Range of

Eclipse

Expedition

Telesc.

plates

stars

fr. Sun

deflect

Res.'

P. E.

Observers

1919

Sobral

4", 19'

7

7

0.°5-l.°5

0."88-0."32

l."98

±."12

Dyson

May 29

Sobral

8", 11'

16

6-12

0. 5-1. 5

0. 88-0. 30

0. 86

±. 10

Eddington

Principe

8", 11'

2*

5

0. 5-1. 5

0. 86-0. 30

1. 61

±. SO

Davidson

1922

Wallal

6". 10'

2

18

0. 5-2. 6

0. 85-0. 18

1. 74

±. 30

/Chant \
\ Young /

Sept. 21

/ Cordillo\

\ Eowns /

3". 5'

2

14

0. 6-2. 9

0. 83-0. 16

1. 77

±. 30 1

fDodwell ^
1 Davidson/

Wallal

5". 15'

4

62-85

0. 5-3. 4

0. 85-0. 15

1. 72

-f-. 11

Campbell \
Trumpler /

Wallal

4", 5'

(3)* 135-139

0. 5-10. 4

0. 85-0. 04_

—

-- (

* 4th nlate not yet reduced.

Prediction by Einstein's Theory l/'75

The agreement with prediction is especially good in connection
with the 1922 eclipse. The last 4 plates, only 3 being reduced so
far, were especially taken to test the 'distance law/ For this

THEORY OF RELATIVITY

285

purpose a wide-angle lens (of short focal length) was chosen
giving a field of great range, recording stars at from 5° to 10°
away from the Sun, by means which that law was also confirmed,
the residuals, observation minus theory, coming out extremely
small.

Third : We have pointed out in connection with a field of cen-
trifugal force that a clock placed in such a field loses time. The
same would be true if a clock were placed in a gravitational field.
Now an atom is a periodic mechanism comparable to a clock.
Its period would be greater in the gravitational field of the Sun
than in that of the earth. As a consequence of this the spectral
lines of a substance in the vapor envelope of the Sun would be
shifted to the red as compared with the lines of the same sub-
stance produced on the earth. The relative displacement is about
the same as that produced by a radial velocity of recession of
0.63 kilometers per second, being of the order of 0.008 Angstrom

o

units measured in the region of A=3883 A lying almost within
the errors of observations. Nevertheless the results of Evershed
in 1918 and those of Grebe and Bachem in 1919 have offered con-
siderable evidence in corroboration of the prediction; while at
that time the findings of Prof. St. John of the Mt. Wilson solar
laboratories were not confirmatory. In September 1923, how-
ever, in a paper read before the Astronomical Society of the
Pacific he expressed himself as having come to the conclusion
that he had confirmed the Einstein effect relating to the above
shift of spectral lines ; and that in the future a correction would
have to be applied to spectroscopic measures.

At the last meeting of the National Academy of Science,
(Science, May 16, ’24) Prof. H. D. Curtis of Allegheny observa-
tory reported recent measures of Drs. Burns and Meggers:
“showing shift of lines very different from the simple and uni-
form amounts predicted by the relativity theory. Instead of all
the lines being shifted by an equal amount to the red and that
amount predicted by the Einstein theory, a very marked line-
intensity factor is found. That is, for very faint solar lines there
is little if any shift, and the amount of this shift increases as
the wider and stronger lines are used.” Then follow numerical
results showing the above; and finally, after some further re-
marks along the same line, the following conclusion: “Accord-
ingly the authors regard these results as a negation of one of
the so-called proofs of the theory of relativity.”

286

PAUL BIEFELD

In the judgment of the writer the above statements are hardly
conclusive. Similar findings were reported by Prof. St. John of
Mt. Wilson in the Astrophysical Journal Vol. 41, p. 62, 1915.
And Prof. St. John in a private communication to the writer
says quite correctly : ‘‘Curtis’ results showed the long recognized
difficulty that strong (high-level) lines of iron show a shift to the
red greater than the Einstein prediction, and the weak lines (low-
level) a red displacement smaller than that required by relativity.
This is at the center of the disk and the small differences from
calculated values taken care of by radical currents of small
cosmic velocities, upward near the photosphere and downward
at very high levels, I see no way in the absence of pressure to
account for these displacements without calling in relativity. At
the edge of the disk the currents are no longer in the line of
sight. The result at the limb is then a red displacement for both
strong and weak lines of the full relativity value and a little more,
this small excess being taken care of by differential scattering
which produces a slight asymmetry on the red edge. There is no
interpredation that will account for the red displacement at the
limb, other than relativity.”

These words coming from the greatest authority of solar spec-
troscopy in America and one of the greatest in the world, leaves
hardly any doubt that also this last prediction has stood the ex-
perimental test of astrophysics.

The test of this prediction and a confirmative outcome is of
especial importance for two reasons. The first is, that Einstein
himself maintains that ‘his whole theory of gravitation stands
or falls by the success or failure of this test’ ; second that, as
Eddington has pointed out, ‘if the displacement of solar lines be
confirmed, it will be the first experimental evidence that Relativ-
ity holds for quantum phenomena.’

Now a last word as to ‘gravitation’ itself. Newton assumed
‘absolute space’ and ‘matter’ essential and besides this the con-
cept of force acting between any two portions of matter in space.
He himself has said, that it is absurd to think of force acting be-
tween two bodies through empty space; but the inverse square-
law works, to at least a very close degree of approximation, but
it nevertheless remains ‘unreasonable.’ In Einstein’s theory
‘gravitational force’ has no place as a fundamental concept! It
is the ‘gravitational field’ analogous to the electrical and mag-

THEORY OF RELATIVITY

287

netic, or better, the ‘electromagnetic field' that is the physical
reality; and -this finds its expression as a metric property of
space; mathematically represented by a set of differential equa-
tions involving twenty functions which finding their place in
these equations express the curvature of the space-time con-
tinuum just as the Rieman ‘curvature components' do in three
dimensional space. If these twenty functions were zero, either
the gravitational field would not be present, according to Ein-
stein, or it could be ‘completely' removed by a proper change of
frame of reference. But we know that it can not be removed ex-
cept within a very small region. This means that there are some
essential ‘curvature components' that can not be done away with
by any choice of frame of reference ; in other words the twenty
curvature components are not ‘individually' equal to zero.
Einstein now reasoned that there must be some mathematical
relation corresponding to the physical properties of space-time
independent of the choice of frame of reference; and here it is
the genius of Einstein that makes the brilliant guess that certain
‘linear functions' of these curvature components are zero out-
side of matter and equal to a similar group of functions within
matter involving internal dynamical properties of matter itself,
of which the electron theory will give us more and more infor-
mation as time goes on.

The attempt has been made by Weyl and others to include
the electro-magnetic field side by side with or intrinsically con-
nected with the gravitational field, but Einstein says that such
considerations will not bring us nearer to the true’ solution of
the problem. According to him a theory in which the gravita-
tional field and the electromagnetic field enter as an essential
entity would be much more preferable.

Prof. Einstein has published a paper in the “Sitz. Ber. d.
Preuss. Akad," 1923, in which he presents this master problem
of “gravitation-cum-electro-magnetism" expressed in forty dif-
ferential equations characteristic in containing besides the funda-
mental covariant tensor g/xv of the gravitational field the funda-
mental covarient tensor Ffj.v of the electromagnetic field, includ-
ing of course also matter, as we usually do not think of it, namely
as nuclei or centres of electromagnetic action; or electrons and
protons exhibiting respectively negative and positive charges of
electricity.

288

PAUL BIEFELD

We may hope that also here experimental tests may present
themselves that may bring us nearer to the goal of comprehend-
ing the true nature of matter and energy, or more likely the two
as one, and that one would have to be energy.

The author acknowledges as his principal source for the above the
“Princeton Lectures^’ of Prof. Einstein, whose definitions will be recognized.
The section on a rotating system of coordinates is taken from Prof Edding-
ton’s “Report.”

/

SOME PROBLEMS OF TAXONOMY
A. W. Lindsey

During the past the pronounced tendency of systematists to
do little more than describe and name different species of plants
and animals was a prevalent and largely necessary evil. Even
so, the work of taxonomists was indispensable in the biological
sciences, and now that it is no longer without adequate founda-
tions, it can be of inestimable value. Its value, of course, must
depend to a high degree upon its usefulness to other branches
of science, but if we except the field of medicine, none of the
other branches have great intrinsic worth.

During the last thirty or forty years the classification of ani-
mals has been placed upon a sound phylogenetic basis which
renders the work of a thorough systematist of the present day of
much greater importance than the mere description and naming ^

of species. Account must now be taken of the morphology, ecol-
ogy and physiology of organistns, of paleontology where it serves,
and possibly of genetics. The discoveries of geneticists, so far,
appeal to the writer as incapable of wide application to the
problems of taxonomy, although they may easily furnish many
checks on the relationships of species and their subdivisions. The
modern systematist must be well grounded in all branches of
biology, and his work, in order to be reasonably accurate and
useful, must express the deductions of such training.

The dignity of taxonomy as it should be, then, is scarcely to
be denied, but it is all too true that many taxonomic works of the
present afford more than one opening for criticism. As a syste-
matic entomologist and a devotee of the Order Lepidoptera, the
writer has noted with many misgivings certain phases of this
matter which it is his purpose to discuss in this paper. Most im-
portant of these is the limitation of systematic divisions below
the genus, including the questionable practice of naming slight
variations. Closely related to this topic are the conflicting meth-
ods of naming such divisions, and last of all, one of the most
vexatious Questions in the classification of animals is that of the
stabilization of generic names.

289

290

A. W. LINDSEY

L The Species Concept.

The question of the existence or non-existence of species in
nature is one of such age that some hesitation must be felt in
attacking it. However, no discussion with which the writer is
familiar furnishes a satisfactory foundation for a practical sys-
tem of classification. All treat the species as a thing capable of
rigid definition, either actual or imaginary, and herein their
weakness seems to lie. In entering upon a discussion of this
point it will be well to consider some of the material which it
concerns.

In the insects, and in the Lepidoptera perhaps as much as in
any other order, we are dealing with a highly successful group
which has ramified considerably in adapting itself to- various
conditions of environment, yet still includes relatively generalized
forms. These are capable of becoming modified further in re-
sponse to changes of the habitats which they now occupy. As
extreme examples of the specialized types, Feniseca tarquinius
Fab. and the myrmecophilous Lycaenidae may be cited among
the Diurnals. Euxoa among the moths and Argynnis, Melitaea
and Euphydryus are good examples of the more generalized
genera. It must be clearly understood that all of these forms are
specialized in some degree, as, of course, all existing Metazoa
are.

Such forms as tarquinius may be passed over briefly. It
seems that everyone should agree in accepting them as well de-
fined, natural units to which the designation species is properly
applicable. In the writer's opinion there are many such species
whose existence as natural entities cannot seriously be ques-
tioned. Powers applies this idea of species in a sweeping way.
He states that “The whole spirit of modern biological research
seems to the writer to demand the conception of species as reali-
ties,— not all alike, in their reality, of course.”^

In contrast to this view, Montgomery says that “in Nature oc-
cur only individuals, as was clearly pointed out by Lamarck, and
is generally acknowledged at the present time, species and other
groups being arbitrary concepts.”- By an extremely rigid and
inclusive application of this view, it may possibly be regarded as

^ Studies from the Zool. Lab., U. of Neb., no. 95. Reprinted from the
American Naturalist, xliii, 1909.

^ Montgomery, On Phylogenetic Classification, Proc. Acad. Nat. Sci. Phil.
1902, p. 193.

SOME PROBLEMS OF TAXONOMY

291

affecting all existing life, for the possibility of variation within
some limit of degree and time is a fundamental provision of our
theories of phylogeny. These facts, however, are axiomatic, viz,,
that an organism’s power to vary and to adapt itself to change
of environment decreases with every progression, in whatever
direction, from the primitive condition of its ancestors, and that
there is an ultimate point beyond which the process of its evolu-
tion cannot go. That such a point exists, a point at which the
species itself enters a state of senility wherein any considerable
demand for further adaptation can result only in extinction, is
abundantly proved by the dinosaurs, pterodactyls, and other ex-
tinct forms of the past. Among existing animals such forms as
the birds of paradise and the head fishes appear to be senile to an
appreciable degree, and less conspicuous examples are found in
the Lepidoptera already mentioned. Such forms may easily be
recognized as natural entities.

For the .purposes of a practical system of classification it is
necessary to reach some basic idea of our unit and the way that it
is to be applied, and this idea must necessarily be applicable to
the entire subkingdom, if not to all living organisms. Many of
the so-called species of the present are in a state of senility as
pointed out, some are primitive but constant, while others are
either primitive or generalized, and very actively variable. It
is obvious both from past experience and from a logical consider-
ation of these facts, that the application of a single rigid concept
to the limitation of all of these groups is a difficult task. Here
the neglected element of time enters. Combined with senility, it
furnishes us with an ideal of the species as a natural unit which
we may define as follows : A group of individuals may exist as a
natural entity at any period of time in the phylogeny of the line
to tvhich it belongs ivhen the specialization of this group has pro-
ceeded to such a point as to preclude (a) the production of a
marked degree of future modification and (h) discernible inter-
gradation with other similar units, and in this state may be re-
garded as an ideal species.

After the elimination of such forms there remains the im-
mense number of living organisms which are not, at present, di-
vided into rigidly delimitable species. Perhaps after the passage
of many thousands of years these will have resolved themselves
into such species as were defined in the last paragraph, but here
again time is the important factor. These variable groups must

292

A. W. LINDSEY

be treated as they are at present, and together with groups of
all other degrees of stability. The transition is so gradual that
different terms cannot be used to designate conveniently the vari-
ous conditions, therefore it becomes necessary to arrive at an ac-
curate idea of the variable application of that now in use, namely,
species. Since, in a consideration of phylogeny, the present must
necessarily refer to geologic time, the result may well apply to
all scientific results of the past, and to the future beyond logical
prediction.

In order to be compatible with the ideal species, “species” se-
lected from the more variable forms should be definitely delimit-
able groups of individuals, regardless of the amount of variation
included. This is essentially the idea of Powersh Montgomery
expresses a very convenient idea of species, although with a very
different intent, which may be used in this connection. This is
found in his definition of a species as a “mental section of a line
of evolution.”^ The opinion has already been expressed that
these sections may be natural entities, and that in order to be
properly regarded as species, they must be. In other words,
in an hypothetical cross section of the phylogeny of all existing
forms, the species are those elements which are definitely sepa-
rable. When elements named as species in the past are found
incapable of separation, they must be regaredd as divisions in-
ferior to the species of this interpretation, and the species to
which they belong should be sought in a “section” of greater ex-
tent. The accurate arrangement of any of these elements in our
actual classification is, of course, fraught with considerable dif-
ficulty. Until our knowledge is more nearly complete and per-
fect we must expect constantly to revise our results; the careful
and diligent study of an abundance of material — ideal conditions,
to be sure, — may some day result in a classification of reason-
able stability.

It is not the writer’s purpose to present here a discussion of
the problems of transmutation of species,^ the influence of gen-
etics on the species concept-’ or the methods of limitation of
species,^ which are taken up in the papers cited. It is proposed
to suggest in this concept of species a basis for practical classifi-
cation. By reducing the application of the term species to groups

® Montgomery, cp. cit., p. 206.

^ Powers, op. cit.

® Davis, Species, Pure and Impure, Science Iv, no. 1414, pp. 107-114, 1922.

® Montgomery, op. cit.

SOME PROBLEMS OF TAXONOMY

293

of individuals which are at the present time delimitable, with-
out regard for the extent of variation embraced by any one, it
should be possible for the average worker, as well as the specialist
with extensive resources, to become familiar with the chief units
of any division. The next difficulty is the treatment of the sub-
ordinate divisions of such extremely variable species as some of
those included in Euxoa. In discussing this, although a degree
of unwelcome complexity is thus introduced into the second part
of this paper, it will be convenient to take up in rather intimate
association the methods of subspecific nomenclature and the
value of the various subdivisions.

II. Subspecific Divisions.

In the first topic of this paper the species concept was dis-
cussed, with the conclusion that the term species properly desig-
nates a natural entity consisting of a delimitable group of indi-
viduals. This was qualified by the addition of the element of
time, recognizing that the species of the present are in varying
stages of evolution, and that many of them may ultimately re-
solve themselves into more nearly ideal species. As the ideal
species, senile forms which had run through their possible phy-
logenetic development were mentioned. The purpose of the sec-
ond topic is the discussion of the subdivision of the more gener-
alized and variable species of the present, and the nomenclature
to be applied to their subordinate parts.

Formulating the problem as a generally applicable hypothesis,
rather than as a specific case, let us consider the ways in which
these variable groups have been treated. We may examine them
as two hypothetical species, both variable. Each in its entirety
may be regarded as a well defined '‘cross-section,’’ the first made
up of a number of fairly definite subordinate sections and the
second of scarcely separable subordinate components. The two
may be likened to a cellular tissue in comparison with a syn-
cytium.

The first hypothesis finds many examples in existing species
which occur in two or more forms, usually well marked. The
early method of treating such species was to accept the form first
named as the species and those discovered later as varieties. If
an occasional specimen appeared showing a marked variation
from the normal, it was, and still is, known as an aberration.
Many of these bear names. This simple subdivision of species

294

A. W. LINDSEY

was long- accepted as sufficient, but increasing inquiry into phylo-
genetic relationships has shown that with such an arrange-
ment forms of indubitably different value are often accorded
the same rank.

Some writers deny the right of the original specific name to
stand alone if any named variations exist.^ This makes neces-
sary the use of a trinomial for the correct designation of any
form of a variable species. The following paragraph by Hartert,
Jourdain, Ticehurst and Witherby® is pertinent in this connec-
tion : “As the use of trinomials for subspecies — or better, geo-
graphical or local races — does not seem to be generally under-
stood, it may be here explained that when a species is divided into
two or more races, or when two or more species are grouped as
races of one species, then each of these races must have a tri-
nomial appellation. It is impossible to say which is the oldest
or parent form, therefore the first named race of all those grouped
under one species is arbitrarily taken as the typical race, and its
name becomes that of the species.’’

Other writers have adopted a very logically conceived division
of the variations into forms and geographical races, a method
of subdivision which was very successfully employed in the most
recent check list of North American Lepidoptera.® In this list
Dr. McDunnough also drew on the work of Mr. Roger Verity^^
for another form of subdivision, the seasonal generation, exempli-
fied in Pieris napi Linn. This species is listed in our fauna with
seven races, two of which are accompanied by named aestival
generations, and in addition to these seven, three vernal genera-
tions with accompanying aestival generations. According to the
lettering used, the vernal generations are ranked with the races.
This method of division, though it undoubtedly has its faults, ap-
pears to be by far the most accurate indication of phylogenetic
relationships yet devised for expression in a linear series. We
must recognize the existence of geographical races, of which an
excellent example, based largely on genitalic structure, is found
in Hesperia tessellata race occidentalis Skinner.^^ Likewise the
existence of seasonal generations has been proved beyond doubt,

In Lepidoptera. see Rothschild & Jordan, Revision of the Sphingidae.

* A Hand-List of British Birds, pp. ix-x, 1912.

® Barnes & McDunnough, Check List of the Lepidoptera of Boreal Amer-
ica, 1917.

Verity, Rhopalocera Palearctica.

” Barnes & Lindsey, Ent. News xxxii, 79-80, 1921.

SOME PROBLEMS OF TAXONOMY

295

most conspicuously in the Indian fauna of the wet and dry sea-
sons, but quite evidently in the various forms of P. napi Linn.
Aberrations are known to every systematist and the name is self
explanatory. Varieties have been confusing in that the term has
been made to include everything not nimotypical. In the check
list mentioned the terms form and race have been substituted for

variety. A form is regarded as a variation occurring side by side
with the nimotypical form, in contrast with geographical races,
which are variations occurring in a region distinct from that oc-
cupied by the nimotypical form. This substitution seems to be
so successful that it permits the discarding of variety as an obso-
lete term. In order to present the consideration of these sub-
divisions more graphically I have drawn diagram A, assuming

29C

A. W. LINDSEY

for its basis an hypothetical species showing all of the variations
in question. This might well be regarded as a part of the evi-
dence furnished by P. napi, but introduces elements not observed
in that species.

In this diagram the three circles represent three hypothetical
cross sections of the species, each of which may be regarded as a
somatic generation. The central element in each of these may
represent the basic form of the species, and may, for convenience,
also be regarded as nimotypical. The axial line through the
three z elements represents the main line of the germplasm, al-
though the complete connection of the three generations must
necessarily be regarded as the cylinder of which they are cross
sections. That part of the three generations not included in the
nimotypical form is divided into a geographical race w, a form
y, and a third element, x, including alternating vernal and aesti-
val generations. W and x are assumed to show aberrations. In
the natural state, the probability is that w would produce only
w, although the available evidence suggests that artificial change
of environment would lead to the production of each from the
other. Y and z, occurring in the same region, would be pro-
duced from each other. As worked out by Verity in P. napi,
X may represent a definite line.

Designating the genus as G, trinomial nomenclature would
name these forms Gzz, Gzx, Gzy and Gzw. In the case of the
second a puzzling situation presents itself. We have already
chosen to apply to the entire species the name which has priority.
If we continue this by assigning to one of the seasonal forms
priority over the other, a complete designation of the latter in-
volves the use of a cumbersome, quadrinomial, and any minor
variation which might receive a name would carry it one step
further. Another difficulty with such a species is that a thor-
ough analysis may give us a series of aberrations, such as Gzw
ab. and Gzy ab., which are distinguished at least in part by the
same characters and named only upon a basis of their origin.
This is not common, of course, but in the insects is by no means
hypothetical. Can it possibly be regarded as necessary for the
purposes of classification to toil with such a series of names?
No matter whether such an aberration is among the progeny of
w, or y, it is the product of the same germ plasm, apparently in

Reiff, The Lepidopterist i, 15, 1916. Dyar, The Lep. i, 31, 1917.

SOME PROBLEMS OF TAXONOMY

297

response to the same stimuli, and as such may be designated by
reference directly to the nimotypical form with at least suf-
ficient minuteness for ordinary use. For genetic considerations
these minor forms may be treated without naming, as will be
mentioned later. We should note, before leaving this matter,
that in most cases such divisions as have been discussed are
based upon differences of color and pattern, which are apparently
quite directly responsive to changes of environmental condi-
tions. When lines such as w, x and y occur, their existence is
probably due to slight normal differences of environment, and
we must recognize that the fiuctuaticns of meteorological con-
ditions might easily result in temporary similarity of these nor-
mally different conditions of existence, such as would produce
forms and aberrations like those under discussion.^® If the simi-
larity of these is complete, they may certainly be named as one ; if
partial, as in the case of the Catocala arnica forms mentioned in
the paper last referred to,^® they are certainly not worth sepa-
rating from their parent forms.

The problem presented by this type of variation, involving
only a moderate number of forms in any species, and these
fairly well marked, is comparatively simple. It is essential, in
the first place, to have a name which may be applied definitely
to the entire species, and there is no serious objection to the rule
of priority now applied. In a few cases, as Papilio glaucus Linn.,
a subordinate form has priority. When, as in this case, the
nimotypical form occurs in only one sex, the necessity for modi-
fication is strongly suggested, but the simple application of tri-
nomial nomenclature is an ample measure.

With regard to the use of polynomials to indicate the com-
plete relationship of the ultimate division with the nimotypical
form, personal opinion must enter. As matters stand at pres-
ent this unavoidably leads to cumbersome combinations. Neither
modern system of nomenclature eliminates these, yet these sys-
tems have points of value which we should be reluctant to sacri-
fice. If the pronounced tendency were not present among ento-
mologists— I feel inclined to say lepidopterists in particular — to

In dealing with such superficial characters as distinguish most minor
forms and aberrations, the question of reversal can hardly enter. More
fundamental modifications such as would involve this question do not, in
any case known to the writer, furnish the basis for such a complexity of
nomenclature as is here discussed.

298

A. W. LINDSEY

name the most minute variations, I should favor the use in this
field of a combination of the trinomial method with the subdi-
visions of Barnes and McDunnough's Check List, but because of
the existing tendency, such a course seems to defeat the object
of systematic science. What is the use of a named race, form or
aberration which is so rare or so obscure that only a few special-
ists in the country can determine it ? Such fine ramifications can
be traced out without the application of names, if, indeed, they
are worthy of notice, and the studies recorded still be made avail-
able to the few who will carry them on. The names applied to
minor forms are usually an inert encumbrance of the nomencla-
ture, at the best, and are a hindrance to many in a branch of
science which should be efficiently helpful to all.

