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BOOK 56 1.B19 C.I

BALFOUR # INTRODUCTION TO STUDY

OF PALOEONTOLOGICAL BOTANY

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INTRODUCTION

TO THE STUDY OF

PAL^ONTOLOGICAL BOTANY

INTRODUCTION

TO THE STUDY OF

PALiEONTOLOGICAL BOTANY

BY

JOHN HUTTON BALFOUE, A.M. M.D. EDIN.

F.R.S., SEC. R.S.E., F.L.S.

PROFESSOR OF MEDICINE AND BOTANY IN THE UNIVERSITY OF EDINBURGH,

REGIUS KEEPER OF THE ROYAL BOTANIC GARDEN,

AND queen's botanist FOR SCOTLAND

WITH FOUR LITHOGRAPHIC PLATES, AND UPWARDS OF
ONE HUNDRED WOODCUTS

EDINBUEGH

ADAM AND CHAELES BLACK

1872

B\S

SfeS^.

Prhited by R. & R. Clark, Edinburgh.

TO

PROF. HEmRICH ROBERT GOEPPERT, M.D.,

DIRECTOR OF THE BOTAXIC GARDEN, ERESLAU ;

ONE OF THE MOST EMINENT PALiEONTOLOGICAL
BOTANISTS OF EUROPE,

Ei}t foUotoms treatise

IS DEDICATED, WITH BEST RESPECTS, BY HIS
OBLIGED FRIEND

THE AUTHOR.

PREFACE.

The subject of Fossil Botany or Palfeopliytology has formed
a part of the Course of Botany in the University of Edinburgh
for the last twenty-five years, and the amount of time devoted
to the exposition of it has increased. The recent foundation
of a Chair of Geology and of a Falconer Pal^eontological
Fellovrship in the University seems to require from the
Professors of Zoology and Botany special attention to
the bearings of their departments of science on the stmcture
of the animals and plants of former epochs of the Earth's
history. No one can be competent to give a correct decision
in regard to Fossils, unless he has studied thoroughly the
present Fauna and Flora of the globe. To give a well-
founded opinion in regard to extinct beings, it is essential
that the observer should be conversant with the conforma-
tion and development of the living ones now on the earth ;
with their habits, modes of existence and reproduction, the
microscopic structure of their tissues, their distribution, and
their relation to soil, the atmosphere, temperature, and
climate.

There can be no doubt that to become a good Fossil
Geologist a student must begin with living animals and
plants. The study of Geology must be shared by the

VIU PREFACE.

Petralogist, who looks at the condition of the rocks of
the globe, the minerals forming them, and their mode of
formation ; the Chemist, who determines the materials which
enter into the composition of minerals and rocks ; the
Naturalist, who examines the plants and animals found in
the various strata; and perhaps also the Natural Philoso-
pher, who calculates from independent sources the phases
of the Earth's histoiy. It may be said thus to combine all
these students of Science in one brotherhood. Much has
been done by the efforts of such men as Hutton and Werner,
who were engaged chiefly in considering the mineral de-
partment of Geology ; but it is clear that the Science could
not have attained its present position without the continued
labours of those who have been examining fossils in their
relations to time and space. Had it not been for the re-
searches of Palaeontologists, Geology could not have made
its present advance.

In my Class Book of Botany I have given an introduction
to Pala3ophytology, and it occurred to me that it might be
useful to students to publish this in a separate form, with
additions in both the letterpress and the illustrations. The
institution of the Pala3outological Fellowship, in memory
of my former friend Dr. Falconer, has brought the subject
specially under my notice. The Fellowship has been pro-
moted chiefly by my friend and former pupil Dr. Charles
Murchison, a gentleman fond of science and of his Alma
Mater, the University of Edinburgh, where he and Falconer
studied and took their degrees.

The first award of the Fellowship has been made to a
distinguished student, who acquitted himself with the greatest
credit during the three days of examination on Geology,

PREFACE. IX

Zoology, and Botany. I trust that the Fellowship will
continue to stimulate our eminent students in future years.

Having been a student of Natural Science along with
Dr. Falconer, I feel a peculiar interest in doing what I can
to promote the study of a subject to which he so successfully
devoted his energies. In my endeavour to do so I have
been encouraged by my friend and fonner pupil, Mr. William
Carruthers, at the head of the Botanical Department of the
British Museum, and a former student in Edinburgh under
the late Professor Fleming. He has done much to advance
our knowledge of Fossil Botany, and to him I am indebted
for two of the plates and some of the woodcuts which illus-
trate this publication. He has given me most efficient
assistance, and I have to return my best thanks for his
kind aid. I am also indebted to my colleague, Professor
Geikie, for his valued assistance.

The neighbourhood of Edinburgh is rich in Fossils of
the Carboniferous epoch, and much yet remains to be done
to illustrate its Palaeontology. Such labourers as Geikie
and Peach may be expected to give great assistance in the
furtherance of our knowledge of Scottish Geology, so as to
form a school which shall revive the reputation enjoyed by
Edinburgh in the days of Hutton and Jameson. If I can
be useful in encouraging students to take up the study of
Palteontological Botany, and to prosecute it with vigour, I
shall feel that this introductory treatise has not been issued
in vain. As one of the few surviving relations of Dr. James
Hutton, I am glad to be able to show an interest in a science
which may aid in elucidating the " Theory of the Earth."

In writing this work I have taken for granted that the
reader is acquainted with the Elements of Botany, and knows

X PREFACE.

the general structure of plants of the present day. I have
not, therefore, hesitated to use the ordinary Botanical terms
without explanation. I am satisfied that no one can study
Fossil Botany properly unless he has studied Modern Botany.
Those readers who may find any difficulty as to technical
terms I would refer to my Botanist's Companion, where a
full Glossary is given.

27 Inveeleith Row,

May 1872.

TABLE OF CONTENTS.

PACE

Introductory Remarks . . . . .1

Determination of Fossil Plants .... 3

Mode of Preservation of Fossil Plants . . .8

Examination of the Structure of Fossil Plants . 12

FOSSILIFEROUS RocKS . . . • .20

Natural Orders to which Fossil Plants belong . 22

Periods of Vegetation among Fossil Plants . . 25

Fossil Flora of the Primary or Paleozoic Period . 26

Reign of Acrogens . . . . . 26

Flora of the Carboniferous Epoch . . .36

Flora of the Permian Epoch . . . .71

Fossil Flora of the Secondary or Mesozoic Period . 72

Reign of Gymnosperms . . . . .72

Flora of the Trias and Lias Epochs . . .77

Flora of the Oolitic Epoch . . . .80

Flora of the Wealden Epoch . . . . 84

Fossil Flora of the Tertiary or Cainozoic Period (includ-
ing the Cretaceous Epoch) . . . .87

Reign of Angiosperms . . . . .87

Flora of the Chalk . . . . .87

xu

TABLE OF CONTENTS.

PAGE

Flora of the Eocene Epoch

. 90

Flora of the Miocene Epoch

. 92

Flora of the Pliocene Epoch

. 98

General Conclusions

. 101

Recapitulation ....

. 103

Works on Fossil Botany .

. 105

Explanation of Plates

. Ill

Index .....

. 113

LIST OF WOODCUTS.

Fig.
1.

2.
3.

4.
5.
6.

7.

Section of Peuce Withami, Lindley and Hutton
Bark of Araucaria .....
Llarkings on Araucaria bark

Leaf of Araucaria

Nicolia Owenii (Carr.)

Bryson's instrument for slitting Fossils

Tree-fern ....

Asplenium ....

1 1 a. Bifurcating Trunk of a Tree-fern (Alsophila Perrottetiana)
1 1 &. Rhizome of Lastrea Filix-mas
1 2. Transverse section of stem of a Tree-fern (Cyatliea)

Scalariform vessels from Tree-fern

Sporangia of a Fern .....

Lycopodium clavatum . . . ' .

Spore-case, containing Microspores of Lycopodium
„ ,, Macrospores of Selaginella

Fructification of Equisetum maximum

Polygonal scale of Equisetum

Spore of Equisetum — filaments contracted
„ „ J, expanded

Marsilea Fabri ....
22 bis. Adiantites Lindseteformis .
23. Pecopteris (Alethopteris) aquilina

,, (Alethopteris) heterophylla

Neuropteris Loshii

„ gigantea .

„ acuminata

Sphenopteris affinis

Cyclopteris dilatata

9.
10.

13.
U.
15.
16.
17.
18.
19.
20.
21.
22.

24.
25.
26.

27.
28.
29.

Page

3
5

6

6

7

7

11

14

27

28

29

29

29

30

30

30

30

30

31

32

32

32

33

41

43

43

43

43

43

43

43

XIV

LIST OF WOODCUTS.

Fig.

30. Stem of Caulopteris macrodisciis .

31. „ ,, Balfonri (Carr.)

32. „ ,, Morrisi (Carr.)

33. ,, Sigillaria pachy derma

34. Sigillaria reuiformis

35. ,, pachyderma

36. ,, (Faviilaria) tessellata

37. „ pachyderma

38. Stigmaria ficoides

39. ,, „ (S, anabathra of Corda)

40. Bifurcating stem of Lepidodendron obovatum (elegans)

41. Stem of LeiDidodendron crenatum

42. Fructification of Lepidodendron

43. Longitudinal section of Fructification of Triplosporites

44. (1). Fruit of Selaginella spinulosa, A. Braun (Lycopodium

selaginoides, Linn.) .....

(2). Scale and sporangium from the upper part of cone

(3). Antheridian microspores from ditto

(4). Macrospore ......

(5). Scale and sporangium from lower part of cone, con
taining macrospores ....

(6). Fruit of Lepidostrobus ornatus (Hooker)

(7). Three scales and sporangia of ditto

(8). Microspores from sporangia of the upper part of the

cone of Triplosporites Brownii, Brongn.
(9). Macrospore from the sporangia of the lower part
(10). Scales and sporangia of a cone of Flemingites
45 a. Calamites Suckovii
45 6. Septum or Phragma of a Calamite

46. Vertical stems of Calamites — in coal-measures of Treuil

near St. Etienne

47. Fruits of Equisetum and Calamites
(1). Equisetum arvense, L.
(2). Portion of sporangium wall .
(3, 4). Spores — elaters free

(5). Longitudinal section of part of one side of cone
(6). Transverse section of cone
(7). Calamites (Volkmannia) Binneyi (Carr.)
(8). Portion of sporangium wall .
(9). Two spores ....

Page

44
44
44
45
45
46
46
46
47
47
49
49
50
50

51
51
51
51

51
51

51

51
51
51
57

57

68
60
60
60
60
60
60
60
60
60

LIST OF WOODCUTS.

XV

Fig. Page

(10). Longitudinal section of part of one side of cone . 60
(11). Transverse section of cone . . . . .60

48. Foliage and fruits of Calamites . . . . .62

(1, 2). Asterophyllites 62

(3, 4). Annularia 62

(o, 6). Sphenophyllum . . . . . .62

49. Araucarioxylon Witliami, Krauss (Pinites Withami) . 63

50. Trigonocarpum olivseforme . . . . . .63

51. Cardiocarpum Lindleyi (Carr.) . . . . .65

52. „ „ 65

53. Cardiocarpum anomalum (Carr.) . . . . .66

54. Pothocites Grantoni (Paterson) . . . . .67

55. 56. Walcliia piniformis (Sternb.) . . . . .72

57. Pinus sylvestris . . . . . . .73

58. Abies excelsa ........ 73

59. Larix Europsea ........ 73

60. Cedrus Libaui . . . . . . . .73

61. Araucaria excelsa . . . . . . .74

62. Woody tubes of fir — single rows of discs . . .74

63. „ ,, — double and opposite rows of discs . 74

64. Woody tubes of Araucaria excelsa — double and triple

and alternate rows of discs ..... 74

65. Longitudinal section of stem of a Gymnosperm . . 74

66. Linear leaves of Pinus Strobus . . . , -75

67. Cone of Pinus sylvestris ...... 75

68. „ Cupressus sempervirens ..... 75

69. Scale of mature cone of Pinus sylvestris ... 75

70. Fruiting branch of Jimiperus communis . . .76

71. Branch of Taxus baccata . . . . . .76

72. Male flower of Yew 76

73. Fruit of Yew 76

74. Cycas revoluta . . . "^ . . . . .77

75. Encephalartos (Zamia) pungens ..... 77

76. Schizoneura heterophylla ...... 78

77. Zamites 79

78. Pterophyllum Pleiningerii ...... 80

79. ISTilssonia compta (Pterophyllum comptum of Lindley

and Hutton) 80

80. Palteozamia pectinata (Zamia pectinata of Brongniart, and

Lindley and Hutton) ...... 80

XVI

LIST OF WOODCUTS.

Fig. Page

81. Brachyphyllum mammillare . . . . .81

82. Equisetum columnare . . . . . .81

83. Araucarites sphserocarpus (Carr.) . ... 82

84. Termination of a scale of ditto ..... 82

85. Section of a scale of ditto ...... 82

86. The Dirt-bed of the island of Portland .... 83

87. Cycadoidea megalophylla (Mantellia nidiformis of Brong-

niart) ......... 83

88. Kaidacarpum ooliticum (Carr.) 84

89. Pandanus odoratissimus ...... 84

90. Fossil wood, Abietites Linkii 85

91. Sequoiites ovalis ....... 88

92. Pinites ovatus (Zamia ovata of Lindley and Hutton) . 89

93. Palmacites Lamanonis ...... 90

94. Osmunda regalis . . . . . . .91

95. Comptonia acutiloba . . . . . . .92

96. Acer trilobatum ....... 93

97. Ulmus Bronnii . . . . . . .93

98. Rhamnus Aizoon ....... 94

99. Alniis gracilis ........ 95

100. Taxites or Taxodites Campbellii ..... 95

101. Rhamnites multinervatus ...... 95

102. Equisetum Campbellii ...... 96

PAL^ONTOLOGICAL BOTANY.

The study of the changes which have taken place in the
nature of living beings since their first appearance on the
globe till the period when the surface of the earth, having
assumed its present form, has been covered by the creation
which now occupies it, constitutes one of the most important
departments in Geology. It is, as Brongniart remarks, the
history of life and its metamorphoses. The researches of
geologists show clearly that the globe has undergone various
alterations since that "beginning" when "God created the
heavens and the earth." These alterations are exhibited in
the different stratified rocks which fomi the outer crust
of the earth, and which were chiefly sedimentary deposits
produced by the weathering of the exposed rocks. Re-
mains of the plants and animals living on the globe at
the time of the formation of the different beds are pre-
served in them. Elevations and depressions of the sur-
face of the earth affected the organisms on its surface, and
gave to successive deposits new faunas and floras. Some of
these epochs have been marked by great changes in the
physical state of our planet, and they have been accompanied
with equally great modifications in the nature of the living
beings which inhabited it. The study of the fossil remains of
animals is called Palseozoology (jTaXaio^, ancient, and ^SoVj
animal), while the consideration of those of vegetables is
denominated Pal^eophytology (TraXatos and (jyvrov, a plant).
Both are departments of the science of Palaeontology, which

B

2 PAL^ONTOLOGICAL BOTANY.

has been the means of bringing geology to its present state of
advancement. The study of these extinct fonns has afforded
valuable indications as to the physical state of the earth, and
as to its climate at different epochs. This study requires
the conjunct labours of the Zoologist, the Botanist, and the
Petralogist.

The vegetation of the globe, during the different stages of
its formation, has undergone very evident changes. At the
same time there is no reason to doubt that the plants
may all be referred to the great classes distinguished at
the present day — namely, Thallogens, including such plants
as Lichens, Alga3, and Fungi ; Acrogens, such as Ferns and
Lycopods; Gymnosperms, such as Cone-bearing plants and
Cycads ; Endogens, such as Palms, Lilies, and Grasses ; and
Exogens, such as the common trees of Britain (excluding the
Fir), and the great mass of ordinary flowering plants. The
relative proportion of these classes, however, has been different,
and the predominance of certain forms has given a character
to the vegetation of different epochs. The farther we recede
in geological history from the present day, the greater is the
difference between the fossil plants and those which now
occupy the surface. At the time when the coal-beds were
formed, the plants covering the earth belonged to genera
and species not existing at the present day. As we ascend
higher, the similarity between the ancient and the modern
flora increases, and in the latest stratified rocks we have in
certain instances an identity in sj^ecies and a considerable
number of existing genera. At early epochs the flora appears
to have been uniform, to have presented less diversity of
forms than at present, and to have been similar in the dif-
ferent quarters of the globe. The vegetation also indicates
that the nature of the climate was different from that which
characterises the countries in which these early fossil plants
are now found.

DETERMINATIOX OF FOSSIL PLANTS.

Determination of Fossil Plants.

Fossil plants are by no means so easily examined as recent
species. They are seldom found in a complete state. Frag-
ments of stems, leaves, and fruits, are the data by which the
plant is to be determined. It is very rare to find any traces
of the flowers. The parts of fossil
plants are usually separated from each
other, and it is difficult to ascertain
what are the portions which should be
associated together so as to complete an
individual plant. Specimens are some-
times preserved, so that the anatomical
structure of the organs, especially of
the stem, can be detected by very
thin slices placed under the micro-
scope. In the case of some stems the
presence of punctated woody tissue
(Fig. 1) lias proved of great service as
regards fossil Botany ; this structure, Fig. i.

along with the absence of large pitted ducts, serving to
distinguish Conifers. The presence of scalariform vessels
indicates a plant belonging to the vascular Crj^ptogams, of
which the fern is the best known example. The cautions
to be observed in determining fossil plants are noticed by
Dr. Hooker in the JNIemoirs of the Geological Survey of
Great Britain (vol. ii. p. 387). At the present day, the
same fern may have different forms of fronds, which, un-
less they were found united, might be reckoned distinct
genera; and remarkable examples are seen in Niphobolus
rupestris and Lindsa3a cordata. Moreover, we find the same
form of frond belonging to several different genera, which can

Fig. 1. Section of Peuce JVithajni, after Lindley and Hutton, a
fossil Conifer of the coal epoch. Punctated woody tissue seen.

4 PAL.S:ONTOLOGICAL BOTANY.

only be distinguished by the fructification; and as this is rarely
seen in fossil ferns, it is often impossible to come to a decided
conclusion in regard to them. A leaf of Stangeria paradoxa
was considered by an eminent botanist as a barren fern frond,
but it ultimately proved to be the leaf of a Cycad. The leaf
of Cupania filicifolia, a Dicotyledon, might easily be mistaken
for that of a fern ; it resembles much the frond of a fossil fern
called Coniopteris. The diverse leaves of Sterculia diversi-
folia, if seen separately, might easily be referred to different
plants. In the same fern we meet also with different kinds of
venation in the fronds. Similar remarks may be made in
regard to other plants. Harvey has pointed out many diffi-
culties in regard to sea-weeds.

As regards the materials for a fossil flora, the following
remarks of Hugh Miller deserve attention : —

*^ The authors of Fossil Floras, however able or accom-
plished they may be, have often to found their genera and
species, and to frame their restorations, when they attempt
these, on very inadequate specimens. For, were they to pause
in their labours until better ones turned up, they would find
the longest life greatly too short for the completion of even a
small portion of their task. Much of their work must be of
necessity of a provisional character — so much so, that there
are few possessors of good collections who do not find them-
selves in circumstances to furnish both addenda and errata to
our most valuable works on Palasontology. And it is only by
the free communication of these addenda and errata that
geologists will be at length enabled adequately to conceive of
the by-past creations, and of that gorgeous Flora of the Car-
boniferous age, which seems to have been by far the most
luxuriant and wonderful which our emphatically ancient earth
ever saw."

The bark of trees at the present day often exhibits
different kinds of markings in its layers. This may be illus-

DETERMINATION OF FOSSIL PLANTS. 5

trated by a specimen of Araucaria imbricata, which was
destroyed by frost in the Edinburgh Botanic Garden on 24th
December 1861. The tree was 24 J feet high, with a circum-
ference of four feet at the base of the stem, and had twenty
whorls of branches. The external surface of the bark is
represented in Fig. 2. There are seen scars formed in part by

Fig. 2.

prolongations from the lower part of the leaves, which have
been cut off close to their union with the stem. The base of
each leaf remaining in the bark has the form of a narrow
elongated ellipse, surrounded by cortical foliar prolonga-
tions. The markings on the bark, when viewed externally,
have a somewhat oblique quadrilateral form. On removing
the epiphloium or outer bark, and examining its inner
surface, we remark a difference in the appearance presented
at the lower and upper part of the stem. In the lower
portion the markings have an irregular elliptical form, with
a deep depression, and fissures where the leaves are attached
(Fig. 3). Higher up the epiphloeal markings assume rather
more of a quadrilateral form, with the depressions less deep,
and the fissures for the leaves giving off prolongations on
Fig. 2. Bark of Araucaria imhricata.