This brings us to the question of the actual value of variations.
I think that no one will fail to agree that such a conspicuous
thing as Vanessa antiopa ab. hygiea Heyd. is worthy of a name,
or that Poanes hohomok 0 form pocahontas Scud, is quite dis-
tinct from the normal female and worthy of independent desig-
nation. In the later, however, there has recently appeared an-
other named division, Poanes hobomok O form pocahontas ab.
friedlei Watson.^^ Some of our leading lepidopterists have been
guilty of actions almost as objectionable, but in this case a serious
weakness is found in the fact that the unique type was reared
under artificial conditions. The type itself is described as an
abnormally dark pocahontas with reduced maculation — char-
acters which go hand in hand in the Hesperiidae. It was reared
with one other specimen, a male, which is also noted as ex-
ceptionally dark. Add to this the fact that the conditions of
rearing might reasonably be expected to favor melanism, and
no conclusion seems possible save that the name is utterly use-
less. In my series of thirty or forty specimens of hohomok I
have traced a gradual transition from the normal female to very
dark melanic forms in which three or four stages equal in value
to friedlei can be distinguished. What possible good could come
of naming them?

No doubt many names such as that discussed in the last
paragraph are applied by men who have too little material for a
proper appreciation of the general characteristics of a species.
Diagram B will serve to illustrate our consideration of this prob-

“ Watson, Jn. N. Y. Ent. Soc. xxviii, 232, 1920.

SOME PROBLEMS OF TAXONOMY

299

lem, which is intimately associated with the second of our hypo-
thetical species. However, it might well be based on such a
species as Euxoa tessellata Harris or E. messoria Harris. The
entire diagram represents the hypothetical cross section, the
species under consideration. Z, the inner circle enclosed by an
unbroken line, may again be taken as the basic and nimotypical
form, overlapped as represented by the dotted circle, by each of
the variations v, w, x and y. These variations, whether races or
forms, may also overlap each other as shown. Obviously, to a
nan possessing series or specimens only from the sections b of
these variations, they would seem abundantly distinct and de-
serving of names. By supplementing this material with other
specimens from the a zones he would at once perceive their inter-
gradation and the necessity for great circumspection in their
treatment. Such variations appear to be incipient forms, possi-
bly incipient species, but at such an early stage in their evolu-
tion that their right even to be named may be seriously ques-
tioned. All belong to species z, and to any but a laboratory
scientist or a student of heredity the simple binomial Ga would
be much more useful that a long series of named, intergrading
forms. The work done in late years on heredity in Drosophila
is an excellent case in point.^^ What a galaxy of named Droso-
phila forms we should have if the geneticists showed the same
tendencies as some of our systematists ! Another unfortunate
feature of such species is that they may produce a distinct form
such as u. The probable treatment of such a form would be
assignment to a rank equal to that of v, w, x and y, although it
alone might deserve to be called a form or race. I venture the
assertion that many species of our present classification, at
least in the order Lepidoptera, will fit more satisfactorily as sub-
divisions in such a classification as this than in their present
arrangement. Mr. F. H. Benjamin has already done an excel-
lent piece of work on this basis in the genus Lampra Hiibner
( Rhynchagrotis Smith)

Although, as is natural, the foregoing considerations have been
illustrated by mention of insects whose study gave rise to them,
an attempt has been made to formulate them in such a general
way that each individual may adapt them to his own fund of

Morgan et al., Mechanism of Mendelian Heredity, 1915, and other works.

Benjamin, F. H., A Study of the Noctuid Moths of the Genera Lampra
Hbn. and Cryptocala gen. nov., Bull. S. Cal. Acad. Sci. xx, part 3, 1921.

300

A. W. LINDSEY

knowledge. They propose to show that the most satisfactory
and accurate system — or systems- — of nomenclature yet pro-
posed has become a burdensome vehicle under present condi-
tions,^^ but that this fault is due rather to the useless splitting
of species into subdivisions of increasing minuteness than to
any defect of the system itself. If only the workers who take
delight in naming minute variations would curb this tendency or
transfer their affections to other fields! Considering again the
science of entomology, the biological and ecological study of in-
sects supplies an inexhaustible and intensely interesting field.
Moreover it is available on every hand, it does not require the
formation of troublesome and expensive collections and libraries,
and ones activities can be adapted to such apparatus as he can
secure. It is essentially the field for the individual worker,
wherein he may do accurate and valuable work if he only will.

III. The Stabidzation of Genera.

A very troublesome phase of systematic work is the instability
of nomenclature. Three classes of names are involved, viz.,
specific and minor, generic and subgeneric, and those of major
divisions. The first have caused very little trouble, for the simple
recognition of priority is the sole requirement of all taxonomists
save a few classical purists. The last have also been the source
of little dispute. Generic and subgeneric names, however, are
the source of infinite difficulty, and offer a problem which seems
little nearer to solution today than a decade ago.

When a writer, in describing a genus, fixes its type, no mis-
interpretation can be made save through the improper associa-
tion of species, which is outside of the pale of nomenclature.
When a genus is erected to contain a single species this logically
becomes its type and the case is equally clear. It is the genera
described before the necessity of type fixation was recognized,
usually to include a motley aggregation of species, which cause
so much trouble.

The difficulty of fixing the types of such genera has long been
recognized, and several codes have been published for the direc-
tion of this work. Of these the writer feels competent to discuss
only those for the use of entomologists, since it is with these

” I am indebted to my friend and colleague, Dr. T. C. Stephens, for the
information that when the trinomial system was originated, this ultimate
difficulty was suggested by British Ornithologists.

SOME PROBLEMS OF TAXONOMY

301

alone that he has had practical experience. The earliest which
we need to consider is that of Walsingham and Durrant.^® This
code formulates the method of fixing the types of genera which
was in common use until the present century, and appears still
to be favored by some European scientists. The most important
principle involved is its acceptance of restrictions. In all codes
the first provision is that the type shall be selected from among
the species originally included in the genus, and this is the only
restriction now generally accepted as affecting the fixation of the
type. The rules formulated by Walsingham and Durrant, how-
ever, express the principle so widely followed in the past, provid-
ing that if any writer used the genus subsequent to its descrip-
tion, and eliminated part of the originally included species, the
type must be selected from those of the originally included species
which he retained in the genus. In some cases this may be very
reasonably applied, but it is weak, and hence scarcely to be con-
sidered as a generally applicable rule for the following reasons:
First, in the early days of entomology, works covering the en-
tire animal kingdom, y.et of some scientific pretension, were often
published. Obviously such works could not attempt to mention
every known species unless they were purely systematic, hence
only a few, or even one, was mentioned as an example of each
genus. No intention of the writer to restrict the genera by such
means can reasonably be assumed, yet such a citation of a single
species in illustration of a genus has been taken as a valid fix-
ation of the type. A good example is the genus Hesperia Fab.
This genus originally included all of the Lycaenidae and Hes-
periidae. Cuvier mentioned it, citing malvae Linn, alone as an
example.-'^ It is argued by some writers that this action fixes the
type, but it is quite clear that the inclusion of this particular
species was incidental. Thirty-nine years later another work of
Cuvier made the same citation, with a footnote which indicates
that his use of Hesperia was intended to be identical with that of
Fabricius."^ A second weakness with these restrictions is that
they may be due to the fact that the restricting work dealt with
only a limited fauna, or a certain collection, as in the case of

Lord Walsingham and J. Hartley Durrant, Rules for the Regulation of
Nomenclature, London, 1896.

The International Rules provide also for the designation of types of
genera originally described without included species.

^ Cuvier, Tabl. Elem. 592, 1798. Fide Scudder.

Cuvier, Animal Kingdom iv, 285, 1837.

302

A. W. LINDSEY

Stephens’ treatment of Nisoniades Hbn.^^ Scudder oast out
Stephens’ citation of tages alone under this genus for other rea^
sons.^^ The one commendable feature of this rule is exemplified
by the history of Polyommatus Latr. It seems reasonable that an
author’s modification of his own genus, especially when he treats
all of the species concerned, should be recognized even without
actual citation of a type. The difficulty here lies in impossibility
of drawing the line at all if we wish to admit some restrictions,
and if we admit all, it is impossible ever to predict the stability
of the nomenclature. At any time some obscure work of no great
value may be brought forward to play havoc with current usage.

The second code is that published by Banks and Caudell.^^ It
is an admirably worded, clear and concise series of rules, and 1
am aware of but one objection to it, viz., that it permits a species
to be the type of only one genus, unless, of course, it should be-
come the orthotype of a second through oversight. This is in-
nately weak in that it robs actual type citations of their concrete
value. Under such a rule the citation of the type is useless with-
out a reasonable degree of certainty that it has not previously
been cited as the type of another genus. The most important ob-
jection to this rule, perhaps, is that it conflicts directly with the
International Rules.

These, the International Rules of Zoological Nomenclature, are
the code which has by all means the best claim to the consider-
ation of Zoologists. They were formulated by a committee of the
International Congress of Zoologists, supposed to be representa-
tive of the various opinions obtaining on the subject of nomencla-
ture in scientific circles. The rules are supposed to arbitrate
differences of opinion and to arrive at the solution of greatest
fairness to all concerned. One of our leading lepidopterists ob-
jects to following them on the ground that the congress was not
truly representative, and that, in his opinion, certain type fix-
ations not in accord with the rules are perfectly valid. An au-
thority on another order of insects insists that Lamarck^-^ did
exactly the same thing as Latreille-® in citing examples of genera,
and that his citations should be regarded as valid type fixations,
even though he did not use the word type. True enough, but this

“ Stephens, Cat. Brit. Lep. 22, 1850.

Scudder, Historical Sketch 228, 1875.

Banks, N., and Caudell, A. N., The Entomological Code, 1912.

Lamarck, Syst. An. sans Vert., 1801.

Latreille, Consid. Gen., 1810.

SOME PROBLEMS OF TAXONOMY

303

is the very point on which it is necessary to have some authority
such as the rules for a dependable common basis. The trouble
through all the years has been just that which is made by these
objections , namely that every systematist has some favorite opin-
ion to which he holds like grim death in the face of all opposition.
Perhaps the writer too has favorite theories, and is championing
them as radically by supporting the International Rules, but
since this support occasions some extreme modifications of his
own wishes in the matter of nomenclature, it can hardly be
classed with the opinions here mentioned.

The desire to make exceptions is also displayed by even so
great an authority as Dr. Handlirsch.-' In his considerations of
“Nomenklatur, Typen und Zitate,’' this writer formulates a series
of rules of nomenclature drawn from various sources. He uses
the International Rules for the fixation of genotypes, but in con-
nection with his rule eight on priority, taken from the same
source, proposes the following exceptions: ''Ausgenommen von
Umstossung auf Grund der Prioritatsregel sind nur solche Na-
men die ganz allgemein bekannt und in vielen Hand — und Lehr-
buchern eingeburgert oder niedizinisch, technisch bzw. Okono-
misch von Bedeutung sind, sowie solche, auf Grund deren ein
allgemein gebrafichlicher Name hoherer Kategorien errichtet
wurde, so dass durch Ungultigkeitserklarung des einen Namens
auch die anderen umgestossen werden mfissten.’’ This is a com-
ponent of the International Botanical Rules. It seems utterly
impossible for such a rule to produce a uniform result in the
hands of all systematists. Who shall say what degree of familiar-
ity constitutes this right to stand? Moreover, what if a few
usages do have to be changed? Many now common were made
to supplant others of a more logical nature years ago, when the
older usages had stood for decades. For example, comma was
cited as the type of Hesperia by Dalman in 1816 (fidx ScudderJ,
and the genus was used in this sense by competent writers as
late as 1883, only to be removed at last to the place which it has
since occupied with malvae as the accepted type.

As the International Rules stand, they are a satisfactory work-
ing basis for the stabilization of nomenclature, and should not
be radically changed. By denying the use of the so-called re-
strictions, and by accepting as the type of a genus the first species

Schroder, Handbuch der Entomologie iii, 83, 1913.

304

A. W. LINDSEY

actually designated by the word type or an equivalent of un-
mistakable meaning, whether or not it is already the type of an-
other genus, they make it possible to eliminate much historical
work in fixing genotypes, and to arrive at a definite result with
the greatest possible degree of certainty that no pertinent matter
has been overlooked. The chief source of trouble in the rules
seems to be the arbitrary limitation of valid type fixations to
those in which the word type is used. Some argue that in French
this word does not have the same meaning as in English, but ac-
cording to all available dictionaries it has the proper meaning,
am.ong others, even as in English it may mean only a representa-
tive. Any objection to the use of these rules, however, is weak.
Its purpose must ever be the preservation of some familiar use
of terms, and no system can he applied to zoological nomenclature
as a whole which will not overthrow some such usage. Moreover
some arbitrary rule is necessary, advanced and supported by au-
thority, to override the multitude of personal opinions which will
otherwise never find a common ground. Nomenclatorial re-
search is a fascinating pursuit, but it cannot be said to advance
scientific knowledge an inch. It should be settled definitely for
all time, and the writer does not hesitate to express his opinion
that those who oppose the use of the International Rules are act-
ing selfishly and against the interests of the science which they
pretend to serve.

I feel these things very deeply. In common with many other
systematists, I have spent a considerable amount of time during
five or more years to reduce the described genera of my favorite
group to a definite basis. In view of some correspondence which
has reached me recently and has brought my interest in the mat-
ter up to its present pitch, I cannot but feel that such efforts
are, at least for the present, wasted. These genera have never
been consistently worked over. It would be relatively simple to
fix the type of each by the International Rules, but what would be
gained if Richard Roe should insist that he could not accept cer-
tain results, and John Doe that certain others are against his
beliefs? The result does not hinder their work, for in order to
object intelligently they must understand all phases of the points
involved. The greatest difficulty accrues to those who are not
students of nomenclature, perhaps even indifferent systematists.
In other words, by insisting upon points of personal opinion in
matters which are not vital, the systematist hinders him whom he

SOME PROBLEMS OF TAXONOMY

305

would help, to whom a real and conclusive stabilization of nomen-
clature would be invaluable.

We have the International Rules. They are clear and appli-
cable, and with the settlement of European difficulties it should
be possible to arbitrate properly the few doubtful points which
may arise. Why should not everv systematist suppress his per-
sonal desires, accept the few changes which result from the use
of the rules, and establish for all time this important, but none
the less accessory, framework of science?

Note: This paper was written in the winter of 1921-22, revised and
placed essentially in its present form in the Fall of 1922, and brought out
again in the early Spring of 1924, On the eve of its publication the writer’s
attention was caught by an article by Professor E. B. Babcock,^ a botanist,
in which reference was made to Hall and Clements’ “Phylogenetic Method in
Taxonomy,”'® The striking degree of agreement between the views ex-
pressed in the latter paper and in the preceding pages, where they touch
upon the same subjects, is such as to compel its mention here. It seems that
both botanists and zoologists are agreed upon the requirements of this
branch of science, and we may hope that the future will extend the valuable
renovation of methods which the present has begun.

Babcock, E. B., Genetics and Plant Taxonomy, Science LIX, 327, 1924.
Hall, H. M. and Clements, F. E., The Phylogenetic Method in Taxonomy,
Carnegie Inst, of Washington, Publication No. 326, 1923.

NOTES ON THE GEOLOGY OF GILES COUNTY, VIRGINIA
By *George D. Hubbard and fCAREY G. Croneis

INTRODUCTION

Location and Extent of Area

Giles County is in the northern section of the southwestern
portion of the State of Virginia. It is bounded on the north by
the State of West Virginia, on the east by Craig County, on
the south by Montgomery and Pulaski counties, and on the west
by Bland County. Pearisburg, the county seat, which lies a lit-
tle north and west of the geographical center, is 37°19'N latitude
and 80°44"W longitude.

Inclosed within the irregular boundaries of the county are a
trifle less than 350 square miles.

Previous Work

In 1881, Boyd^ published his ''Resources of Southwest Vir-
ginia,” which contained, among other things, a short account of
the geology of Giles County. Boyd, however, had merely sum-
marized the also short account which appeared in W. B. Roger's
"Geology of the Virginias” in 1841. The work, excellent for
having been done in the early forties, was not so good forty years
later. Boyd also gives a rather complete account of the county's
mineral resources. Here it may be said that Mr. Boyd was an
optimist when he was discussing the iron ores of Giles County.
However, it should be added that he was also something of a
prophet when he was discussing manganese prospects. Of this
more will be said in the chapter on Economic Resources.

Stevenson,^ in 1887, made a geological reconnaissance of a
half a dozen counties in the southwest portion of Virginia. Giles
was one of the counties visited and Stevenson’s observations on

* Department of Geology, Oberlin College.

t Department of Geology, University of Arkansas.

^ Boyd, C. R., “Resources of Southwest Virginia,” J. Wiley & Sons, 1881.

^ Stevenson, J. J., “A Geological Reconnaissance of Bland, Giles, Wythe
and portions of Pulaski and Montgomery Counties of Virginia.” Proc. of
Amer. Phil. Soc., Vol. 24, 1887.

307

308

HUBBARD AND CRONEIS

it were very good, considering the short time spent in the area.
To quote the author, “Tlie examination of the area under con-
sideration was purely a reconnaissance, and the notes in several
localities must be regarded as tittle more than suggestions to
the one who may make the detailed study on behalf of the U. S.
G. S.” Stevenson, who was at the time Professor of Geology at
the College of the City of New York, was a keen observer, and
his work is not without value even today. A geological map
accompanying the report, while recognizing but few divisions,
is fairly accurate over wide areas.

In addition to the above mentioned work, the U. S. G. S. in
1884-7 made a reconnaissance map of the Dublin, Virginia-West
Virginia quadrangle, in which is contained the greater part of
Giles County. On this map, elevations are found to be very
good, but no depression contour appears on the Dublin sheet,
although there are many sinks in the county whose depth is close
to 150 feet. However, everything considered, this topographic
map is extraordinarily good for reconnaissance work. It was
used, with corrections and modernization, as the base for the
geologic map accompanying this report.

In 1907, Watson^ published his “Mineral Resources of Vir-
ginia,” which mentions the iron mines of the county, as well as
the possibilities for the manufacture of cement.

Two years later, in 1909, there appeared Bassler’s^ “Cement
Resources of Virginia.” In this volume the stratigraphy of
southwest Virginia is worked out in some detail. Giles County
receives its share of attention, but post-Ordovician formations
here, as elsewhere in the work, are slighted since they are not
potential cement horizons. However, the writers have found this
bulletin to be the very best of any of the meager sources of
information on the Geology of Giles County.

Stose and Miser,^ in their bulletin on the “Manganese Deposits
of Western Virginia,” which was published in 1922, give a com-
plete account of the prospects in the county under discussion.
Physiographic forms, stratigraphy, and geography of western

^ Watson, T. L., “Mineral Resources of Virginia,” Jamestown Exposi-
tion Commission, 1907.

^ Bassler, R. S., “Cement Resources of Virginia,” Bulletin 2A of the
Virginia Geol. Survey, 1909.

® Stose, G. W. and Miser, H. D., “Manganese Deposits of Western Vir-
ginia,” Bulletin 23 of the Virginia Geol. Survey, 1922.

' GEOLOGY OF GILES COUNTY, VIRGINIA 309

Virginia are also discussed briefly in this bulletin, which has been
used rather freely by the writers.

The above list completes the published references to the
geology of Giles County. In addition, however, Watson has pub-
lished a geological map of the state of Virginia. The geology of
Giles County, on this map, is simply represented by five large
divisions, whose boundaries are not extremely accurate.

METHOD OF WORK AND ACKNOWLEDGMENTS

Field parties of students gathered from various colleges and
universities have for some time worked in this region as a part
of the Oberlin College Summer Session. The work was started in
1908 in Bland County and since that date nine other parties have
studied in the region, and eight of these in Giles County itself.
The camp from which the work was done has been each year in
a new place so that a considerable part of the county has now
been worked. Over 75 students have contributed to the
solution of the geologic problems of the area. During each of
these years a portion of the geologic section has been measured
and described in detail, and this description has been handed on
to the next class, so that a considerable heritage has accumulated.

In like manner collections of rocks and fossils have been made
and added to the collections of former classes. Lists of char-
acteristic fossils have thus been built up for several formations
and for a larger number of members. No publications have ever
come from this work but there is now a large body of data avail-
able for detailed study. It is hoped to put this material into
shape for publication as special papers or topical studies, but
first there seemed to be need for a general paper covering some
such unit area as a county. Hence this paper has been prepared.

The sections recorded in the body of this paper are the accumu-
lations of the several summers of work. Only a small percent
was actually measured and described in any one year. Credit is
due each class for its contribution to the whole. Credit should
also be given Messrs. E. R. Smith of De Pauw University and
C. W. Honess of Oklahoma University for special work on the
fossils. They have spent a second summer collecting and have
given much time to the study and identification of the various
forms collected.

310

HUBBARD AND CRONEIS

TOPOGRAPHY

Physiographic Location

The State of Virginia is divided into three physiographic pro-
vinces,* which are named, from east to west, the Coastal Plain,
the Piedmont Plateau, and the Appalachian Mountain divisions.
The last named province is again divided into the Blue Ridge,
Great Valley, and Alleghany Ridge regions. Giles County is in-
cluded in the last named, or westernmost, of these divisions. The
irregular valleys and ridges of Flat Top Mountain area are, how-
ever, more characteristic of the Cumberland Plateau region than
of the Alleghany subdivision. On the other hand. East River,
Wolf Creek, Sugar Run, Little and Big Walker mountains are
typical zigzag or parallel eminences of the true Alleghany Ridges,
defended by a strong sandstone.

Peters and East River mountains are the first westernmost
ridges and mark the initial sharp upturning of the strata.
To the northwest from these ranges is the much dissected,
mature Alleghany Plateau region whose strata are nearly hori-
zontal or very slightly flexed, but contain no true folds. How-
ever, a little south of the point where the New River enters West
Virginia, the pronounced folding begins and, in a short distance,
indeed in one formation (the Hinton) , the dip increases from the
horizontal to past the vertical.

Relief and Drainage

The central portion of Giles County is a broad lowland, wherein
flows New River, the master stream of the area. The western
portion of the county is made up of irregular ridges and inter-
montane valleys. The eastern portion is much the same, except
for the fact that the mountains here are consistently some 500
feet higher than those on the west. On the north, except where

* Hayes, C. W., The Southern Appalachians. Nat. Geog. Mon. 1895,
pp. 305-36.

Willis, Bailey, The Northern Appalachians. Nat. Geog. Mon. 1895, pp.
169-202.

Hayes, C. W. and Campbell, M. R., Geomorphology of S. Appalachians.
Nat. Geog. Mon. 1894. pp. 63-126.

Bascom, F., Cycles of Erosion in Piedmont Province of Pennsylvania.
Jour. Geol. vol. 29, pp, 540-559.

Campbell, R., Clapp, F. G. and Butts, Chas. U. S. G. S. Folio 189.

Shaw, E. W., Bull. G. S. A. vol. 28. p. 128.

GEOLOGY OF GILES COUNTY, VIRGINIA

311

the small projection of Giles County extends into West Virginia,
there is a natural boundary in the East River — Peters Mountain
range, which is a somewhat uniform ridge approximately 3500
feet in height.

The southern boundary is^ in the same manner, defined by a
ridge running parallel to the mountains described above. This is
the Walker-Gap Mountain range which is from 500 to 1000 feet
lower than the East River — Peters range. A distance of 12 miles,
on the average, separates the two ridges.

The highest point in the County is Bald Knob, in the east-
central mountain region, whose elevation is 4,348 feet. The
point where New River enters West Virginia has, of course, the
minimum height, which is 1472 feet. Giles County, then, pre-
sents a maximum relief of 2876 feet.

Johns Creek, a tributary of the James River, has its source on
the upper eastern slopes of Salt Pond Mountain. The extreme
eastern portion of the county, then, drains into the Atlantic by
way of James River. The divide between the streams flowing to
the Atlantic and those tributary to the Mississippi system, may
be drawn in Giles County along the crest of Salt Pond and Johns
Creek mountains. This entire basin, however, does not com-
prise more than eight square miles so that, for practical purposes,
it might be said that the county was drained by New River and
its tributaries.

New River rises near Blowing Rock, N. C., and flows northeast
to Radford, Virginia, a distance of about 100 miles. Here, it
turns to the northwest and cuts through the mountains of Vir-
ginia and West Virginia to join the Ohio at Point Pleasant
where it is called the Kanawha (as it is throughout its lower
course). This system is, of course, antecedent to the uplifts and
crustal movements which developed the Peters and Walker
mountains. In fact, New River is the only one which has, in
the Appalachians, preserved its Cretaceous or pre-Cretaceous
course to the westward. This has been due, in large part at least,
to differential warping which raised the headwaters so high that
enough gradient was developed to enable the river to cut through
the hard sandstones of the Walker and Peters ridges. These
were elevated with the rest of the region, but slowly enough so
that the river could maintain its course in spite of the elevation.

From Angels Rest, or Bald Knob, New River Valley looks

312

HUBBARD AND CRONEIS

much like a great amphitheatre, which is walled in at all sides
except where the stream enters and leaves the county. The en-
trance is by way of a narrow valley which is cut across the
Walker-Gap Mountain ridge. The exit is by a similar valley,
even more restricted, cut in the East River-Peters Mountain
system. The principal tributaries to the New in Giles County
are Walker, Wolf, and Sinking creeks. All of these streams,
however, have their sources outside the county. East River,
which has its headwaters in Virginia, flows, through most of its
course, in West Virginia only to enter the New by way of Giles
County. However, since it flows less than a mile in the County,
the portion it drains is neglible.

The relative absence of small tributaries is a feature which is
apparent at once. Streams which are carrying considerable
water in their upper valleys are much restricted in size, when
they enter the limestone area adjacent to the New River. This
is due to the large amount of drainage which is under ground in
Giles County, and of which more will be said tater.

Erosion Cycles

In Giles County, the elevation of the highest peneplain cannot
be determined accurately because, having suffered the most from
erosion, few of its remnants remain. In spite of this fact, Doe
Mountain, Pearis Mountain, Angels Rest, and portions of the
crest line of Peters and East River mountains have a fairly
uniform height of 3500 feet. This elevation represents a former
peneplain surface, which probably was completed in late Jurassic
time. In this paper, this peneplain will be referred to as the
Pearis Peneplain.f Above this early plain, which was then close
to sea level there rose monadnocks to the height of 200 to 800
feet. Today Bald Knob, Butt Mountain, and portions of Sugar
Run Mountain remain as remnants of these former elevations.

t Correlation in this paper is with Stose and Miser, who have given us
one of the latest interpretations. It should be borne in mind that they
assign earlier dates to most of the erosion plains than do Willis, Campbell
and others; and also that Shaw has ascribed later dates than the older
workers. In order to determine the dates of these peneplains it is neces-
sary to trace them eastward and southward where they disappear under
sediments of the Coastal Plain. Our work has never allowed us to carry
forward such tracing hence we probably should not commit ourselves at
all, and thus our correlations with the work of others in the Valley of Vir-
ginia and with Willis in the Northern Appalachians must be looked upon as
provisional.

GEOLOGY OF GILES COUNTY, VIRGINIA

313

Brushy and Spruce Run mountains, as well as portions of
Walker, Peters and Flat Top mountains have a height of approx-
imately 3100 feet. This is the probable elevation representing a
second base level which was only partially completed in Cretace-
ous time. This old base level will be referred to as the Spruce
Run Peneplain.

A third and still less extensive base level was partially reached
in early Tertiary time (probably late Eocene). This old surface
is represented by heights in Buckeye Mountain, and by numerous
spurs on all the mountains having the uniform height of about
2500 feet. This base level will be called the ‘‘Buckeye Peneplain''
in this report.

A fourth, and last base level, which was in all probability
reached in late Tertiary time, is represented by the numerous
elevations in Giles County of approximately 2100 feet. This
valley floor peneplain will be referred to as the “Pearisburg"
base level. Remnants of this old surface are better developed
in Monroe County to the north than they are in Giles, however,
much of the land about Pearisburg and at various points along
New River stand at this elevation. On this level are quantities
of gravel, sands and clays of fluviatile origin.

In latest Tertiary and in Quaternary time. New River has cut
its present gorge in this area. Work towards the ultimate base
level has scarce begun, yet the valley has been incised at least
400 feet. In the future, lateral planation will exceed vertical
cutting in this county, because the New River is regulated by
the natural quartzite dam across its valley at the Narrows. This
resistant rock can be cut only very slowly, so that above the
Narrows the limestone valley probably will continue to broaden
rather rapidly.

The peneplain surfaces in Giles County are not so well deflned
as they might be, yet it is possible to make a rough correlation
of the base levels recognized here with those described by Stose
and Miser® as occurring in the Valley of Virginia.

The Upper peneplain at 3500 feet is undoubtedly the same as
the Summit Peneplain of Stose and Miser, at an elevation of
3000-3800 feet. This base level is regarded as older than the
Kittatinny peneplain of Pennsylvania. The Spruce Run pene-

® Stose, G. W., and Miser, H. D., Va. Geol. Surv. Bull. 23. “Manganese
Deposits of Western Virginia,” 1922. pp. 20-22.

314

HUBBARD AND CRONEIS

plain corresponds roughly to the Upland peneplain of Stose and
the Kittatinny peneplain. The elevations grade from 3100 feet
in Virginia to less than 2000 feet in Pennsylvania. The Inter-
mediate peneplain, as described by Stose, is in Giles County
developed as the Buckeye Peneplain, which here is some 250 feet
higher than farther east. The Valley-floor base level of Stose, is
the Pearisburg Peneplain of Giles County. Here it is 100-200
feet higher than it is to the east in the Valley of Virginia.

Since Jurassic time it is evident that Giles County has been
elevated some 3000 feet. The most widespread peneplain was
the first. The later ones were successively smaller and more in-
complete. The present drainage is about 1500 feet above sea
level. A peneplain this far from the sea would probably stand
300-400 feet above sea level.

Underground Drainage

A very prominent feature of this area is the sink hole topog-
raphy. As has been mentioned before, the U. S. G. S. map of
1884 does not indicate any depression contours. However, these
sinks develop with considerable rapidity, some of the older natives
recalling a half a dozen of ordinary size which have appeared
during their life time. The writers do not from this intend to
convey the idea that the sinks were too small to be mapped in
1884. Their omission from maps of this issue is regarded as
the result of the reconnaissance nature of the mapping, or to
the fact that, at that date, no depression contours were used on
any maps.

Sinks are confined to the limestone areas of Giles County.
So common are they, that they can be of use in determining the
outcrop of the Shenandoah and Chickamauga formations, to
which horizons they are limited. Caves are invariably found at
the bottom of the sinks. The latter have been formed by the
falling in of the roofs of solution passages, which ordinarily
have formed along joint plains. Some of the caves are so ex-
tensive that it is possible to travel many hundreds of yards
through their various passages.

In many cases, the surface drainage is in the reverse direction
of the underground, so that when an entire series of sinks
develop along prolonged joint planes (as they often do), the
surface drainage is reversed. As a result of this underground

GEOLOGY OF GILES COUNTY, VIRGINIA

315

type of drainage, many great springs are found bordering the
New River, and small tributaries are uncommon in the limestone
areas. The New, itself, seems to vary greatly in size over
small areas. The writers believe that this is due to the fact that,
some of its water, at places, flows underground or in crevices for
a distance, only to join the surface waters of New River again
in the form of great springs, some of which may be hidden but
many of which are visible. Of course solution topography and
underground waterways could not be developed much below the
water table.

No typical karst topography has developed in Giles County,
but the sink hole areas are usuafly turned into grazing lands
since the soil mantle is too thin to be easily cultivated.

STRATIGRAPHIC GEOLOGY
INTRODUCTION

In Professor W. B. Rogers’ classification of the geological
formations appearing west of the Blue Ridge in Virginia, four-
teen groups of strata were given numbers, beginning with the
oldest. His brother. Professor H. D. Rogers, divided the Paleo-
zoic rocks of Pennsylvania into fifteen sets, “extending from the
deposits which witnessed the very dawn of life upon the globe,
to those which saw the close of the long American Paleozoic
day.” Thus the names of these formations were the various
parts of the day, instead of the ordinary geographic terms used.
Extremes, then, of his classification were Primal, signifying the
dawn (that is, tower Cambrian), and Serai, meaning night (and
corresponding to the coal-measures.) In the literature of Vir-
ginia, both systems have been used. A table is introduced here
to show the relation between these classifications and the one
now in use.

The rocks of Giles County comprise all of the divisions of the
Paleozoic from lower Cambrian to the lower Carboniferous in-
clusive, No younger consolidated strata are found, but some
Tertiary gravels are present, which may be the approximate
equivalent of the so called “Orange Sand” found in the. states
further west. Limestones are quantitatively in predominance
in Giles County, being especially well developed in the older Pal-
eozoic divisions. Besides limestones, there are shales, cherts,

CORRELATION TABLE OF GEOLOGIC FORMATIONS OF WESTERN VIRGINIA

316

HUBBARD AND CRONEIS

.2

1 1

o; -4-3

a

Ph,

fH O)
rP a

s ^

•+J -(J

P <x> c

<D b£j OJ
C PPS
O <1> c3
flH>0

^ s

1I

P-I ^

P O) P

^ &c ^

03 p >
O P O)

CQCOhP

oS p P

.S.S O

"p "p ^

?-l ^ TO

OOP
?H ^ p

<<CU

I— < m

w 0)

PrP

« s

-I

Ti +3

p ^

«a

o

> >

>nHH

t-H t-H h-(

X

HH

G

> >

>>S

<D O

a ^

o

a

a

o

Vi

a»

o

• ^
oi^ o

V^ V

o o

S:2|

;^Sh3

G

s

h-1

pSJ

^ ,

GEOLOGY OF GILES COUNTY, VIRGINIA

317

conglomerates, breccias and sandstones. The latter are some-
times metamorphosed partially into semi-quartzitic divisions.

Most of the ridges are capped by the Clinch sandstone, which
is a very resistant division of the Silurian, while the valley floor
is usually the Shenandoah Limestone. Outcrops are often de-
creased or made wider by the complex folding and faulting.

On the following page is a table of the formations found in
Giles County.

THE CAMBRIAN SYSTEM

Introduction

The Cambrian of Giles County is made up of limestones and
shales in the lowest division, and of limestone and dolomite in
the upper portions. The Middle Cambrian time seems to have
been one of erosion in this area, although the unconformity be-
tween the Lower Cambrian Russell and the Upper Cambrian
Shenandoah is not marked. Deposition was continuous from
Upper Cambrian on into Ordovician time, hence the great Cam-
bro-Ordovician limestone series.

The Russell Formation

The Russell Formation, composed of variegated shales, massive
and impure limestones, takes its name from Russell County, Vir-
ginia, where it is found developed to its fullest extent. It is
probably equivalent to Apison and Rome formations of Southern
Tennessee.

In the Pearisburg section, it is brought in over a small area
running with slight variation east and west through Bane, by
the large anticline between Pearis and Walker mountains. In
this exposure, it is non-fossiliferous but in some localities* it
carries the Olenellus fauna of Lower Cambrian time. The forma-
tion passes from medium bedded, resistant, blue gray, blotched,
limestone at the base, through highly colored green and choco-
late shales and intermediate limestone lenses and layers, to
greenish and yellow shales, which, in some places, grade directly
over into the Shenandoah formation but in other places are
separated from it by several feet of white and gray calcareous
shales.

Four small anticlines, the largest of which is approximately

* Russell County, Virginia.

NAMES OF FORMATIONS

318

HUBBARD AND CRONEIS

X/l

U

(V

bfl

o

o

a

CD

o ^

OCC
-M cu

.S ^

o

X!

>>>>>

biO <D ^ 3

O 0)

.rH 3 bic c« ±:

M E +-> 2; S ^
4J 0) C S S
ccs^ O

OOPnOffiS

rC

m

bJD

• S

OJ

0)

C

S

o

bJO

0)

?H

0)

2

"o)

&«

cd ^

^ D
.2 ^
^ o
O J

>>

bJC

?-i

D

.Q

f-l

0)

2

&W

cd s_i

CD

2 ^

?H o

o

N “
cd >
^ 0)

OhJ

s

p

o

o

>5

(D

s

o

b£

4J

s

o

>5

sg w

2 S

p p

be M

OT

> cd
P

Oi p

P o

tJ o
0)

s ^

M 8

2 'S)

S 2

rh O
^ 0)
0) O

H <<

• GEOLOGY OF GILES COUNTY, VIRGINIA

319

1000 feet across, and numerous structures of a few feet each,
mark the crest of the larger anticline and make measurements
to determine the thickness of the Russell Formation highly un-
satisfactory. The thickness, however, cannot be less than 300
nor more than 400 feet.

The formation clearly marks a transition period which may
have introduced the time of erosion correlated with the lack of
Middle Cambrian, and directly preceding the time of deeper seas
prevalent during the formation of the Shenandoah Limestone.
That the formation is a weak one is clearly shown by the num-
erous folds throughout the entire thickness, some of which do not
appear at all in the adjacent Shenandoah. It disintigrates rap-
idly into a soil which is not as fertile as that resulting from the
decomposition of the Chickamauga and Shenandoah Formations.

The Russell Formation Subdivided"

X. At the base of the Russell formation is a medium even-
bedded limestone exposed along Walker Creek below Bane. It
resembles the Shenandoah in some of its characteristics and is
very different from the usual Russell. It runs under the typical
Russell and is obviously older, but since its base is not exposed it
may be a lens with more typical Russell underneath. For this
reason this division is here called x and grouped under the head-
ing of Russell. The color is blue to gray with red and purple
lines and blotches which give the member a purple tinge. It is
very hard and resistant because it is in part siliceous. Very fine
crystalline to dense with weak irregular jointing. There are
many branching calcite veins which are thin and thread-like in
appearance. No chert nor fossils seen. Weathers dirty blue and
black, rarely light blue. In the stream the red lines and blotches
are emphasized by weathering so that the entire rock appears
red. It is a ripple maker in the stream.

Thickness 80-100 feet +

1. CHOCOLATE, GREEN, AND BLUE SHALES

Medium to thick bedded shales with prominent cross-bedding
and jointing in all directions. There are a few master joints.
There are also sandstone and limestone lenses, the latter of which
are dense blue layers six inches to two feet in thickness and

’ In all the subdivisions, the numbering is from the bottom up.

320

HUBBARD AND CRONEIS

many feet in breadth. The colors grade into each other both
vertically and horizontally. Great blotches of green or red are
common. Weathers rusty brown to black. Nb fossils were seen.

About 150 feet.

2. CALCAREOUS SHALES AND LIMESTONES
(THE MIDDLE LIME)

This division is thin bedded for the most part but there is one
layer about eighteen inches in thickness. In general, the colors
are buff to blue in the limestones, and green to brown in the
shales, the entire formation weathering a dark brown, except a
light blue 4 inch limestone layer which becomes yellow to white.
In some places, it is paper bedded; blue with delicate yellow
layers alternating. There are calcite veins, and in a limestone
lense-like layer, there are cavities partially filled with calcite
crystals.

From 10 to 30 feet.

3. GREEN AND YELLOW SHALES

Calcareous to sandy, thin, red layers occur. The formation is
thin bedded, and rather regularly jointed so as to break into
blocks. Weathers yellow and brown and disintegrates more rap-
idly than division number one.

About 50 feet.

4. BLACK AND GRAY SHALES

These occur locally below the Shenandoah and probably belong
to the Russell formation. The colors are black, gray to nearly
white, weathering a dirty black to mud color. These shales are
dry, fissile and non-fossiliferous. They may be erosion remnants.

Thickness 0-10 feet.

Besides the exposure at Bane, the Russell outcrops about a
half mile farther down Walker Creek and is also exposed over a
very limited area at the Norfolk and Western Railroad cut near
Goodwins Ferry. (Not shown on the map)

Bassler® believes that the formation has a thickness of at least
a thousand feet in the vicinity of Clinchport, Virginia. He says,
“Although the major portion of the formation is of little value
from an economic standpoint, the argillaceous shales of the upper
division may prove of use for mixture with pure limestones in

® Bassler, R.'S. “Cement Resources of Virginia”, pp. 148.

GEOLOGY OF GILES COUNTY, VIRGINIA

321

the manufacture of cement/' However, the great range in the
composition of these shales as indicated by the following analysis,
should lessen the possibilities in this respect.

ANALYSIS OF THE RUSSELL SHALES
Vicinity of Clinchport
(J. H. Gibboney, Analyst)

1

2

Insoluble

.. 41.72

89.52

Alumina and iron oxide

.. 5.68

7.22

Lime

... 17.32

0.42

Calcium carbonate

.. 30.93

0.72

Magnesia

... 9.17

1.05

Magnesium carbonate

... 19.29

2.21

While these analyses were made from samples of the Russell
formation from a different area than the one under considera-
tion, they may serve to give spme conception of the composition
of these shales in Giles County.

This is the first time that the Russell has been reported from
Giles County, the reason being that the formation weathers so
rapidly that it quickly covers itself up. The exposures noted
above were first found in recent road or railroad cuts.

CAMBRO-ORDOVICIAN

The Shenandoah Limestone

The Shenandoah Limestone is a heavy bedded, gray blue, dolo-
mitic, limestone near the top, grading downwards into a darker
more sandy limestone at its base. It takes its name from the
Shenandoah Valley where it outcrops very extensively. There is
a breccia at its base in some places whose fragments are made
up of bits of shales from the older Russell formation. In other
localities, this formation has been subdivided into or corresponds
with the Honaker Formation, the Knox Dolomite, and the Noli-
chucky Shales. It probably corresponds, except for the upper
portions, with the Beckett Gneiss of New England, the Potsdam
Sandstone in New York, and the Stissing Slates, all of the Upper
Cambrian. However, Beekmantown, and even Trenton fossils
are occasionally found in the uppermost layers.

This limestone has a thickness of at least 5000 feet at places

322

HUBBARD AND CRONEIS

and includes many shale and sandy lenses and partings. It is for
the most part rather heavy bedded and dense, but includes such
wide variations in its great thickness that it is hard to gen-
eralize. It carries a large amount of chert in lenses and in
nodules, the chert being both light and black, but the light is in
great preponderance and the black occurs only in the lower
layers.

The formation is for the most part calcite veined, with calcite
nodules and calcite-filled cavities numerous. Pyrite occurs in the
shape of pyritohedrons, and limonite and hematite pseudomorphs
after these crystals are not uncommon. Fossils are uncommon in
the limestone but a few gastropods occur as well as other fossils
too fragmentary to be recognized. However, in some places the
chert is quite fossiliferous and gastropods, brachiopods, and
sponges can be identified.

The rock usually weathers light and has an uneven to conchoi-
dal fracture. Many layers are wave marked. The jointing is as a
rule not pronounced; however, it is so good in the county road
cut along Walker Creek between Bane and Staffordsville, that the
joint planes are with difficulty distinguished from the bedding
planes. Practically all the valley floors are made up of Shenan-
doah Limestone, and the white chert remaining after the lime-
stone has disintegrated is found widely scattered.

The limestone is quarried in several places in this region and
is used extensively for ballasting, for lime making and for build-
ing purposes. The soil resulting from its disintegration is rich
and productive.

The Shenandoah Subdivided

Section along the Virginian Railroad cut at
the Narrows of the New River

1. Gray blue, fine grained, rather massive limestone, with

shale partings of one to three inches. Flattened layers of black
chert and a few small calcite veins. The limestone layers are
from several inches to three feet in thickness. The formation
weathers light buff to white, losing all the blue. The fracture is
uneven to conchoidal with minor jointing vertical to the bedding
planes. No fossils seen. Dolomitic. 25 feet.

2. A gray blue, fine grained, massive limestone with no chert,
having, however, nodules and veins of calcite arranged in all

GEOLOGY OF GILES COUNTY, VIRGINIA

323

directions. The layers are two to six feet in thickness. About
six feet from the base, there is a two foot layer which is con-
siderably darker than the rest of the division. Weathers light
buff to white but does not bring out the bedding. The fracture
is conchoidal with coarse patterns. Joints are rare and small.
No fossils seen. Dolomitic. 20 feet.

3. Color as in one and two — fine grained, crackled and hackly,

siliceous limestone of 11 feet between a one foot layer of light
cherty limestone at the base and a blue cherty layer of two feet
at the top. Weathers black to buff. No fossils seen. No calcite
veins and no chert in the middle portion. 14 feet.

4. Gray crystalline limestone layer with no apparent bedding.

No chert. Joints intersect in all directions giving angular blocks
of small size. Calcite nodules numerous and a little calcite along
the joints. Weathers dark. No fossils seen. 10 feet.

5. Light siliceous limestone with veins and small nodules of
calcite, also of quartz, and the entire division is sprinkled with
quartz grains. This division is conspicuous as a light band
across the face of the cliff as it weathers very light. There are
disconnected delicate pink threads shot throughout the layer.

3 feet.

6. Dove colored, fine grained, dense, siliceous limestone with
inconspicuous bedding. No chert, but with numerous calcite
veins, some of which are in the joint planes. Calcite nodules and
crystals give this division a mottled appearance. No fossils seen.

7 feet.

7. Bluish, massive, cherty, crystalline limestone, with round

quartz veins and fragments of chert and chalcedony. The bed-
ding is not apparent. Weathers brownish with ferruginous
blotches. Crystals of light and dark calcite give a pronounced
mottled appearance to some layers. Coarse, hackly fracture and
little jointing; no fossils. 31 feet.

8. Bluish gray to drab, dense, fine grained, crystalline, un-
even bedded limestone with calcite veins and bunches of calcite
crystals. Fractures and weathers as No. 7. Joints are rare but
when they do occur they are in all directions. This division
seems to be a leveling up layer on a surface of marine erosion.

4 to 8 feet.

9. Medium to coarse crystalline limestone, light gray in color.
Distinct layers of light chert are numerous towards the bottom.

324

HUBBARD AND CRONEIS

Some of this chert is translucent. Minor joints at various angles
developed by weathering. Calcite veins are numerous and minute
and form a network through the member, which weathers red
and brown. 24 feet.

10. Similar to No. 9 but darker, thinner bedded, and more

coarsely crystalline. Wave marks are pronounced about two feet
and a half from the top. 9 feet.

Note: Small faults of 10 inches and 2 feet respectively below
and above No. 10. Numbers 9 and 10 constitute a rather mashed
zone.

11. Dove colored and pink mottled limestone, much jointed into

small cuboidal pieces. Fine grained, felsitic with no chert. In-
conspicuous veins of hematite and limonite. 2 feet.

12^ Gray blue, massive, dense, fine crystalline limestone,
coarser towards the top. One heavy layer. Many heavy calcite
veins some as thick as a half an inch, at right angles to the
bedding planes. Traces of pink common in the lower parts.

6 feet.

13. One foot layer of coarsely crystalline limestone, greyish

blue in color. 1 foot.

14. Blue gray, fine crystalline limestone, which is rather

heavy bedded. There are three zones of chert nodules located
respectively at the top, middle, and base. The chert is both light
and dark. Calcite crystals occur in veins and in bunches. The
bedding is not distinct but there are many irregular joints.
Weathers a dirty brown. No fossils seen. 25 feet.

15. Bluish limestone in layers of two feet each, fine grained

and dense at the bottom, with coarse crystalline layer, ill defined
and of uneven thickness at the top. Calcite veins minute. Darker
than most of the units ; has siliceous black shale layers in which
are embedded fragments of a very different limestone. These
shales vary in thickness from a knife edge to five or six inches
and are crumpled in many places. Wave marks at the top. No
chert. Former small cavities in limestone are filled with calcite
crystals. 11 feet.

16. Single layer of light bluish limestone with conchoidal
fracture. No chert but much calcite veining, often more than a
half inch in thickness. Mostly fine grained, but with pieces of
coarse crystalline limestone and sandstone embedded in the layer.

61/2 feet.

GEOLOGY OF GILES COUNTY, VIRGINIA

325

17. Dark gray crystalline limestone, rather massive but with

bedding concealed. Many crooked joints running in all directions
developed by weathering. ' The lower six feet are coarser crystal-
line than the rest, with threads and knots of chert throughout,
calcite veins and bunches of crystals all through the member but
increasing towards the top, where a mottled appearance is de-
veloped. Some small shale lenses. Pyrite is present in cubes and
pyritohedrons, and there are pseudomorphs of limonite and hem-
atite after these crystals. Weathers dark to black with chert
and calcite in relief. 20 feet.

18. Color the same as in 17, but lower part has red streaks

and spots. A dense, finely crystalline, felsitic appearing lime-
stone in beds up to three feet in thickness. Several layers of
light colored chert lenses and nodules occur. Calcite veins in
places, with jointing rare and irregular. Weathers a rusty
brown, not black. Bryozoans at the base. 11 feet.

19. Limestone, a dove color below to red above with calcite

veins white to green and crystal lined cavities. Bedding is not
distinct. Upper part becomes crystalline and slightly arenaceous.
Veins are often not completely filled. Joints are irregular. No
chert. Weathers brown. 41/2 feet.

20. Thin red shale, thicker limestone, thicker red shale, and

six feet of sandy and shaly, red limestone constitute this unit. It
is capped by a few inches of shaly sandstone, which has reddish
and greenish streaks. No layers are constant, the shale is fissile
and ferruginous with inclusions of limestones. There is a layer
of chert nodules in the upper limestone. 9 feet.