6 PAL^ONTOLOGICAL BOTANY.

either side. Farther up the markings are smaller in size,

FiR. 3.

obliquely quadrilateral, and present circular dots along the
boundary lines chiefly (Fig. 4). Higher still the quadrilateral

Fig. 4.

form becomes more apparent, and the dots disappear (Fig. 5).
The epiphloeum thus presents differences in its markings
at different heights on the stem.

The part of the bark immediately below the epiphlceum is
well developed, and is of a spongy consistence. When
examined microscopically it is seen to be composed of cells of
Figs. 3, 4, and 5. Markings on Araucaria bark.

DETERMINATION OF FOSSIL PLANTS.

various shapes — some elongated fusiform, others rhomboidal,
others with pointed appendages. The variety of forms is very

Fig. 5.

great, but it is possible that this may be partly owing to the
effects of frost on the cells. On the spontaneous separation
of the bark, the portion below the epiphlocum was seen to
consist of distinct plates of a more or less quadrilateral form,
with some of the edges concave and others convex, a part in
the centre indicating the connection with
the leaf, along with which it is detached.
In Fig. 6 a leaf is shown with one of these
plates attached.

The appearances presented by the outer
and middle bark of Araucaria imbricata bear
a marked resemblance to those exhibited by
certain fossils included in the genera Sigil-
laria and Lepidodendron. The sculpturesque
markings on the stems of these fossil plants
indicate their alliance to the ferns and
lycopods of the present epoch. But it
is evident, frmn these markings, that much
caution is required in making this deter-
mination. Other points of structure must
be examined before a proper decision can be formed. When,
Fig. 6. Leaf of Araucaria with a portion of bark.

Fi£c. 6.

8 PALiEONTOLOGICAL BOTANY.

for instance, the presence of scalariform tissue, or of
punctated woody tissue, lias been satisfactorily shown under
the microscope, we are entitled to hazard an opinion as
to the affinities of the fossils. In many instances, how-
ever, external appearances are the only data on which to
rely for the determination of fossil genera and species ; and
rash conclusions have often been drawn by geologists who
have not been conversant with the structure of plants. The
Araucaria markings point out the need of care in drawing
conclusions, and their variations at different parts of the bark
indicate the danger of a rash decision as to species. There
can be no doubt that in vegetable Pala3ontology the number
of species has been needlessly multiplied — any slight variation
in form having been reckoned sufficient for specific distinction.
We can conceive that the Araucaria bark markings in a fossil
state might easily supply several species of Lepidodendron.
A naturalist, with little knowledge of the present flora of the
globe, ventures sometimes to decide on an isolated fragment.
Hence the crude descriptions of fossil vegetable forms, and the
confusion in which Pala3ophytology is involved. Every geo-
logist who examines fossil plants ought to be well acquainted
with the minute structure of living plants, the forms of their
roots, stems, leaves, fronds, and fructification ; the markings
on the outer and inner surfaces of their barks, on their stems,
and on their rhizomes ; the localities in which they grow, and
the climates which genera and species affect in various parts
of the world. (Professor Balfour in the Proceedings of the
Royal Society of Edinburgh, April 1862, vol. iv. p. ^77*)

Mode of Preservation of Fossil Plants.

The mode in which plants are preserved in a fossil state may
be referred to four principal classes : — 1. Casts of the plants ;
from which all the original substance and structure have been
removed subsequently to the burial of the plants, and to the

MODE OF PRESERVATION OF FOSSIL PLANTS. 9

greater or less induration of the rocks in which they are en-
tombed. Such casts are occasionally hollow, but more
frequently they consist of the amorphous substance of the
rock which has filled up the cavity, and which exhibits,
often with remarkable minuteness, the external aspects of
the original specimen. 2. Carbonisation ; in which the
original substance of the plant has been chemically altered
and converted into lignite or coal. All trace of the form of
the original plant is generally lost, as is the case with the
extensive beds of coal; but frequently, when the organism
has been buried in a bed of clay, the external appearance is
faithfully preserved, as in the ferns and other foliage found
in the shales of the coal-measures. 3. Infiltration ; in which
the vegetable tissues, though carbonised, retain their original
form from the infiltration of some mineral in solution, chiefly
lime or silex, which has filled the empty cells and vessels,
and so preserved their original form. This mode of pre-
servation occurs in the calcareous nodules in coal-beds, in the
remarkable ash-beds discovered by Mr. WUnsch in Arran, and
generally in the secondary rocks. 4. Petrifaction ; in w^hicli
the structure is preserved, but the whole of the original
substance has been replaced, atom for atom, by an inorganic
substance, generally lime, silex, or some ore of iron. This
is the condition of the beautiful fossils from Antigua, and of
many stems and fruits from rocks of all ages in Britain.

Carbonised vegetables, or those w^hich have passed into
the state of Lignites, often undergo modifications which
render it difiicult to understand them rightly. Sometimes
a portion of the organs of vegetables which have passed into
the state of lignite is transformed into pyrites, or else pyrites
of a globular shape is found in the middle of the tissue, and
may be taken for a character of organisation. The section of
certain Dicotyledonous fossil woods, in that case, may resemble
Monocotyledons. Petrifaction, as in the case of silicified

10 PAL^ONTOLOGICAL BOTANY.

woods, often preserves all the tissues equally, at other times
the soft tissues are altered or destroyed ; the cellular tissue
being replaced by amorphous chalcedony, while the ligneous
and vascular tissues alone are petrified, so as to preserve their
forms. In some cases the reverse takes place as to these tissues;
the fibrous portions disappear, leaving cavities, while the cells
are silicified. Sometimes we find the parts regularly silicified
at one place, so as to retain the structure, while at another
an amorphous mass of silica is found. In such cases there
appear, as it were, distinct silicified woody bundles in the
midst of an amorphous mass. The appearance depends, how-
ever, merely on irregular silicification or partial petrifaction.
Infiltrated fossil woods, by means of chemical tests, are shown
to possess portions of vegetable tissues cemented into a mass
by silica. In some cases we find the vessels and cells sepa-
rately silicified, without being crushed into a compact mass.
In these cases, the intercellular substance not being silicified,
the mass breaks down easily ; whereas, when complete silicifi-
cation takes place, the mass is not friable. Coniferous wood
is often friable, from silicified portions being still separated
from each other by vegetable tissue more or less entire.
During silicification, or subsequent to it, it frequently hap-
pens that the plant has been compressed, broken, and de-
formed, and that fissures have been formed which have been
subsequently filled with crystallised or amorphous silica.

Silicified stems of trees have been observed in various
parts of the world, with their structure well preserved, so that
their Endogenous and Exogenous character could be easily
determined. The Rev. W. B. Clarke notices the occurrence
of a fossil pine-forest at Kurrur-Kurran, in the inlet of
Awaaba, on the eastern coast of Australia. In the inlet there
is a formation of conglomerate and sandstone, with sub-
ordinate beds of lignite — the lignite forming the so-called
Australian coal. Throughout the alluvial flat, stumps and

MODE OF PRESERVATION OF FOSSIL PLANTS.

11

stools of fossilised trees are seen standing out of the ground,
and one can form no better notion of their aspect than by
imagining what the appearance of the existing living forest of
Eucalypti and Casuarinas would be if the trees were all cut
down to a certain level. In a lake in the vicinity there are
also some fossilised stumps of trees, standing vertically. In
Derwent Valley, Van Diemen's Land, fossil silicified trees, in
connection with trap rocks, have been found in an erect posi-
tion. One was measured with a stem 6 feet high, a circum-
ference at the base of 7 feet 3 inches, and a diameter at the
top of 15 inches. The stems are Coniferous, resembling
Araucaria. The outer portion of the stem is of a rich brown
glossy agate, while the interior is of a snowy whiteness. One
hundred concentric rings have been counted. The tissue falls
into a powdery mass. Silica is found in the inside of the
tubes, and their substance is also silicified. The erect silici-
cificd stems of coniferous trees exist in their natural positions
in the ^^ dirt-bed," an old surface soil in the sandstone strata
of the Purbeck series in the Isle of Portland, Dorsetshire.
In the petrified forests near Cairo silicified stems have been
examined by Brown,
Unger, and Carruthers.
They belong to dicoty-
ledonous trees (not
coniferous), to which
the names of Nicolia
iEgyptiaca and Nicolia
Owenii (Fig. 7) have
been given. The wood
consists of a slender
prosenchyma, abundantly penetrated by large ducts. The
walls of the ducts are marked by small, regularly arranged,
oval, and somewhat compressed hexagonal reticulations. The
Fig. 7. Nicolia Owenii (Carr.), from the Tertiary Strata of Egypt.

Fig. 7.

12 PAL^ONTOLOGICAL BOTANY.

ducts have transverse diaphragms. There are numerous
medullary rays. The wood in their stems is converted into
chalcedony. (Carruthers on Petrified Forest near Cairo.
Geol. Mag., July 1870.)

Examination of the Structure of Fossil Plants.

When the structure of fossil plants is well preserved, it
may be seen under the microscope by making thin sections
after the mode recommended by Mr. William Nicol, the
inventor of the prism which bears his name, and to whose
memory Unger dedicated the genus Nicolia, which has just
been described as constituting the petrified forest at Cairo.
The following is a description of the process of preparing
fossils for the microscope, by Mr. Alexander Bryson. (Edin.
N. Phil. Journal, N. S. iii. 297. Balfour's Botanist's Com-
panion, p. 30.)

^' The usual mode of proceeding in making a section of
fossil wood is simple, though tedious. The first process is
to flatten the specimen to be operated on by grinding it on a
flat lap made of lead charged with emery or corundum
powder. It must now be rendered perfectly flat by hand on
a plate of metal or glass, using much finer emery than in the
first operation of grinding. The next operation is to cement
the object to the glass plate. Both the plate of glass and
the fossil to be cemented must be heated to a temperature
rather inconvenient for the fingers to bear. By this means
moisture and adherent air are driven off", especially from the
object to be operated on. Canada balsam is now to be
equally spread over both plate and object, and exposed again
to heat, until the redundant turpentine in the balsam has
been driven off" by evaporation. The two surfaces are now to
be connected while hot, and a slow circular motion, with
pressure, given either to the plate or object, for the purpose
of throwing out the superabundant balsam and globules of

EXAMINATION OF STRUCTURE OF FOSSIL PLANTS. 13

included air. The object should be below and the glass plate
above, as we then can see when all the air is removed, by the
pressure and motion indicated. It is proper to mention that
too much balsam is more favourable for the expulsion of the
air-bubbles than too little. When cold, the Canada balsam
will be found hard and adhering, and the specimen fit for
slitting. This process has hitherto been performed by using
a disc of thin sheet-iron, so much employed by the tinsmith,
technically called sheet-tin. The tin coating ought to be
partially removed by heating the plate, and when hot rubbing
off much of the extraneous tin by a piece of cloth. The plate
has now to be planished on the polished stake of the tinsmith,
until quite flat. If the plate is to be used in the lathe, and
by the usual method, it ought to be planished so as to i:>ossess
a slight convexity. This gives a certain amount of rigidity to
the edge, which is useful in slitting by the hand ; while by
the method of mechanical slitting, about to be described, this
convexity is inadmissible. The tin plate, when mounted
on an appropriate chuck in the lathe, must be turned quite
true, with its edge slightly rounded and made perfectly smooth
by a fine-cut file. The edge of the disc is now to be charged
with diamond powder. This is done by mingling the diamond
powder with oil, and placing it on a piece of the hardest
agate, and then turning the disc slowly round. Then, by
holding the agate with the diamond powder with a moderate
pressure against the edge of the disc, it is thoroughly charged
with a host of diamond points, becoming, as it were, a saw
with invisible teeth. In pounding the diamond, some care is
necessary, as also a fitting mortar. The mortar should be
made of an old steel die, if accessible ; if not, a mass of steel,
slightly conical, the base of which ought to be 2 inches in dia-
meter, and the upper part 1 J inch. A cylindrical hole is now
to be turned out in the centre, of fths of an inch diameter,
and about 1 inch deep. This, when hardened, is the mortar ;

14

PAL^ONTOLOGICAL BOTANY.

for safety it may be annealed to a straw colour. The pestle
is merely a cylinder of steel, fitting the hollow mortar but
loosely, and having a ledge or edging of an eighth of an inch
projecting round it, but sufficiently raised above the upper
surface of the mortar, so as not to come in contact while
pounding the diamond. The point of the pestle ought only
to be hardened and annealed to a straw colour, and should
be of course convex, fitting the opposing and equal concavity
of the mortar. The purpose of the projecting ledge is to
prevent the smaller particles of diamond spurting out when
the pestle is struck by the hammer."

Mr. Bryson has contrived an instrument for slitting fossils.
The instrument is placed on the table of a common lathe,

Fig. 8.

which is, of course, the source of motion (Fig. 8). It con-
Fig. 8. Mr. Bryson's instrument for slitting fossils. A very simple
slicing and polishing machine has been invented by Mr. J. B. Jordan of
the Mining Record Office, and is sold by Messrs. Cotton and Johnson,
Grafton Street, Soho, London. It costs about £10.

EXAMINATION OF STRUCTURE OF FOSSIL PLANTS. 15

sists of a Watt's parallel motion, with four joints, attaclied
to a basement fixed to the table of the lathe. This base has
a motion (for adjustment only) in a horizontal plane, by
which we may be enabled to place the upper joint in a parallel
plane with the spindle of the lathe. This may be called the
azimuthal adjustment. The adjustment, which in an astro-
nomical instrument is called the plane of right ascension, is
given by a i)ivot in the top of the base, and clamped by a
screw below. This motion in right ascension gives us the
power of adjusting the perpendicular planes of motion, so
that the object to be slit passes down from the circumference
of the slitting-plate to nearly its centre, in a perfectly parallel
plane. When this adjustment is made accurately, and the
slitting-plate well primed and flat, a very thin and parallel
slice is obtained. This jointed frame is counteqioised and
supported by a lever, the centre of which is movable in
a pillar standing perpendicularly from the lathe table.
Attached to the lever is a screw of three threads, by which
the counterpoise weight is adjusted readily to the varying
weight of the object to be slit and the necessary pressure
required on the edge of the slitting-plate.

The object is fixed to the machine by a pneumatic chuck.
It consists of an iron tube, which passes through an aperture
on the upper joint of the guiding-frame, into which is screwed
a round piece of gun-metal, slightly hollowed in the centre,
but flat towards the edge. This gun-metal disc is perforated
by a small hole communicating with the interior of the iron
tube. This aperture permits the air between the glass plate
and the chuck to be exhausted by a small air-syringe at the
other end. The face of this chuck is covered with a thin film
of soft india-i-ubber not vulcanised, also perforated with a
small central aperture. When the chuck is properly adjusted,
and the india-rubber carefully stretched over the face of the
gun-metal, one or two pulls of the syringe-piston is quite

16 PAL^ONTOLOGICAL BOTANY.

sufficient to maintain a very large object under the action of the
slitting-plate. By this method no time is lost ; the adhesion
is made instantaneously, and as quickly broken by opening a
small screw, to admit air between the glass plate and the
chuck, when the object is immediately released. Care must
be taken, in stretching the india-rubber over the face of the
chuck, to make it very equal in its distribution, and as thin
as is consistent with strength. When this material is obtained
from the shops, it presents a series of slight grooves, and is
rather hard for our purpose. It ought, therefore, to be
slightly heated, which renders it soft and pliant, and in this
state should now be stretched over the chuck, and a piece of
soft copper wire tied round it, a slight groove being cut in the
periphery of the chuck to detain the wire in its place.
When by use the surface of the india-rubber becomes flat,
smooth, and free from the grooves which at first mar its use-
fulness, a specimen may be slit of many square inches, with-
out resort being had to another exhaustion by the syringe.
But when a large, hard, siliceous object has to be slit, it is
well for the sake of safety to try the syringe piston, and
observe if it returns forcibly to the bottom of the cylinder,
which cAddences the good condition of the vacuum of the
chuck.

After the operation of slitting, the plate must be removed
from the spindle of the lathe, and the flat lead lap substituted.
The pneumatic chuck is now^ to be reversed, and the specimen
placed in contact with the grinder. By giving a slightly
tortuous motion to the specimen, that is, using the motion of
the various joints, the object is ground perfectly flat when
the length of both arms of the joints is perfectly equal.
Should the leg of the first joint on the right-hand side be the
longer, the specimen will be ground hollow ; if shorter, it
will be ground convex. But if, as before stated, they are of
equal length, a perfectly parallel surface will be obtained.

EXAIMINATION OF STRUCTURE OF FOSSIL PLANTS. 17

In operating on siliceous objects, I have found soap and
water quite as speedy and efficacious as oil, which is generally
used ; while calcareous fossils must be slit by a solution of
common soda in water. This solution of soda, if made too
strong, softens the india-rubber on the face of the pneumatic
chuck, and renders a new piece necessary; but if care is
taken to keep the solution of moderate strength, one piece of
india-rubber may last for six months. The thinner and
flatter it becomes, the better hold the glass takes, until a
puncture occurs in the outer portion, and a new piece is
rendered necessary.

The polishing of the section is the last operation. This is
performed in various ways, according to the material of which
the organism is composed. If siliceous, a lap of tin is to be
used, about the same size as the grinding lap. Having turned
the face smooth and flat, a series of very fine notches are to
be made all over the surface. This operation is accomplished
by holding the edge of an old dinner-knife almost perpendi-
cular to the surface of the lap while rotating ; this produces
a series of cridcUes, or slight asperities, which detain the
polishing substance. The polishing substance used on the
tin lap is technically called lapidaries' rot-stone, and is
applied by slightly moistening the mass, and pressing it firmly
against the polisher, care being taken to scrape off the outer
surface, which often contains grit. The specimen is then to
be pressed w4th some degree of force against the revolving'
tin lap or polisher, carefully changing the plane of action, by
moving the specimen in various directions over the surface.

To polish calcareous objects, another method must be
adopted as follows : —

A lap or disc of willoAV wood is to be adapted to the
spindle of the lathe, three inches in thickness, and about the
diameter of the other laps (10 inches), the axis of the wood
being parallel to the spindle of the lathe, that is, the acting

c

18 PAL^ONTOLOGICAL BOTANY.

surface of tlie wood is the end of the fibres, the section
being transverse.

This polisher must be turned quite flat and smoothed by
a plane, as the willow, from its softness, is peculiarly difficult
to turn. It is also of consequence to remark that both sides
should be turned, so that the lap, when dry, is quite parallel.
This lap is most conveniently adapted to the common face
chuck of a lathe with a conical screw, so that either surface
may be used. This is made evident, when we state that this
polisher is always used moist, and, to keep both surfaces
parallel, must be entirely plunged in water before using, as
both surfaces must be equally moist, otherwise the dry surface
will be concave and the moist one convex. The polishing
substance used with this lap is putty powder (oxide of tin),
which ought to be well washed, to free it from grit. The
calcareous fossils being finely ground, are speedily polished
by this method. To polish softer substances, a piece of cloth
may be spread over the wooden lap, and finely-levigated
chalk used as a polishing medium.

In order to study fossil plants well, there must be an
acquaintance with systematic botany, a knowledge of the
microscopical structure of all the organs of plants, such as
their roots, stems, barks, leaves, fronds, and fi'uit; of the
markings which they exhibit on their different surfaces, and
of the scars which some of them leave when they decay. It
is only thus we can expect to determine accurately the living
affinities of the fossil. Brongniai't says, that before compar-
ing a fossil vegetable with living plants, it is necessary to
reconstruct as completely as possible the portion of the plant
under examination, to determine the relations of these por-
tions to the other organs of the same plant, and to complete
the plant if possible, by seeing whether, in the fossils of the
same locality, there may not be some which belong to the
same plant. The connection of the different parts of the

EXAMINATION OF STRUCTURE OF FOSSIL PLANTS. 19

same plant is one of the most important problems in Palaso-
phytology, and the neglect of it has led to many mistakes.
In some instances the data have been sufficient to enable
botanists to refer a fossil plant to a genus of the present
day, so that we have fossil species of the genera Ulmus,
Alnus, Pinus, etc. Sometimes the plant is shown to be allied
to a living genus, but differing in some essential point, or
wanting something to complete the identity, and it is then
marked by the addition of the term ites, as Pinites, Thuites,
Zamites, etc.

Before drawing conclusions as to the climate or physical
condition of the globe at different geological epochs, the
botanist must be well informed as to the vegetation of
different countries, as to the soils and localities in which
certain plants grow, whether on land or in the sea, or in
lakes, in diy or marshy ground, in valleys or on mountains,
or in estuaries, in hot, temperate, or cold regions. Great
caution must be employed also in predicating from one species
the conditions of another, inasmuch as different species of
the same genus frequently exist in very different habitats,
and under almost opposite conditions of moisture and tem-
perature. It is only by a careful consideration of all these
particulars that any probable inferences can be drawn as to
the condition of the globe. Considering the physiognomy of
vegetation at the present day, we find remarkable associations
of forms. The Palms, although generally characteristic of very
warm countries, are by no mearis confined to them ; Cha-
mgerops humilis extending to Europe as far as lat. 43° to 44°
N., and C. palmetto in North America to lat. 34° to 36° N.,
while C. Fortunei, from the north of China, is perfectly hardy
in the south of England. Major Madden mentions the
association of Palms and Bamboos with Conifers at consider-
able elevations on the Himalayas. (Edin. Bot. Soc. Trans,
iv., p. 185.) Epiphytic Orchids, which usually characterise

20 PAL^EONTOLOGICAL BOTANY.

warm climates, liave representatives at great elevations, as
Oncidium nubigenum at 14,000 feet in the Andes, and Epi-
dendrum frigidimi at from 12,000 to 13,000 feet in the
Columbia momitains. These facts point out the care neces-
sary before drawing conclusions as to the climate which fossil
plants may be supposed to indicate.

FOSSILIFEROUS RoCKS.

The rocks of which the globe is composed are divided into
two great classes- — the Stratified or Aqueous, and the Unstra-
tified or Igneous. The stratified rocks frequently contain fossil
remains, and are then called fossiliferous ; those with no such
remains are designated non-fossiliferous or azoic. The igneous
unstratified rocks, included under the names of Granitic and
Trappean, show no appearance of animal or vegetable remains.
Those trap rocks, however, which have been formed of loose
volcanic ashes have often enclosed and preserved the remains
of plants and animals ; while even between the successive
beds of old lava-like trap rocks organic remains are some-
times found. Thus, in Antrim, near the Giant's Causeway,
deposits containing vegetable remains occur inter-stratified
with basaltic rocks. These remains are of miocene age,
and have been referred to coniferous plants, beeches, oaks,
plane trees, etc. Similar plants have been discovered in
a similar position by the Duke of Argyll in the island of
Mull. In trap rocks near Edinburgh, lignite with distinct
structure has also been detected. Silicified wood and coal,
imbedded in trap rocks, have been seen in Kerguelen's Land.
The wood is found enclosed in basalt, whilst the coal crops
out in ravines, in close contact with the overlying porphyritic
and amygdaloidal greenstone. Hooker has also seen silicified
wood, in connection with trap, in Macquarrie's Plains, in
Tasmania. Several beds of trap-tuff or ash, formed into

FOSSILIFEROUS ROCKS.

21

solid compact rock by infiltrated carbonate of lime^ occur in
the north-east of Arran, which contain numerous stems,
branches, and fruits of carboniferous plants. These represent
the remains of successive forests which grew on this locality,
and were one after the other destroyed by the ash-showers
poured forth from a neighbouring volcano during its inter-
mittent periods of activity.

Fossil remains are extremely rare in certain rocks, which,
from the changes they have undergone, have been deno-
minated Metamorphic. These include Gneiss and Mica-slate,
which are stratified rocks subsequently altered by heat and
other causes, and so completely metamorphosed that the
traces of organisms have been nearly obliterated. Never-
theless, recognisable traces of plant and animal remains have
been found in what were recently thought to be azoic rocks.
The absence of organic remains in rocks is therefore not
sufficient to enable us to state that these rocks were formed
before animals or vegetables existed.

The stratified rocks which contain fossils have been
divided into three great groups — the Pala30zoic, the Second-
ary, and the Tertiaiy, or into Pala30zoic and Neozoic groups.
The formations included under these are exhibited in the
following table, taken from Lyell's Manual of Geology : —

1. Recent.

2. Post Pliocene.

3. Newer Pliocene.

4. Older Pliocene.

5. Upper Miocene.

6. Lower Miocene.

7. Upper Eocene.

8. Middle Eocene.

9. Lower Eocene.

10. Maestricht Beds.

11. White Chalk.

12. Chloritic Series.

13. Gault.

14. Neocomian.

15. Wealden.

> Post Tertiary.

Pliocene.
Miocene.

Eocene.

Cretaceous.

Eecent.

Tertiary
or
! Cainozoic.

1

Secondary

or
Mesozoic.

JSTeozoic.

22

PAL^ONTOLOGICAL BOTANY.

16.
17.

18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.

30.
31.
32.
33.
34.
35.
36.
37.
38.

Pnrbeck Beds.

Portland Stone.

Kimmeridge Clay.

Coral Rag. J> Jurassic.

Oxford Clay.

Great or Batli Oolite.

Inferior Oolite.

Lias.

Upper Trias. ^

Middle Trias. >- Triassic.

Lower Trias. )

Permian. Permian.

Coal Measures. ")

Carboniferous lime- ^ Carboniferous.

stone. ■/

Upper ")
Middle > Dev oniau.

Secondary
or

Mesozoic.

>- Neozoic.

Lower
Upper
Lower
Upper
Lower
Upper

> Silurian.

Devonian or

Old Red

Sandstone.

Silurian.

Cambrian.

Cambrian.

Lower /

> Laurentian. Laureutian.

Primary

or
Palseozoic.

Palaeozoic.

J

Natural Orders to which Fossil Plants belong.

The plants found in different strata are either terrestrial
or aquatic, and the latter exhibit species allied to the salt and
fresh water vegetables of the present day. Their state of
preservation depends much on their structure. Cellular plants
have probably in a great measure been destroyed, and hence
their rarity ; while those having a woody structure have been
preserved. The following is the number of fossil genera and
species, as compiled from Unger's work on Pala3ophytology —
(linger, Genera et Species Plantarum fossilium, 1850).

DiCOTYLEDONES.

Genera.

Species

Thalamiflorre .

24

84

Calyciflorse

56

182

Corollifloriie

23

60

Monoclilamyde?e Angiospermoe

48

221

■ — Gymuosperma3

56

363

ORDERS OF FOSSIL PLANTS.

23

MONOCOTYLEDONES.

Petaloidese
Glumiferse

ACOTYLEDONES.

ThallogensB

Acrogense

Doubtful

Genera.

Species

38

130

5

12

31

203

121

969

35

197

437

2121

These plants are arranged in the different strata as follows : —

Palaeozoic

C Cambrian, Silu
J Carboniferous
V Permian
( Triassic
■\ Jurassic

rian, anc

. Devoni

an

73

683

Mesozoic

97
115
294

Cainozoic
Recent

^ Cretaceous
( Eocene
\ INIiocene
V Pliocene
Post-Pliocene .

183

414

496

35

31

Fossil Species . 2421

During the twenty years that have elapsed since this enu-
meration was made, the number of fossil species has been
very greatly increased. The proportion exhibited in this
table is likewise greatly altered from the enormous additions
made to the Tertiary Flora by linger, Ettingshausen, and
Heer, and from the important contributions by Principal
Dawson to the Deyonian Flora.

Among the fossil Thalamifloral Dicotyledons, Unger men-
tions species belonging to the orders —

Magnoliacece.

Anonacese.

Nympliseaceae.

Capparidacese.

MalvacejB.

Byttneriacece.

Tiliacese.

Aurautiaceae.

Malpigliiaceae,

Aceracese.

Sapindacese.

Cedrelacese.

Zygopliyllacese.

Xanthoxylaceae.

Coriariacea3.

24

PAL^ONTOLOGICAL BOTANY.

Among Calycifloral Dicotyledons-

Rosacese.

Celastracese.

Rhamnacese.

Anacardiacea3.

Amyridacese.

Leguminosse.

Calycantliacese.
Combretacese.
Melastomacese.
Myrtacese.

Among Corollifloral Dicotyledons —

Ericaceae.

Styracacese.

Ebenacese.

Aquifoliacese.

Sapotacese.

Oleaceoe.

Halorageacese.

Cucurbitacese.

Cornacese.

Loraiitbacese.

Rubiacese.

Apocynacese.
Gentianacese.

Among Monochlamydeous Angiosperms —

Nyctaginacese.

Lauracese.

Proteacese.

Aquilariacese.

Samydacese.

Santalacese.

Eiiphorbiacese.

Urticacese.

Artocarpacere.

Ceratophyllaceae.

Salicacese.

Myricacese.

Betulacese.

Altingiaceae.

Platanacea3.

Corylacese.

Juglandacese.

Rafflesiacese.

Among Monochlamydeous Gymnospenns —

Coniferse. | Taxacese. | Gnetaceae. | Cycadacese.

Among Petaloid Monocotyledons —

Smilacese. Liliaceae.

Orchidacese. Palmse,

Zingiberacese.

Pandanacese.
.ixracese.

Musacese.
Among Glumiferous Monocotyledons —

Cyperacese. |

Among Acrogenoiis Acotyledons-

Typhacese.

Naiadacese.

Restiacese.

Graminese.

Filices.
Marsileacese.

Lycopodiacese.
Equisetacese.

Miisci.
Hepaticse.

Among Thallogenous Acotyledons —

Licheues. I Characese. I Algae.

Funoji.

PERIODS OF VEGETATION AMONG FOSSIL PLANTS.

Periods of Vegetation among Fossil Plants.

On taking a general survey of the known fossil plants,
Brongniart thought that he could trace three periods of vege-
tation, characterised by the predominance of certain marked
forms of plants. In the ancient period there is a predomi-
nance of Acrogenous Ciyptogamic plants ; this is succeeded
by a period in which there is a preponderance of Gymno-
spemious Dicotyledons ; while a third period is marked by the
predominance of Angiospermous Dicotyledons. There is thus
— 1. The reign of Acrogens, which includes the plants of the
Devonian, Carboniferous, and Permian periods. During
these periods there seems to be a predominance of Ferns,
and a great development of arborescent Lycopodiacese, such
as Lepidodendron and Sigillaria, and with them are associated
some Gymnospemis, allied to Araucaria, and some anomalous
plants, as Noeggerathia. 2. The reign of Gymnospemis, com-
prehending the Triassic and Jurassic periods. Here we meet
with numerous Conifera? and Cycadaceee, while Ferns are
less abundant. 3. The reign of Angiosperms, embracing the
Cretaceous and the Tertiary periods. This is characterised
by the predominance of Angiospermous Dicotyledons, a class
of plants which constitute more than three-fourths of the
present vegetable productions of the globe, and which appear
to have acquired a predominance from the commencement of
the Tertiary formations. These plants appear sparingly even
at the beginning of the chalk formation in Europe, but are
more abundant in this formation as developed in North
America.

26 PAL^EONTOLOGICAL BOTANY.

FLORA OF THE PRIMARY OR PALAEOZOIC

PERIOD.

Reign of Ackogens.

In the present day, acrogenous i^lants are represented by
cellular and vascular Cryptogams. In considering fossil
plants our attention is specially directed to the latter. In
the recent Floras, vascular acrogens are represented by such
plants as Ferns, Lycopods, and Equisetums. Some of them
have an arborescent habit, but the greater number are shrubby
and herbaceous. Many of them have creeping rhizomes,
which are either subterranean, or run along the surface of the
ground. One of these arborescent forms is seen in Tree-ferns
(Fig. 9). Another form with a rhizome is seen in Fig. 10. The
trunks of ferns are marked by scars, which indicate the parts
where the bases of the fronds were attached, and where the
vascular tissue passes out from the interior (Fig. 11, a and 6).
A transverse section of the stem (Fig. 12) shows a continuous
cylinder of scalariform vessels (Fig. 13), enclosing a large
mass of cellular tissue frequently penetrated by small scala-
riform bundles. The cylinder is pierced by meshes, from
the inner sides of which rise the vascular bundles going to the
leaves, while some of the free bundles of the axis pass through
the mesh, carrying Avith them a portion of the cellular tissue
into the petiole. The fructification consists of spore-cases
(sporangia), often with an elastic ring round them, containing
spores in their interior (Fig. 14).

Among Acrogens of the j)resent day there are also plants
belonging to the natural order Lycopodiacea? or Club-mosses
(Fig. 15), having creeping stems, which give rise to leafy
branches. The leaves are small, sessile, and moss-like, and
the fructification consists of two kinds of cellular bodies.

FLORA OF THE PALEOZOIC PERIOD.

27

small spores or microspores (Fig. 16), and large spores or
macrospores (Fig. 17). They consist of cellular and yascular

Fig. 9.

tissues, the latter occurring in the fonn of woody, annular,
and scalariform vessels, which occupy the axis or central part
of the stem. They differ from ferns in the distribution of their
vascular bundles. The order is represented also by such plants
as Selaginella, Psilotum, Phylloglossum, and Isoetes. In the
plant called Isoetes (Quillwort) there is a peculiar short stem

Fig. 9. Tree-fern, with a slender cylindrical trunk and a crown of
drooping fronds. It is a vascular acrogen.

28

PAL^ONTOLOGICAL BOTANY.

which does not increase in height. It produces additions

Fig. 10.

laterally, so that the stem increases in thickness. The leaves

Fig. 10. Asjplenium; a species of Spleen wort. A. Rhizome, r,
covered with the bases (stalks or stipes) of the fronds ; /, fronds in
bud, rolled up in a circinate manner (this is very rarely seen in fossil
ferns) ; g, fronds bearing fructification on their backs. B. Portion of
a frond separated to show the linear sori or clusters of sporangia
(spore-cases).

FLORA OF THE PALEOZOIC PERIOD.

29

continue to multiply, and bear fructification at their bases.
They have both large and small spores.

Fig. 11, a.

Fig. 11, h.

Fig. 12.

Another important order of vascular Acrogens is the Equi-
setacea3 or Horse-tails (Fig. 18). These are Cryptogams,
having rhizomes, bearing hollow, striated branches, which
secrete in their epidermis a considerable amount of silex.
These branches are jointed and have membranous sheaths at
the articulations, which are whorls of leaves reduced to a very
rudimentary condition. The fructification consists of cone-
like bodies (Fig. 18, /) bearing peltate polygonal scales,
under which are spore-cases (Fig. 19), enclosing spores with

Fig. 11, a. Bifurcating (forked or dichotomous) trunk (caudex) of
a Tree-fern (Alsophila Perrottetiana), showing the scars (cicatrices) left
by the fallen fronds. These scars exhibit the arrangement of the vas-
cular bundles. Fig. 11, b. Rhizome of Lastrea Filix-mas (male fern),
showing scars of the leaves, c, with markings of the vascular bundles.

Fig. 12. Transverse section of the stem (caudex) of a Tree-fern
(Cyathea), showing the arrangement of the celhilar and vascular tissue.
The cellular tissue of the centre, m ; that of the circumference, p ;
vascular cylinder, / v, consisting of dark-coloured pleurenchyma or
ligneous tubes, /, and paler vessels, v, chiefly scalariform and closed
spiral, and pierced by the meshes for the leaf-bundles at m ; the outer
cortical portion connected with the bases of the leaves, e.

30 PAL^EONTOLOGICAL BOTANY.

four liygrometric club-shaped filaments called elaters (Figs. 20

Fk. 13.

Fi'4. 14.

Fiir. 16.

Fi?. 15.

Fi-. 17.

Fig. 13. Scalariform vessels taken from a Tree-fern. They are
marked with bars like the steps of a ladder, hence their name. The
membrane occasionally disappears, so that the walls are made up of
fibres only at some parts.

Fig. 14. Sporangia of a Fern, supported on stalks, p, each of
which ends in an elastic cellular ring, s, partially surrounding the
spore-case, and opening it when mature.

Fig. 15. Lycoiwdium clavatum, a common Club-moss. The leafy
branch, I, ends in a stalk bearing two spikes of fructification, /.

Fig. 16. A kidney-shaped 2-valved case, containing small spores
(microspores) of Lycopodium.

Fig. 17. Two-valved case, containing large spores (macrospores) of
Sela^inella.

FLORA OF THE PALEOZOIC PERIOD. 31

and 21). At the present day some of these plants in tropical
regions have stems of 15 or 16 feet high.

Among vascular Acrogens is included the
natural order Marsileaceas or Rhizocarpcc^, the
Pepperworts (Fig. 22). The order consists of
aquatic plants, with creeping stems, bearing
leaves, which are either linear, or divided into
three or more wedge-shaped portions not unlike
clover. The fructification is at the base of the
leaf-stalks, and consists of sacs (sporocarps) con-
taining spores of two kinds, microspores and
macrospores. The order contains Marsilea, Pilu-
laria, Azolla, and Salvinia.

For a fuller account of Acrogenous plants,
see Balfour's Class Book of Botany, p. 954. ^^^

These orders are represented in the Pala3ozoic
flora. Many of the fossil species assume a large
size, and show a greater degree of development
than is seen in their recent congeners. The most
important coal plants belong to the Ferns, Lyco-
pods, and Horse-tails. The examination of the Fig. is.
structure and conformation of the plants of the present flora
assists much in the determination of the fossil carboniferous
flora.

In the lower Pala3ozoic strata the plants which have been

detected are few^ In the Silurian and Cambrian systems, we

meet with the remains of ancient marine plants, as well as a

few terrestrial species. Even in the still older Laurentian

rocks, if the remarkable structure known as Eozoon canadense

Fig. 18. Fructification of Equisetum maximum, Great Water
Horse-tail, showing the stalk surrounded by membranous sheaths, s s,
which are fringed by numerous processes called teeth. The fructifica-
tion, /, at the extremity, is in the form of a cone bearing polygonal
scales, under which are spore-cases containing spores with fila-
ments.

32

PAL^ONTOLOGICAL BOTANY.

be considered, as it generally is, an animal, the existence of
contemporary plants may be inferred, inasmuch as without
vegetable life animals could not obtain food. In the Lower
Silurian or Grauwacke, near Girvan, Hugh Miller found
a species resembling Zostera in form and appearance. In
the Lower Old Red Sandstone of Scotland he detected
Fucoids, a Lepidodendron, and Lignite with a distinct Coni-
ferous structure resembling that of Araucaria,* besides a
remarkable pinnate frond. In the middle Old Red of For-
farshire, as seen in the Arbroath pavement, he found a

Fig. 19.

Fipr. 20.

Fiir. 21.

fern with reniform pinnas and a Lepidodendron. In the
Upper Old Red, near Dunse, a Calamite and the well-known
Irish fern Cyclopteris Hibernica occur. f This fern, Palseo-

Fig. 19. Polygonal scale, s, of a species of Horse-tail (Equisetum),
bearing membranous sacs, t, which open on their inner surface to dis-
charge spores.

Fig. 20. Spore of Equisetum, surrounded by two filaments with
club-shaped extremities. The filaments are represented as coiled round
the spore.

Fig. 21. Spore of Equisetum, with the filaments (elaters) ex-
panded.

^ Miller's Footprints of the Creator, 192-199. Doubts have been
thrown on the antiquity of this specimen by those who support the
erroneous progressive development theory ; but the presence, in the
same nodule, of a scale of a fish only found in the lower Old Ked, puts
the matter beyond doubt. Dr. M'Nab on the Structure of a Lignite
(Pal(Eopitys) from the Old Red Sandstone. (Trans. Bot. Soc. x. p. 312.)

t Specimens of these fossil plants, as well as numerous others,
illustrating the fossil flora of Scotland, are to be seen in Mr. Miller's
collection, now in the Edinburgh Museum of Science and Art.

FLORA OF THE PALEOZOIC PERIOD.