21. Dark blue, compact, fine grained, even layered limestone,
mottled with light blotches of chert and calcite crystals. Joints
are very rare but the formation breaks into even blocks to make
good building stone. Weathers lighter but into a dirty brown.

3 feet.

22. Dark, red and green streaked, cross bedded sandstone, in
two or three layers. White quartz in knots and crystals. There
are also* crystals of calcite and pyrite and chert nodules.

1 foot.

23. Dark blue limestone layers of three inches tb three feet,
which is darker above. Weathers a dirty gray to buff. The upper
part has cavities lined with calcite and the entire unit has quartz

326

HUBBARD AND CRONEIS

lined cavities. There are red blotches on the surface due to
oxidized iron. 10 feet.

24. Interbedded black and white chert and shale layers, with
one irregular limestone layer about four inches in thickness.
The bedding is more distinct towards the bottom where jointing
becomes abundant. There are several waved surfaces. Calcite
veins and nodules with large pseudomorphs of limonite.

5 feet.

25. Several grayish, dense, limestone layers of less than two

feet each in thickness. The upper layers, on weathering, bring
out the thin bedding. There are also thin partings of light, cal-
careous shale. Joints are rare and irregular. Red blotches and
threads, with little calcite and no chert. Fossils seen about half
way up the unit. Limonite pseudomorphs. 11 feet.

26. Blue, heavy bedded, medium crystalline limestone with
definite layers and chert nodules. Some layers are siliceous but
not sandy ; the main beds, six in number, show minor beds on
weathering. There are several small shale partings and one fer-
ruginous, flinty parting which is cross-bedded. There is also a
one foot calcareous, shale layer seven feet from the top.

47 feet,

27. A faulted zone with slickensides common. Most definite
fault is the southern and has a dip of fault plane about 67°N 89°
W. Strike is therefore N 1° E. Two or more major faults
occur to the north of first one but the dip and strike and amount
of displacement are not determinable. This is a brecciated zone
of greatly smashed and distorted strata. Probably 103 feet.

28. (We are now on the wagon road, having been on the rail-

road up to this point) . Heavy bedded, bluish grey, finely crystal-
line limestone with layers and nodules of white and light blue
chert, some layers of which are 2 inches thick and single nodules
6 inches across. There is little jointing but there are calcite
bunches. The top of the unit is wave marked with crests three
feet apart, with a shaly parting at the surface. Weathers red
and rusty. 27 feet.

Wave markings and shale partings may mark change in con-
ditions and life, but there seems to be no change in dip or strike
and little change in the lithological phase of the rocks. The wave
marks and crests trend N 15 to 20 degrees E.

GEOLOGY OF GILES COUNTY, VIRGINIA

327

29. Grayish blue limestone layers above shale parting two

inches to three feet in thickness. Joints are vertical but not at
right angles to the bedding. Other joints give sharp angles.
There are calcite veins and a little chert. There are several
shale partings with cross bedding in the lower layers, but the
third layer is leveled up. Lower layers have conchoidal frac-
ture. Rock is fine grained to fine crystalline. Weathers to bring
out the bedding. 34 feet.

30. Group of gray to brownish thin layers of quartzitic sand-
stone, with shale below. 2 to 4 inches.

21. Blue to blue gray, fine grained siliceous limestone, with
much black and grey chert. One layer of the chert toward the
top is nearly continuous. The unit has a hackly fracture with
little jointing. Many calcite veins weather in relief. Weathers
buff, brown and black. ' 3^/2 feet.

32. Felsitic to fine crystalline massive, bluish, limestone be-
coming lighter above. Bedding is not clear but is developed by
weathering in the upper portion. In crystalline layers the cal-
cite weathers out and feels like sand on the surface. Calcite
veins weather in. Much black chert in layers of nodules. Joint
ing is rare. Top layer seems to be wave marked as well as others
and there are some thin shale partings on the wave marked sur-
faces. Weathers a reddish brown to nearly black. 24 feet.

33. Several limestone layers similar to 32 but thinner

bedded, capped by a thin bed of bluish to reddish shale a few
inches in thickness. In some places the shale contains chert and
limestone pebbles as if residual. 11 feet.

34. Series of broken limestone beds similar to 33 with three

small faults of a foot or so-. Solution work and a filled sink
hole are present. The filling is chert, clay and sandstone pebbles.
White chalcedonic chert in the lower part. There are two shale
partings near the top about a foot apart. 29 feet.

35. Gray, rather massive, uneven bedded, finely crystalline
limestone except three feet from the top where it is coarse.
There is a pink layer two to four feet from the bottom. There
are peculiar pits on the surface about six feet from the bottom.
Weathers lighter than the stone to buff, not red. Calcite veins
and nodules. Wave marks with a shaly surface at the base.

20 feet.

328

HUBBARD AND CRONEIS

36. Blue, finely crystalline to felsitic limestone becoming
lighter and more felsitic toward the top. Crystals of calcite
throughout the entire section. The chert is not noticeable above
the first ten feet. In this section, the rock is broken by the
growth of concretions, giving a brecciated appearance and con-
torted beds. There are good dip joints, others are irregular
and at various angles. Many of the layers are sandy. Pyrite,
limonite, and siderite show on the surface. Weathers dark and
differentially, emphasizing the chert in relief, and the calcite
along bedding planes in depressions. Beds vary from one to two
feet in thickness but there is one single bed of six feet.

53 feet.

37. Dark gray crystalline limestone which is nearly pure in

beds which are for the most part four to twelve inches in thick-
ness, but there is one bed of four feet near the bottom. There
are bunches of calcite crystals in the thick layer and there are
two chert layers, one at the top and the other three feet below.
The upper one is of neat rounded concretions with concentric
structure. Rock has conchoidal fracture. Weathers buff to
brown with large curved surfaces. 12 feet.

Nos. 37 and 38 are found both on wagon and R. R. cuts.

38. Light and dark gray felsitic limestone which looks flinty.

Conchoidal fracture. At the middle, there are two layers with
pits and knobs which fit together like waffle irons. There is a
little black shale along this bedding plane. Chert layers at the
base. Weathers dirty buff to brown. 12 feet.

No. 38-44 are all found on Virginian railroad cut.

39. Dark blue, medium bedded crystalline limestone with

some calcite veins. There are several shale partings near the
top. Red threads occur in the blue limestone. Dip joints are
the most pronounced but there are some others present. Near
the base there is one arenaceous blue layer. Weathers a dirty
brown with the veins weathering in. 25 feet.

40. Lower mottled layer with light and dark gray in bars

and blotches. Fine grained and crystalline with calcite bunches
showing clearly. The layers are six to twenty-six inches in
thickness, with three small shale partings. No conchoidal frac-
ture. Weathers a darker reddish brown. 10 feet.

41. Lower light steel gray layer of fine grained crystalline
limestone. Fracture slightly conchoidal. Beds are from 6 to 15

GEOLOGY OF GILES COUNTY, VIRGINIA

329

inches. Joints are rare. There are calcite nodules but no veins
and no chert. Fossils in a layer of thin black shale one foot below
the top of the horizon. Weathers lighter than the rock to yellow.

7 feet,

42. Upper, mottled layer with light and dark grey in lines,

bars and blotches. Crystalline and coarse grained more pro-
nounced grains than in the lower mottled layer. There are a
few calcite crystals and veins. No chert. Some oblique and
irregular joints. One layer only. 2% feet.

43. Upper, light steel gray layer of limestone. Fine crystal-

line with conchoidal fracture. The bedding planes are rarely
smooth, some being fluted or pitted like waffle irons. Calcite
veining in the joints, and there are shale partings between some
of the layers. Calcite crystals are common in the upper portion.
Two feet from the base there are quartz crystals, iron oxide and
an unidentified green mineral. Weathers light. Fossils were
found in this member in 1923 consisting of brachiopods, cephalo-
pods, a simple coral one inch in length and the pygidium of a
small trilobite. 11 feet.

44. Bluish to dark steel gray, massive but medium bedded
limestone whose layers are two inches to three feet thick. It is
crystalline and looks like chert but is quite free from it. Joints
are rare and the fracture is uneven to conchoidal. Calcite
crystals occur in nodules and a few veins. Weathers lighter than

the rock to yellow. 4 feet, 5 inches to 10 feet, 8 inches.

Total thickness 609 feet.

This division does not complete the Shenandoah, but it is as
final as can be made in this area. Unit 44 is just below the
Chickamauga but unit 1 is an undetermnable distance above the
top of the Russell.

THE ORDOVICIAN SYSTEM

Introduction

Ordovician rocks are widely distributed in Giles County, form-
ing parts of the valley floor and sometimes capping lower ridges.
The series grades from limestone at the base to sandstone at the
top, and shows a distinct graded transition; limesone to argil-
laceous lime to shale then to arenaceous shale, which gradek
further into shaly sand and at last becomes a distinct sandstone
in the Bays.

330

HUBBARD AND CRONEIS

The Chickamauga formation has the greatest economic value
of any formation in this system. It has enormous possibilities
as a cement horizon, can be used for road material or as a building
stone. In addition to these values, it distintegrates into a very
rich soil. The other formations of the Ordovician have little
economic importance.

The Chickamauga Formation

This formation takes its name from Chickamauga Creek in
Walker and Catoosa counties, Georgia, where it outcrops exten-
sively. The lower layers are usually composed of a chert breccia
which separates it from the Shenandoah, but where the breccia
is wanting the separation can be made where the light impure
limestone of the Shenandoah is replaced by the blue fossiliferous
beds of the Chickamauga.

The breccia mentioned above is in some places 50 feet in thick-
ness and varies from coarse at the base to fine at the top. The
breccia consists of chert and non-crystalline limestone frag-
ments in a crystalline limestone matrix. The chert fragments
are sometimes as large as 15 inches in their greatest dimension
and are always angular and lie in all positions in the matrix.
In some localities fragments of sandstone, vein quartz, and
quartzite occur along with the chert. This breccia seems to
occur in the same horizon as the Birmingham Breccia of Georgia
and Alabama, and like that stratum records uplift and erosion
somewhere not far distant.

The Chickamauga is usually a blue, flaggy limestone, heavier
bedded towards the base. It is sometimes separated from the
lower formation with difficulty; however, the base generally
carries large quantities of black chert which can be used as a
distinguishing feature since the upper Shenandoah contains only
light chert. The formation has a hackly fracture and usually
weathers blue with water worn rounded forms characteristic.
This limestone is more jointed and thinner bedded than the aver-
age Shenandoah. The calcite veining is also more prominent in
this formation than in the preceding one. The thickness varies
from 800 feet on East River Mountain to 700 feet on Big Walker
Mountain. At the Virginian Railroad cut at the Narrows 806
feet of Chickamauga is exposed.

The Chickamauga is the great marble producing formation of

GEOLOGY OF GILES COUNTY, VIRGINIA

331

the South, but in this locality, while there are a few small occur-
rences, it is a coarse grained, dull gray rock fit only for build-
ing purposes. Like the Shenandoah, this limestone disintegrates
into a rich soil, characteristic of such fertile spots as Burke’s
Garden and the Pearisburg areas. Unlike the underlying forma-
tion, however, the undesirable residual mantle of chert is not pro-
nounced. This formation has its greatest development near the
margin of the Appalachian Valley.

Paleontology and Correlation

The following is a list* of fossils found in the Chickamauga
formation of Giles County:

Tetradium fibratum
Constellaria sp.

Dalmanella fertilis.

Heterorthis clytie.

Dinorthis pectinella
Hebertella clytie?

Girvanella sp.

Solenopora sp.

Eospongia sp.

Agnostus sp.

Malcurea magna
Hormotoma artimesia

This list seems to indicate that the Chickamauga is early
Ordovician in age, as there are forms here which are charac-
teristic of the Beekmantown, Chazy and early Trenton of New
York. Almost the same fauna has been described by Ruedemann^
from a conglomerate inclosed in the Normanskill shales at Ryse-
dorph Hill, Rensselaer County, New York. The conglomerate is
made up of pebbles of Beekmantown, Chazy, and early Trenton
age. Beekmantown fossils, however, are also found in the upper
Shenandoah, but here are also found Cryptozoons characteristic
of the Ozarkian system.

Portions of the above listed fauna are also found in the Stones
River, Chambersburg, Murat, Athens, and Holston formations.
In the Chickamauga, there is also found resemblance, faunally,

* For the most part, after Bassler and others.

® Ruedemann, R., ‘Trenton Conglomerate of Rysedorph Hill and its
Fauna.” Bull. 49, New York State Museum, 1908, pp. 1-115.

Ophileta complanata
Stylarea parva
Echinosphaerites surantium
Isotelus gigas
Illaenus americana?
Rafinesquina sp.
Strophomena sp.

Leptaena rhomboidalis
Orthoceras sp.

Batostoma sp.
Plectambonites pisum

332

HUBBARD AND CRONEIS

to the Birdseye (Lowville) limestone of New York and its equiva-
lent, the Tyrone formation of Kentucky. The Hermitage and
Bigby formations of Tennessee are also closely related to the
upper Chickamauga of Giles County.

The Chickamauga Formation Subdivided

Section along the Narrows of the New River in the Virginian
Railroad cut.

1. A coarse chert breccia, with fragments of non-crystal-
line limestone in a crystalline matrix. The chert fragments are
two to fifteen inches in their longest dimension, are angular, and
lie in all positions in reference to the bedding plane, often being
in contact and sometimes in apparent layers. No calcite veins.

3 to 10 feet.

The chert in the breccia mentioned above is identical with the
fragments which weather out of the Shenandoah today.

2. Two layers of fine chert breccia, the fragments being two

inches or less in their greatest dimension. Fragments are rarely
in contact, nor are they in distinct beds, but are scattered
throughout the somewhat crystalline matrix. A normal fault
of 2 feet cuts across these two horizons. 6 feet.

3. A finer grained chert breccia, the fragments being from
one inch in their greatest dimension down to the most minute,
but it is clearly a breccia, for the fragments occur in great num-
bers and lie in all positions. Quantities of these are collected at
various intervals into beds, the fragments becoming smaller and
fewer upwards, but they end abruptly near the top. The matrix
is a fine grained, gray limestone in layers of four inches to four
feet. No calcite veins, looks like the Shenandoah. 45 feet.

4. A partly covered interval. Fine grained, light colored,

medium bedded limestone with some shale partings. The calcite-
veined chert extends to the base. The limestone beds are dove
colored to dark blue and often have dark chert nodules, which
sometimes are arranged in beds. There is some calcite veining
in the chert. Toward the top of the section dark blue chert pre-
dominates with light colors more characteristic of the lower
layers. There are open joints and bedding planes, and the usual
weathered or water-rounded forms so characteristic of this
formation. 243 feet.

GEOLOGY OF GILES COUNTY, VIRGINIA

333

Brachiopods were found about 50 feet above the breccia, hence
low in this member, on the west side of New River.

5. Dark blue to black, fine grained, dense, non-crystalline

limestone with the bedding concealed, and not developed by
weathering. There is considerable black chert in nodules and in
layers of nodules. These nodules, as well as the limestone itself,
are veined with calcite. The chert is brittle and ferruginous, and
both the chert and the limestone weather a rusty brown. Calcite
is light and conspicuous. Jointing is meager. Pyrite crystals
occur. 20 feet.

6. A very dark, blue black limestone with a hackly, rough

fracture. Many valcite veins and some bundles of calcite crystals.
The veins run in all directions, but the larger ones are at right
angles to the bedding plane. Bedding is irregular. Pyrite
crystals are common. 7 feet.

7. Fine, even grained, light gray to bluish limestone with close

bedding. Fracture is smooth, fluted, and curved. This division
looks and sounds flinty. Only a few calcite crystals and veins.
No chert. Two layers ; the upper being the lighter. Considerable
pyrite, crystalline lenses in the middle portion. Weathers a light
brown. 41/? feet.

8. Massive, light gray layer of fine grained, flinty limestone,
with many small calcite veins, as well as some pyrite in scattered
crystals and veins. Conchoidal fracture. Beds thicken and
thin out locally. Weathers a little rusty but lighter than the
rock. Boundary between 8 and 9 rather indefinite. 5 feet.

9. Massive, coarsely crystalline, dark blue limestone with

cuboidal fracture. Bunches and veins of calcite occur, mostly in
the joints. This division has the ap.pearance of granite at a short
distance. No chert or fossils. At one time this bed was used
extensively for lime. Weathers a rusty grey. 16 feet.

10. Dark blue to black, thin bedded limestone, with many

chert layers in black brittle nodules. Fine grained, calcite veined,
fossiliferous matrix with the chert nodules, which weather out.
Pyrite crystals, also brachiopods, cephalopods, crinoid stems, and
corals. ' 15 feet.

11. Partly covered interval. A dense crystalline, dark lime-
stone. Some chert and many calcite veins. Weathers almost
white. Fossils as in 10, with the addition of gastropods.

83 feet.

334

HUBBARD AND CRONEIS

12. Heavy bedded, blue limestone, one to seven feet in the
thickness of the layers, cherty and calcite veined as well as con-
taining large crystals of calcite. Master joints. Weathers rusty
and deep, showing the weathering to a depth of forty feet. Fos-
siliferous. Bryozoans are the most abundant, but horn corals,
crinoids, cephalopods, and brachiopods in several species occur.

89 feet.

13. Coarsely crystalline, mostly thin bedded, steel gray to

blue limestone, with several thin shale partings. Very fossi-
liferous — especially towards the bottom, much as in No. 12.
Thicker bedded toward the top, with calcite veins becoming
abundant; no chert. 16 feet.

14. Shaly, steel gray limestone and calcareous shales, thin
bedded. Very fossiliferous but fossils very much broken up.

2 feet.

15. One solid layer of dark blue, crystalline limestone,

strongly calcite veined and carrying many broken and mashed
fossils. 2 feet.

16. Thin bedded limestone, more or less argillaceous, with

shale layers. The limestone is crystalline and very fossiliferous,
especially near the base. Beds are for the most part under four
inches in thickness. There is very little chert or calcite, and only
a few joints. 20 feet.

17. Heavy bedded, dark steel gray limestone. Coarse and

fine grained in different layers. Very much mottled with small
clay lenses and streaks. Calcite veins occur complexly branching
as well as chert nodules which are often cut by these veins.
There are two joint systems at right angles to the bedding plane.
Weathers with less rounding than the ordinary Chickamauga.
Tetradium remains rather abundant. Beds 3-8 feet thick. Would
quarry well. 50 feet.

18. Thin bedded, fine grained, cherty limestone, gray to black

in color. There are many thin clay partings and beds or layers
of chert nodules are characteristic. There are a few calcite veins.
Weathers light. Fossils are rare. 20 feet.

19. A partly covered interval. Light to, dark grayish blue
limestone which is medium to thin bedded. Calcite veins and
black chert nodules in layers. Bryozoans found. 105 feet.

20. Argillaceous limestone, showing thin beds grouped into
layers of two to eight inches. The layers are alternately clay and

GEOLOGY OF GILES COUNTY, VIRGINIA 335

limestone. The color is grey blue. There are many white calcite
veins and some pyrite crystals. No fossils or chert. Weathers
light. 15 feet.

21. Thin bedded gray limestone, with thin shales, rarely

veined with the exception of the bottom layer. Much mottled
with small amorphous masses in a coarser crystalline matrix.
Seems to be slightly conglomeratic. There are many fossil
fragments ; bryozoans, trilobites, crinoid fragrnents, brachiopods,
corals, etc. 7 feet.

22. Coarse crystalline, light gray limestone, strongly veined
with white calcite and some pyrite. There is no chert, but there
are many fragments of fossils and some very whole and distinct,
girvanella, brachiopods, bryozoans, trilobites and pelecypods.
There is one mottled conglomeratic layer as in 21. The joints
are irregular and are, for the most part, filled with calcite. The
weathering emphasizes the amorphous inclusions. 41/2 feet.

23. Dark blue to gray, fine grained, non-crystalline limestone,

shot with numerous calcite veins. Bedding emphasized by
weathering. Dip joints. Has clay conglomerate or breccia.
Ends with layers about three feet above the first rocks which
have the Moccasin appearance. 22 feet.

The samples collected from the various horizons of the Chicka-
mauga limestone in this section show a remarkable uniformity in
composition. The high lime content of these strata is indicative
of their present exploitation in other parts of the state and of
their future development here.

Analysis of Chickamauga Limestone,
Narrows section, Virginia^®

(J. H. Gibboney, Analyst)

1

2

3

Insoluble

5.60

1.50

2.30

Alumina

Iron oxide

j- 0.78

0.56

0.60

Lime

51.40

54.76

54.06

Calcium carbonate

91.80

97.78

96.54

Magnesia

...... 0.72

0.15

0.30

Magnesium carbonate ....

1.52

0.31

0.64

10

Bassler, R. S., ‘‘Cement Resources of Virginia.” pp. 189,

336

HUBBARD AND CRONEIS

The Moccasin Limestone

The Moccasin Limestone, correlated with the Athens Shale
and the Tellico Sandstone of Eastern Tennessee, marks, the
transition from the hard blue limestone of the Chickamauga to
the Sevier calcareous shales. The formation is composed of red
and greenish blue earthy limestones having a mottled appear-
ance, and always weathering with a characteristic hackly appear-
ance. These limestones usually outcrop on the steep slopes of
the valley ridges and thus give a pronounced color to the land-
scape. The formation occupies a position stratigraphically in-
termediate between the great limestones beneath and the shales
and sandstones above. The exposed surfaces are often ripple
marked or mud cracked, indicating that the seas were much shal-
lower than before and at their minimum depth for a limestone
to be formed.

These limestones take their name from Moccasin Creek, Scott
County, Virginia. In thickness, they vary from 300 to 500 feet,
being 344 feet thick at the Narrows. There are several layers
which are of proper texture and composition to have value a«
lithographic limestones but are too thin and fragmented. They
have been tried as such by the U. S. G. S. Towards the top of
the formation, there are alternate limestone and shale beds in
which the limestone is gray blue, resistant with a hackly fracture
and splintering into fragments because the jointing is not at
right angles to the bedding plane. The shale horizons are very
weak, the red and yellow beds weathering rapidly into very sticky
clays. The entire formation exhibits the splintery fracture de-
scribed above. Calcite veining oecurs, but is not a dominant
feature.

Paleontology and Correlation

For some time, the Moccasin limestone has been regarded as a
transition formation between the great development of Ordovi-
cian limestones in the Powell valley and the equally great de-
velopment of shale and sandstone in the eastern portion of the
Appalachian Valley. If this were the case, and continuous ex-
posures could be had, the formation should grade into lime on
the west and shale in the east. Recent investigations show that
this is not the case and that the Moccasin is but a single Ordovi-

GEOLOGY OF GILES COUNTY, VIRGINIA

337

cian formationA^ Certainly, there is no appreciable gradation in
Giles County.

Fossils are rare, but specimens of Dalmanella testuclinaria and
Plectambonites sericeus were found as well as fragments of
Triarthrus becki. What faunal evidence there is, as well as the
stratigraphic position of this formation, indicates a Mid-Ordovi-
cian age. equivalent in part, at least, to the lower Utica division
of the New York classification.

The Moccasin Limestone Subdivided

Section taken at the Narrows of the New River, Giles County,
Virginia. First two members are on Virginian Railroad.

1. Bluish limestone, thin bedded and not obliquely jointed as

in the rest of the formation. The last two feet of this division
are separated from the rest by three or four layers which re-
semble the Chickamauga. Even bedded and calcite veined. Mud
breccia in this member. 10 feet.

2. Red to light brown, fine grained, even bedded limestone.

Jointing is oblique with splintery fragments which are empha-
sized by weathering. A few layers are bluish gray instead of
reddish. Beds are from one to fifteen inches in thickness. One
layer of hard, drab to grey lithographic limestone four inches
thick about twelve feet from the bottom. Mud cracks are un-
usually prominent. 90 feet.

3. Lithographic horizon. Starts up the ravine leading from
railroad to wagon road.

a. Hard, dense, blue, limestone layer with small calcite veins.

6 inches.

b. Continuation of normal Moccasin. 10 feet.

c. Second fine grained, hard, lithographic layer, cherty ap-
pearance. 1 inch.

d. Continuation of normal Moccasin. 1 ft. 8 inches.

e. Third lithographic layer. 2 inches.

The non-lithographic layers seem to be partly lithographic, but

of an inferior quality. Total, 12 feet, 5 inches.

4. Gray, greenish to drab, hard limestone in beds three to

twelve inches in thickness, weathering lighter and having the
same oblique jointing and splintery fragments as noted else-
where. 16 feet.

” Bassler, R. S., ‘Cement Resources of Virginia.” pp. 167.