33

pteris Hibernica of Schimper (Plate I. Figs. 1 to 4), along with
Sigillaria dichotoma, is very abiiiiclant in beds of the same age
in the south of Ireland, from which the specimens described

Fig. 22.

by Edward Forbes were obtained. The fructification has re-
cently been discovered. This shows that the fern belongs to

Fig. 22. Marsilea Fahri, a species of Pepperwort or Rhizocarp,
with a creeping stem, quadrifoliate stalked leaves on one side, and
roots on the other. The fructification, s, is at the base of the leaves,
and consists of sporangia, called sporocarps.

D

34 PALiEONTOLOGICAL BOTANY.

the Hymenophyllea}, and is consequently nearly related to
the equally famous Killarney fern, Trichomanes radicans.

Mr. Carruthers states that the frond-stalk of this fern is
thick, of considerable length, and clothed with large scales,
Avhich form a dense coyering at the somewhat enlarged base.
The well-defined separation observed in several specimens
probably indicates that the frond-stalks were articulated to
the stem or freely separated from it, and some root-like
structures which occur on the slabs with the ferns may be
their creeping rhizomes. The pinn« are linear, obtuse, and
almost sessile. The i^innules are numerous, overlapping, of
an ovate or oblong- ovate form, somewhat cuneate below, and
with a decurrent base. The veins are very numerous, uni-
form, repeatedly dichotomous, and run out to the margin,
where they form a slight serration. Single pinnules rather
larger than those of the pinnae are placed over the free spaces
of the rachis, as was pointed out by Brongniart. Carruthers
has not met with any recent fern in which this occurs ; but it
has been observed in several fossil species, as in the allied
American Pala3opteris Halliana (Sch.), in Sphenopteris erosa
(Morris), and others. The pinnules are sometimes entirely, but
only partially fertile. The ovate-oblong sori are generally
single and two-lipped, the slit passing one-third of the way
down the sorus. The vein is continued as a free receptacle
in the centre of the cup or cyst, as in existing Hymenophyllea3,
in which it is included, not reaching beyond its entire i^ortion.
In some specimens the receptacle is broad or thick, indicating
the presence of something besides itself in the cup, and giving
the aj^pearance that would be produced if it were covered
with sporangia ; there is no indication on the outer surface
which might have been expected from the separate sporangia.
The compression of the specimens in the rock, which has
made the free receptacle appear like a vein on the wall of
the cup, together with the highly altered condition of the
rock in which the fossils are contained, accounts for the

FLOKA OF THE CARBONIFEROUS EPOCH. 35

imperfect preservation of the minute structures. The inter-
pretation here given of the fructification of this interesting
fossil exhibits so close a resemblance to what we find in the
living genus Hymenophyllum, that, were it not for the vege-
tative portions, it would be placed in that genus. Several
ferns have been described by Bunbury from Devonian rocks
at Oporto. A still more extensive and varied land flora of
Devonian age (or Erian, as he calls it) has been described
and illustrated by Principal Dawson from the rocks of that
period occurring in Canada ; and during a recent visit to
Britain he has correlated many of the fragments collected by
Miller, Peach, and others, with the American species he has
described. The following are some of the fossil plants from
beds older than the Carboniferous system : * — Prototaxites
Logani, Dadoxylon Ouangondianum, Calamites transitionis,
Asterophyllites parvulus, SpliQuophyllum antiquum, Lepido-
dendron Gaspianum, Lepidostrobus Richardsoni, L. IMatthewi,
Psilophyton princeps, P. robustius, Selaginites formosus,
Cordaites Robbii, C. angustifolius, Cyclopteris Jacksoni.

From the microscopic examination of the structure of
specimens of fossil trunks described under the name of Pro-
totaxites Logani, and which Principal Dawson believes to be
the oldest known instance of Coniferous wood, INIr. Carruthers
has come to the conclusion that they are really the stems of
huge Alg£e, belonging to at least more than one genus. They
are very gigantic when contrasted with the ordinary Alga? of
our existing seas, nevertheless sojiie approach to them in size
is made in the huge and tree-like Lessonias which Dr. Hooker
found in the Antarctic Seas, and which have stems about
20 feet high, with a diameter so great that they have been
collected by mariners in these regions for fuel, under the
belief that they were drift-wood. They are as thick as a man's

''^ Dawson, Jour. Geol. Soc. Lond. xv. Canadian Naturalist, v.
Acadian Geology, 2d edit. Fossil plants of the Devonian and upper
Silurian Formations of Canada, with 20 plates ; in Report of Geolo-
gical Survey of Canada.

36 PALuEONTOLOGICAL BOTANY.

thigh. Schimper regards the Psilophyton of Dawson (Plate
IV. Fig. 5) as allied to Pilularia, one of the Rhizocarps (Fig. 22),
and Carruthers ]3laces it among the true Lycopodiacea3.

The Carboniferous period is one of the most important
as regards fossil plants. The vegetable forms are numerous,
and have a great similarity throughout the whole system,
whether exhibited in the Old or the New World. The
important substance called Coal owes its origin to the
plants of this epoch. It has been subjected to great
pressure and long-continued metamorphic action, and hence
the appearance of the plants has been much altered. It
is difficult to give a definition of Coal. The varieties of it
are numerous. There is a gradual transition from Anthracite
to Household and Parrot Coal ; and the limit between Coal
and what is called bituminous shale is by no means distinct.
Coal may be said to be chemically-altered vegetable matter
interstratified with the rocks, and capable of being used as
fuel. On examining thin sections of coal under the micro-
scope, we can detect vegetable tissues both of a cellular and
vascular nature. In AVigan cannel coal, vegetable structure
is seen throughout the whole mass. Such is likewise the
case with other cannel, parrot, and gas coals. In common
household coal, also, evident traces of organic tissue have
been observed. In some kinds of coal punctated woody tissue
(Plate III. Fig. 5) has been detected, in others scalariform
tissue (Plate III. Fig. 6), as well as cells of different kinds.
Sporangia are also frequently found in the'substance of coal,
as shown by Mr. Daw in that from Fordel (Plate III. Figs.
1 to 3) ; and some beds, like the Better bed of Bradford, are
composed almost entirely of these sporangia imbedded in
their shed microspores, as has been recently shown by Huxley.
The structure of coal in different beds, and in different parts
of the same bed, seems to vary according to the nature of
the plants by which it has been formed, as well as to the
metamorj)hic action which it has undergone. Hence the

FLORA OF THE CARBONIFEROUS EPOCH. 37

different yarieties of coal which are worked. The occur-
rence of punctated tissue indicates the presence of Coni-
fera3 in the coal-bed, while scalariform vessels point to ferns,
and their allies, such as Sigillaria and Lepidodendron. The
anatomical structure of the stems of these plants may have
some effect on the microscopic characters of the coal pro-
duced from them. In some cannel coals structure resembling
that of Acrogens has been observed. A bro^vnish -yellow
substance is occasionally present, which seems to yield abund-
ance of carburetted hydrogen gas when exposed to heat.

It appears that in general each bed of coal is accompanied
by the remains of a somewdiat limited amount of species.
Their number, particularly in the most ancient beds, is scarcely
more than eight or ten. In other cases the number is more
considerable, but rarely more than thirty or forty. In the
same coal-basin each layer often contains several characteristic
species which are not met with either in the beds above or
below. Thus, there are sometimes small local or temporary
floras, each of which has given birth to layers of coal. The
quantity of carbonaceous and other matter required to form
a bed of coal is immense. Maclaren has calculated that one
acre of coal three feet thick is equal to the produce of 1940
acres of forest.* The proportion of carbon varies in different
kinds of coal. Along with it there is always more or less of
earthy matter which constitutes the ashes. When the earthy
substances are in such quantity that the coaly deposit will
not burn as fuel, then we have what is called a shale. The
coal contains plants similar to those of the shales and sand-
stones above and below it. Underneath a coal-seam lies
the Underclay, containing roots only, and representing the
ancient soil ; then comes the Coal, composed of plants whose
roots are in the clay, Tvith others which have grown along with
and upon them, in a manner precisely similar to the growth of
peat at the present day ; while above the coal is the Shale,

''' Mat'lareu, Geology of Fife and the Lothiaus, p. 11 G.

38

PALi^ONTOLOGICAL BOTANY.

marking how mud was laid down on the plants, and bearing
evidences of vigorous vegetation on neighbouring land, from
which currents brought down the fine sediment, mingled with
broken pieces of plants.

The total thickness of coal in the English coal-fields is
about 50 or 60 feet. In the Mid-Lothian field there are
108 feet of coal. Coal-beds are Avorked at 1725 feet below
the sea-level, and probably extend down to upwards of
20,000 feet. They rise to 12,000 feet above the sea-level,
and at Huanuco, in Peru, to 14,700.* It is said that the
first coal-works were opened at Belgium in 1198, and soon
after in England and Scotland ; it was not till the fifteenth
century that they were opened in France and Gennany.

The following calculations have been made as to the extent
of the coal formation in difierent countries, and the amount
of coal raised : — "f*

Cou:n'tries.

Square Miles of
Coal Formation.

Great Britain and Ireland

British North America

United States

Belgium

France

Prussia and Austria

Saxony

Eussia

Japan, China, Borneo, Australia, etc.

Total Produce of the World...

5,400

7,530

196,650

518

1,719

30
100

Annual Production
of Coal in Tons. \

65,887,900
1,500,000
5,000,000
8,409,330
7,740,317
4,200,000
1,000,000
3,500,000
2,000,000

99,237,547

The total quantity of coal annually raised over the globe ap-
pears thus to be about 100 millions of tons, of which the produce
of Great Britain is more than two-thirds, and would be sufficient
to girdle the earth at the equator with a belt of 3 feet in thick-
ness and nearly 5 feet in width. The coal-fields of the United
States are nearly forty times larger than those of Great Britain.

* Our Coal-fields, by a Traveller under Ground.

t See Hall's Coal-fields of Great Britain, 18G1 ; Roscoe's Lec-
tures on Coal, Manchester, 18G6-67 ; Hunt's Mineral Statistics of
Great Britain; Taylor's Statistics of Coal, 1855-56.

FLORA OF THE CARBONIFEROUS EPOCH.

39

Roscoe gives the following estimated quantities of coal
iu the principal countries : —

CorSTRIES.

Average Tliickness.
No. Feet.

Tons.

Belgium

France

British Islands

60
60
35
25
25
25
10

20

36,000,000,000

59,000,000,000

190,000,000,000

316,400,000,000

1,3S7,500,000,000

l.-277,500,000,000

739,000,000,000

4,000,000,000,000

Pennsylvania

Great Appalachian Coalfield

Indiana, Plinois, Western Kentucky

Missoui'i, and Arkansas Basin

North America (assumed thickness
over an area of 200,000 square
miles)

Unger enumerates 683 plants of the coal-measures, while
Brongniart notices 500. Of the last number there are 6
Thallogens, 346 Acrogens, 135 Gvmnospenns, and 13 doubt-
ful plants. This appeai-s to be a very scanty yegetation, as for
as regards the number of species. It is only equal to about
l-20th of the number of species now growing on the sui-fiice
of the soil of Europe. Although, however, the number of
species was small, yet it is probable that the individuals of a
species were numerous. The proportion of Ferns was very
lai'ge. There are between 200 and 300 enumerated. Schimper
thinks there are 7 species congeneric mth Lycopodium found
in tlie coal-measures. The following are some of the Crypto -
gamous and Phanerogamous genera belonging to the flora
of the Carboniferous period : — Cyclopteris, Xeuropteris,
Odontopteris, Sphenopteris, H}inenophyllites, Alethopteris,
Pecopteris, Coniopteris, Cladophlebis, Seuftenbei'gia, Lon-
chopteris, Glossopteris, Caulopteris, Lepidodendron (Lepido-
strobus, Lepidophyllum, Knorria), Flemingites, Ulodcudron,
Halonia, Psaronius, Sigillaria and Stigmaria, Calamites
(Asterophyllites and Sphenophyllum), Xoeggerathia, Walchia,
Peuce, Dadoxylon, Pissadcndron, Trigonocarpum.

Ferns are the carboniferous fossil group which present the
most obvious and recognisable relationship to plants of the
present day. While cellular plants and those with lax tissues

40 PALJEONTOLOGICAL BOTANY.

have lost their characters by the maceration to which they
were subjected before fossilisation took place, ferns are more
durable, and retain their structure. It is rare, howeyer, to
find the stalk of the frond completely preserved down to its
base. It is also rare to find fructification present. In this
respect, fossil Ferns resemble Tree-ferns of the present day,
the fronds of which rarely exhibit fructification. Hooker
states that of two or three kinds of New Zealand Tree-fern,
not one specimen in a thousand bears a single fertile frond,
though all abound in barren ones. Only one surface of the fossil
Fern-frond is exposed, and that generally the least important
in a botanical point of view. Fructification is sometimes evi-
dently seen, as figured by Corda in Senftenbergia. In this case
the fructification is not unlike that of Aneimidictyon of the
present day. Carruthers has recently detected the separate
sporangia of Ferns full of spores in calcareous nodules in
coal (Plate I. Fig. 5). These have the elastic ring character-
istic of the Polypodiacea3, and in their size, form, and method
of attachment, they are allied to the group Hymenophylleas.
The absence of fructification presents a great obstacle to the
determination of fossil Ferns. Circinate vernation, so com-
mon in modem Ferns, is rarely seen in the fossil species, and
we do not in general meet with rhizomes. Characters taken
from the venation and forms of the fronds are not always to
be depended upon, if we are to judge from the Ferns of the
present day. There is a great similarity between the carboni-
ferous Ferns of Britain and America ; and the same species,
or closely allied species of the same genera as those found in
Britain have been met with in South Africa, South America,
and Australia. In the English coal-measures the species are
about 140. The PalaBozoic flora of the Arctic regions also
resembles that of the other quarters of the globe. Heer, in
his account of the fossil flora of Bear Island,* enumer-
ates the following plants : — Cardiopteris frondosa, C. poly-

'^ Heer, Flora fossilis Arctica; Fossile Flora der Biiren Insel., 1871.

FLORA OF THE CARBONIFEROUS EPOCH.

41

morplia, Palasopteris Roenieriana, Sphenopteris Schimperi,
Lepidodendroii Yeltheimianiim, L. commutatum, L. Cariieg-
giannum, L. Wilkianum, Lepidopliylliim Roemeri, Knorria
imbricata, K. acicularis, Calamites radiatiis, Cyclostigma
Kiltorkense, Stigmaria ficoides, etc., Cardiocarpiim ursiuum,
C. punctulatum, besides various sporangia and spores.

The preponderance of Ferns over flowering plants is seen
at the present day in many tropical islands, such as St.
Helena and tbe Society group, as well as in extra-tropical
islands, as New Zealand. In the latter. Hooker picked 36
kinds in an area of a few acres ; they gave a luxuriant aspect
to the vegetation, which presented scarcely twelve flowering
plants and trees besides. An equal area in the neighbour-
hood of Sydney (in about the same latitude) would have
yielded upwards of 100 flowering plants, and only two or
three Ferns. This Acrogenous flora,
then, seems to favour the idea of a
humid as well as mild and equable
climate at the period of the coal
formation — the vegetation being that
of islands in the midst of a vast
ocean. Lesquereux, in Silliman's
Journal, gives three sections of Ferns
in the Carboniferous strata — viz.
Neuropteridea3, Pecopteridea3, and
Sphenopteridea3. In Neuropteridea;
fructification has been seen in Odon-
topteris. In this genus the spores
are in a peculiar bladdery sporan-
gium. In Neuropteridea3 the fructification appears to have
resembled Dana?a in some cases, and Osmunda in others.
Professor Geikie has noticed in the lower Carboniferous
shales of Slateford, near Edinburgh, a fern which has been
named Adiantites Lindseasformis by Bunbury (Fig. 22, his).
Fig. 22, his. Adiantites Lindseseformif?.

Fi<?. 22, bis.

42 PAL^ONTOLOGICAL BOTANY.

It has pinnules between crescent and fan shaped. (Mem.
Geol. Survey of Edinburgh, 1861, p. 151.)

Among the Ferns found in the clays, ironstones, and sand-
stones of the Carboniferous period, we shall give the characters
of some by way of illustration.* Pecopteris (Fig. 23) seems to
be the fossil representative, if not congener, of Pteris. Peco-
pteris heterophylla (Fig. 24) has a marked resemblance to
Pteris esculenta of New Zealand. The frond of Pecopteris
is pinnatifid, or bi-tri-pinnatifid — the leaflets adhering to the
rachis by the whole length of their base, sometimes confluent ;
the midrib of the leaflets runs to the point, and the veins
come off" from it nearly perpendicularly, and the fructification
when present is at the end of the veins. Neuropteris (Figs.
25, 26, 27) has a pinnate or bipinnate frond, with pinna3
somewhat cordate at the base — the midrib of the pinnge
vanishing towards the apex, and the veins coming off* obliquely,
and in an arched manner. Neuropteris gigantea (Fig. 26)
has a thick bare rachis, according to Miller, and seems to
resemble much Osmunda regalis. Odontopteris has leaves
like the last, but its leaflets adhere to the stalk by their whole
base, the veins spring from the base of the leaflets, and pass
on towards the point. Splienopteris (Fig. 28) has a twice or
thrice pinnatifid frond, the leaflets being narrowed at the
base, often wedge-shaped, and the veins generally arranged as
if they radiated from the base. Splienopteris elegans resem-
bled Pteris aquilina in having a stout leafless rachis, which
divided at a height of seven or eight inches from its club-like
base into two equal parts, each of which continued to undergo
two or three successive bifurcations. A little below the first
forking two divided pinna3 were sent off: A very complete
specimen, with the stipe, w^as collected in the coalfield near

■'''■ In giving names to fossil Ferns, the Greek word -Trrs^lg, meaning
a Fern, is often used with a prefix indicating some character in the
form of the leaves, or stem, or fructification : such as, 'ttUoc, a comb ;
vs-j^ov, a nerve; odovg, a tooth; 6(priv, a wedge; zavXog, a stalk or
stem ; '/.vaXog, a circle ; ^X'^^^} ■"• ^pli^ ^^^-

FLORA OF THE CARBONIFEROUS EPOCH.

43

Edinburgh by Hugh Miller, who has described it as above.
Lonchopteris has its frond multi-j^innatifid, and the leaflets
more or less united together at the base ; there is a distinct
midrib, and the veins are reticulated. Cyclopteris (Fig. 29) has
simple orbicular leaflets, undivided or lobed at the margin,
the veins radiating from the base, with no midrib. Schizo-
pteris resembles the last, but the frond is deeply divided into

Fig. 23. Fig. 25. Fig. 26. Fig. 27.

numerous unequal segments, which are usually lobed and

taper-pointed.

The rarity of Tree-ferns in the coal-measures has often

been observed, and it is the more remarkable from the durable

nature of their tissues. Several species have, however, been

noticed. They are referred to the genus Caulopteris. One

of them, C. macrodiscus (Fig. 30) has the leaf-scars in linear

series. Two other species are figured, the one a slender form

Fio's. 23 to 29 exhibit the fronds of some of the Ferns of the
Carboniferous epoch. Fig. 23. Pecopteris (^Alethoioteris) aquilina.
Fig. 24. Pecopteris (Alethopteris) heterophylla. Fig. 25. Neuropteris
Loshii. Fig. 26. Neurop>teris gigantea. Fig. 27. Neuropteris acuminata.
Fig. 28. Sphenopteris affinis. Fig. 29. Cyclopteris clilatata.

44

PAL^ONTOLOGICAL BOTANY.

with the scars widely separated^ as in some Alsophilas, C. Bal-
fouri (Fig. 31) from the Somersetshire coal-field ; and the other
with larger stems and more closely aggregated scars, C. Morrisi
(Fig. 32), from the coal-measures at Newcastle. The latter
species shows the cavities at the base of the petiole described
by Mohl in many living fern-stems. The fossils named Psa-
ronius appear to have been fern-stems with a slender axis and
a large mass of adventitious roots, as in some Dicksonias and
in Osmunda regalis. These stems probably belong to some of
the fronds to which other names are given, but as they have

Fig. 30. Fig. 31. Fig. 32.

not been found attached, it is impossible to determine the
point. Miller has described a fern as occurring in the coal-
measures, which at first sight presents more the appearance
of a Cycadaceous frond than any other vegetable organism
of the carboniferous age except the Cycadites Caledonicus
(Salter), from Cockburnspath Cove. He thus describes it : —
"From a stipe about a line in thickness there proceed at.