338

HUBBARD AND CRONEIS

5. A covered interval on wagon road with soft shaly lime-
stone and calcareous shale in the float. 117 feet.

6. Limestone and shales alternating. Six limestone horizons
of gray to blue resistant beds. No chert nor calcite and rarely
fossiliferous. Argillaceous and breaking into splintery pieces be-
cause the jointing is both at right angles and oblique to the
bedding. Six shale layers of soft, crumbly, yellow and red ma-
terial, weathering into a reddish yellow, sticky mud, which
covers up the slopes.

Shales

17 feet (bottom)

Limestone

10

a

Shales

.....: ....18

a

Limestones

1

<<

Shales

3

<(

Limestones

3

a

Shales

10

a

Limestones

4

a

Shales

6

((

Limestones

5

Shales

3

<<

Limestones

8

“ (Top)

Total

88

<<

Analysis of Moccasin Limestone from
the Pearisburg section^-

(J. H. Gibboney, Analyst)

1

2

Insoluble

... 11.73

7.66

Alumina

■■■ 1.48

0.82

Iron oxide

.... 47.78

Lime

50.38

Calcium carbonate

... 85.32

89.96

Magnesia

0.24

0.35

Magnesium carbonate

... 0.58

0.76

Total

... 99.11

99.20

1. Impure, drab

limestone.

2. Red, clayey limestone.

Bassler, R. S., “Cement Resources of Virginia.” p. 194.

GEOLOGY OF GILES COUNTY, VIRGINIA 339

The Sevier Shales

This formation, showing the transition from limestones to
sandstones above, forms the steep slopes of the larger valley
ridges. It takes its name from Sevier County, Tennessee and
corresponds with the late middle and upper Ordovician of New
York, that is, the late Utica and Eden shales. It is also probably
equivalent to the Maquoketa shales in Iowa as well as part of
the lead and zinc bearing formations known as the Galena lime-
stones.

This formation, which varies from calcareous shales at the
base to sandy shales at the top, is from 1250 to 1500 feet in thick-
ness, the section at the Narrows measuring 1341 feet.

These shales are fossiliferous throughout, corals, graptolites,
sponges, bryozoans, and cephalopods being found rather com-
monly. In the upper layers trilobite fragments are found and
pelecypods are common. Brachiopods are found throughout.
Plectamhonites sericeus is especially numerous and seems to be
characteristic of certain beds in the formation.

The shales are interbedded with thin limestone layers in many
places, and on the whole the formation is weak and non-resistant
as well as being thin bedded throughout. Like the Russell forma-
tion, these shales are also folded and contorted. The bedding is
clearly defined but the jointing is not conspicuous except where
it forms cuneiform pits. Blue, brown, green and gray color com-
binations are the most common ones, with calcite veining rather
marked in some places.

This formation passes up into the overlying sandstones rather
abruptly and thus the dividing line is not so difficult to establish
at the top as at the bottom, where Moccasin conditions seem to
reappear several times after many feet of Sevier shales.

Paleontology and Correlation

In Sevier County, Tennessee, the formation overlying the
Tellico, has been named the Sevier. This formation is not very
fossiliferous ordinarily, but has a fairly well developed fauna
in Giles County. Fragments of Triarthrus becki, Plectamhonites
sericeus, Rafinesquina alternata, R. squamulata, Calymene sp.
and Zygospira sp. are most commonly found but both Diclymo-
graptus and Monogmptus types of graptolites are also present.

From the faunal evidence, the shales are late middle or upper

340

HUBBARD AND CRONEIS

Ordovician, The fauna, (what little can be found) of the Moc-
casin is also present in the Sevier so that there is no great differ-
ence in the age of these two formations. Late Utica, Eden and
possibly early Lorraine, seem to be the times in the New York
Ordovician scale, which are comprised in the Sevier of Giles
County.

The Sevier Subdivided at the Narrows Section.

Wagon road above Virginian Railroad

1. A hard, blue, even-bedded non-fossiliferous limestone, ex-
hibiting the characteristic Sevier cleavage. One layer.

11/2 feet.

2. Gray, crumbly shale, weathering to clay. 2 feet.

3. Even-bedded limestones and shales. The former in four
to eight inch layers, blue to dark blue, hard, and all but non-
fossiliferous. The shales are in two layers, one being green and
the other yellow, besides many shale partings. The jointing gives
cuneiform pits in the limestone. Fossils begin in this horizon.

18 feet.

4. Calcareous shales and thin limestones like the upper part

of this formation, but more of a greenish gray color, and more
crumbly. Soft with few fossils. This is the end of the transition
from the Moccasin. A partly covered area. 20 feet.

5. Blue limestone in beds of one to eight inches. Fossils un-
common. A little shale and some calcite veins. 8 feet.

6. Shale with a slaty cleavage, dark blue, green and black

in color. Fissile, much jointed and thin bedded. The shale is
rather calcareous. Fossils are rare. 19 feet.

7. Thin limestones with a few interbedded thin shales. The
limestones one inch to one foot in thickness, being dark gray to
blue but weathering lighter and leaving much residual clay.
Calcite veins are numerous and branching and some are as much
as an inch and a half in thickness. This division is fossiliferous
with the shells being much broken. The veins and fossils both
weather out. Much jointed and cracked. Shale partings occur
and are from paper thickness up to six inches, but they are not
arenaceous. The beds are bent, crumpled, and folded as well as
being faulted locally. Very fossiliferous. The brachiopods Dal-
manella testudinaria and possibly suhaequata and Plectamhonites
sericeus being very common and characteristic. 386 feet.

GEOLOGY OF GILES COUNTY, VIRGINIA

341

8. Thin limestones, one to twelve inches in thickness, inter-

bedded with thin blue shales. More than half is limestone, hard,
dense, blue, fossiliferous and calcite veined. Talus consists of
limestone almost entirely. The limestone layers thicken and thin
and are sometimes bent so as to reverse the dip. Several small
concretionary layers are present. The upper feet are more limey
and thicker bedded. In the central portion Monticulipora sp. are
common and toward the top there are several species of coral.
In the lower portion many graptolites of the Diclymograptus and
Monograptus types, Asaphus gigas, Rafinesquina alternistriata,
Chaetetes sp., Lophospira sp., Bellerophon sp., and Oj^thoceras sp.
are found. 224 feet.

9. A series with more shale than limestone, in little beds, none
of which are more than one inch in thickness. Only about forty
feet of this horizon is exposed. Fossils found are Calymene sp.,
Raphistoma peracutum and a Monticulipora species.

175 feet.

10. Alternating shales and thin limestones much like layer
number 12. There are no distinct layers and the divisions are
marked by numerous small faults of less than 15 inches.

123 feet.

11. Contorted limestone beds with interbedded calcareous

shales, and limestones. There are six layers, two near the bot-
tom are two feet thick, then there are three layers, two to three
feet thick, and a single three foot layer at the top. The fourth
layer from the bottom has a conglomeratic phase near its top
which was seen in both the railroad and wagon road cuts. Fossi-
liferous. Calcite veined. The limestone is blue while the shales
are brown and greenish grey. 85 feet.

12. Calcareous shales, thin bedded, blue, greenish and brown,
with many thin blue limestone layers full of fossils. The lime-
stone weathers rapidly by solution leaving clay where the lime-
stone layers were. Thus the limestones are usually indented in
a weathered cut. Calcite veins are very abundant. 80 feet.

13. A limestone layer, grey to olive green and jointed so as

to give “V” shaped notches and the cuneiform pits, 1-6 inches
wide and 1-20 inches long. Surface weathers smooth but sharp
angled corners project. 2 feet.

14. Calcareous shales containing a few layers of hard blue
limestone. The limestone is very fossiliferous and in beds

342

HUBBARD AND CRONEIS

6-12 inches thick, and contains calcite veins. The shales are gray,
green and indifferent tints, and also fossiliferous. There are
many thin sandstones 1-3 ft. thick jointing into regular angular
and cubical blocks. The shales weather rusty and the limestone
weathers by solution leaving fossil cavities and red clay.

113 feet.

15. Thin bedded, greenish, gray blue, calcareous shales with

thinner, stronger layers mainly of flinty sandstone but none of
limestone. There are many fossiliferous horizons some of which
weather out porous. Brachiopods, pelecypods and bryozoans
occur. 44 feet.

16. Thin bedded, bluish green, calcareous, and sandy shales

with thin 2-4 in. sandstone layers every foot or two. These
latter weather out in angular pieces like chert layers. There are
many fossil zones and scattered fossils throughout the whole
horizon. 18 feet.

17. Thick bedded, massive, dark olive green, calcareous sand-

stone in some places weathering shaly and in others like sand-
stone. There are many horizons of broken and well-preserved
fossils. Brachiopods occur 6 ft. from the top. The rock is richer
in fossils than the Bays. 19 feet.

The following analyses of the Sevier Shales will serve to indi-
cate their approximate composition at the Narrows although the
samples listed below were taken near Goodwins Ferry which is
more than 20 miles up the New River.

Analyses of the Sevier Shale^^

(J. H. Gibboney, Analyst)

1

2

3

Insoluble

5.12

41.48

71.88

Alumina

Iron oxide

2.92

6.04

8.56

Lime

51.16

28.00

8.54

Calcium carbonate

91.39

40.00

15.25

Magnesia

0.25

0.30

1.27

Magnesium carbonate

0.53

0.64

2.68

1. Thin bedded, blue limestone, lower part of the Sevier.

2. Calcareous shale from the lower horizons of the formation.

3. Sandy shale from the Eden horizon of the Sevier Shale.

Bassler, R. S., ‘‘Cement Resources of Virginia,” p. 200.

GEOLOGY OF GILES COUNTY, VIRGINIA

343

The Bays Sandstone

The sandstones and shales overlying: the preceding: formation
are for the most part, red, yellowish red, or purplish red, but
there are some g*reen blotches which resemble, but are not, sur-
face features. The thin bedded sandstones at the top pass
downward into sandy shales, keeping the prevalent color and
merging at last into the Sevier below. The formation takes its
name from Bays Mountain in Tennessee.

This sandstone scratches very easily and weathers shelly.
Some layers show cuneiform jointing developed to an unusual
degree, and the jointing is good throughout, there being master
joints in several localities. In some places, the sandstone is
slightly quartzitic but for the most part the formation has been
but very little metamorphosed. The fracture is usually uneven
to conchoidal.

The conditions were not especially good for life development
during the time these rocks were laid down, nor is the formation
a good one for preserving fossil forms had life been present,
hence fossils are found mostly in the lower, niore shaly layers.
There are several very distinctive nodular layers and cross bed-
ding is quite noticeable as well as ripple marks, all indicating
shallow seas. In the top layers, there are fine flakes of primary
mica as well as some secondary chlorite along joint and bedding
planes. The total thickness of the formation at the Narrows is
321 feet.

Usually the crest of the ridges is formed of Clinch, with the
red Bays outcropping below, but in some places, especially in low
gaps, the Clinch has been eroded away and the summit is then
formed of the Bays Sandstone.

Paleontology and Correlation

Fossils in some of the lower layers are well preserved and fairly
numerous. HeberteUa sinuata and Orthorhynchula linneyi are
found throughout, as well as a large, unidentified ramose
bryozoan.

It would seem from the faunal evidence as though the Bays
was either Lorraine or Richmond in age. Lorraine forms seem
to predominate. If this correlation is correct, the Bays sandstone
of Giles County is younger than the typical Bays of Tennessee,

344

HUBBARD AND CRONEIS

which is beyond question Middle Ordovician (Black River)

In this case, the name Bays is a misnomer, as applied to these
red sandstones of Giles County. In northwestern Virginia, the
name Juniata has been applied to a similarly situated red sand-
stone, whose age is beyond doubt lower Richmond. It would
seem, then, that the name Juniata might be used here rather
than Bays.

The Bays Sandstone Subdivided
N^arrows Section. (Wagon road)

1. Medium bedded sandstone with thinner shales, green

blotches becoming bands in places. Even bedded, several layers
carrying broken fossils, red with iron. Base of formation marks
the change in color from dark red to green. 20 feet.

2. Thin bedded, purplish shaly sandstone, carrying several

beds of broken shells. Trilobite fragments are common. A fer-
ruginous layer. 9% feet.

3. Lower nodular layer flattened, concretionary-like masses

one to two inches thick and six to ten inches broad. These are
not concretions, and do not take the iron rust on the curved clea-
vage faces as do those of similar appearance in the upper nodular
layer. The upper and lower parts are the richest in these
masses and are the most shaly. The middle is more massive and
sandy with conchoidal fracture and many green blotches. Fos-
sils are in fragments in the upper portion. 5V2 feet.

4. Cross bedded layers of dark red sandstone with thin in-

terbedded shaly sandstone layers. All are cross bedded even to
great wedge-shaped masses of many layers. Some ripple marks^
and much chlorite in the joint planes as well as some on the
bedding planes. Quartz is also found deposited in veins. Slick-
ensides along some bedding planes. 32 feet.

5. Thin sandstone layers which are arenaceous, micaceous,
and shaly. This division is dark red, thin bedded and crackled,
and much shot with minute joints. When, it is freshly exposed, it
resembles a single massive layer, but with weathering it crumbles
into fragments. Top layer is a thin green shale. 2 feet.

6. Upper nodular layer. Dark red sandstone, upper one and
one-half feet massive, even grained and breaking with curved
surfaces which scratch very easily. Middle two feet are nodular

Stose, G. W. and Miser, H. D., “Manganese deposits of Western Vir-
ginia,” pp. 29.

GEOLOGY OF GILES COUNTY, VIRGINIA

345

and look concretionary but are not. Curved pieces break out
giving rounded masses, but each has the same composition as the
rock above and below. Red, ferruginous quartzitic sandstone
with quartz veins. Weathering of the iron has gone on along
these curved planes and thus has aided the spheroidal breaking.
The lower two feet are rarely nodular but otherwise they have
the same appearance. 51/2 feet.

7. Red sandstone and arenaceous shales, which when first

exposed, seem to be thick, massive beds. When weathered, the
thin shaly beds appear and the rock crumbles. Fine and even
grained with little cross-bedding. Regular for long distances.
Usually dark, brick red, rarely gray. Scattered green blotches
occur as well as calcite veins. Fine flakes of mica are probably
primary but the chlorite veins are secondary. 47 feet.

8. A covered interval, which from the float seems to be largely
soft gray and green as well as red sandstones and shales.

197 feet.

Analyses of a Single Sample of the Bays Formation
from near Glade Springs, Virginia.^^

(J. H. Gibboney, Analyst)

Per cent

Insoluble 90.18

Alumina and Iron oxide 5.72

Lime 0.64

Calcium carbonate 1.14

Magnesium 0.03

Magnesium carbonate 0.07

THE SILURIAN SYSTEM

Introduction

The Silurian rocks of Giles County are dominantly sandstones,
(sometimes semiquartzitic) , but there are also interbedded
shales, and a few conglomeratic layers. These rocks are divided
into the Clinch and Rockwood formations, but in addition some
rocks classed as the lower Giles may be in part Silurian.

Silurian strata outcrop in a continuous band, about a mile and
a half wide, along the northern border of the county, but do not
extend into the panhandle because they dip south and thus in

Bassler, R. S., “Cement Resources of Virginia,” p. 170.

346

HUBBARD AND CRONEIS

the v*alley they are carried south. They are also present over a
considerable area in the eastern as well as the western mountain
areas, but their outcrop on the Walker Mountain range lies only
in a narrow strip which is very restricted in Giles County.

The Clinch and the Rockwood are both mountain making rocks
and they are usually found capping ridges. Iron ore of the Clin-
ton type is found in the Rockwood but has not been exploited to
any extent here. There are about 550 feet of Silurian strata in
Giles County.

The Clinch Sandstone

The Clinch Formation, taking its name from Clinch Moun-
tain, is found throughout the entire Appalachian system. It
corresponds to the Medina Sandstone of New York. All the
important valley ridges owe their existence to this heavy plate
of sandstone which has preserved summits at or nearly at the
level of the oldest recorded peneplain, while adjacent areas have
been eroded to the present valleys.

This formation is easily separable from all the others because
of its massive character. It usually varies between 125 and 300
feet in thickness, there being 140 feet in the Narrows exposure.

This rock is a semi-quartzitic sandstone, coarse to fine grained,
sometimes conglomeratic with large quartz pebbles. Slicken-
sides are rather common because the beds are so stiff that they
break and slide over each other rather than bend. The formation
weathers light brown to yellowish bronze color, red and purplish
red occurring in places. It has an uneven fracture, is fairly even
bedded, and very dense and resistant. These rocks form the
larger rapids at the Narrows of the New River.

The formation contains arenaceous shale layers which be-
come more numerous towards the top. While fucoids are found
in some places, the formation may be regarded as practically non-
fossiliferous.

Paleontology and Correlation

The Clinch thickens off to the north and east, so that while
in Giles County its thickness is 140 feet, it is 300 feet thick in
northern Virginia where it makes Cacapon Mountain. On Mass-
anutten Mountain, sandstones of equivalent age are called Mass-
anutten, while in Pennsylvania and Maryland, the same forma-
tion is known as the Tuscarora sandstone.

GEOLOGY OF GILES COUNTY, VIRGINIA

347

Fossils are rare, but some specimens of Lingula cuneata can
be found in the shaly division. Excellent specimens of Scolithus
verticalis and Arthrophycus harlani have been found on Angels
Rest and Peters slopes. What faunal evidence can be found then,
as well as stratigraphic position and lithologic character, seem
to indicate Medina age for the Clinch.

The Clinch probably rests unconforniably upon the upper
Ordovician Bays sandstone.

The Clinch Sandstone Formation Subdivided
Narrows Section

1. Lower part of Clinch, Sandstone in layers from one inch

to eight feet, with thin arenaceous shale partings, one-fourth to
three inches in thickness. Colors are gray and greenish blue as
well as a purplish gray and it is not until weathered that the
formation assumes the bronze red tint due to the iron impurities.
Quartz pebbles cemented with iron, silica and colored by the iron
are metamorphosed into a fair quartzite. The pebbles attain a
size commonly equal to that of a hickory nut, rarely 2-3 inches
in diameter, and are of older quartzite and vein quartz. There
are some minor faults in this division, 120 feet.

2. Upper layers. Five shale layers, nearly four feet thick, all
arenaceous, in variegated colors of green, blue, red and brown as
well as various tints, and being thinly laminated — separated by
four layers of quartzitic gray sandstone of about six inches in
thickness. These beds vary notably from place to place.

20 feet.

The Rockwood Formation

This formation takes its name from Rockwood, Tennessee,
where it has been used as an iron ore for many years. It is a
heterogeneous mass of shales and sandstones, corresponding to
the Clinton formation with its iron ore of New York and Ala-
bama. In the Narrows of the New River, 292 feet of this forma-
tion are exposed but in some localities its thickness runs as high
as 400 feet.

In some places, the sandstone is semiquartzitic, and such a
layer forms the upper rapids in the New River at the Narrows.
The jointing is good and is for the most part cuboidal. The dom-
inant color of the formation is red on account of the large iron
content. These rocks are fossiliferous to some extent, fucoids.

348

HUBBARD AND CRONEIS

bryozoans, brachiopods, pelecypods, trilobites and corals being
recognizable but in many places the fossil remains are too frag-
mentary to be identified.

The Rockwood is extremely thin bedded in some localities but
the average bedding is medium. Ocherous sands occur in places
and several layers could be used for building purposes with ex-
cellent results. One quartzitic layer with a conglomeratic phase
is very similar in every respect to the Clinch.

Many of the higher ridges are capped with Rockwood which
is sometimes the source of the mountain iron ore. The ore, how-
ever, is in this locality either of such low iron content or is so
inaccessible that it promises no definite economic value for years
to come. In the case of the Rockwood ore, it seems as if the
upper layers in being eroded away have left their iron content
to be leached down into the lower layers and thus they are
always the richest ones.

Paleontology and Correlation

Fossils are usually quite numerous in the Rockwood, but in
Giles County only a few were identified. The age of these fossils
is Clinton. In some places in the state, rocks of Cayuga age
have also been called Rockwood, but in Giles County, this forma-
tion is entirely Clinton.

The white quartzitic layer near the top is thought by Stose
and Miser^® to be of the same age as the Keifer sandstone of
Pennsylvania and Maryland.

The Rockwood Formation Subdivided
Narrows Section — Wagon Road

1. Thin shales and argillaceous thin sandstones, in a variety
of colors, such as blue, red, and green. Weathers to sandy mud.
Much jointed and crumbly. Several red sandstone layers in the
shales. At the base are found Camarotoechia neglecta in two
zones about eight feet apart, very abundant but quite alone.
About 75 feet above these fossil beds a rich fossil horizon occurs
carrying Anoplotheca plicatula, A. hemispheriaw, A. plano-con-
vexa, Chonetes cornutus, B^ocalymene clintoni, Buthotrephis
gracilis, var. crassa and var. intermedia. About 114 feet above
the base are found Bumastus barriensis, Qalymene hlumen-

Stose, G. W. and Miser, H. D. “Manganese Deposits of Western Vir-
ginia.” pp. 30.

GEOLOGY OF GILES COUNTY, VIRGINIA

349

bachii, Liocalymene clintoni, Beyrichia lata. This array of forms
establishes the Clinton age for the Rockwood, and suggests that
the lower Rockwood is the equivalent of the middle or upper

Clinton of New York. 120 feet.

2. Dense, quartzitic sandstone in three or four layers, one of

which is about 18 inches thick. The sandstone is coarse grained
at the base. 3 feet.

3. Ferruginous shales and sandstones in alternate beds. The

average color of the sandstones is red. The shales are thin, gray
and green. 18 feet.

4. Dark red, ferruginous, quartzitic sandstone, irregularly

bedded and jointed. Weathers to a rusty brownish red. Irregu-
lar blocks as large as five feet thick weather out. Hematite in
certain places. 5 feet.

5. Alternating sandstones and shales. The sandstones are

two to five inches thick and are red and grey, dense and quart-
zitic. Regular cuboidal jointing into brick like blocks. Thin
shale beds of a smooth greenish gray color and not sandy.
Bryozoans are common. Fucoids? 6 feet.

Section described now goes to Virginian cut.

6. Shales, having soapy feel, without grit. Gray, green and

yellow, weathering soft, punky almost black. Thinly laminated.
Brachiopods. 13 feet,

7. Layers of blue, gray, and pink, dense quartzitic sandstone,

with a little shelly material in the upper half. Weathers a dark
brown and red. Atrypa reticulaias. 6 feet.

8. Coarse buff sandstone, not cemented and not quartzitic

with ferruginous veins with crooked branching, which seem to
be impregnation of the natural pore spaces between the grains
of sand. Iron is more abundant and much darker red than usual
in this division. There are many cavities an inch or less across.
The rock is thin bedded but one layer in the middle part is 2 —
21/2 feet thick. Possible bryozoans were found. 7 feet.

9. Gray sandstone, with fine gray blue shale layers. The

sandstone is quartzitic in beds of two to eight inches. One group
seems to be a heavy one but shows thin when weathered. Near
the bottom several layers are a pronounced red and weather
rusty. Strong cross bedding. No fossils. 15 feet.

10. Black, carbonaceous, shaly layers, as well as red, brown
and gray ferruginous layers. It is always sandy with quartz

350

HUBBARD AND CRONEIS

grains rounded and some of the cavities are quartz filled. A
few red sandstone layers. The shale is fissile, thin bedded and
weak. Fossils found but badly mashed. 7 feet.

11. Strong sandstone layers, one to six inches thick, gray,

reddish and mottled. Weathers a dark red and rusty. Layers
are even and continuous. Very thin, sandy shale partings.
Pelecypods. 2 feet.

12. Soft, shaly sandstone in thin beds, weathering easily
into clayey sands. Dark gray, yellowish and brown. Brachiopods.

2 feet.

13. Ripple maker. Resistant gray quartzitic sandstone with
pink lines and gray mottling, heavy and cross bedded. Heavy
pebbles in a fine grained matrix and resembles conglomeratic
layers of the Clinch. Cavities of considerable size are more or
less filled with chalcedony and quartz crystals. No fossils seen.

91/2 feet.

14. Covered interval of soft shaly material. 38 feet.

Near the base were found Tentaculites minutus, and Tellun-

omya lata.

15. Layers of purple and red, quartzitic sandstone. Fine

bedding lines of alternate light and dark red often are apparent.
Two to six inch layers grading off thinner and weaker toward the
top. Weathers a rusty bronze. . 71/2 feet.

16. Three to six layers of dense, hard red to purple quartzitic

sandstone, even bedded and fine grained. Some of the layers
split up on weathering into two or three layers. Would make a
handsome building stone as it weathers a beautiful bronze.
There is one greenish layer. 31/2 feet.

17. Between fifty and seventy layers of slightly argillaceous

sandstone and quartzitic sandstone, becoming thinner and
weaker towards the bottom. 2 feet.