Figs. 30 to 32. Stem of Tree-ferus, called Caulopteris. Fig. 30.
Caulopteris macrodiscus. Fig. 31. Caidopteris BaJfouri (Carr.), Coal-
measures. Fig. 32. Caulopteris Morrisi (Carr.), Coal-measures.

FLORA OF THE CARBONIFEROUS EPOCH.

45

right angles, and in alternate order, a series of sessile lanceo-
late leaflets, rather more than two inches in length, by abont
an eighth part of an inch in breadth, and about three lines
apart. Each is furnished mth a slender midrib ; and,
what seems a singular, though not entirely unique feature in
a Fern, the edges of each are densely hirsute, and bristle
with thick short hair. The venation is not distinctly pre-
served."

Sigillaria (Plate IV. Figs. 1 and 2) is perhaps the most
important plant in the coal formation. The name is derived
from sigillum, a seal, to indicate the seal-like markings in the
stem. It is found in all coal-shales over the world. Schim-

Shale

ri£c. 33.

Fi^. 34.

per mentions 83 species. It occurs in the form of lofty
stems, 40-50 feet high, and 5 feet broad (Figs. 33 and 34).
Many stems of Sigillaria may be Seen near Morpeth, standing
erect at right angles to the planes of alternating strata of
shale and sandstone (Fig. 33). They vary from 10 to 20 feet
in height, and from one to three feet in diameter. Sir W. C.

Figs. 33 to 37 exhibit forms of Sigillaria stems found in the
shales of the Carboniferous epoch. Fig. 33. Stem of Sigillaria ixichy-
clerma in an erect position, covered by successive deposits of sandstone
and shale ; one of the stems is bifurcated. Fig. 34. Sigillaria reni-
formis, with its external markings, and roots which are Stigmarias, as

46

PAL^ONTOLOGICAL BOTANY.

Trevelyan counted 20 portions of these trees witliin the length
of half-a-mile, of which all but four or five were upright.

Bronsfniart mentions similar

erect stems as being found
near St. Etienne. The stem
of Sigillaria is fluted in a
longitudinal manner, like a
Doric column, and has a suc-
cession of single scars, which
indicate the points of inser-
tion of the leaves (Figs. 35,
36, and 37). When the
outer part of the stem sepa-
rates like bark, it is found that
the markings presented by
the inner surface differ from
those seen externally. This has sometimes given rise to

Fiaf. 36.

Fit?. 37.

the erroneous multiplication of species and even of genera.

proved by Mr. Binney. Fig. 35. Sigillaria 2')achydemia, after Lindley
and Hutton, from the shale of Killingworth Colliery, showing the
scars or places through which the vessels of the stem passed to the
leaves. Fig. 36. Sigillaria (Favularia) tessellata, from the Denbigh
coal-shale, showing the fluted stem with scars. Fig. 37. Sigillaria
pachyderma ; the stem marked with scars, and fluted longitudinally.

FLORA OF THE CARBONIFEROUS EPOCH.

47

Sigillaria elegans, as figured hj Brongniart in Archives du
Museum, i. 405, has a stem consisting of a central cellular axis
or medulla, surrounded by a vascular cylinder, and this is in-
vested by a thick cellular cortical layer, the outer portion com-
posed of fusifonii cells of less diameter than those of the inner
portion. What Brongniart calls medullary rays are mere cracks
or separations in the wedges traversed by vessels. In its
structure it resembles its root Stigmaria, and must be referred
to Lycopodiacea3, along with Lepidodendron, Halonia, Ulo-
dendron, etc. The small round sporangia of Sigillaria are

Fi?. 38.

Fiff. 39.

borne in a single patch on the somewhat enlarged bases of
some of the leaves. (See Carruthers on Structure and Affini-
ties of Sigillaria, in Journ. Geol. Soc. Aug. 1869.)

It has been ascertained by Professor King and Mr. Binney
of ^lanchester, that the plant called Stigmaria (Fig. 38) is not a
separate genus, but the root of Sigillaria (Plate IV. Figs. 1 and
2). The name is derived from oTty/xa, a mark, indicating the
markings on the axis. It is one of the most common produc-
tions of the coal-measures, and consists of long rounded or
compressed fragments, marked externally by shallow circular,

Fig. 38. Stigmaria ficoides, root of Sigillaria, giving off rootlets,
which have been compressed.

Fig. 39. Stigmaria ficoides (S. Anahatlira of Corda), which is the root
of a Sigillaria. The markings are the points whence rootlets proceed.

48 PAL^ONTOLOGICAL BOTANY.

oblong, or lanceolate cavities (Fig. 39) in the centre of slight
tubercles, arranged more or less regularly in a quincuncial
manner (Plate III. Fig. 7). The canities occasionally present
a radiating appearance. The axis of the fragments is often
hollow, and different in texture from the parts around. This
axis consists of a vascular cylinder or woody system, penetrated
by quincuncially arranged meshes or openings, through which
the vascular bundles proceed from the inner surface of the
cylinder to the rootlets (Plate III. Figs. 8 and 9). From the
scars and tubercles arise long ribbon-shaped processes, which
were cylindrical cellular roots, now compressed (Fig. 38). The
vascular cylinder of Stigmaria is composed entirely of scalari-
form tissue, pierced by meshes for the passage, from the inner
surface of the cylinder, of the vascular bundles which supply
the rootlets. (Carruthers in Geol. Proc, Aug. 1869.) Stig-
maria ficoides (Fig. 38) abounds in the under-clay of a coal-
seam, sending out numerous roots from its tubercles, and
pushing up its aerial stem, in the form of a fluted Sigillaria.
On the Bolton and Manchester Railway Mr. Binney dis-
covered Sigillarias standing erect, and evidently connected
with Stigmarias which extended 20 feet or more.* Stigmaria
is regarded by Schimper as roots, not of Sigillaria only, but
of Knorria longifolia (one of the Lepidodendreas). The base
of the stem of this species of Knorria is Ancestrophyllum, and
the upper part is Didymophyllum Schottini of Goeppert. Pro-
fessor King and others suppose that the Fem-like frond called
Neuropteris is connected with Sigillaria, but this is a mere
conjecture, set aside by the discovery of leaves attached to a
species allied to Sigillaria elegans, which establishes that the
long linear leaves described under the name Cyperites are the
foliage of this genus. Goldenberg has figured the fructifica-
tion, which consists of small sporangia like those of Fleming-

* The imbedding of plants in an erect state in strata is similar to
what was noticed at the present day by Gardner in Brazil, where
stems of recent Coco-nut Palms were seen covered with sand to the
depth of 50 feet.

FLORA OF THE CARBONIFEROUS EPOCH.

49

ites, borne on the basis of but slightly modified leaves. This
establishes the opinion that Sigillaria was an acrogenous plant
belonging to Lycopodiacea3. Brongniart reckons it as repre-
senting an extinct form of Gymnospeniis, and King, having
erroneously associated the Cyclopteris with it, places it between
the Ferns and Cycadace^e. Mr. Carruthers informs me that
he has examined the stem of a true fluted Sigillaria, with the
tissues preserved, and that these agree with the structure of
Lepidodendron, a position in which he had already placed it
from the structure of its fruit.

Lepidodendron (Figs. 40 to 44) is another genus of the
coal-measures which differs from those of the present day

Fig. 41.

(Plate IV. Fig. 3). Lepidodendrons, or fossil Lycopodiacese,
had spikes of fructification comparable in size to the cones
of firs and cedars, and containing very large sporangia, even
larger than those of Isoetes, to which they approach in form
and structure. Schimper, in 1870, enumerates 56 species of
Lepidodendron, all arborescent and carboniferous. The stem
of a Lepidodendron is from 20 to 45 feet high, marked outside

Figs. 40 to 44 exhibit the stems and fructification of Lepidoden
dron. Fig. 40. Bifurcating stem of Lepidodendron ohovatum (elegans)^
showing the scale-like scars, and the narrow-pointed leaves, resembling
those of Lycopodium, but much larger. Fig. 41. Stem oi Leindo-
dendron crenatmn, with the scars of its leaves.

E

50

PAL^ONTOLOGICAL BOTANY.

by peculiar scale-like scars (Fig. 41), hence the name of the
plant (XcTTtg, a scale, and hivZpov, a tree). Although the scars
on Lepidodendron are usually flattened, yet in some species
they occupy the faces of diamond-shaped projections, elevated
one-sixth of an inch or more above the surface of the stem, and
separated from each other by deep furrows; — the surface
bearing the leaf being perforated by a tubular cavity, through
which the bundle of vessels that diverged from the vascular

Fig. 42. Fig. 43.

axis of the stem to the leaf passed out. The linear or lanceo-
late leaves are arranged in the same way as those of Lycopo-
diums or of Conifera3, and the branches fork like the former.
The internal structure of the stem is the same as that of Sigil-
laria. The fruit of Lepidodendron and allied genera is seen
in Lepidostrobus and Triplosporites (Figs. 42, 43 ; Plate III,

Fig. 42. Fructification of Lepidodendron, showing its cone-like form
and spiral arrangement of scales. It is called Lepidostrobus Dahadianus
by Schimper, but it is probably Triplosporites.

Fig. 43. Longitudinal section of the fructification, showing central
axis and scales carrying sporangia. The upper sporangium contains
microspores, the lower macrospores ; hence it has the character of
Triplosporites.

FLORA OF THE CARBONIFEROUS EPOCH. 51

Fig. 10). Carmthers, iii his lecture to the Royal Institution,

WOSM-TH DEL

Fig. 44.

Ill woodcut 44 are represented the fruits of Selaginella (one of
the Lycopodiums of the present day), Lepidostrobus, Triplosporites,
and Flemingites. Fig. 1. Selagmella spinulosa, A. Braun [Lycopo-
dium selaginoides, Linn.) 2. Scale and sporangium from the upper
portion of the cone. 3. Antheridian microspores from the same.
4. Macrospore. 5. Scale and sporangium from the lower part of
the cone, containing macrospores. 6. Lepidostrobus ornatus, Hooker.
7. Three scales and sporangia of ditto, 8. Microspores from the
sporangia of the upper part of the cone of Triplosporites Broivnii,
Brongn. 9. Macrospore from the sporangia of the lower part (drawn
from Brongniart's description and measurements). 10. Scales and
sporangia of a cone of Flemingites. *

* For woodcuts 44, 47, and 48, I am mdebted to Dr. H. Bence

52 PAL^ONTOLOGICAL BOTANY.

in describing the forms of Lcpidostrobus, says — " The fRiit is a
cone composed of imbricated scales arranged spirally on the axis
like the true leaves, and bearing the sjDorangia on their hori-
zontal pedicels. Three different forms of fruit belong to this
genus, or it should perhaps rather be called group of plants.
The first of these is the cone named by Robert Brown Triplo-
sporites (Figs. 42, 43), and described by him from an exquisitely
preserved specimen of an upper portion, in which the parts are
exhibited as clearly in the petrified condition as if they belonged
to a fresh and living plant. The large sporangia have a double
wall, the outer composed of a compact layer of oblong cells
placed endwise, or with the long diameter i:)erpendicular to
the surface ; the inner is a delicate cellular membrane. The
sporangium is filled with a great number of very small spores,
each composed of three roundish bodies or sporules. Recently
Bronguiart and Schimper have described a complete specimen
of this fruit, in which the minute triple spores are confined
to the sporangia of the upper and middle part of the cone,
but the lower portion, which was wanting in Brown's speci-
men, bears sporangia filled with simple spherical spores ten
or twelve times larger than the others (woodcut 44, 9).

" The structure of another form of cone (Lepidostrobus)
has been expounded by Dr. Hooker. The arrangement of
the different parts comprising it is precisely similar to what
occurs in Triplosporites ; but the sporangia are filled with the
minute triple spores throughout the whole cone (woodcut 44,
6 and 8).

'' The third form of cone, described by me under the name
Flemingites, differs from the other two in having a large num-
ber of small sporangia supported on the surface of each

Jones, who has kindly placed them at my disposal. They were used
to illustrate Mr. Carruthers' remarks on the Cryptogamic forests of
the Coal period, published in the Journal of the Royal Institution of
Great Britain, April 16, 18G9. Mr. Carruthers' observations are
given in the text.

FLORA OF THE CARBONIFEROUS EPOCH. 53

scale; and it agrees with Lepidostrobus in the sporangia
containing only small spores (woodcut 44, 10).

^' In comparing these fossils with the living club-mosses, one
is struck with the singular agreement in the organisation of
plants so far removed in time, and so different in size, as the
recent humble club-mosses and the palaeozoic tree Lepidoden-
drons. The fruit of Triplosporites, like that of Selaginella
(woodcut 44, 1), contains large and small spores, the micro-
spores being found in both genera on the middle and upper
scales of the cone, and the macrospores on those of the
lower portion (Fig. 43).

" On the other hand, the fruits of Lepidostrobus and
Flemingites agree with that of Lycopodiiim in having only
microsj)ores. The size of the two kinds of spores also singu-
larly agrees in the t^vo groups. This is of some importance,
for among the recent vascular Cryptogams there is a remark-
able uniformity in the size of the spores in the members
of the different groups, even when there is a great variety in
the size of the plants. Thus the spore of our humble wall-
rue is as large as that of the giant Alsophila of tropical
regions. So also the spores of Equisetum and Calamites
agree in size, as may be seen in woodcut 47, Figs. 3, 4, and 9,
where the spores of the two genera are magnified to the same
extent. And a similar comparison of the macrospore and
microspore of Triplosporites with those of Selaginella, and of
the microspore of Lepidostrobus with that of Lycopodium,
exhibits a similar agreement. .This is made apparent by
the drawings in woodcut 44 of the two kinds of spores of
Selaginella, 3 and 4, with those of Triplosporites, 8 and 9,
which are drawn to the same scale."

The genus Sigillaria, as we have already said, has, according
to the observation of Hooker, small sporangia exactly agreeing
in size and form with those of Flemingites. Most probably
the contents of these small sporangia were the same in both
genera, so that Sigillaria W' ould be placed with Flemingites

54 PAL^ONTOLOGICAL BOTANY.

and Lepiclostrobus as arborescent Lycopodiacea) having their
affinities with Ly cop odium, as they have all microspores only
in their fructification.

The scales upon the Lepidodendron stems, as well as those
in the cones, are arranged in a spiral manner, in the same
way as plants of the present day. Professor Alexander
Dickson has examined the phyllotaxis of Lepidodendrons, and
gives the following results of his observations (Trans. Bot.
Soc. Edin. xi. 145). The fossil remains of Lepidodendrons
are often so compressed that it is difficult, or even impossible,
to trace the secondary spirals round the circumference of the
stem. In those cases, however, where there is comparatively
little compression, i.e. where the stem is more or less cylin-
drical, the determination of the phyllotaxis is easy. Of such
stems he has examined fifteen specimens, which may be
classed according to the series of spirals to which the leaf-
arrangement belongs : —

A. Ordinary series, i i, f , f, -^^ etc.
(a.) Single spirals (D turning to the right, S to the left).
(1.) Lepidodendron (Possil Ironstone series). Stem about |-

of an inch in diameter. Secondary spirals 8 D, 1 3 S, 2 1 D.

Divergence = ^|- (or possibly -f^).
(2.) Lepidodendron (Knightswood, near Glasgow, Mr. J. Young).

Stem about IJ inch in diameter. Secondary spirals 13 D,

21 S, 34 D. Divergence = fi.
(3.) Lepidodendron (Possil Sandstone series). Trunk about

2 feet long, with an average diameter of 20 inches. Steepest

secondary spirals 55 S. 89 D. Divergence == y^^j^^^.
(b.) Conjugate spirals.*
(4.) Lepidostrohus ornatus (Bathgate coal-field). About | of

an inch in diameter. Secondary spirals 10 D, 16 S, 26 D,

42 S. Divergence = ~~^ (Bijugate arrangement).

* Conjugate spirals result from u-horls of usually 2, 3, 5, 8, etc.,
leaves arranged so as to give 2, 3, 5, 8, etc., parallel spirals, each
with an angular divergence equal to ^, ^, ~, ^, etc., of one of the
fractions expressing the divergence in an arrangement of alternate
leaves.

FLORA OF THE CARBONIFEROUS EPOCH. 55

(5.) Lepidostrobus (Plean, Stirlingshire, Mr. Mackenzie).
About i an inch in diameter. Secondary spirals 9 S, 1 5 D,
24 S, 39 D. Divergence = gi^ (Trijngate arrangement).

(6.) Knorria taxina (from collection of Dr. Eankin, Carluke).
Somewhat compressed, 2-2^ inches'^ in diameter. Second-
ary spirals 15 D, 24 S. Divergence - j^^ (Trijugate ar-
rangement).

(7.) Lejjidodendron (from Dr. Eankin's collection). About 1^^
inch in diameter. Secondary spirals 10 D, 15 S, 25 D, 40
S. Divergence = -^. (Quinquejugate arrangement).

(8.) Lepidodendron (Dowanhill, Glasgow, Fossil Sandstone
series). Trunk about 1 foot long, and 1 foot in diameter.
The upper portion exhibits secondary spirals 35 D, 56 S,
91 D; thus indicating a 7 -jugate arrangement, with diver-
gence - .:j-^. The arrangement on the middle and lower
portion is indistinct and confused ; so much so as to render
any determination of the arrangement doubtful.
±5. beries, g^, -j-, -fj yt' ^^^'

(9.) Lepidodendron (Messrs Merry and Cunningham's Clayband
Iron-Pit, Carluke). Stem 2 inches in diameter. Second-
ary spirals 18 S, 29 D, 47 S. Divergence = -fi-
Kj. beries, -^, g-, -g-, y^, etc.

(10.) Lepidodendron (R. B. Garden, Edinburgh, Museum).
Stem somewhat flattened, 1-1 -| inch in diameter. Second-
ary spirals 9 D, 14 S, 23 D, 37 S. Divergence - if .

(11.) Lepidodendron (Redhaugh, near Edinburgh, Mr. Peach).
Stem somewhat flattened, f to ^ inch in diameter.
Secondary spirals 9 S, 14 D, 23 S, 37 D. Divergence =

1 .3
60*

D Spripc; 1 i _2_ _3_ _5_ pff.
(12.) Knorria taxina (Stockbriggs, Lesmahagow, — Hunterian
Museum). About 1 inch in diameter. The specimen con-
sists of a main stem and one of the branches into which it
has forked. On the main stem the secondary spirals are
6 D, 11 S, 17 D. Divergence = 2V (series, i I, yV? _^^
-/g-, etc.) — On the branch the secondary spirals are 8 S,
1 3 D. Divergence = 2^ (ordinary series, i, -|-, f , f , etc.)

'^ By inadvertence, the diameter is stated in my Class-book as
4-5 inches.

56 PALiEONTOLOGICAL BOTANY.

F. Spn'pS -1 -2 -3- _5_ _8_ 1_3 2J. pfp
J^. KOt;ilt;&, 2) 5J 71 125 19J 31? 5 0J^^^'

(13.) Leiy'idodendron (from Dr. Rankin's collection). About |-
inch in diameter. Secondary spirals 12 D, 19 S, 31 D.
Divergence = |-^.
F Sprips -1 -3_ _iL_ __7_ ii jLA etc

(14.) Lepidodendron elegans (Possil Ironstone). About Ij

inch in diameter. Secondary spirals 10 S, 13 D, 23 S,

36 D. Divergence = ^.
(15.) Lejndodendron (Possil Ironstone). About 2 J inches

in diameter. Secondary spirals 23 S, 36 D, 59 S, 95 D.

Divergence = yYt-

From the above it is evident that the phyllotaxis of
Lepidodendron is extremely variable, as much so perhaps as
that of those most variable plants, in this respect, the Cacti.
It is also clear that what has been enmiciated by Professor
Haughton (Manual of Geology, Lond. 1866, pp. 243, 245)
as the law according to which the leaves of paleozoic plants
were arranged — viz. that of alternate whorls — does not apply
to these ancient Lycopods. Lepidodendron aculeatum is
noted by Naumann as exhibiting an /y arrangement. (Pog-
gendorff, Annalen, 1842, p. 5.) Professor Alexander Braun
(Nov. Acta Ac. C. L. C. xv. I, pp. 558-9), speaking of the
excessive deviation from ordinary arrangements in Equise-
tacege (including Calamites), compares them in this respect
with Lycopodiacea3 (including Lepidodendron), saying that
in these two families " the utmost limits of the domain of all
leaf-arrangement appears to be attained."

Lepidophyllum is certainly leaves of Lepidodendron, the
different Lepidophylla belonging to different species of the
genus. The slender terminal branches are noticed under the
name of Lycopodites. In coal from Fordel Mr. Daw has
detected innumerable bodies (Plate III. Figs. I, 2, 3) which
have been shown to be sporangia. (Balfour, Trans. Roy.
Soc. Ed. xxi. 187.) On their under surface Mr. Carruthers
has observed a triradiate ridge (Plate III. Fig. 4). (Geological
Magazine, 1865, vol. ii. p. 140.) These sporangia have been

FLORA OF THE CARBONIFEROUS EPOCH.

57

found connected with the cone-like fructification called
Flemingites, and resembling Lycopodium (woodcut 44, Fig.
4). Many forms of fossil plants, such as Halonia, Lepidophloios,
Kuorria, and Ulodendron, belong to the Lepidodendron group.
Knorria is said to be the internal cast of a Lepidodendron.

Ulodendron minus and U. Taylori (Plate III. Fig. 11),
found in ferruginous shale in the Water of Leith, near
Colinton, exhibit beautiful sculptured scars, ranged recti-
linearly along the stem. The surface is covered with small,
sharply relieved obovate scales, most of them furnished with
an apparent midrib, and with their edges slightly turned up.
The circular or oval scars of this genus are probably impres-
sions made by a rectilinear range of aerial roots placed on
either side. When decorticated, the stem is mottled over
with minute dottings arranged in a
quincuncial manner, and its oval scars
are devoid of the ordinary sculpturings.
Bothrodendron is a decorticated con-
dition of Ulodendron.

Calamites (fcaXa/xo?, a reed) is a
reed-like fossil, having a sub-cylindri-
cal jointed stem (Fig. 45, a and h ;
Fig. 46; Plate IV. Fig. 4). The stem is
often crushed and flattened, and was originally hollow. Cala-
mites is thus defined by Grand d'Eury (Ann. Nat. Hist. ser. 4,
vol. iv. p. 124) : — Stem articulated, fistular, and
septate; outer part comparatively thin, formed of
three concentric zones — 1, an exterior cortical layer
now converted into coal ; 2, a thin subjacent zone
of vascular tissue, now invariably destroyed ; 3, a
sort of inner lining epidermis, which is carbonified. Cortical
envelope marked interiorly with regular flutings, interrupted
and alternate at the articulations. Inner epidermis smooth,

Fi.cr. 45 a.

Fiir. 45 6.

Fig. 45. a, Calamites Suckovii, composed of jointed striated frag-
ments having a bark. Fig. 45. b, Septum or phragma of a Calamite.

58

PAL.5]0NT0L0GICAL B0TA:NT.

or scarcely striated. Vascular cylinder thin; outer surface
of bark more fully fluted and articulated than the inner surface.
Carruthers gives the following description of the structure
of a species of Calamite which he examined : — The stem was
composed of a central medulla, which disappeared with the
growth of the plant, surrounded by a woody cylinder, com-
posed entirely of scalariform vessels, and a thin cortical layer.
The medulla penetrated the woody cylinder by a series of
regular wedges, which were continued, as delicate laminas of

Fig. 46.

one or two cells in thickness, to the cortical layer. The cells
of those lamince were not muriform ; their longest diameter
was in the direction of the axis. The wedges were continuous,
and parallel between each node. As the axial appendages
were produced in whorls, the only interference with the regu-
larity of the tissues was by the passing out through the stem
at the nodes of the vascular bundles which supplied these ap-
pendages. As the leaves of each whorl were (with one or

Fig. 46. Vertical stems of fossil trees, Calamites chiefly, found in
the coal-measures of Treuil, near Saint Etienne.

FLORA OF THE CARBONIFEROUS EPOCH. 59

two exceptions) opposite to the interspaces of the whorls above
and below, there was also at each node a re-arrangement of
the wedges of vascular and cellular tissues.

Schimper considers Calamites as having an analogy with
Equisetum in its fructification. He looks on them as fossil
Equisetacea3. Annularia and Sphenophyllum are considered
as establishing a passage from the Equisetaceas to the Lycopo-
diacege. Some gigantic fossil Equiseta had a diameter of
nearly 5 inches, and a height of 30 or more feet. The
branches, which adorned the higher part of them in the
form of a crown, are simple, and have at their extremity a
spike of the size of a pigeon's egg, and organised exactly like
the spikes of living Equiseta. The subterranean rhizomes are
well developed, and gave origin, like many Equiseta, to
tubercles which had the fonn and size of a hen's egg.

The characters of Equisetum of the present day and
Calamites, are exhibited in woodcut 47. They show a marked
resemblance in the fructification. (See also page 31.)

Plants of Calamites have been seen erect by Mr. Binney,
and he has detennined that what were called leaves or branches
by some are in reality roots. Mr. Binney gives a full descrip-
tion of various Calamites, under the name of Calamodendron
commune, in his Memoir published by the Pal^ontographical
Society, 1868. There are between 50 and 60 species recorded.*

In Spitzbergen, in rocks of the Carboniferous epoch, there
have been found Calamites, Sigillaria, Lepidodendron, and
ferns, apparently the same as those found in the Carboniferous
epoch in Europe — Calamites radiatus, Lepidodendron Velthei-
mianum, Sigillaria distans, Stigmaria ficoides. Some species
— Sigillaria INIalmgreni, Lepidodendron Carneggiannum, and
L. Wilkianum — seem to be peculiar to Bear Island.

According to Carruthers the Equisetacea? are represented
in Britain by the two genera Calamites found in primary beds,

* See Eemarks on the Structure of Calamites by W. C. William-
son, Philos. Trans., 161, p. 477.

GO

PAL^ONTOLOGICAL BOTANY.

and Equisetum found in secondary rocks and living at the
present day. Tlie difference in the structure of their fruits

Fig. 47.

is shown in woodcut 47. The fruit of Calamites, called
Volkmannia Binneyi (woodcut 47, 7), is a small slender
cone composed of alternating whorls of imbricate scales,
twelve in each verticil. The scales completely conceal

Fig. 47. Fruits of Equisetum and Calamites. 1. Equisetum arvense,
L. 2. Portion of sporangium wall. 3, 4. Spores, with the elaters free.
5. Longitudinal section of the part of one side of cone. 6. Trans-
verse section of cone. 7. Calamites (Volkmannia) Binneyi, Carr.,
magnified three times. 8. Portion of the sporangium wall. 9. Two
spores. 10. Longitudinal section of the part of one side of cone.,
11. Transverse section of cone.

FLORA OF THE CARBONIFEROUS EPOCH. 61

the leaves connected with the fructification. The fmit-
bearing leaves are stalked, peltate, and are arranged in
whorls of 6. There are four sporangia borne on the under-
surface of the peltate leaves. These spore- cases have cellular
parietes, and in their interior there is a deposit of cellulose
in the fonn of short truncate processes not unlike imperfect
spirals. The spores are spherical, and appear to have thread-
like processes proceeding from them, similar to elaters. The
fruit-cone bears a marked resemblance to the fruit of Equi-
setum in its fiiiit-bearing leaves, sporangia, spores, and
elaters (see Figs. 18, 19, 20, 21). In the modem plant all
the leaves of the cone are fructiferous, while in the fossil
plant some are fruit-bearing, and others are like the ordinary
leaves of the plant. It is thought that the fossil may be
reckoned as having a somewhat higher position than that pos-
sessed by the living genus.

The different forms of foliage called Asterophyllites,
Sphenophyllum, and Annularia, belong to the one genus
Calamites, but they may form, perhaps, well-characterised
sections when their fruits are better known. In woodcut 48
representations are given of the foliage and fruit of varieties
of Calamites. In 1 and 2 we see the simplest form called
Asterophyllites. The leaves are linear and slender, with a
single rib. The form called Annularia (3 and 4) differs chiefly
in having a larger amount of cellular tissue spread out on
either side of the midrib. This form has a different aspect
in a fossil state from the other, from its whorls of numerous
broad leaves spread out on the surface of deposition, while
the acicular leaves of Asterophyllites have penetrated the soft
mud, and are generally preserved in the position they origin-
ally occupied in reference to the supporting branch. The
third form (5 and 6) is called Sphenophyllum, and consists of
whorls of wedge-shaped leaves, with one or more bifurcating
veins. They occur like those of Annularia, spread out on the
surface of the shale.

62

PAL^ONTOLOGICAL BOTANY.

True Exogenous trees exist in the coal-fields both of Enir-
land and Scotland, as at Lennel Braes and Allan Bank, in
Berwickshire ; High-Heworth, Fellon, Gateshead, and Wide-
open, near Newcastle-upon-Tyne ; and in quarries to the west of

Fig. 48.

Durham ; also in Craigleith quarry, near Edinburgh, and in the
quany at Granton, now under water. In the latter localities
they lay diagonally athwart the sandstone strata, at an angle of
about 30°, with the thicker and heavier part of their trunks
below, like snags in the Mississippi. From their direction we
infer that they have been drifted by a stream which has flowed

Fig. 48. Foliage and fruits of Calamites. 1 and 2. Asterophyl-
lites; 3 and 4. Annularia; 5 and 6. Sphenophyllum.

FLORA OF THE CARBONIFEROUS EPOCH.

63

from nearly north-east to south-west. At Granton, one of
the specimens exhibited roots. In other places the specimens
are portions of stems^ one of them 6 feet in diameter by 61
feet in length, and another 4 feet in diameter by 70 feet in
length. These Exogenous trees are Gymnosperms, having
woody tissue like that of Conifer^e. We see under the
microscope punctated woody tissue, the rows of disks being
usually two, three, or more, and alternating. They seem to
be allied in these respects to Araucaria and Eutassa (Fig.
61, p. 74) of the present flora. Araucarioxylon or Pinites
Withami (Fig. 49) is one of the species found in Craigleith

Ficr. 49.

Fig. 50.

quarry ; the concentric layers of the wood are obsolete ; there
are 2, 3, or 4 rows of disks on the wood, and 2-4 rows of
small cells in the medullary rays. Along Avith it there have
also been found Dadoxylon medullare, with inconspicuous
zones, 2, 3, and 4 rows of disks, and 2-5 series of rows of cells
in the rays. Pissadendron antiquum (Pitus antiqua) having

Fig. 49. Araucarioxylon Withami, Krauss {Pinites Withami), from
the Coal-measures, Craigleith, near Edinburgh, showing pleurenchyma
with disks, and medullary rays. An excellent specimen of a stem of
this pine may be seen in the Edinburgh Royal Botanic Garden.

Fig. 50. Trigonocarjmm olivmforme, an ovate, acuminate, three-
ribbed, and striated fruit or seed, which some suppose to be a
sporangium of a Lepidodendron, others refer it to Cycadacese.
Hooker refers it to Coniferse like Salisburia.

64 PAL^ONTOLOGICAL BOTANY.

4-5 series of cells in the medullary rays, and P. prima3vum
(Pitus primtBva), with 10-15 series of cells in the medullary
rays, occur at Tweedmill and Lennel Braes in Berwickshire ;
Pence Withami (Fig. 1, p. 3) at Hilltop, near Durham, and
at Craigleith. Sternbergia is considered by Williamson as a
Dadoxylon, with a discoid pith like that seen now-a-days in
the Walnut, Jasmine, and Cecropia peltata, as well as in some
species of Euphorbia.* Sternbergia approximata is named by
him Dadoxylon approximatum. Hooker believes from the
structure of Trigonocarpum (Fig. 50) that it is a coniferous
fruit nearly allied to Salisburia (Trans. Roy. Soc. 1854).
Several species of Trigonocarpum occur in the Carboni-
ferous rocks, such as T. oliv^eforme from Bolton (Plate II.
Fig. 5), and T. sulcatum from Wardie, near Edinburgh (Plate
II. Fig. 6). Noeggerathia and a few other plants, such as
Flabellaria and Artisia, are referred by Brongniart to Cyca-
dacege. Flabellaria borassifolia, according to Peach, has
leaves like Yucca. Noeggerathia has pinnate leaves, cunei-
form leaflets, sometimes fan-shaped ; the veins arise from the
base of the leaflets, are equal in size, and either remain simple
or bifurcate, the nervation (venation) being similar to that of
some Zamias.

The fossils of this period, referred to as Antholithes,t have
just been shown by Mr. Carruthers to be the inflorescence of
Cardiocarpum (Geol. Mag. Feb. 1872), and he proposes to set
aside the former name, confining it to the tertiary fossils to
which it was originally given by Brongniart, and to use the
latter name. The main axis of the inflorescence is simple,
stout, and marked externally with interrupted ridges. The

* Williamson on the Structure and Affinities of Sternbergise, in
Manch. Lit. and Phil. Soc. Mem. ix. Dawson on Sternbergia, in
Edin. New Phil. Journ., new series, vii. 140.

t See Notice of A7itholithes Pitcairnice, by 0. W. Peach, in Bot. Soc.
Trans. Edin. vol. xi.

FLORA OF THE CARBONIFEROUS EPOCH. 65

axis bears in a distichous manner sub-opposite or alternate
bracts of a linear-lanceolate form and with decurrent bases.
In the axils of the bracts were developed flower-like leaf-
bearing buds, and from them proceeded three or four linear
pedicels, which terminated upwards in a somewhat enlarged
trumpet-shaped apex. To this enlarged articulating surface
was attached the fruit, to which has been given the generic
name Cardiocarpum'''' (Fig. 51). The place of attachment is
indicated by the short straight line which separates the cordate
lobes at the base of the fruit. The fruit is flattish, broadly
ovatC; with a cordate base and sub-acute apex. It consists of

Fig. 51. Fig. 52.

an outer pericarp, inclosing an ovate-acute seed. That the
pericarp was of some thickness, and formed probably a sub-
indurated rind, is shown by a specimen preserved in the
round, and figured (Fig. 53 a). The pericarp is open at the
apex; and the elongated tubular apex of the spermodei-m
passes up to this opening. The seed forms a distinct swelling
in the centre of the fruit, and a slight ridge passes up the
middle to the base of the apical opening.

These fossils are believed to be an extinct form of Gymno-
sperms. Two species have been described, of both of which

Fig. 51. Cardiocaiyum Lindleyi, Carr. Fig. 52. Do., Coal-measures,
Falkirk.

* See Professor Duns ou the associatiou of Cardiocarpum with
Sphenopteris. Proc. R.S.E., April 1, 1872.

F

66 -

PAL^ONTOLOGICAL BOTANY.

we are able to give figures. The first figure is from the spe-
cimens collected by Mr. Peach at Falkirk. It is Cardiocarpum
Lindleyi (Figs. 51, 52); it has a primary axis with sub-
opposite axillary axes, bearing four to six lanceolate leaves
and three or four pedicels. Primary bracts short and arcuate.
Fruit ovate-cordate, with an acute bifid apex, and a ridge
passing up the middle of the fruit.

The second species is Cardiocarpum anomalum (Fig. 53)

from Coalbrookdale ;
it has a primary axis
with alternate or sub-
opposite axillary axes,
slender and elongated,
bearing many linear
leaves, and several
slender pedicels; pri-
mary bracts long, slen-
der, and straight ;
Fig. 53. fruits small, margined.

The somewhat magnified separate fruit {a) shows the thickness
of the pericarp and the enclosed seed.

In the bituminous shale at Granton, near Edinburgh, Dr.
Robert Paterson discovered in 1840 a peculiar fossil plant,
which he called Pothocites Grantoni (Fig. 54, a). It is figured
in the Transactions of the Edinburgh Botanical Society, vol. i.
March 1840. It is a spike covered by parallel rows of flowers
(Fig. 54, 5), each apparently *vith a 4-cleft calyx (Fig. 54, c).
It was supposed to be allied to Potamogeton or Pothos, more
probably to the latter. In that case it must be referred to the
natural order Arace«. The original specimen is deposited in
the museum at the Royal Botanic Garden, Edinburgh.

Our knowledge of the real state of the vegetation of the

Fig. 53. Cardiocarpum anomalum (Carr.), natural size : with sepa-
rate fruit (a), twice natural size — Coal-measures, Coalbrookdale.

FLORA OF THE CARBONIFEROUS EPOCH.

67

Ficr. 54.

earth when coal was formed must be very limited, when we
reflect how seldom the fructification of coniferous trees has
been met with in the coal-measures.
A very doubtful fragment, supposed
to be a cone, is given in Lindley and
Hutton's work, under the title of Pinus
anthracina ; but it is believed by Car-
ruthers to be a fragment of a Lepido-
dendroid branch. Lyell never saw a
fossil fir-cone of the Carboniferous
epoch, either in the rocks or museums
of North America or Europe. Bunbury
never heard of any other example than
that noticed by Lindley and Hutton.
Principal Dawson is disposed to think
that the suberin of cork, of epidermis in
general, and of spore-cases in particular, is a substance so rich
in carbon that it is very near to coal, and so indestructible and
impermeable to water, that it contributes more largely than any-
thing else to the mineral. Sir Charles Lyell remarks — "To pre-
vent ourselves, therefore, from hazarding false generalisations,
we must ever bear in mind the extreme scantiness of our present
information respecting the flora of that peculiar class of sta-
tions to which, in the Palaeozoic era, the coal-measures pro-
bably belonged. I have stated elsewhere my conviction that
the plants which produced coal were not drifted from a dis-
tance, but nearly all of them grew on the spot where they
became fossil. They constituted the vegetation of low regions,
chiefly the deltas of large rivers, slightly elevated above the
level of the sea, and liable to be submerged beneath the
waters of an estuary or sea by the subsidence of the ground
to the amount of a few feet. That the areas where the car-

Fig. 54. PotJiocites Grantoni, Paterson. a, Spike natural size ;
6, Portion of spike magnified ; c, Perianth, 4-cleft, magnified.

68 PAL^ONTOLOGICAL BOTANY.

boniferous deposits accumulated were low, is proved not only
by the occasional association of marine remains, but by the
enomious thickness of strata of shale and sandstone to which the
seams of coal are subordinate. The coal-measures are often
thousands of feet, and sometimes two or three miles, in yerti-
cal thickness, and they imply that for an indefinite number of
ages a great body of water flowed continuously in one direc-
tion, carrying doTvn towards a given area the detritus of a
large hydrographical basin, draining some large islands or
continents, on the margins of which the forests of the coal
period grew. If this view be correct, we can know little or
nothing of the upland flora of the same era, still less of the
contemporaneous plants of the mountainous or alpine regions.
If so, this fact may go far to account for the apparent mono-
tony of the vegetation, although its uniform character may
doubtless be in part oAving to a greater uniformity of climate
then prevailing throughout the globe. Mr. Bunbury has suc-
cessfully pointed out that the peculiarity of the carboniferous
climate consisted more in the humidity of the atmosphere and
the absence of cold, or rather the equable temperature pre-
served in the different seasons of the year, than in its tropical
heat ; but we must still presume that colder climates existed
at higher elevations above the sea."

The plants of the coal-measures are evidently terrestrial
plants. Brongniart agrees with Lyell in thinking that the
layers of coal have in general accumulated in the situation
where the plants forming them grew. The remains of these
plants covered the soil in the same way as layers of peat, or
the vegetable mould of great forests. In a few instances,
however, the plants may have been transported from a dis-
tance, and drifted into basins. Phillips is disposed to think
that this was the general mode of formation of coal-basins.
He is led to this conclusion by observing the fragmentary
state of the stems and branches, the general absence of roots,

FLORA OF THE CARBONIFEROUS EPOCH. 69

and the scattered condition of all the separable organs. Those
who support the drift theory, look on the coal plants as having
been swept from the land on which they grew by watery
currents at different times, and deposited in basins and large
sea-estuaries, and sometimes in lakes. The snags in the
Mississippi, the St. Lawrence, and other large rivers, are given
as instances of a similar drifting process.