18. Strong quartzitic sandstone beds two to eighteen inches

in thickness and slightly crackled and broken. Gray, greenish
and red in streaks. Weathers rusty, reddish and rough. Five
feet from the top is a layer of loose material, caused by the
weathering and leaching of a more porous layer. Ocherous sands
in some places ; in others apparently concretionary. It probably
is not concretionary but is a residual structure brought out by
weathering. Corals near the bottom. 15 feet.

GEOLOGY OF GILES COUNTY, VIRGINIA

351

19. Thin bedded sandstones with little shale partings; sand-
stones one-fourth to five inches thick. Buff to gray with no red.
Weathers a uniform buff. Shattered and crackled but there are
no master joints. Some layers are quartzitic but some are also
loose sands. Some layers have the appearance of one in un-
weathered surfaces. Myriads of Cytherellina in the middle.

13 feet.

This does not complete the section, as a part of the Rockwood
is faulted out. On the west side of the river the fault continues
westward but is some distance farther south so as to leave all the
Rockwood and a considerable section of Giles north of the fault.
There may well be, then, 100 feet or more of Rockwood missing.

THE DEVONIAN SYSTEM

Introduction

The outcrops of Devonian strata are confined to restricted
exposures having a general northeast southwest strike. One of
these outcrops is on the northern flank of Brushy Mountain,
another extends into Giles County from Bland on the west, and
appears for some little distance to the east of the Stange mine
on Flat Top Mountain. Still other outcrops are found in the
upper courses of Clendenning, Little Stony, Stony, and Johns
Creeks, as well as in a small strip across the Panhandle. In the
south slopes of East River Mountain are considerable areas of
Giles beds extending from New River almost to the Bland-Giles
county line.

There are no good sections of lower Devonian exposed in
Giles County so that there is some confusion as to the exact age
of the Giles formation. Some of the rocks which appear above
the Clinton, and are almost certainly Cayugan in age, are classed
as Giles, yet the upper Giles bears a marked resemblance faun-
ally, stratigraphically, and lithologically to the Oriskany. There
are also occasionally limestones and cherts below this sandstone
which have been referred to as Helderbergian.

The Oriskany formation is of importance since it is in this
horizon that many of the manganese prospects of the county are
located. The other divisions have no economic value. The en-
tire Devonian as observed in this area is less than 3000 feet in
thickness, but it occurs in such scattered outcrops, and in places
is so faulted that this figure may be either too large or too small.

352

HUBBARD AND CRONEIS

Limestones to limey shales, to black shales, grading at last to
sandstones at the top, constitute the normal succession of Devon-
ian strata in Giles County.

The Giles Formation

Above the Rockwood is a group of strata of diverse charac-
teristics, but hard to separate in the field. In the Kimberling
Creek area, in the western portion of the county, there is at the
base of the Giles some forty feet of blue limestone, calcareous
shale at the base but heavy limestone at the top. This is followed
by coarse, ferruginous sandstone, some fifteen feet in thickness,
made up of small quartz pebbles. Above this, there is cherty
limestone, about thirty-five feet thick, which is always present
along the outcrop and is the key to the subjacent strata, and fol-
lowing this, there is an undetermined thickness (probably less
than 100 feet) of yellow-green sandstones.^^

Paleontology and Correlation

Little time was spent on the fauna of the Devonian formation.
The upper divisions of the Giles are Oriskany and Helderbergian
in age, but the two lower divisions, as described above are with-
out faunal record in Giles County. On the south slope of East
River Mountain, between Narrows and the west county line,
there are many exposures of the beds grouped as Giles. They
are cut somewhat parallel to Wolf Creek by a fault so that their
resistant layers repeat in places to form several rocky ridges.
Farther west in Wolf Creek Valley and quite near the county
line the Giles outcrops in two strips with Rockwood above the
northern strip and again between the strips, while Shenandoah
appears to the south. A fault has let the Giles down against the
Rockwood, thus preserving it. Erosion has removed the Giles
from a part of the Rockwood farther down the slope and a large
fault near Wolf Creek has carried the Shenandoah up to the
height of the Giles. In these areas considerable detailed work
has been possible, and the following correlations have provision-
ally been made :

1. Blue calcareous beds varying from firm limestones toward
the top to weak shales at the base, and resting immediately on
the Rockwood. 40 feet ±

Campbell, M. R., U. S. G. S. Folio No. 26.

GEOLOGY OF GILES COUNTY, VIRGINIA

353

2. Rather even bedded sandstone and coarse but even grained

sands well cemented with iron oxide. Many molds of pelecypods
in the main poorly preserved. 20 feet ±;

3. Limestone and chert. Whole beds are of chert, others are
a chert breccia with a meagre limestone matrix. In no place was
number 4 present with number 3 eroded away. Fossils were
found in the chert only. The colors are red, tan, pink, yellow
and gray. The bedding is irregular to imperfect.

40 feet ±:

4. Coarse yellow, buff, tan and green sandstones in part

loosely cemented, in part almost quartzite (boulders travel long
distances in the float). Many molds of Spirifer mucronatus,
with hinge line much extended and a few S. arenosus. Some of
the beds are shaley but the member is for the most part sand-
stone. 100 feet ±

These four members were found together in two or three
places and one or more of them were recognized repeatedly but
they never could be traced far. They became covered with their
own waste or float from the Rockwood. Nevertheless the group
as a single map unit was placed on the map almost all the way
from the river west to the county line. The area varies greatly
in width because in many places the greater part of the Giles has
. been eroded away from the Rockwood.

It seems reasonable to correlate No. 1 with Coeymans, No. 2
with New Scotland, No. 3 with Becraft and No. 4 with Oriskany,
but any such allocation is only tentative. No. 4 and Oriskany are
the most confidently connected. There is much less assurance
concerning the other three.

There seems to be an unconformity at the base of the Oriskany,
but the details of the occurrence or absence of different parts of
the Cayuga and Helderberg are not well known in this area.
It seems to the writers that future work here will justify a revi-
sion of the nomenclature of the lower Devonian which may re-
sult in at least three new division names for rocks which are at
present simply called Giles.

The Romney Shale

Overlying the Giles, there are in a few places in Giles County,
dark shales to which the name Romney has been given. These
shales grade insensibly from black carbonaceous shale, which is

354

HUBBARD AND CRONEIS

replaced by green, sandy shale, to rocks which in turn merge
into thin bedded green sandstones. Only the dark division is
called Romney, the upper portions being designated as Kim-
berling.

The true Romney shale at the type locality, Romney, W. Vir-
ginia, is reported to contain fossils of Onondaga, Marcellus, and
Hamilton age. The Romney of Giles County is thought by Stose
and Miser to be of Genessee and lower Portage time and there-
fore younger.^® At the base of the Romney, however, near Big
Stone Gap there have been found fossils of Hamilton and Mar-
cellus age in a thin layer of disturbed, rusty, black shale. True
Romney has been deposited, it would seem, but has almost en-
tirely been removed by erosion. The thickness of the so-called
Romney is about 500 feet.

Again, exposures in Clendenning Creek are clearly of Marcellus
age for they contain the following forms : Camanotoechia cf .
exemia, Stropholosia truncata, Leiorhynchus Umitare, Styliolina
fissurella, Tentaculites bellulus, and Ambocoelia umbonata.
These include forms said by Kindle^®^- to be characteristic of the
Marcellus. To continue, none of the forms said by H. S. Williams
to be characteristic of the Genesee have been found in the Nar-
rows section. Hence, the evidence from both sides seems to
point to Marcellus age for the Romney of Giles County.

The Kimberling Shale

As has been mentioned before, this formation passes from
greenish or gray fissile shale to sandstone and appears to be
about 3000 feet in thickness. Fossils, which are not numerous in
this form.ation, indicate Portage and Chemung age. The sand-
stone at the top may in part be Catskill although no flora or
fauna were found in this horizon.

None of the Devonian of Giles County presented outcrops
which could be subdivided easily since by far the greatest portion
of these rocks is shale which weathers very rapidly.

Stose, G. W. and Miser, H. D. Manganese Deposits of Western Virginia,
pp. 38.

Kindle, E. M. Jour. Geol. Oct.-Nov. 1906. Faunas of Devonian Sec-
tion near Altoona, Pa.

GEOLOGY OF GILES COUNTY, VIRGINIA

355

THE MISSISSIPPIAN SYSTEM

Introduction

The Mississippian formations, which are the youngest con-
solidated sediments of Giles County, appear only in the pan-
handle district. The base of the series is sandstone, which is
followed in turn by shales, limestones, more shales, and is, in
this area, terminated by the Hinton formation. The total thick-
ness in Giles County is less than 4500 feet, but it is very hard to
measure on account of the covered areas.

The Price Sandstone

Overlying the upper Devonian sandstones, there is a granular,
bluish white sandstone which contains scattered quartz pebbles.
This sandstone is continuous with one in Bland County (of ap-
parently the same age) which has been called Price by Campbell.^'^
In other parts of Virginia, a sandstone very similar to the Price,
and of basal Mississippian age has been given the name Pocono.
The writers believe that the two are of the same age and are a
stratigraphic unit.

No fossil plants or invertebrates were found in this division.

The Pulaski Shale

This is a bright red shale, which is usually brought in direct
contact with the middle Price due to the faulting out of the upper
portion of the latter formation. This, however, is not the case
in the Narrows section, and yet only a poor exposure of what was
thought to be Pulaski could be found, due again to the rapidity
with which those shales weather to cover themselves.

The Greenbrier Limestone

This formation is made up of heavy blue limestones, which are
sometimes cherty and always fossiliferous. At the top, however,
it becomes rather shaly and passes into a calcareous shale at the
base of the overlying formation. Several considerable sandstone
horizons also occur in the Greenbrier.

Paleontology and Correlation

Some of the more common faunal forms of the Greenbrier of
Giles County, as listed by Bassler and others, are given in the
list which follows :

Campbell, M. R. U. S. G. S. Folio No. 26.

356

HUBBARD AND CRONEIS

Spirifer increbescens
Eumetria marcyi

Zaphrentis spinulosa
Fenestella sp.
Archimedes sp.

Derbya crassa
Allorisma maxvillensis
Bellerophon sublaevis
Spirifer keokuk
Dielasma turgida

Seminula subquadrata
Seminula trinuclea

Productus fasciculus
Productus cestriensis
Pentremites godoni

Pentremites pyriformis

Professor Prosser and Dr. R. B. Rome collected a very similar
fauna from the Greenbrier of Maryland for the state survey.
The Maxville limestone fauna of Ohio is also very similar and
the Greenbrier has been regarded as the Appalachian equivalent
of the Maxville by Morse-® and others. This is no doubt in part
true, but the Greenbrier seems to include more than the Maxville.

The Greenbrier as Divided by Bassler-^

Probably the best and most detailed section of the Greenbrier
limestone to be observed in Virginia may be seen along the
Norfolk and Western Railroad near Lurich, in Giles County.
Here all of the beds are fairly 'well exposed and the section may
be considered as typical for the region. For this reason all of the
variations in the strata at this point were noted. The section
is, in ascending order, as follows :

Geologic Section, Greenbrier Limestone
Vicinity of Lurich, Virginia

7. Thin-bedded blue limestone with beds of blue and yellow
shale. 400 feet.

6. Compact blue to black argillaceous limestone in thin
flaggy layers, much fractured. 170 feet.

5. Compact blue-black, fine-grained limestone alternating
with coarsely crystalline fossiliferous strata, with blue limestone
and yellow shales in upper part. 150 feet.

4. Drab and blue shales. - 80 feet.

3. Massive blue and argillaceous limestone with a few shaly
beds in the upper part. No chert observed. 90 feet.

2. Drab and yellow calcareous shales with occasional bands of *
compact blue limestone. 180 feet.

Morse, W. C., “The Maxville Limestone,’’ Bull. 13, Series No. 4, Ohio
Geol. Survey, pp. 109-111.

^ Bassler, R. S., “The Cement Resources of Virginia,” pp. 275.

GEOLOGY OF GILES COUNTY, VIRGINIA

357

1. Dark blue to black, heavily bedded limestone with many
small chert nodules. Productm, Zuphrentis, and Fenestella
observed. 175 feet.

The Biuefield Shale

This shale, which directly overlies the Greenbrier, varies from
calcareous at the base to sandy at the top, where it is capped by a
heavy bed of quartzite. It marks the transition period between
the deposition of limestone below and sandstone above.

The formation takes its name from the town of Biuefield, West
Virginia, where it is typically developed, and attains a thickness
of 1250 feet. The section at the Narrows is also a little over
1000 feet in thickness. Some horizons are quite fossiliferous in
the vicinity of Rich Creek,

The Hinton Formation

This formation is composed of impure limestones, argillaceous
shales, sandy shales and sandstones, but it is so heterogeneous
that no bed may be mapped separately. It is especially well de-
veloped along the New River in the vicinity of Hinton, West
Virginia, from which place it takes its name. In Giles County
there are 1000 feet exposed, but the section is not complete.
There are several fossiliferous zones in this formation. The
calcareous beds are rich in flat coiled gastropods. Stigmaria and
Catamites are rather common in some of the divisions.

Tertiary Gravels

Mention must here be made of the Tertiary gravels which are
found even at considerable altitudes in the open valley between
Butt and Angels Rest mountains. Some of these deposits occur
at elevations as much as 350 feet above the present river bed.
The exact status of these deposits is in doubt, but they may in
part correspond to the Lafayette or Orange Sand formation of
Oligocene time, which is found in many of the states just to
the west of the Appalachians. This formation often has a
thickness of twenty to thirty feet and is composed of sands,
gravels, and even rounded boulders. It was derived from the in-
soluble residue of older formations such as chert and quartzite
pebbles, together with limestone fragments side tracked by the
streams before wholly ground up. The color is often yellow or
orange, and the deposits are quite conspicuous occasionally for
long distances. This deposit was formed by peneplanation and

358

HUBBARD AND CRONEIS

subsequent weathering of the land surfaces during the later
Tertiary, producing a layer of loose, insoluble materials. As a
result of the several rejuvenations discussed on early pages, the
streams could carry more detritus which was dropped on reach-
ing lower levels. This process was repeated again and again
with subsequent uplift and erosion. The sediments now are
removed from places which have been subjected to severe ero-
sion but are nearly always present in places where streams are
too weak to handle the residue. Especially is this true in the
Pearisburg area where underground drainage takes care of so
much of the water, that surface erosion is lagging far behind
subsurface weathering.

STRUCTURAL GEOLOGY

The sedimentary rocks of this county have been extensively
folded, and these folds have their elongated axes roughly parallel
and trending east by northeast. Many of the upper layers have
been worn away by erosion, so that narrow, parallel belts of out-
crops, trending in the same direction as the folds, are the com-
mon thing. Harder rocks, such as sandstones and quartzites,
have resisted erosion and hence are the mountain makers. The
valleys between them are usually carved in softer or more soluble
strata, such as shales or limestones.

The folds are, for the most part, continuous and may be traced
for miles. The same may be said of the faults, which closely fol-
low the axis of greatest folding.

Folding has tended to increase the thickness of the formations
along the crests of the structures and, as a consequence, added
strength has been given, so that the formation may take up still
more of the stress. These beds are, of course, competent, such
as the Clinch, Shenandoah, etc. Non-competent beds, such as
the Sevier and the Russell, develop smashed, intensely folded
areas between the stronger layers. Drag folds become pro-
nounced and small displacements and shearings are common.

The big Peters Mountain fault runs along the north edge of
East River and Peters mountains, just outside of Giles County,
and brings Cambro-Ordovician rocks in contact with upper De-
vonian strata. A smaller fault parallels the East River-Peters
Mountain break, and runs north of Wolf Creek. It crosses New
River just above the rapids at Narrows and proceeds eastward.

GEOLOGY OF GILES COUNTY, VIRGINIA

359

passing just north of Kimballton. It seems to be a single fault
east of New River but westward it is generally in two steps. In
this paper, this fault will be called the Wolf Creek fault. Near
the Narrows, Giles and Romney rocks are brought by this dis-
placement in contact with the Shenandoah limestone.

The Saltville fault parallels the southern boundary of the
county. It runs through Poplar Hill, Staffordsville, and a little
south of the crests of Buckeye and Spruce Run mountains. Every-
where on the southerly side of the fault is the Shenandoah lime-
stone, but on the north, there are Ordovician, Silurian and even
Devonian rocks in various places. It seems to be a two-step fault
in Buckeye Mountain.

All of the above mentioned faults are of the thrust type, and
in each case the older rocks were thrust over younger ones from
the southeast. The dips, then, on the southerly side are regularly
south-south-east ward, rarely more than 25° in the case of the
Saltville fault, and seldom exceeding 35° in the other two previ-
ously mentioned breaks. Other faults of Giles County are of
the normal type, and are too small to be named, being ordinarily
confined to a single member of one formation, with displacements
of less than fifteen feet.

Walker Mountain is formed by the upturned edges of the
Clinch and Bays formations to the south of the Saltville fault.
Buckeye and Spruce Run mountains are formed by the up-
turned and south dipping Rockwood, Clinch and Bays on the
north side of Saltville fault. The crests are on the south limb of
an anticline whose axis lies just north of them. In their south
slopes these mountains still preserve enough structure to show
that they are the remnants of a syncline which was broken by the
fault. Thus the strata on the south side of the fault were thrust
up many hundreds of feet so that Shenandoah lies against Rock-
wood and Clinch. This displacement carried the south limb of
the syncline and the succeeding anticline (whose axis was be-
tween Buckeye and Walker mountains) so high that they were
all eroded in the pre-peneplain periods of erosion (probably early
Mesozoic time). Walker Mountain, then, is the southern limb
of the anticline with the strata dipping away to the south.

Pearis and Angels Rest mountains are opposite sides of a
synclinal structure pitching off to the west by southwest, so that
Mill Creek is flowing in an erosion widened, structural valley.

360

HUBBARD AND CRONEIS

Butt Mountain is another part of the same structure pitching in
the opposite direction, east by northeast. Between these two
summits the structure was so high in pre-peneplain times, that
the hard layers, Rockwood and Clinch, were eroded off together
with the less resistant ones down to the Shenandoah and Chicka-
mauga limestones. New River found its way across the struc-
ture at this place. The roots of the syncline can still be seen in
these rocks in the vicinity of Ripplemead.

The limestones making up the valley areas are of course in-
fluenced by the above discussed structures, yet in most places the
dips are not extreme. However, north of Bane, where the anti-
cline between Pearis Mountain and Buckeye Mountain is folded
highest, there is an area where many small pronounced structural
features occur, but these have previously been discussed under
the heading of the Russell formation.

Sugar Run Mountain and Pearis Mountain converge toward
Flat Top Mountain because they stand up on account of the hard
layers in the above discussed anticline, which is pitching steeply
westward. Flat Top is then the descending crest of this struc-
ture as it goes down carrying on its summit Clinch, Rockwood,
Giles, Romney and Kimberling.

ECONOMIC RESOURCES
Coal

Giles County may be regarded as a block of older Paleozoic
strata separated from younger rocks, on the north, by the Peters
Mountain fault, and on the south, by the Walker Mountain fault.
For this reason, coal is not found in Giles County, although semi-
anthracite coal of good grade is mined but two miles to the south
of the Walker fault, in the Cloyds Mountain area of Pulaski
County.

Oil and Gas

The possibility of finding either oil or gas in the rocks of Giles
County is remote, indeed, and so far as could be discovered there
has been no drilling for either of these products.

The strata of this area are so deeply dissected, so complexly
faulted and mashed, and so intensely folded that any oil or gas
once imprisoned has long since escaped. ' However, since none of
the residual products of the natural distillation of hydrocarbons
are found, it is doubtful if they were ever present here. *

GEOLOGY OF GILES COUNTY, VIRGINIA

361

Manganese-^

Historical Sketch

The manganese deposits of Virginia have been worked at vari-
ous times since 1834. However, previous to 1917, no work of a
commercial nature was attempted in Giles County. In this year,
the Stange mine was first operated and various other smaller
prospects in the county were exploited, due to the increased de-
mand for domestic manganese ores on account of the War.
When the armistice was signed, work ceased at once on most of
the mines, but the Stange prospect was operated until June 1,
1919. This mine, which is one of the most important in the
state, is no doubt the prospect described by Boyd’^ some forty
years ago as follows :

“Manganese ores seem to be confined almost exclusively to the
Oriskany measures. In fact, the iron ore of these rocks fre-
quently gives way almost entirely to oxide of manganese.

“At one point in these rocks on Flat Top Mountain, near the
line between Giles and Bland counties, the ore was found in
great purity, giving the following measures, etc. : Trend north
70° east, dip 60° north 20° west, containing valuable quantities
of manganese disseminated heavily through the sandstone, five
hundred yards in length, gradually becoming impregnated with
iron as you approach the eastern end. The apparent width of
the ore strata here is extraordinary, and may be owing to a
duplication of strata from end pressure, or flexure, or a mere
fold. It is 240 feet through. Elevation above the water level
in Kimberling Creek is 1200 feet ; vein would no doubt strip well.

“Analysis of Manganese Ore as follows :

“Red oxide of manganese^ (Mn203 ?) 84.34 (a)

Oxygen (0) 3.73 (a)

Protoxide of Cobalt (CoO) 68

Alumina (Al.Og) : 1.80

Lime (CaO) ' 32

Silica (SiOg) 21

Baryta (BaO) 7.21

Water (H^O) 1.71

(Signed) H. Dickinson.’'

The material incorporated under this heading has been derived in part
from Bull. No. 23 of the Virginia GeoL Sur. by Stose, G. W., and Miser,
H. D. and also from private sources of information.

“ Boyd, C. R., “Resources of Southwest Virginia,” pp. 147-148. John
Wiley and Sons, New York, 1881.

362

HUBBARD AND CRONEIS

This description, even in the light of present knowledge, may
be regarded as a very good one, and to Boyd must go the credit
for first mentioning the manganese deposits of Giles County, at
least, in writing.

It may be interesting to digress here long enough to mention
the method of discovery of the value of manganese in the manu-
facture of heavy ordnance pieces. According to Judge Bernard
Mason-^ of Pearisburg, many of the large guns used by the
South, in the Civil War, were made from iron ore obtained from
Giles County and vicinity. This ore contained some manganese,
but this fact was either unknown or disregarded by the manu-
facturers. The fact that the southern canon stood up better
under heavy service was known, however, and the war being
over, an investigation was made. The results showed that man-
ganese had imparted extra strength to the steel.

The Stange Mine

The Stange mine has marketed slightly more than 2000 tons
of ore during the course of its operation. The workings are on
and near the crest of Flat Top Mountain, and the boundary be-
tween Giles and Bland counties actually passes through the mine.
There are three principal cuts : the North cut, which is on the
north side of the crest, trends east and west, being about 250
feet long by 60 feet wide and 30 feet deep. The South cut is
600 feet in length and follows the face of the mountain. The
Middle cut runs northeast from the South cut about 150 feet and
is some 40 feet in width by 20 feet in depth.

The veins and pockets of ore vary greatly in size, the ore
being distributed through all the sandstone revealed in the
openings, but very unevenly. One ton of ore of market grade
can be derived from four to five tons of the ore-bearing sand-
stone.

The ore as mined by B. T. Johnson and sons, as well as by Mr.
Suffern, was either picked up on the surface or mined by hand in
open cuts and was then hand-picked for marketing.

Mr. Stange later operated the mine by means of a steam shovel,
and then hauled the ore more than a mile to the washing plant
on Ding Branch of No Business Creek. The plant consisted of a
double log washer and a picking belt. After the ore was run

Private conversation.

GEOLOGY OF GILES COUNTY, VIRGINIA

363

through the washer, the concentrates were hauled in trams
from the plant to the base of Wolf Creek Mountain. From this
point, the ore was carried to First Ford station by means of an
incline railroad. Here, it was transferred to standard cars for
shipment. Of necessity, this transportation method greatly in-
creased production costs.

The deposit is in the Giles sandstone which is probably of
Oriskany age. The sandstone appears on the surface as well
as in the workings. There are pockets of ore and sandstone
fragments up to ten feet in width, which extend down to some
twenty-five feet. These are thought to be zones of fissuring in
the anticlinal arch of sandstone, which have become impregnated
with ore formed by the accumulation of residual materials in
the fissures as the rock weathered.

Scattered masses of ore at the surface indicate that the de-
posit extends east and west some nine hundred feet and north
and south a little over three hundred feet. A drill hole seventy-
two feet in depth is said by Mr. Stange to have found the ore
continuous at least to that depth. The minerals are manganite,
pyrolusite, psilomelane, the last named being most common at
the surface. Pyrolusite is the chief mineral found at depth. It
is of a fine grade, suitable for metallurgical purposes. The mine
has by no means been exhausted, and future developments may be
expected as soon as present transportation difficulties are over-
come.