The vegetation of the coal epoch seems to resemble most
that of islands in the midst of vast oceans, and the prevalence
of ferns indicates a climate similar to that of New Zealand in
the present day. In speaking of the island vegetation of the
coal epoch, Professor Ansted remarks (Ancient World, p.
88) — "The whole of the interior of the islands may have
been clothed with thick forests, the dark verdure of which
would only be interrupted by the bright green of the swamps
in the hollows, or the brown tint of the ferns covering some
districts near the coasts. The forests may have been formed
by a mixture of several different trees. We would see then,
for instance, the lofty and widely-spreading Lepidodendron,
its delicate feathery fronds clothing, in rich luxuriance,
branches and stems, which are built up, like the trunk of
the tree-fern, by successive leafstalks that have one after
another dropped away, giving by their decay additional
height to the stem, which might at length be mistaken for that
of a gigantic pine. There also should we find the Sigillaria, its
tapering and elegant form sustained on a large and firm basis —
enormous matted roots, almost , as large as the trunk itself,
being given off in every direction, and shooting out their
fibres far into the sand and clay in search of moistm-e. The
stem of this tree would appear like a fluted column, rising
simply and gracefully without branches to a great height, and
then spreading out a magnificent head of leaves like a noble
palm-tree. Other trees, more or less resembling palms, and
others like existing firs, also abounded, giving a richness and

70 PAL^ONTOLOGICAL BOTANY.

variety to the scene; wliile one gigantic species^ strikingly
resembling the Norfolk Island pine, might be seen towering
a hundred feet or more above the rest of the forest, and
exhibiting tier after tier of branches richly clothed with its
peculiar pointed spear-like leaves, the branches gradually
diminishing in size as they approach the apex of a lofty
pyramid of vegetation. Tree-ferns also in abundance might
there be recognised, occupying a prominent place in the
physiognomy of vegetation, and dotted at intervals over the
distant plains and valleys, the intermediate spaces being
clothed with low vegetation of more humble plants of the
same kind. These we may imagine exhibiting their rich
crests of numerous fronds, each many feet in length, and
produced in such quantity as to rival even the palm-trees in
beauty. Besides all these, other lofty trees of that day, whose
stems and branches are now called Calamites, existed chiefly
in the midst of swamps, and bore their singular branches and
leaves aloft with strange and monotonous unifomiity. All
these trees, and many others that might be associated with
them, were, perhaps, girt round with innumerable creepers
and parasitic plants, climbing to the topmost branches of the
most lofty amongst them, and relieving, in some measure, the
dark and gloomy character of the great masses of vegetation."
Hugh Miller remarks — "The sculpturesque character of
the nobly-fluted Sigillarias was shared by not a few of its
contemporaries. Ulodendrons, with their rectilinear rows of
circular scars, and their stems covered with leaf-like carvings,
rivalled in effect the ornately relieved torus of a Corinthian
column. Favularia, Halonia, many of the Calamites, and
all the Lepidodendrons, exhibited the most delicate sculp-
turing. In walking among the ruins of this ancient flora, the
pala3ontologist almost feels as if he had got among the broken
fragments of Italian jDalaces erected long years ago, when the
architecture of Rome was most ornate, and every moulding

FLORA OF THE PERMIAN EPOCH. 71

was roughened A^dth ornament ; and in attempting to call up
in fancy the old Carboniferous forests, he has to dwell on this
peculiar feature as one of the most prominent ; and to see in the
multitude of trunks darkened above by clouds of foliage that
rise upon him in the prospect, the slender columns of an older
Alhambra, roughened with arabesque tracery and exquisite
filigree work."

The nature of the vegetation during the Permian period,
which is associated with the Carboniferous, under the reign
of Acrogens, has been extensively illustrated by Goeppert.
Brongniart has enumerated the fossils in three different
localities, which he refers doubtfully to this period. 1.
The flora of the bituminous slates of Thuringia, composed
of Algsd, Ferns, and Conifera3. 2. Flora of the Pemiian sand-
stones of Russia, comprehending Ferns, Equisetacet^, Lycopo-
diacea?, and Nocggerathite. 3. Flora of the slaty schists of
Lod^ve, composed of Ferns, Asterophyllites, and Conifera?.
The genera of Ferns here met with are those found in the
Carboniferous epoch ; the Gymnosperms are chiefly species of
Walchia and Noeggerathia (the latter is supposed by Schimper
to be a Cycad) ; Lepidodendron elongatum, Calamites gigas,
and Annularia floribunda, are also species of this period.
Walchia is a conifer characteristic of the Permian epoch, of
which there are eight species described (Figs. 55 and 56). It
has a single seed to each scale of the cone, and two kinds of
leaves, the one short and imbricated, the other long and spread-
ing. Among the plants of the Pemiian formation Goeppert
enumerates the following :* — Equisetites contractus, Calamites
Suckowi, C. leioderma, Asterophyllites equisetiformis, A.
elatior, Huttonia truncata, H. equisetiformis, many species of
Psaronius, one of the filicoid plants, Hymenophyllites com-
planatus, Sphenopteris crassinervia, Sagenopteris ta^nigefolia,
Neuropteris imbricata, and many other species of these
* See Meyer's Palaeontographica, Cassel, 1864.

n

PAL^ONTOLOGICAL BOTANY.

genera; several species of Odontopteris, Callipteris, Cyclop-
teris, Dioonopteris, Cyatheites, Alethopteris, Noeggerathia,

Fig. 55.

Cordaites, Antliodiopsis, Dictyotlialamus, Calamodendron,
Artliropitys ; besides species of Sigillaria, Stigmaria^ and
Lepidodendron. Various fruits are also mentioned, under
the names of Rhabdocarpum, Cardiocarpum, Acanthocarpum,
Trigonocarpum, and Lepidostrobus.

FOSSIL FLORA OF THE SECONDARY OR
MESOZOIC PERIOD.

Reign of Gymnosperms.

The Gymnospermous plants of the present day are included
in two natural orders, Coniferas and Cycadaceas. Under
Conifers are enumerated the yarious species of Pine (Fig. 57),
Spruce (Fig. 58), Larch (Fig. 59), Cedar (Fig. 60), Eutassa,

Figs. 55 and 56. WaWiia jnniformis, Sternb., a common species
in the Permian rocks of Europe. Fig. 55. Plant with leaves and
fructification. Fig. 56. Fructification, natural size.

FLORA OF THE MESOZOIC PERIOD. 73

Araucaria (Fig. 61), Sequoia, Ciyptomeria, Taxodium, Cypress,

Fig. 58. Fig. 60.

Juniper (Fig. 70), Salisburia, Dacrydium, Yew (Fig. 71), etc.

Fig. 57. Pinus sylvestrisj Scotch Fir,

Fig. 58. Abies excelsa, common Sioruce Fir of northern Europe.
Fig. 59. Larix Eurojjcea, the Larch, indigenous on the Alps of
middle Europe.

Fig. 60. Gedrus Libani, Cedar of Lebanon.

74

PAL^ONTOLOGICAL BOTANY.

The ConiferaD of the present day are distinguished as
resinous trees or shrubs with punctated woody tissue (Figs.

Fg. 61.

Fisr. 65.

Fi?. 62.

Fig. 63.

Fig. 64.

62, 63, 64, 65), linear acerose or lanceolate parallel-veined
leaves, sometimes clustered, and having a membranous sheath

Fig. 61. Araucaria excelsa, csiWed siiso Altingia or Eutassa ov Eutacta
excelsa, Norfolk Island Pine.

Fig. 62. Woody tubes of fir, with single rows of discs.

Fig. 63. AVoody tubes of fir, with double rows of discs, which are
opposite to each other.

Fig. 64. Woody tubes of Araucaria excelsa, with double and triple
rows of discs, which are alternate.

Fig. 65. Longitudinal section of the stem of a Gymnosperm, show-
ing tubes of wood marked with punctations in one or more rows, and
a medullary ray composed of cells running across the pleurenchyma.

FLORA OF THE MESOZOIC PERIOD.

75

at the base (Fig. 66). Male flowers in deciduous catkins;
female flowers in cones (Figs. 67, 68). The seeds are con-

Fig. 66.

Fiir. 68.

Fit?. 69.

sidered by most botanists as being naked, ^. e, not contained
in a true pistil (Fig. 69). Some of the conifers have a succu-
lent cone, as the juniper (Fig. 70), and the yew (Figs. 71-
73) has a succulent mass covering a single naked seed (Fig.
73). The yew also has its pleurenchyma marked both with
punctations and spiral fibres. The arrangement of the punc-
tations in the Conifera? gives characters which enable us to
classify the woods into groups that have some relation to the

Fig. Q6. Linear leaves of Pinus Strohus, Weymouth Pine, in a
cluster of five, with scaly sheath at the base.

Fig. 67. Cone of Pinus sylvestris, Scotch Fir.

Fig. 68. Cone of Ciqjressus semijervirens, common Cypress.

Fig. 69. Scale, 5, of mature cone of Pinus sylvestris, with two naked
winged seeds, m m, at its base ; ch marks the chalaza, m the micropyle.

n

PAL^ONTOLOGICAL BOTANY.

genera established from the reproductive organs (see Figs.
62-65).

The natural order Cycadaceas is not so largely represented
at the present day as it was during the Mesozoic epoch.

Fig. 72.

Fig. 70.

Fig. 71.

Among the genera of the present day are Cycas (Fig. 74),
Zamia, Macrozamia, Encephalartos (Fig. 75), Dion, Stangeria,
etc. They are small palm-like trees or shrubs, with un-
branched stems, occasionally dichotomous, marked with leaf-
scars, and having large medullary rays along with pitted
woody tissue. The leaves are pinnate, except in Bowenia,
which has a bipinnate leaf. Males in cones. Females con-
sisting of naked ovules on the edges of altered leaves, or on
the inferior surface of the peltate apex of scales.*

Fig. 70. Fruiting branch of Juniperus communis, common Juniper,
with linear acerose leaves and succulent cones.

Fig. 71. Branch of Taxiis haccata, common Yew.

Fig. 72. Male flower of Yew, with bracts at the base.

Fig. 73. Fruit of Yew, consisting of a single naked seed partially
covered by a succulent receptacle.

* See fuller description of Coniferse and Cycadacese in Balfour's
Class Book of Botany, pp. 906-912.

FLORA OF THE TRIAS AND LIAS EPOCHS.

11

In tliis reign the Acrogenous species are less numerous;
the Gymnosperms ahuost equal them in number, and ordinarily
surpass them in frequency. There are two periods in this
reign, one in which Coniferae predominate, while Cyca-
dacese scarcely appear; and another in which the latter
family preponderates as regards the number of species,
and the frequency and variety of generic forms. Cyca-
dacea3 occupied a more important place in the ancient

ir:- .iiti

-,..-f^

Fig. 74.

than in the present yegetable world. They extend more or
less from the Trias formation up to the Tertiary. They are
rare in the Gres bigarr^ or lower strata of the Triassic system.
They attain their maximum in the Lias and Oolite, in each of
which upwards of 40 species have been enumerated, and they
disappear in the Tertiary formations. Schimper describes 13
genera of fossil Zamiee, and about 20 Cycadeae. He thinks
that Trigonocarpum (15 species), Rhabdocarpum (24 species),

Fig. 74. Cycas revoluta, one of the false Sago-plants found in Japan.
Fig. 75. Encephalartos {Zamia) pimgens, another starch-yielding
Cycad.

78

PAL^ONTOLOGICAL BOTANY.

Cardiocarpum (21 species), and Carpolitlies (9 species), are all
fruits of Cycade^e. Many supposed fossil Cycads are looked
upon by Carrutliers as Coniferte. Zamia macrocepliala, or
Zamites macrocephalus, or Zamiostrobus macrocephalus, is
called by him Pinites macrocephalus ; Zamia ovata, or Zamites
ovatus, or Zamiostrobus ovatus, is Pinites ovatus ; Zamia
Sussexiensis is Pinites Sussexiensis. Among other species of
Pinites noticed by Carruthers are Pinites oblongus, P. Ben-
stedi, P. Dunkeri, P. Mantellii, P. patens, P. Fittoni, P.
elongatus. It is important to notice that in an existing Cycad
called Stangeria paradoxa the veins of the pinnas rise from a
true midrib and fork, characters which render untenable the
distinction usually relied upon between the foliage of Ferns
and Cycads.

In Brongniart's Yosgesian period, the Gr^s bigarr^, or the
Red Sandstones and Conglomerates of the Triassic system,
there is a change in the flora. Sigillarias and Lepidodendrons

Fig. 76.

disappear, and in their place we meet with Gymnosperms,
belonging to the genera Voltzia, Haidingera, Zamites, Ctenis,

Fig. 76. Schizo7ieura heterojjhylla, one of the fossil Coniferoe of the
Triassic system.

FLORA OF THE TRIAS AND LIAS EPOCHS.

79

^thophyllum, and Schizoneura (Fig. 7Q). The genus Yoltzia
is confined to the Trias, and though a true conifer, it is not
easy to correlate it with any living form. It is apparently
Abietineous, having two seeds to each scale, but they are
placed on the dilated upper portion of the scale. The leaves
are of two kinds, the one broad and short, and the other at
the tops of the branches long and linear. Species of Neu-
ropteris, Pecopteris, and other acrogenous coal genera are
still found, along with species of Anomopteris and Crenia-
topteris — peculiar Fern-forms, which are not found in later
formations. Stems of aborescent Ferns are more frequent
than in the next period.

The Jurassic period of Brongniart embraces the Keupric
period or variegated marls of the Triassic system, the Liassic
epoch, the Oolitic and the Weal den. The flora of the
Keupric epoch differs from that of the Gr^s bigarre of the
Vosges. The Acrogens are changed as regards species, and
frequently in their genera.
Thus we have the genera
Camptopteris, Sageno-
pteris, and Equisetum.
Among Gymnospenns,
the genera Pterophyllum
and Taxodites occur.

In the Lias the essen-
tial characters of the flora
are the predominance of
Cycadacef©, in the fonn of
species of Cycadites, Oto-
zamites, Zamites (Fig. 77),
Ctenis, Pterophyllum (Fig. 78), and Nilssonia (Fig. 79),
Palasozamia (Fig. 80), and the existence among the Ferns of

Figs. 77 to 81. Cycadacese of the Jurassic epoch of Brongniart,
and of the Oohte. Fig. 77. Zamites, one of the fossil Cycadacese.

Fig. 77.

80

PAL^ONTOLOGICAL BOTANY.

Fig. 78. Fig. 79.

many genera with reticu-
lated venation, such as
Camptopteris and Thau-
matopteris, some of which
began to appear at the
Keupric epoch. Coni-
ferous genera, as Brachy-
phyllum (Fig. 81), Taxo-
dites, Palissya, and Pence,
are found. In the Lias near
Cromarty, Miller states
that he found a cone with
long bracts like those of
Pinus bracteata.

In the Oolitic epoch the

flora consists of numerous

Cycadacece and Conifer£e,

Fig. 80. some of them having pecu-

Fig. 78. Pterophyllum Pleiningerii, leaf of a fossil Cycad. Fig. 79.
Nilssoiiia compta {Pterophyllum comptum of Lindley and Hutton), from

FLORA OF THE OOLITIC EPOCH.

81

liar forms. Its distinctive characters are, the rarity of Ferns
with reticulated venation, which are so numerous in the Lias, the
frequency of the Cycadaceous genera Otozamites and Zamites,
which are most analogous to those now existing ; the occur-
rence of a remarkable group presenting very anomalous struc-
ture in their organs of reproduction, to which Carruthers has
given the name of Williamsonia ; and the diminution of Ctenis,
Pterophyllum, Pal^ozamia, and Nilssonia, genera far removed

Fig. 81.

from the living kinds ; and lastly, the greater frequency of
the coniferous genera, Brachyphyllum and Thuites, which
are much more rare in the Lias. In the Scottish Oolite at

the Oolite of Scarborough. Lower part of the piunatifid leaf, with
bkmt ahnost square divisions. There are numerous veins, slightly
varying in thickness ; while in Pterophyllum there are numerous veins
of equal thickness, in Cycadites there is a solitary vein forming a thick
midrib. Fig. 80. Pakuozamia ijectinata (Zamia xiectinata of Brong-
niart, and Lindley and Hutton), a pimiated leaf, with a slender rachis.
The pinnae are linear, somewhat obtuse, with slender equal ribs. It
is found in the Oolite of Stonesfield (Lindley and Hutton).

Fig. 81. Brachy2)hyllu7ii mammillare, a Coniferous plant of the
Oolitic system, Yorkshire.

Fig. 82. Equisetum columnare, a fossil opecies of the Oolite of
Yorkshire.

G

5Z5^

82

PAL^ONTOLOGICAL BOTANY.

Helmsdale, Miller detected about 60 species of plants, in-
cluding Cycadacege and Conifera3, with detached cones, and
Fern-forms resembling Scolopendrium. He also discovered a
species of Equisetum, and what he supposed to be a Calamite.
There is an absence of true coal-fields in the secondary
formations generally ; but in some of the Oolitic series, as in
the lower Oolite at Brora, in Sutherlandshire, and in the
north-east of Yorkshire, and the Kimmeridge clay of the
upper Oolite, near Weymouth, there are considerable deposits
of carbonaceous matter, sometimes forming seams of coal
which have been worked for economic purposes.* Some sup-
pose that the Brora coal was formed chiefly by Equisetum
columnare (Fig. 82). In the sandstones and shales of the

Yis. 84.

Fis, 83.

Fig. 85.

Oolitic series, especially in the lower Oolite of the north of
England, as at Whitby and Scarborough, as well as in Stones-
field slate, the Portland Crag of the middle, and the Port-
land beds of the upper Oolite, numerous fossil plants are
found. Pence Lindleyana is one of the Coniferge of the
lower Oolite. Beania (Plate H. Fig. 2) is a Cycadaceous

Fig. 83. Araucarites sphcerocarpus, Carr., found in the inferior
Oolite at Bruton, Somersetshire.

Fig. 84. Termination of a scale of Araucarites sjjhcerocarjms, Carr.

Fig. 85. Section of a scale of Araucarites sphcerocarpus, Carr.,
showing the size and pc^'tion of the seed.

* Coal in the Kimmeridge clay is probably of animal origin.

FLORA OF THE OOLITIC EPOCH. 83

fossil from tlie Oolite of Yorkshire (Carrutliers, Geol. Mag.
yi. 91). Araucarites sph^roearpus (Figs. 83, 84, 85) is found
in the inferior Oolite, and separate scales of Araucarian fruits
occur in the Oolitic shales of Yorkshire (Araucarites Phil-
lipsii, Plate II. Fig. 11), and in the " slate " at Stonesfield (A.
Brodiei, Plate II. Fig. 10). The upper Oolite at Portland con-
tains an interesting bed, about a foot in thickness, of a dark
brown substance. This is the Dirt-bed (Fig. 86) made up of
black loam, which, during the Purbeck period, formed a sur-
face soil which was penetrated by the roots of trees, frag-
ments of whose stems are now found in it fossilised. These
consist of an assemblage of silicified stumps or stools of large
trees, from 1-3 feet high, standing in their original position,

Fig. 86. Fig. 87.

with the roots remaining attached to them, and still pene-
trating the earth in which they grew. Besides the erect trunks
many stems haye been broken and throAvn down, and are buried
in a horizontal position in the bed. They belong to Conifera)
and Cycadace^. One of these is Mantellia nidiformis, shown in
Fig. 87. Carpolithes conicus and C. Bucklandi are fruits found
in the Oolite. Some look upon them as fruits of palms.

Fig. 86. The Dirt-hed of the Island of Portland, containing stumps
of fossil Cycadacese in an erect position.

Fig. 87. Cycadoidea megalophylla (Mantellia nidiformis of Brong-
niart), a subglobose depressed trunk, with a concave apex, and with
the remains of the petioles disposed in a spiral manner, the markings
being transversely elliptical. It is found in the Oolite of the Island
of Portland, in a silicified state.

84

PAL^ONTOLOGICAL BOTANY.

Several species of Pandanaceoiis fruits have been found
in Oolitic strata. Buckland described one of them as Podo-
carya, which is remarkable, as it consists of a single but many-
seeded drupe. To another form, more nearly allied to the
existing plants, Carruthers has given the name Kaidacarpum,
and has described three species. These fruits are made up of
a large number of single - seeded drupes. The species
figured (Fig. 88) is from the great Oolite, near Northampton.

Fit?. 88.

Fi?. 89.