Other Prospects

No other prospect for manganese in Giles County approaches
the Stange mine in size or possibilities. Pyrolusite float can be
found here and there almost any place in the county. On account
of this fact, when the war boosted manganese prices, attempts
were made to develop a number of prospects which were without
commercial value.

Laing Prospects

This prospect is two miles northeast of the village of Newport.
Newport is a village in the southeast corner of Giles County, a
mile south of Sinking Creek and 7-8 miles east of Eggleston.
A group of openings has been made on a hill top about a mile
north of Sinking Creek. The elevation is 2600 feet and seems
to mark the level of a former peneplain, now largely destroyed.
The prospect is underlain by Shenandoah lime (Knox dolomite

364

HUBBARD AND CRONEIS

of StO'Se and Miser) and the ore is in the residual clay and chert
of this formation. An overthrust fault here has brought these
older rocks in contact with sandstones of probably Oriskany age
which appear a little higher on the mountain side. Very little
actual work has been done here.

Simpkins Prospects

This prospect is two and one-half miles west-north-west of
Interior Station on the Potts Valley branch of the Norfolk and
Western Railroad. This branch leaves the main line about a mile
below Ripplemead and runs up Stony Creek past Kimballton
almost to the northeast corner of the county. The openings
are on the crest of a spur of Peters Mountain at an elevation of
2800 feet, and the ore appears to be in the fractured zone of the
southwest end of the local syncline. The formation in which the
ore is found is the Giles, which is here a buff colored, much frac-
tured sandstone. Psilomelane is the ore. Transportation facil-
ities are good since the prospect is less than a mile from the rail-
road, but there is not enough ore in sight to warrant exploitation.

Stowe Mine

This mine is on the southeast slope of Piney Mountain, four
miles to the southwest of Narrows on the Norfolk and Western
Railway. The openings are all shallow pits, on or near the
surface of a bench which is 2400 feet in elevation. This probably
represents the old valley floor peneplain of the New River System.

The ore is in shaly sandstone and clay which appears to be of
Giles age. About fifty tons of ore, running 32% manganese have
been taken from the mine. This mine can only be worked at a
profit when the demand for manganese is greatly increased.

The Bane Prospect

This prospect, which lies just south of Walker Creek at Bane,
seems to be little known. However, this prospect is probably the
only one in the county (the Stange mine excepted) which has
possibilities favoring development in the future.

The ore, which occurs in the residual clay and chert overlying
the Shenandoah limestone, is pyrolusite. The area over which
the ore appears on the surface cannot be less than forty acres,
and, according to local information, several small pits found
the ore not decreasing in quantity at a depth of five feet. The

GEOLOGY OF GILES COUNTY, VIRGINIA

365

surface mantle of soil and chert contains the ore, hence a wasner
would be necessary to prepare the manganese for market.

The nearest point where shipment could be made, is Pearis-
burg Station, which is some eight miles distant, too far to war-
rant exploitation at present. However, should a railroad be run
up Walker Creek Valley, this prospect would at once become of
considerable value, since the quantity of ore is large and can
easily be worked by steam shovel.

The Hare Prospect

This prospect is one and one-half miles north of Chapel Sta-
tion on the New River, Holston and Western Railroad. Two
openings have been made, both in the Oriskany member of the
Giles,' which are about forty feet long by eight feet wide by
fifteen feet in depth. Some psilomelane has been mined but the
sandstone has been only partially replaced by this mineral and
brown iron ore. The latter may become of importance since a
pit farther north reveals the ore to be some fourteen feet thick
in the Rockwood formation.

Other Locations

Manganese is also reported from many other localities. The
Reamer prospect is about a mile east of the Hare prospect men-
tioned above. No Business Creek prospect is three miles south
of Chapel station over Wolf Creek Mountain and while little
work has been done here, surface indications suggest a consid-
erable deposit of manganiferous iron ore. Other prospects, sim-
ilar in nature to the Stange mine, occur farther to the east of
this deposit on the same ridge. The Johnson prospect and the
Thompson place are both Flat Top prospects somewhat more
than a mile to the northeast of the Stange mine. In both places,
the ore is low in grade and occurs only in small amounts. How-
ever, some twenty-five tons have been shipped from the Johnson
mine.

Manganese float is also found in Short Mountain, in the vicin-
ity of Narrows, in the Doe Mountain region, near Newport, and
in the Spruce Run Mountain tracts. These prospects have not
been exploited and if any ore has been shipped, it has been hand
picked from the float appearing at the surface and is almost neg-
ligible in quantity.

366

HUBBARD AND CRONEIS

The Origin of Manganese Ores in Giles County
The important manganese deposits of Giles County occur in
clays, sandstones and cherts. Chert, in the Shenandoah, is often
stained black by the oxide of manganese which in some cases
is present in sufficient quantity to warrant the name of ore.
Chert which has been broken into small fragments is often re-
cemented with manganese oxide or even replaced by it. Both
the chert and the manganese, being relatively insoluble, have been
left behind as residual products of the weathering of the lime-
stone. Some of the deposits are near fault contacts, the con-
centration being due to the free circulation of ground water in
the brecciated zone. However, if we except the deposit near
Bane, described above, prospects in the Shenandoah are small
and of no great value ; in fact, the only mine of this type which
has been worked in the county is the one near Newport. It is
rather interesting to note that, so far as could be ascertained,
ore of this type occurring in the residual clays of Giles County
does not show any evident connection with the chert found in
association. The connection, however, is obvious in the deposits
of the other counties in southwest Virginia.

In Giles County by far the largest deposits of manganese
occur in sandstones of the Giles formation or in the unconform-
ably underlying Rockwood sandstones. Crests of anticlines seem
to be the favored position for the accumulation of these deposits,
due to the fact that these resistant beds, when bent, developed
fractures wherein ground water could easily circulate.

Many of the prospects are unique in that they occur on Moun-
tain tops, such as the Flat Top Mountain prospects. Obviously,
segregation must have taken place when the present elevation
of some 3000 feet was part of a peneplain which was not very
high above sea level. Other deposits occur on benches on the
flanks of the main ridges. These also were segregated when
the present elevation was but a part of a smaller, and later
peneplain than that which was developed in Cretaceous time.
Of the bench type are the Carrie, Laing, Simpkins, and the
Spruce Run Mountain prospects mentioned above.

The association of these ores with particular formations seems
to indicate that the manganese was deposited in greater quantity
in certain beds than others, yet only disseminated thinly; and
that it has been concentrated into its present state, by solution

GEOLOGY OF GILES COUNTY, VIRGINIA

367

and redeposition by circulating ground waters as the rocks
weathered.

The manganese ore of the Shenandoah was probably widely
scattered in the basal portions, originally as a carbonate. Here
it was dissolved by ground waters. Solution channels, caving,
or folding caused brecciated zones, in which the ore was rede-
posited in a concentrated form. The interstices were thus filled
with ore, and the silica of the chert was in some cases partially
replaced by the manganese oxide.

In a similar manner, the ore which is found in the Rockwood
and Giles formations was originally disseminated in the basal
Giles. The manganese was concentrated by descending, circulat-
ing waters and deposited as the oxide near the bottom zone of
surface weathering.

The Oriskany iron ores of Virginia have been regarded by
Watson-'^ and Holden^® as having been derived from the iron
bearing minerals in the Devonian shales overlying the Oriskany.
These minerals were dissolved by carbonated waters during
weathering and redeposited in lower levels. Watson suggested
that the manganese deposits in these rocks might have had a
similar origin. Accordingly, he collected a sample of unaltered
shales which overlie the manganese of Bland County to deter-
mine the absence or presence of manganese. Although the
analysis showed 4.54 per cent, iron oxides, no manganese was
found.

The absence of manganese in the particular sample of shale
collected has been thought to have made this theory untenable.
However, despite this fact, we are inclined to the opinion that
at least some of the manganese was originally disseminated in
the overlying shales as well as in the sandstones of the Giles
formation. The reasons for this view may be stated as follows :
first, some of the deposits occur well up in the Giles sandstone,
so that derivation, in entirety, from the same formation is rather
unlikely, and, second, if the iron deposits which are so wide
spread in the lower measures are derived from the Devonian
shales, whose analysis shows but 4.54 per cent, iron oxides, might
not the manganese, whose quantity is negligible in comparison
with that of the iron, have, at least in part, the same source, and
yet not be detected in the analysis, especially, of a single sample ?

Watson, T. L., “Mineral Resources of Virginia,” pp. 408-410, 1907.

Holden, R. J., U. S. Geol. Survey Bull. 427, pp. 67-68, 1910.

368

HUBBARD AND CRONEIS

Iron

Iron ore has been mined in Giles County, and will, in the
future, constitute a more important economic resource than it
has in the past or does at present. The ores may be divided into
three classes : Those found in the Oriskany horizons, the Clinton
or Red fossil ore of the Rockwood and the ores found in the
lower Paleozoic limestones.

The Brown iron ore is the type usually found in the Oriskany
measures. Boyd-'^ estimated that ten per cent, of these rocks
were iron, but the deposits are of such a local nature that this
estimate seems much too high. The most conspicuous beds are
found on Buckeye, Butt, Salt Pond and Flat Top mountains.
There is also a large deposit on Wolf Creek Mountain, which
Boyd thought would yield 300,000 tons of ore, which would
run over sixty per cent, metallic iron. Boyd was rather
prone to exaggerate and but little has been mined here. At
Interior, some mining of Brown ore in Oriskany measure has
recently been done, and since the railroad has solved transporta-
tion problems, it seems likely that more ore will be mined in
the future, as the reserves here are quite large.

The source of these ores has been explained in the discussion
of the Stange mine. The Devonian was a period during which
much iron was deposited,-® as is shown by the fact that shales
overlying the Oriskany sands will run five per cent, iron con-
tent. The concentration of these ores in fracture zones in the
lower sandstones is thought to be the origin of the local Oriskany
ores.

Hematite ore is found in the Clinton (Rockwood) formation
wherever it is exposed in Giles County. The ore is usually the
richest in the lower layers just over the Clinch. This is especially
true where the Rockwood is the ridge maker, as in these cases
the iron of the upper layers has been leached out and concen-
trated in the fractured lower layers, which overlie the nearly
impermeable quartzite below.

The ore is both fossil and granular in type. The fossil ore is
made up of aggregates of broken fossils, which were originally
calcium carbonate, but which have now been replaced by ferric
oxide, some of which was always present in the formation, prob-

Boyd, C. R., “Resources of Southwest Virginia,” pp. 144.

^ Emmons, W. H., “Principles of Economic Geology,” pp. 295.

GEOLOGY OF GILES COUNTY, VIRGINIA

369

ably filling cavities. The granular ore (which is usually sub-
ordinate to the fossil type) is made up of aggregates of quartz
grains like fiaxseed in shape, about which the iron oxide has been
deposited. In the Clinton epoch, iron was deposited in large
amounts throughout much of eastern North America. This ore
was carried in solution as bicarbonate in the presence of carbon
dioxide. When the excess carbon dioxide was removed, ferric
hydroxide was either precipitated due to oxidation and hydroly-
sis, or on account of the iron bacteria, which according to
Harder^® are always active in its accumulation.

The Bays Formation (Upper Ordovician) is often ferruginous,
and Bassler has suggested that at least some of the iron of
the Clinton is due to the erosion of the Bays, together with the
solution of its iron content, and its subsequent concentration in
the Bockwood. In a like manner, much of the Devonian ore may
be due to the erosion of the Rockwood and the later deposition of
the iron content in the Giles sandstones and shales.

The deposit of this type of ore over the entire flat summits of
Angels Rest and Pearis mountains may sometime be developed.
There are many thousands of tons of poor grade ore in this de-
posit which might be mined by steam shovel. The small iron
content and the lack of any facility to get the ore down off the
mountain prevents the exploitation of this ore body.

Many of the Brown ore deposits in the Cambro-Ordovician
limestones appear to have been formed rather recently, probably
during Tertiary times. (Tertiary fossils have been found in
these deposits.)^® These ores are alteration products of iron
carbonate and pyrite, which in turn originated by replace-
ment of the limestone. The ore often is found filling fissures
and concentrated in fracture zones. From the structural posi-
tion of many of the ore bodies, it seems evident that the deposits
were made when the country had reached a topographic state
not vastly different from that existing today.

The best exposures are at Johnson’s near Chapman’s Ferry,
and at the mouth of Big Stony Creek. Scattered out-crops of
this ore are found over the entire county. Usually the strati-
graphic position of the ore is near the contact of the Shenandoah
with the Chickamauga.

Harder, E. C., “Iron-depositing Bacteria and their Geologic Relations,”
U. S. Geol. Survey Prof. Paper No. 113 (1919).

Eckel, E. C., U. S. Geol. Survey, Bull. 400, pp. 145.

370

HUBBARD AND CRONEIS

Thus while the county has a good deal of iron ore and much
more ferruginous rock which may some day be leached to make
valuable ore, yet there is really no deposit of iron ore known
that can compete with the producing regions of the United States.

Limestone and Cement

The limestones of Giles County are of great importance since
they may be used either in the manufacture of lime or cement,
or as building or road making stone. The New Eiver Lime
Company has a quarry to the northwest of Ripplemead, along
the river, from which is taken some forty car loads a day. Clay
Mason has a considerable lime making establishment across and
a little upstream from this quarry. At various times, the lime-
stone has been used in other places but the industry has not
been developed nearly to the limits of its possibilities. Cement
could be manufactured quite to advantage here, since the Chicka-
mauga exposures are all well served by railroads, and the neces-
sary shale is usually found close at hand in the Sevier formation.

Clays and Shales

These are of little importance here and have not been exploited.

Sands and Gravels

These belong in the same category as the above list. Some
sand is taken from the New River for local use, but it promises
no importance. Tertiary gravels occur, but are of little use, be-
ing composed of large boulders, of cobble stone size, for the
most part.

Water Supply

As would be expected in a mountainous, limestone area, re-
ceiving considerable rainfall, there is an abundance of water.
This supply is very liable to contamination, however, on account
of the great development of under-surface drainage. There are
several places along the New, where water power could be ob-
tained by tunneling, but an abundance of cheap electric power,
due to the nearness to the coal fields, has so far, hindered this.
Sulfur and mineral springs occur at Eggleston and at other
points.

GEOLOGY OF GILES COUNTY, VIRGINIA 371

Soils

For the most part in this area, the soils and the rocks from
which they are derived, are equally differentiated, so that the
areal map may be followed with considerable accuracy. The
sandy soils derived from formations such as the Bays and the
Clinch are of no importance for agricultural purposes. For the
most part, shale does not disintegrate into a fertile soil; how-
ever, the Sevier shale contains enough calcareous material to
make it quite productive. This formation, however, usually out-
crops so high and on such steep slopes that it ordinarily cannot
be used. The Chickamauga ranks the highest as a soil producer
and is responsible for the rich farming lands of the Pearisburg
area. The Shenandoah limestone also disintegrates into a fairly
fertile soil but it also leaves behind it a mantle of the insoluble
chert which makes cultivation difficult, but not impossible.

No doubt the soils of the county constitute, at present, the
most valuable geologic resource available.

RESUME OF GEOLOGIC HISTORY

As has been mentioned in the introduction, the area under dis-
cussion lies in that division of the Appalachian Highlands,
known as the Appalachian Valley Province. Giles County is sit-
uated at the extreme southern end of the Middle Section of this
province. In northwestern and in the central western portions
of Virginia, there is no great difference in the stratigraphic suc-
cession or in the lithology of the Ordovician and Silurian strata.
In the area comprising most of southwestern Virginia, however,
a new factor is introduced in the study of these same rocks.
Ordinarily, rocks deposited synchronously in comparatively small
areas exhibit no great differences either in fossil fauna or in
lithologic aspect. In the division of the state mentioned above,
the rocks differ in different areas, in both of these respects. In
the eastern portion of the great valley, the development of the
Ordovician strata is entirely different from that found in the
westernmost portions of the state. In studying the various sec-
tions, these discrepancies in apparently the same age of strata
are encountered in traverses made across the valley rather than
in directions paralleling the length of the valley.

Physiographic Divisions of U. S. Ann. Assoc. Amer. Geog. Vol. VI.,
pp. 19-98.

372

H.UBBARD AND CRONEIS

The theories for this distribution of strata in separate areas
will not be developed in this paper any more than to mention that
Ulrich and Schuchert,^- in their Paleozoic Seas and Barriers,
have advanced the well founded idea that the area of the Appala-
chian Valley during Ordovician times was divided longitudinally
into several narrow troughs, which were rather effectually sep-
arated, one from the other and that the observed differences in
sedimentation and faunal life may thus be explained.

The area covered in this survey lies entirely within a single
one of these “troughs” but as one ascends the New River and
comes to the Giles-Pulaski County line, there is noticed at
once a marked difference in faunal life and lithologic aspect.
The details cannot be discussed here but it might be interesting
to note that the Clinch formation in Cap Mountain, is composed
of three distinct quartzitic ripple making layers, while at the
Narrows, a scant twelve miles to the west, there are but two of
these layers and one of these is not distinct.

The Appalachian series of folds, probably trace their origin
to pre-Cambrian times. Walcott^'^ demonstrated the existence of
a long trough, which during Lower Cambrian times extended
from Alabama northeast to Labrador. This was no doubt what
we would call a geosyncline and was within the southeastern bor-
der of a large Algonkian continent. It was during this time, that
the impure limestones and variegated shales of the Russell forma-
tion were deposited. At varying intervals, the seas were deep and
then again they were shallow, until in Middle Cambrian time, the
Appalachian trough was almost drained of its sea. However,
long before the close of this epoch, a new period of subsidence
was inaugurated, and the sea became gradually deeper until in
Upper Cambrian time it was beyond the Adirondacks and had
made connection with the Atlantic by way of the restricted
Appalachian trough.

For the most part, the Upper Cambrian seas laid down great
beds of limestone, which are usually dolomitic and non-fossi-
liferous. These facts seem to indicate that the Shenandoah lime-
stone, which was laid down at this time, was deposited at a
considerable distance from the shores and in waters which were
of a considerable depth. Chemical precipitation will be regarded

Ulrich, E. O. and Schuchert, Charles, ‘‘Paleozoic Seas and Barriers in
Eastern North America.” N. Y. State Museum Rept., Bull. 52, pp. 633-664.

Walcott, C. D., U. S. Geol. Surv. Bull. 81.

GEOLOGY OF GILES COUNTY, VIRGINIA

373

as the main source of the material which composes it. Be-
tween the limestones of this time and those of Beekmantown age
in the area under discussion, the difference is very slight and it
must be regarded that the sedimentation went on almost unin-
terupted from the beginning of the Upper Cambrian to the close
of the Beekmantown. We will regard the deposition of the Shen-
andoah limestone, then, as having taken place during this inter-
val. The close of the Beekmantown marks the beginning of a
new arrangement in Eastern North America.

A new fold was developed, nearly parallel with, and a little
within the western border of the original Lower Cambrian
trough and another fold, mentioned before as having emerged
early in Middle Cambrian time, was accentuated. Between these
two folds, a trough was formed which extended from Alabama
to Quebec. It is doubtful, however, if this trough was ever again
completely submerged after Beekmantown time. Ulrich and
Schuchert have named the western one of these two folds, the
Appalachian Valley Barrier, and the eastern one was named the
Chilhowee Barrier. The Lenoir bay, which was the southern
third of the space between the two folds, occupied a synclinorium
containing several disconnected folds, which were high enough
to affect the direction of currents, and consequently the char-
acter of sedimentation. In a general way, these deposits may be
divided into an eastern trough (Athens trough) and a western
one (Knoxville trough). The members of each overlap or grade
into each other on account of differential warping.

The area under discussion lies in the Knoxville trough. The
development of the Chickamauga limestone here indicates that
there was at the time of deposition of its bottom layers enough
warping to permit portions of the older Shenandoah to be sub-
jected to erosion. The breccia which goes to make up the lower
layers of the Chickamauga formation in this area is made up of
angular fragments of chert which is identical with that found in
the Shenandoah of today. That this chert in the breccia was de-
rived from the older formation is evident and that it was carried
but a short distance is evidenced by the fact that the fragments
are always angular and in the upper layers of the breccia are
seldom in contact one with the other.

The Chickamauga of this area, that is, of the Knoxville trough,
contains a fauna wholly distinct from that of other Chickamauga

374

HUBBARD AND CRONEIS

series, one of which has its greatest development in East Tenn-
essee. In this (the Pearisburg area) locality, however, the
Chickamauga embraces every important member of the forma-
tion as developed in Tennessee. There is evidence of only a
small unconformity between this formation and the Shenandoah,
and yet, if we have correctly correlated these strata, a consid-
erable time break exists. This is no doubt represented in part
by the breccia described above.

Following the Chickamauga is the Moccasin limestone, which
is calcareous near its base, but which becomes very arenaceous
near the top. This formation is clearly a gradational one repre-
senting the time between the deep seas in which the Chicka-
mauga was deposited and the shallow seas wherein the Bays
was laid down. It is due no doubt to the gentle uplift which
began in the time just preceding the early Trenton. In the east-
ern trough we have, as the equivalent of the Moccasin, the Tellico
sandstone. After this time, the Sevier formation was deposited
quite uniformly in both troughs. The Sevier in its various divi-
sions is equal to the upper Utica, and the Eden, and as would be
supposed, grades from calcareous at the base to arenaceous at
the top. The Sevier (as well as the Moccasin) may be regarded
as an intermediate formation fore-running the Bays.

At about the end of the Trenton, the troughs were elevated
quite rapidly and as a consequence, communication with the
Atlantic was cut off at the south where the elevation was the
greatest. At the same time, the middle portions of the Lenoir
Trough sank and permitted the waters from the Mississipian
sea to invade. The result of this revolution is the Bays and
Clinch sandstones as well as the lower and non-ferruginous shale
members of the Rockwood. The southern end of the trough con-
tinued to be uplifted as is shown by the fact that of the three
mentioned formations, the Bays extends farthest to the south,
the next, not quite so far and the third, the Rockwood, falls still
short of the Clinch. In spite of the fact that there is an uncon-
formity between the Rockwood and the Giles, (indicating uplift
and erosion in Giles County) when Devonian sediments were laid
down, the seas were again deeper in this area than off to the
south. This is clearly shown by the fact that these sediments are
but 25 feet thick at Chattanooga yet are nearly 5000 feet in thick-
ness on the New River.

GEOLOGY OF GILES COUNTY, VIRGINIA

375

Mississippian and Pennsylvanian rocks were laid down in
Giles County, but have been subsequently eroded. There is no
direct evidence for making this assertion, but Pennsylvanian
rocks are found on either side of the county, and since faulting
has so raised the entire area that Shenandoah lime is in contact
with Kimberling shales, there has been every opportunity for
erosion to have removed these later Paleozoics.

After this time, the uplift was rather steady and Giles County
becomes a land mass. Folding and faulting were not pronounced
in the Mesozoic, and by the end of this era a great peneplain had
been reached. However, in Oligocene time upwarping began
along the Appalachian axis and continued throughout the epoch.
As a result, the stream gradients were increased and erosion
began apace. As a result, the Tertiary Gravels were deposited in
those areas where the stream currents were abruptly checked.
The uplifts in the several periods of movement were continuous,
but gradual, as is evidenced by the fact that the New River has
been able to maintain its course through the ridges which are
due to the hard layers.

The rocks of Giles County suffered no close folding during
the Paleozoic because, while unconformities can be found, the
angular type is inconspicuous. There are no typical continental
deposits in the county unless we except the Tertiary Gravels
mentioned above. The Clinch has been regarded as a delta de-
posit and its shape and lithologic character in many areas seem
to confirm this view. Here, however, the presence of a marine
fossil, (Lingula cuneata) as well as shaly layers indicates that
the formation is at least semi-marine, and if it is a portion of a
delta deposit, it is the extreme outer edge of such a formation.

Mud cracks are common in many of the formations showing
shallow seas, yet marine fossils are also found in these same hori-
zons. Rapid changes of conditions are shown by the presence, in
some places, of limestone breccias, as well as fissile shale partings
in the great limestones.

The chert in some of these limestones seems to be a surface
feature, as deep quarries run out of the chert zone. The presence
of chert everywhere in deep caverns may or may not be regarded
as an additional proof of the surface character of the chert.
Calcite is also secondary in these limestones and is regarded as
Mesozoic or Tertiary in age, having formed everywhere in the

376

HUBBARD AND CRONEIS

fractures developed in the competent limestones during the time
of folding. That it is younger than the chert, is often shown in
specimens where the chert, as well as the limestone, has been
cut by a calcite vein. Hence some of it must be very recent.
The age of the iron ores has been discussed, but it may be added
that they sometimes seem to be both secondary and primary.

In conclusion, it should be said that this paper has but merely
touched upon the geology of Giles County. Scores of problems
stand out boldly bidding for solution, while many others lie half
concealed and shyly invite attention. Not the least of the prob-
lems available are those connected with the ancient life. In this
area, the fauna is different from the fauna in the next county to
the south. The comparison of the development of contempor-
aneous life in isolated basins, which are yet not far distant from
each other, may go a long way in the solving of some of the
problems of evolution. When this work is at last undertaken,
the area about Giles County will be a geologist’s “happy hunting
ground.”

BIBLIOGRAPHY

Bassler, R. S. Cement Resources of Virginia, West of the Blue Ridge.
Virginia Geological Survey, Bulletin No. 2-A.

Cement Materials of the Valley of Virginia. U. S. Geological

Survey, Bulletin No. 260, 1905, pp, 531-534.

Portland Cement Resources of Virginia. U. S. Geological Survey,

Bulletin No. 243, 1905, pp. 212-323.

Cement and Cement Materials. Mineral Resources of Virginia,

1907, pp. 86-167.

Cement Materials of Western Virginia. Economic Geology, 1908,

Vol. III., pp. 503-524.

Boyd, Charles R. The Mineral Resources of Southwestern Virginia. Wiley
and Sons, New York, 1881, 381 pages.

Campbell, H. D. The Cambro-Ordovician Limestones of the Middle Portion
of the Valley of Virginia. Amer. Jour, Science (4), 1905, Vol. XX,
pp. 445-447.

Campbell, J. L. Silurian Formations in Virginia. Amer. Jour. Science
(3), 1879, Vol. XVIII, pp. 16-29, 119-128.

Campbell, J. L. and H. D. William B, Rogers’ Geology of the Virginias.
A Review. Amer. Jour. Science (3), 1885, Vol. XXX, pp. 357-374;
1886; Vol. XXXI, pp. 193-202.

Campbell, M. R. Paleozoic Overlaps in Montgomery and Pulaski Counties,
Virginia. Bulletin Geological Society America, 1894, Vol. V, pp. 171-

190.

Geologic Atlas of the United States. Estillville Folio, No. 12, U. S.

Geological Survey, 1894,

Geologic Atlas of the United States. Pocahontas Folio, No. 26,

U. S. Geological Survey, 1896.

Geologic Atlas of the United States. Tazewell Folio, No. 44,

U. S. Geological Survey, 1897.

BIBLIOGRAPHY

377

Geologic Atlas of the United States. Bristol Folio, No, 59, U. S.

Geological Survey, 1899.

Darton, N. H. Notes on the Stratigraphy of a Portion of Central Appala-
chian Virginia. American Geologist, 1892, VoL X, pp. 10-18.

Geologic Atlas of the United States. Monterey Folio, No. 61, U. S.

Geological Survey, 1894.

Geologic Atlas of the United States. Staunton Folio, No, 14, U. S.

Geological Survey, 1894.

Geologic Atlas of the United States, Franklin Folio, No. 32, U. S.

Geological Survey, 1896.

Eckel, E. C. Cement Resources of the Cumberland Gap District, Tenn.-Va.
Bulletin No. 285, U. S. Geological Survey, 1904, pp. 374-376.

Cement Materials and Industry of the United States. Bulletin No.

243, U. S. Geological Survey, 1905.

Eckel, E, C. Cements, Limes and Plasters. Wiley and Sons, New York,
1905, 712 pages.

Ellett and Eskridge. Virginia Marls. Bulletin, Virginia Agricultural Ex-
periment Station, 1897, Vol. VI, pp. 65-70.

Keith, A. Geologic Atlas of the United States. Harpers Ferry Folio, No.
10, U. S. Geological Survey, 1894.

Kindle, E. M. Onondaga Fauna of the Allegheny Region, U. S. Geological
Survey, Bulletin No. 508.

Lesley, J, P. The Geological Structure of Tazewell, Russell and Wise Coun-
ties, Virginia. Proc. Amer. Philos. Society, 1873, XII, pp. 489-513.
McCreath, A. S. and dTnvilliers, E. V, The New River-Cripple Creek
Mineral Region of Virginia. Harrisburg, Pa., 1887, pp. 18, 24, 40, 51,
54-58, 70-75, 82, 89.

Morse, W. C. The Maxville Limestone. Ohio Geological Survey, Bulletin
No. 13, Fourth Series.

Rogers, W. B. Reports of Progress of the Geological Survey of the
State of Virginia (1836-1841).

A Reprint of the Geology of the Virginias. 1884, p. 832.

Spencer, Arthur Coe. The Geology of Massanutten Mountain in Virginia.
Washington, D. C., 1897.

Stevenson, John J. Notes on the Geology of Wise, Lee, and Scott Counties,
Virginia. Proc. Amer. Philos. Society, 1880, Vol. XIX, pp. 88-107.
Stevenson, John J. A Geological Reconnaissance of Parts of Lee, Wise,
Scott, and Washington Counties, Virginia. Proc. Amer. Philos. So-
ciety, 1881, Vol. XIX, pp. 219-262.

Notes on the Geological Structure of Tazewell, Russell, Wise,

Smyth, and Washington Counties of Virginia. Proc. Amer. Philos.
Society, 1885, Vol. XXII, pp. 114-116.

A Geological Reconnaissance of Bland, Giles, Wythe, and Portions

of Pulaski and Montgomery Counties, Virginia. Proc. Amer. Philos.
Society, 1887, Vol. XXIV, pp. 61-108.

Stose, G. W. Sedimentary Rocks of South Mountain. Jour. Geology, 1906,
Vol. XIV, pp. 201-220.

The Cambro-Ordovician Limestone of the Appalachian Valley in

Southern Pennsylvania. Jour. Geology, 1908, Vol. XVI, pp. 698-714.
and Miser, H. D. Manganese Deposits of Western Virginia. Vir-
ginia Geological Survey, Bulletin No. 23, 1922, pp. 5-55, 119-142.
Ulrich, E. O. and Schuchert, Charles. Paleozoic Seas and Barriers in East-
ern North America, New York State Museum Report, Bulletin No.
52, pp. 633-664.

Watson, Thomas L. Lead and Zinc Deposits of Virginia. Virginia Geologi-
cal Survey, Bulletin No. 1, Geological Series, 1905, pp. 156.

Watson, Thomas L. Lead and Zinc Deposits of the Virginia-Tennessee
Region. Trans. Amer. Inst. Mng. Engineers, 1906, Vol. XXXVI, pp.
681-737.

Mineral Resources of Virginia. Virginia Jamestown Exposition

Commission, 1907, pp. 618.

PLATE XLIII

Note on sources of Geologic Map of Giles Co.

This map was compiled from (1) Watson’s State Geologic Map of Vir-
ginia, (2) a map issued with Stose & Miser’s “Manganese Deposits,” (3) an
old map by J. J. Stevenson, published in Transactions of Amer. Philosophical
Society and (4) the work of the Class of 1922.

The manuscript maps by other classes were not used because this map
was completed before the accompanying manuscript had taken its present
form. The additional data on other MSS. maps would not make much
difference in a map on this scale and refinement but in a larger scale map
with formational units several areas of Romney, Giles, and Rockwood must
be changed. The authors.

Journal Scientific Laboratories Denison University Vol. XX

MlSSlSSlPPfAN.PRicc
sa., PU I.AS K j a H AWE,
aReenBRiEa ls.. bi.wE“
field SM-. AMO HiMtOM
3S

UPPER ArfO M(0-
Dce oevofiiMn

RonNEY AN® «IM'
BERLirt03H. A NO
TMIH $«MO«TONia

©!l_ES FORfMH-
TIOM. pRISKAri
SAN 03, HE L DEC
BERS AMD CA
USA IH PART.

UPPER OR0OVIC-
lAM- LOWER 51-
LURlftN.SEVIER
8AYS,CL1NCH,AMD
ROCKWOOO SANDS.

ORDOVICIAN UlME
CHICKAMAUeA
AND MOCCASIN
FORMATIONS.

HUBBARD AND CRONEIS

:OUNTY, VIRGINIA

1

.'V '.^ ;

^1^

A

1"^

Cu ^

-

-v. *

i

'■ .A'"'

1

, - 1

1

1

, '‘1

Journal Scientific Laboratories Denison University Vol. XX

PLATE XU

AND CRONEIS

HUBBARD

GEOLOC.Y op GILES COUNTY, VIRGINIA

SUBJECT AND AUTHOR INDEX

VOLUME XX

“A Botanical Survey of the Campus of Denison University,” By

Dwight Munson Moore 131

Amphicyrtoceras 255

Amphicyrtoceras laterale 257

orcas 255

tantalum ^ 259

“A Report on the Theory of Relativity. (Einstein Theory).” By Paul

Biefeld 269

“A Review of the Biology of Sex-Determination.” By Sidney I. Korn-

hauser ^ 1

Ascoceras 216

Bays Sandstone, Giles County, Va * 343

Bellerophon centervillensis 78

Beloitoceras 244

Beloitoceras lycum 251

pandion 245

plebeium 247

Biefeld, Paul. “A Report on the Theory of Relativity. (Einstein

Theory)” 269

“The Occultation of Venus by the Moon on January 13, 1923” 127

Billingsites 217

Billingsites (?) williamsportensis 217

Bluefield Shale, Giles County, Va 357

Brachyprion sp 75

Bfassfield Limestone of Ohio, Brachiopoda of 88

Buthotrephis 68

Buthotrephis creditensis 70

Calymene Ill

Calymene altirostris 110

cf. cedarvillensis 108

Cameroceras 212

Cameroceras calumettense 215

trentonense 213

Capillary action 161

Charactoceras 234

Charactoceras baeri 235

Chester Formation of Illinois, A Stigmarian Root from the 116

379

380

INDEX

Chickamauga Formation, Giles County, Va 330

Chromosomes and Sex 2

Clarkoceras 204

Clinch Sandstone, Giles County, Va 346

Correlation of Ohio, Indiana, and Kentucky Medinan and Niagaran

Strata 37

Croneis, Carey G. with Hubbard, George D. “Notes on the Geology of

Giles County, Virginia” 307

Cryptaulus 94

Cryptaulus filitextus 95

Ctenodonta 55

Ctenodonta (?) cataractensis 56

cf. simulatrix 87

(?) creditensis 55

Cycloceras : 222

Cyclonema daytonense 99

gyronemoides 101

Cyclostomiceras 205

Cyphaspis arkansana 114

spinulocervix 113

Cypricardinia jepthaensis 107

Cyrtogorhphoceras , 267

Dalmanella eugeniensis 52

Dalmanites sp 88

Dawsonoceras , 225

Diaphorostoma clintonense ; 103

daytonense 103

Dictyonema scalariforme creditensis 71

Dictyophlois reticulata illinoisensis 118

Diestoceras 262

Diestoceras eos 265

indianense 263

shideleri 266

Einstein Theory 269

Ellesmereoceras 202

Elrodoceras 228

Elrodoceras indianense 228

Endoceras 208

Endoceras proteiforme 210

Eremoceras 2U5

Eschman, Karl H. “Primitive Musical Instruments of the Denison

Collection” 28

Exogastric Cyrtoceroids of Canadian Age 206

Foerste, Aug. F. “Notes on American Paleozoic Cephalopods” 193

“Notes on Medinan, Niagaran, and Chester Fossils” 37

Geisonoceras 221

General Theory of Relativity. (Theory of Gravitation) 276

Giles Formation, Giles County, Va 352

INDEX

381

Gravitation 175

Gravitation, Theory of 276

Greenbrier Limestone, Giles County, Va 355

Guelph Formation of Ohio, Straparollus paveyi 115

Gynandromorphs and Mosaics 18

Hermaphroditism 19

Hinton Formation, Giles County, Va 357

Holochoanitic Cephalopods of Canadian Strata 197

Hormotoma centervillensis 81

trilineata 79

Hubbard, George D. and Croneis, Carey G. “Notes on the Geology of

Giles County, Va.” 307

Indefinite Percussion 29

Iron Resources of Giles County, Va 368

Kimberling Shale, Giles County, Va 354

Kornhauser, Sidney I. “A Review of the Biology of Sex-Determina-
tion” ; 1

Leptaena centervillensis 89

Leveilleites 60

Light Deflections Observed at the 1919 and 1922 Eclipses 285

Lindsey, A. W. “Some Problems of Taxonomy” 289

“The Egg and Larva of Hesperia Juba Bdv.” 121

“Trichoptilus Pygmaeus Wlsm and The Neuration of the Family

Pterophoridae” 187

Lingula cf. cuneata 51

Liospira (?) depressum 82

(?) sp 56

Lophospira ehlersi 83

bucheri 107

(Ruedemannia?) centervillensis 84

(Ruedemannia?) inexpectans 96

Lower Medinan Fauna Below the Brassfield Limestone in Ohio 72

Loxoceras 226

Loxoceras husseyi 86

Lyellia cf. thebesensis 106

Maelonoceras 242

Maelonoceras praematurum 242

Manganese Resources of Giles County, Va 361

Manitoulin Limestone at Credit Forks, Ontario, Fossils from the Base of 58
Mathematical and Experimental Tests of the General Theory of

Relativity 283

Mather, Kirtley F. “The Meander Patterns of Rios Secure and

Mamore, Eastern Bolivia” 22

“The Underground Migration of Oil and Gas” 155

Moccasin Limestone, Giles County, Va 336

Modiolopsis orthonota creditensis 53

Monocyrtoceras lentidilatatum 260

382

INDEX

Moore, Dwight Munson. “A Botanical Survey of the Campus of

Denison University’’ 131

Multipipes — Organ Type 34

Neuration of the Family Pterophoridae 187

Niagarian Fossils from Jeptha Knob, Kentucky 105

“Notes on American Paleozoic Cephalopods.” By Aug. F. Foerste........ 193

“Notes on Medinan, Niagaran, and Chester Fossils.” By .Aug. F.

Foerste 37

“Notes on the Geology of Giles County, Virginia.” By George D. Hub-
bard and Carey G. Croneis 307

Occultations, Theory of 128

Oncoceras 239

Oncoceras constrictum : 240

Onychochilus abruptum 104

Orthis bucheri 109

dinorthis 91

euorthis 91

fissiplicata 92

Orthoceras 218

Orthoceras clarksvillense ! 220

Orygoceras 203

Oxydiscus youngi 94

Parastrophia sparsiplicata 93

Perigrammoceras 224

Platymerella manniensis 92

Polyembryony 10

Poterioceras 254

Price Sandstone, Giles County, Va 355

“Primitive Musical Instruments of the Denison Collection.” By Karl

H. Eschman 28

Protocycloceras .- 202

Proetus vaningeni 112

Pterophoridae, Key to the North American Genera of 192

Pulaski Shale, Giles County, Va 355

Restricted Principle of Relativity 269

Rhynchotreta thebesensis 77

Rockwood Formation, Giles County, Va 347

Romney Shale, Giles County, Va 353

Russell Formation, Giles County, Va. 318

Sactoceras 227

St. Clair Limestone of Arkansas, Trilobites from 109

Schuchertella creditensis 52

daytonensis 91

subplana brevior 75

Secondary Sexual Characteristics and Hormones 14

Sediments, Cementation of 160

Compacting of 157

Induration of 156

INDEX

383

Sevier Shales^ Giles County, Va 339

Sex-Linked Inheritance 11

Shenandoah Limestone, Giles County, Va 321

Smooth Orthoconic Canadian Caphalopods 200

“Some Problems of Taxonomy/’ By A. W. Lindsey 289

Species Concept 290

Specific Gravity, Differences in : 176

Spyroceras 225

Spyroceras microtextile 87

Stabilization of Genera 300

Straparollus (?) pervetustus 57

Stringed Instruments with Bow 33

Fingerboards 32

Strophonella daytonensis 91

hanoverensis 90

milleri 106

Subspecific Divisions 293

Tertiary Gravels, Giles County, Va 357

“The Egg and Larva of Hesperia Juba Bdv.” By A. W. Lindsey 121

“The Meander Patterns of Rios Secure and Mamore, Eastern Bolivia.”

By Kirtley F. Mather 22

“The Occultation of Venus by the Moon on January 13, 1923.” By P.

Biefeld 127

“The Underground Migration of Oil and Gas.” By Kirtley F. Mather 155
“Trichoptilus Pygmaeus Wlsm and The Neuration of the Family

Pterophoridae.” By A. W. Lindsey 187

Tripteroceras 231

Tripteroceras hastatum 232

pauquettense 233

Underground Water, Movements of; nature of the movement 178

Westenoceras 253

Whirlpool Sandstone of Ontario, The Fauna of 50

Whitfieldella cf. cataractensis 92

cf. ovoides 76

circularis 53

VOLUME 16

Articles 1-3, pp. 1-120; June, 1910 $1.10

The metamorphism of glacial deposits ; F. Carney. 14 pp., 7 figs.

Preliminary notes on Cincinnatian and Lexington fossils of Ohio, Indiana, Kentucky, and
Tennessee; Aug. F. Foerste. 81 pp., 5 figs., 7 plates.

The abandoned shorelines of the Oberlin Quadrangle, Ohio ; Frank Carney. 16 pp., 5 figs.

Articles 4-7, pp. 119-232; Dec., 1910 $0.75

Standardisation of well water in the vicinity of Granville, Ohio; Lily Bell Sefton. 5 pp.

Chapters on the geography of Ohio; F. Carney.

Transportation; 11 pp.

Economic mineral products ; 47 pp.

Glaciation in Ohio ; 48 pp.

Articles 8-12, pp. 233-346; April, 1911 $0.75

The abandoned shorelines of the Vermilion Quadrangle, Ohio ; F. Carney. 12 pp., 2 figs.
Thermo-electric couples ; A. W. Davidson. 21 pp., 16 figs.

The Mercer limestone and its associated rocks in the Newark-Zanesville region ; Clara G. Mark.

47 pp., 2 plates, 5 figs.

A study of the supposed hybrid of the Black and Shingle oaks; Earl H. Foote, 18 pp., 4 plates.

A case of pre-glacial stream diversion near St. Louisville, Ohio ; Howard. Clark, 8 pp., 4 figs.

Articles 13-17, pp, 347-423 ; July, 1911 $0.65

The Swasey Observatory, Denison University ; Herbert G. Wilson. 5 pp., 4 figs.

The contribution of Astronomy to general culture ; Edwin B. Frost. 12 pp.

The geological development of Ohio; F. Carney. 15 pp.

The relief features of Ohio; F. Carney. 13 pp., 1 fig.

Geographic conditions in the early history of the Ohio country ; F. Carney. 20 pp.

VOLUME 17

Articles 1-4, pp. 1-20 ; March, 1912 $1.50

A geographic interpretation of Cincinnati, Ohio ; Edith M. Southall, 16 pp.

Strophomena and other fossils from Cincinnatian and Mohawkian horizons, chiefly in Ohio,
Indiana, Kentucky ; Aug. F. Foerste. 158 pp., 18 plates.

Population centers and density of population ; F. Carney. 15 pp.

The climate of Ohio ; F. Carney. 9 pp.

Articles 5-7, pp. 203-246; March, 1913 $0.40

The twenty-fifth anniversary of the founding of the Denison Scientific Association ; 2 pp.

The foundation of culture; C, Judson Herrick. 14 pp.

Drainage changess in the Moots Run area. Licking County, Ohio ; Harmon A. Nixon and Dexter J.

Tight. 11 pp., 1 fig.

Some pre-glacial lake shorelines of the Bellevue quadrangle, Ohio ; F. Carney. 16 pp., 3 figs.

Articles 8-10, pp. 247-373; March, 1914 $1.00

Lorraine faunas of New York and Quebec ; Aug. F. Foerste. 93 pp., 5 plates,

A comparative study of circular and rectangular Inhoff tanks; Theodore Sedgwick Johnson. 26 pp.
Geographic factors in the establishing of the Ohio-Michigan boundary line ; Constance Grace
Eirich. 7 pp.

Articles 11-14, pp. 375-487 ; September, 1914 $1.00

A method of subdividing the interior of a simply closed rectifiable curve with an application to
Cauchy’s theorem ; F. B, Wiley and G. A. Bliss. 14 pp., 3 figs.

The influence of glaciation on agriculture in Ohio ; Edgar W. Owen, 4 pp., 1 fig.

The Locust Grove Esker, Ohio; James D. Thompson, Jr., 4 pp., 1 fig.

Notes on Agelacrinidae and Lepadocystinae, with descriptions of Thresherodiscus and Brockocystis ;

Aug, F. Foerste. 88 pp., 6 plates.

VOLUME 18

Articles 1-3, pp. 1-284 ; December, 1915 $1,75

Proceedings of the inauguration of President Chamberlain ; 54 pp.

Denison University presidents; William Hannibal Johnson. 5 pp.

The fauna of the Morrow Group of Arkansas and Oklahoma ; Kirtley F. Mather. 226 pp., 2 figs.,

16 plates.

Articles 4-7, pp. 285-378 ; December, 1916 $1.10

Notes on Cincinnatian fossil types; Aug. F. Foerste. 71 pp., 7 plates.

The shorelines of glacial lakes Lundy, Wayne, and Arkona, of the Oberlin Quadrangle, Ohio;

Frank Carney. 6 pp., 1 fig.

The progress of Geology during the period 1891-1915; Frank Carney. 8 pp., 4 figs.

’The abandoned shorelines of the Ashtabula Quadrangle, Ohio; Frank Carney, 24 pp., 4 figs.

VOLUME 19

Articles 1-4, pp. 1-64 ; April, 1919 $0.75

Echinodermata of the Brassfield (Silurian) formation of Ohio ; Aug. F. Foerste. 30 pp., 7 plates.
America’s advance in potash production ; W. C. Ebaugh. 14 pp., 2 figs.

The use of outline charts in teaching vertebrate paleontology; Maurice G. Mehl. 8 pp., 1 fig.,

4 plates.

Some factors in the geographic distribution of petroleum ; Maurice G. Mehl. 0 pp„ 2 plates.

Articles 5-8, pp. 65-146 ; September, 1919 $0.75

Notes on Isotelus, Achrolichas, Calymene and Encrinurus ; Aug. F. Foerste. 18 pp., 6 plates.

Some suggested experiments for the graphic recording of speech vibrations ; Rpbert James Kel-
logg. 14 pp.; 6 figs.

The manipulation of the telescopic alidade in geologic mapping ; Kirtley F. Mather. 46' pp., 13 figs.

The importance of drainage area in estimating the possibilities of petroleum ' production from
an anticlinal structure; Kirtley F. Mather and Maurice G. Mehl. 4 pp., 2 plates.

Articles 9-12, pp. 147-224; May, 1920 $0.75

Psychological factors in vocational guidance; Thomas A. Lewis. 10 pp.

The \ise of models in the interpretation of data for determining the structure of bMded rocks ;
Maurice G. Mehl. 12 pp., 6 figs., 2 plates.

Some suggestions for indicating drilling operations ; Maurice G. Mehl. 6 pp., 3 figs.

The Kimmswick and Plattin limestones of Northeastern Missouri ; Aug. F. Foerste. 50 pp.,

3 plates.

Articles 13-16, pp. 225-329; September, 1921 : $0.75

Education for scholarship ; William E. Castle., * ’Q pp.

The cytology of the sea-side earwig, Anisolabis maritima Bon., part 1 ; Sidney I. Kornhauser.

13 pp., 3 plates.

Notes on Arctic Ordovician and Silurian cephalopods ; Aug. F. Foerste. 60 pp., 9 plates.

Revolution vs. evolution : the paleontologist renders his verdict ; Kirtley F. Mather. 18 pp.

VOLUME 20

Articles 1-3, pp. 1-36 ; November, 1922 $0.50

A review of the biology of sex-determination ; Sidney I. Kornhauser. 21 pp., 8 figs.

The Meander patterns of Rios Secure and Mamore, Eastern Bolivia; Kirtley F. Mather. 7 pp.,

2 figs.

Primitive musical instruments of the Denison Collection ; Karl K[. Eschman. 10 pp., 3 plates.

Articles 4-8, pp. 37-186; June, 1923 $0.75

Notes on Medinan, Niagaran, and Chester fossils ; Aug. F. Foerste. 84 pp., 13 plates.

The egg and larva of Hesperia juba Bdv. ; A. W. Lindsey. 7 pp., 1 plate.

The occultation of Venus by the Moon on January 13, 1923 ; P. Fiefeld. 4 pp., 1 plate.

A botanical survey of the campus of Denison University; Dwight Munson Moore. 23 pp., 7 figs.,

8 plates.

The underground migration of oil and gas ; Kirtley F. Mather. 31 pp., 1 fig.

NOTEzIn accordance with a ruling of the iM>stal autliorities it has becom€i
necessary to change the name of this publication from ^'BULLETIN” to ^'JOURNAL**
of the SCIENTIFIC LABORATORIES of DENISON UNIVERSITY.

)>»»»