In Fig. 89 a representation is given of one of the Pan-
danacete, the screw-pines of the present day.

The flora of the Wealden epoch is characterised in the
south of England by the abundance of the fern called Loncho-
pteris Mantellii, and in Germany by the predominance of the
Conifer denominated Abietites Linkii (Fig. 90), and the pre-
sence of Araucarites Pippingfordensis, as well as by numerous
Cycadaceas, such as species of Cycadites, Zamites, Pterophyl-
lum, Mantellia, Bucklandia, and a remarkable genus having a
fleshy fruit, and related to the ordinary Cycadaceas as Taxus
is to the other Coniferee, which has been fully described in

Fig. 88. Kaidacarimm ooliticum, Carr., fruit of a fossil allied to
Pandanacete, from the great Oolite near Northampton.

Fig. 89. Pandanus odoratissimus, Screw-pine, with adventitious roots.

FLORA OF THE WEALDEN EPOCH.

85

the Linn. Trans., under the name of Bennettites (Plate II.
Fig. 3). In the Wealden at Brook Point, Isle of Wight,
Cycads have been detected allied to Encephalai-tos. The
fruits of them are described by Carruthers as Cycadeostrobus.
He describes the following species : — Cycadeostrobus oyatus
(Plate II. Fig. 1), C. truncatus, C. tumidus, C. elegans, C.
Walkeri, C sphtericus, in the Oxford
clay of Wiltshire ; C. prima3vus in the
inferior Oolite at Burcott Wood and
Livingston, and C Brunonis. Mantell
states that he has found 40 or 50 fossil
cones in the Wealden of England ; they
belong either to the genus Cycadeo-
strobus or to the pines mentioned below
as occurring in the Wealden. The
Wealden fresh-water formation termi-
nates the reign of Gymnosperms. Car-
ruthers gives the following list of the remains of Conifene
which have been found in the secondary strata of Britain,
excluding the Trias : —

Upper Chalk. — Wood in flint nodules.

Upper Greensand. — Foliage and cone of Sequoiites Woodwardii 3
cone of Pinites oblongus.

Gault. — Cones of Pinites gracilis and P. hexagoniis, Sequoiites
Gardneri and S. ovalis.

Lower Greensand. — Water-worn and bored pieces of wood ; cones
of Pinites Benstedi, P. Sussexiensis, and P. Leckenbyi.

Wealden. — Driftwood, foliage' of Abietites Linkii; cones of Pinites
Dunkeri, P. Mautellii, P. patens, and P. Fittoni, and of Ai'aucaria
Pippingfordensis ; foliage (and drupes 1) of Thuites Kurrianus.

Purbeck. — Fossil forest in situ at Isle of Portland ; cone " nearly
related to Araucaria excelsa " in the Dirt-bed.

Portland Stone. — Driftwood Araucarites.

Kimmeridge Clay. — Cone of Pinites depressus.

Ficr, 90.

Fig. 90. Fossil Wood, Ahietites LinJcii. A Coniferous plant from
the Wealden, showing punctated woody tissue and medullary rays.

86 PALJEONTOLOGICAL BOTANY.

Oxford Clay. — Driftwood and foliage of Araucarites.

Great Oolite. — Driftwood of Araucarites ; foliage of Thuites
aciitifolius, T. articiilatus, T. cupressiformis, T. divaricatiis, and T.
expansiis, and of Taxites podocarpoides ; detached cones at Helmsdale,
Sutherland.

Inferior Oolite. — Wood of Pence Eggensis (Tertiary according
to Geikie) ; foliage of Brachyphyllum niammillare, Cryptomerites 1
divaricatus, and Palissya 1 Williamsonis ; cones of Araucarites sphsc-
rocarpus, A. Brodiei, and A. Phillipsii. Pinites primseva (Lindl. and
Hutt.) is a Cycadean fruit.

Lias. — Wood of Pinites Huttonianus and P. Lindleyanus ; foliage
of Araucaria peregrina and Cupressus latifolia ; cone of Pinites elon-
gatus, and " cone with long bracts lil^ those of Pinus bracteata," from
Cromarty.

Carruthers gives the following arrangement of fossil Cyca-
dacege in the Transactions of the Linn. Soc. vol. xxvi. —
Firstly, the Cycadefe : including the genus Bucklandia, Presl ;
and species B. anomala, B. Mantellii, B. squamosa, B. Mil-
leriana — the two first-named species being from the Wealden,
and the two last-named from the Oolite, Secondly, the
Zamieas : including the genus Yatesia, Carr. ; and species Y.
Morrisi, Lower Cretaceous ; Y. gracilis, Lias ; Y. crassa, M.
Oolite ; Y. Joassiana, M. Oolite : the genus Fittonia, Carr.,
and species F. squamata, U. Cretaceous ; the genus Crosso-
zamia, Pomel, and species C. Moreaui, Pomel, Jurassic, and
C. Buvignieri, Pomel, Jurassic — both from St. Michel, France.
Thirdly, the Williamsonie^ : including the genus William-
sonia, Carr. ; and species W. gigas, W. pecten, W. hastula, all
from the inferior Oolite. Fourthly, the Bennettiteas : includ-
ing the genus Bennettites, Carr., and species B. Saxbyanus,
Wealden ; B. Gibsonianus, Lr. Greensand ; B. maximus,
Wealden ; B. Portlandicus, Lr. Purbeck ; and B. Peachianus,
I\L Oolite : the genus Mantellia, Brong., and species M. nidi-
formis, M. intermedia, M. microphylla, from the Lr. Purbeck ;
and M. inclusa, from the Lr. Cretaceous ; the genus Raumeria,
Goeppert, and species R. Reichenbachiana, from Galicia, and
R. Schulziana from Silesia.

FLORA OF THE CAINOZOIC PERIOD. 87

FOSSIL FLORA OF THE TERTIARY OR

CAINOZOIC PERIOD,

(including the cretaceous epoch).

Reign of Angiosperms.

This reign is characterised bj the appearance of Angio-
spermous Dicotyledons, plants which constitute more than
three-fourths of the species of the existing flowering plants
of the globe, and which appear to have acquired the pre-
dominance from the commencement of the Tertiary epoch.
They are plants with seeds contained in seed-vessels, and
each seed with two cotyledons. These plants, however,
appear even at the beginning of the Cretaceous period.
In this reign, therefore, Brongniart includes the upper
Secondaiy period, or the Cretaceous system, and all the
Tertiary period. The Cretaceous may be considered as a
sort of transition period between the reign of Gymnosperms
and Angiosperms. The Chalk flora is characterised by the
Gymnospermous almost equalling the xVngiospermous Dicoty-
ledons, and by the existence of a considerable number of
Cycadacea3, which do not appear in the Tertiary period. The
genus Credneria is one of the characteristic fomis. In this
period we find Alg^ represented by Cystoseirites, Confervites,
Sargassites, and Chondrites; Ferns by peculiar species of
Pecopteris and Protopteris ; Naiadaceas by Zosterites ; Palms,
by Flabellaria and Palmacites; Cycadace^e by Cycadites,
Zamites, Microzamia, Fittonia, and Bennettites ; Coniferas,
by Brachyphyllum, Widdringtonites, Cryptomeria, Abietites,
Pinites, Cunninghamites, Dammarites, Araucarites ; and An-
giospennous Dicotyledons, by Comptonites, Alnites, Carpi-
nites, Salicites, Acerites, Juglandites, and Credneria. At the
base of the Tertiary period there are deposits of Algce of a
very peculiar form, belonging to the genera Chondrites and
Munsteria. No land plants have been found mingled with
these marine species.

88

PALiEONTOLOGICAL BOTANY.

In the Gault, near Folkestone, an interesting association
of coniferous fruits has been found, consisting of two species

of Sequoia, along with two of Pinus.
The pines belong to the same group
as those which now grow with the Wel-
lingtonias in California, showing the
remarkable fact that the coniferous
vegetation of the high lands of the
Upper Cretaceous period had a fades
similar to that now existing in the
mountains on the west of North
America. We figure both the species
of Sequoiites — viz. S. ovalis (Fig. 91), a
large cone, and S. Gardneri (Plate 11.
Fig. 7). In the present day there are
two species of the genus Sequoia —
viz. S. gigantea (Wellingtonia gigantea)
and S. sempervirens.* In the Lower
Greensand a remarkably fine cone belonging to the same
group as the Cedar has been found. This is the Pinites Leck-
enbyi (Plate II. Fig. 4). A section exhibits the seeds in
their true position, some of which are preserved so as to
exhibit the form and position of the embryo.

The Tertiary period is characterised by the abundance of
Angiospermous Dicotyledons and of Monocotyledons, more
especially of Palms. By this it is distinguished from the
more ancient periods. Angiosperms at this period greatly
exceed Gymnosperms. Cycadace^e are very rare, if not com-
pletely wanting, in the European Tertiary strata, and the
Conifera3 belong to genera of the temperate regions. In the
lower Tertiaries Carruthers has found a fossil Osmunda, and
the existence of a group of Pines having cones with a very
thick apophysis. From their remarkable external aspect.

Fig. 91.

Fig. 91. Sequoiites ovalis.

Large cone.

* Carruthers, Geol. Mag., vol. viii. December 1871.

FLORA OF THE CAINOZOIO PERIOD.

89

these cones had been considered to be Cjcadean, but their
internal structure indicates that they are coniferous. Pinites
ovatus is one of these cones (Fig. 92). The Cupres-
sinea3 are found in the Tertiary beds only. Taxodiese are
represented by Sequoiites (Plate II. Fig. 7) in the Cretaceous
and Eocene strata. Pence australis of Van
Diemen's Land and P. Pritchardi of Ire-
land are Tertiary plants. The Pence of
Eigg (P. Eggensis), according to Geikie, is
also Tertiary, and not Oolitic. Isoetes is
mentioned by Schimper as a Tertiary genus.
Although the vegetation throughout the
whole of the Tertiary period presents pretty
uniform characters, still there are notable
differences in the generic and specific forms,
and in the predominance of certain orders at different epochs.
Brougniart does not entirely agree with linger as to these
epochs. Many of the formations classified by Unger in the
Miocene division he refers with Raulin to the Pliocene. He
divides the Tertiary period, as regards plants, into the Eocene,
IVIiocene, and Pliocene epochs, and gives the following com-
parative results from an examination of their floras : —

Fiir. 92.

Classes and Sub-Classes.

Eocene Epoch.

Miocene Epoch.

Pliocene Epoch.

Thallogenae

16
17
33

40
103

6

4

26

19

78

6

7
4

31

164

Acrogeiice

Monocotyledones

Dicotyledones —

GyinnospermtB

Angiospernise

209

133

212

In the Eocene formation the fossil fruits of the Isle of

Fig. 92. Pinites ovatus (Zamia ovata of Lindley and Hutton), an
ovate cone with a truncated base and obtuse apex, nearly allied to tlie
stone-pine.

90

PAL^ONTOLOGIOAL BOTANY.

Sheppey increase the number of Phanerogamous plants, only
a small proportion of which have as yet been described. This
is an exceptional locality, and the deposit in which the fruits
occur is probably the silt found at the mouth of a large river
which flowed, like the Nile, from tropical regions towards the
north. The number of plants as given by Brongniart is much
smaller than that mentioned by Unger (p. 23). The latter
includes in his enumeration a considerable amount of uncer-
tain species.

The Eocene epoch in general is characterised by the predo-
minance of Alg^ and marine Naiadace^, such as Caulinites and
Zosterites ; by numerous Conifers, the greater part resembling
existing genera among the Cupressine^, and appearing in the
form of Juniperites, Thuites, Cupressinites (Plate II. Figs. 8, 9),
Callitrites, Frenelites, and Solenostrobus ; by the existence of a

number of extra-European
forms, especially of fruits.
W\ such as Nipadites, Legu-
^'''^' minosites, Cucumites, and
Hightea ; and by the pre-
sence of some large species
of Palm belonging to the
genera Flabellaria and
Palmacites (Fig. 93).

Unger says that the
Eocene flora has resembled
in many respects that of
the present Australian vegetation. He gives the following
genera as occurring at the Eocene epoch : — Araucaria, Podo-
carpus, Libocedrus, Callitris, Casuarina, Pterocarpus, Dre-
panocarpus, Centrolobium, Dalbergia, Cassia, Cfesalpinia,
Bauhinia, Copaifera, Entada, Acacia, Mimosa, Inga. (See-
mann's Journal of Bot. vol. iii. p. 43.) Amber is considered

Fig. 93. Palmacites Lamanonis. Fan-shaped (flabellate) leaf of a
Palm.

FLORA OF THE EOCENE EPOCH.

91

Cryptogamese
Phaneroorameoe

Amber Flora,
60
102

to be the produce of many Conifers of tMs epoch, such as
Peuce succinifera or Pinites succinifera, and Pinus Rinkianus.
It occurs in East Prussia in great quantity, and it is said that
many pieces of fossil wood occur there, which, when mode-
rately heated, give out a decided smell of amber. Connected
with these beds are found cones belonging to Pinites sylves-
trina and P. Pumilio-miocena, species nearly allied to the
living species ; others to Pinites Thomasianus and P. brachy-
lepis. Goeppert contrasts the present flora of Germany and
that of the Amber epoch as follows : —

German Flora.

6800
3454

and gives the following specimens of two of the orders : —

Ciipulifer^ . . 12 10

Ericaceae ... 23 24

(See remarks by Goeppert on the Amber Flora, etc., Edin.

N. Phil. Journ. Ivi. 368; and Quart. Journ. Geol. Soc. x.

37.) In the lower Eocene of Heme

Bay, Carruthers noticed a fern like

Osmunda (Fig. 94), which he calls

Osmundites Dowkeri (Plate I. Figs.

8, 9). This specimen was silicified;

starch grains contained in its cells,

and the mycelium of a parasitic fungus

traversing some of them, were perfectly

preserved. Berkeley has detected in

amber fossil fungi, which he has

named Penicillium curtipes, Brachy-

cladium Thomasinum, and Strepto-

thrix spiralis.* Some Characese are also met with, as

Fig. 94. Osmunda regalis, Royal Fern, having a bipinnate frond
and fructification in a spike-like form, the branches bearing sporangia.

* Annals and Mag. of Nat. Hist. 2d ser. ii. 380.

92

PAL^ONTOLOGICAL BOTANY.

Chara meclicaginiila and C. prisca, with a fossil called
Gjrogonites, the nucule or the fructification of these plants.
Carpolithes ovatus, a minute seed-vessel, occurs in the Eocene
beds of Lewisham. Another small fruit, of a similar nature,
called Folliculites minutulus, occurs in the Bovey Tracey coal,
which belongs to the Tertiary beds.

The most striking characters of the Miocene epoch consist
in the mixture of exotic forms of warm regions with those of
temperate climates. linger says that it resembles that of the
southern part of North America. Thus we meet with Palms,
such as species of Flabellaria and Phoeni-
cites, a kind of Bamboo called Bambusium
sepultum; Lauracea3, as Daphnogene and
Laurus ; Combretaceae, as Getonia and Ter-
minalia ; Leguminos^, as Phaseolites,
Desmodophyllum, Dolichites, Eiythrina,
Bauhinia, Mimosites, and Acacia — all plants
haying their living representatives in warm
j^ climates; Echitonium, Plumiera, and other
Apocynacese of equatorial regions ; Comp-
tonia (Fig. 95), a Proteaceous genus, and
Steinhauera, a Cinchonaceous genus;
mingled with species of Acer (Fig. 96), Ulmus
(Fig. 97), Rhamnus (Fig. 98) ; and Amenti-
ferous forms, such as Myrica, Betula, Alnus (Fig. 99), Quercus,
Fagiis, Caq^inus, all belonging to temperate and cold climates.
The statements as to the occurrence of Pinus sylvestris and
Betula alba among the Miocene fossils have not been founded
on complete data. It is by no means easy, even in the present
day, to distinguish fragments of dried specimens of Pinus
Pumilio from those of P. sylvestris, and from a great many

Fis. 95.

Fig. 95. Comptonia acutiloha, apparently the leaf of a jjlant belong-
ing to the natural order Proteacese, which abound in Australia, and are
also found at the Cape of Good Hope at the present day.

FLORA OF THE MIOCEXE EPOCH.

93

other Pines. The difficulty is still greater in fossils (Hook.
Kew JouiTi. T. 413. There are a very small number of
plants belonging to ordei*s with gamopetalous corollas. In

Fi?. 96.

FiiT. 97

the Miocene formation of Lough Xeagh in Ireland, and of
Mull in Scotland, silicified trunks of considerable size have
been foimd. The Irish silicified wood has been denominated
Cupressoxylon Pritchardi from its apparent resemblance to the
Cypress. As connected with the Miocene epoch, we may
notice the leaf-beds found at Ardtun, in the island of Mull,

Figures 96 to 99 show the leaves of plants belonging to the
Miocene epoch.

Fig. 96. Acer triloba turn, a three-lobed palmate leaf, like that of
the Maple, with the lobes unequal, inciso-dentate, the lateral ones
spreading, found at (Euingen. Fig. 97. Ubnus Bronnii, a petiolate
leaf, like that of the Elm, unequally ovato-acuniinate, feather-veined

94

PAL^ONTOLOGICAL BOTANY.

by the Duke of Argyll.* Above and below these beds basalt
occurs, and there are peculiar tufF-beds alternating with the

Fig. 98.

leafy deposits. These tufF-beds were formed by the deposit
of volcanic dust in pools probably of fresh water. They
contain fragments of chalk and flint. The leaves are
those of plants allied to the Yew, Rhamnus, Plane, and
Alder, along with the fronds of a peculiar Fern, and the
stems of an Equisetum. The genera are Taxites or Taxo-
dites (Fig. 100), Rhamnites (Fig. 101), Platanites, Alnites,

and toothed, found in Bohemia. Fig. 98. Rhamnus Aizoon, a petiolate
elliptical obtuse feather-veined leaf, with an entire margin, found in
Styria.

* Journ. Geol. Soc. of London, vii.

FLORA OF THE MIOCENE EPOCH.

95

Filicites, and Eqiiisetum (Fig. 102). In the leaf-beds at
Bournemouth Mr. Wanklyn detected several ferns. One is

Fiff. 100.

Fig. 99.

Fig. 101.

a species of Dldymosorus, and shows distinct venation and
fructification. Fossilised v^^ood was found in the Arctic
Regions by Captain M'Clure. At the KW. of Banks Land
he found trees with tmnks 1 foot 7 inches in diameter.

Fig. 99. Almis gracilis, an ovate-oblong leaf, like that of the Alder,
found in Bohemia.

Figures 100, 101, 102, exhibit fragments of plants which occur in
the leaf-bed at Ardtun Head, in Midi, and which is referred to the
Miocene epoch. The figures are from the Duke of Argyll's paper.

Fig. 100. Taxites, or perhaps Taxodites Camidhellii, a branch with
leaves resembling those of the Yew, or rather those of Taxodium.
Fio-. 101. Rham7iiUs multinervatus, a leaf resembling that of Khamnus.

96 PAL^ONTOLOGICAL BOTANY.

Dr. Oswald Heer'" has examined the plants preserved in
the lignite beds of Bovey Tracey, in Devonshire, and he finds
that they belong to the Miocene formation. There
is a remarkable coincidence between this and several
of the continental fossil floras, such as those of Salz-
hauser in the Wetterau, Manosque in Provence, and
of some parts of Switzerland. Bovey Tracey has no
species in common with Iceland, although the Tertiary
flora of Iceland belongs to the same period. Two of its
species (Corylus MacQuarrii and Platanus aceroides)
have been found in the Miocene of Ardtun Head.
Even the genera are distinct, with the exception of
Sequoia and Quercus. The Bovey Tracey flora has a
much more southern character, corresponding entirely

Fio", 102.

with that of the Lower Miocene of Switzerland. It
contains three species of Cinnamon, one Laurel, evergreen Figs,
one Palm, and large Ferns, thus manifesting a subtropical
climate. One of the most important plants is Sequoia Coutt-
si^, a Conifer which supplies a link betAveen S. Langsdorfii
and S. Sternbergi, the widely-distributed representatives of
S. sempervirens and S. gigantea (AYellingtonia), which are Cali-
fornian trees. Among other characteristic plants may be men-
tioned Cinnamomum lanceolatum and C. Scheuchzeri ; Quercus
Lyellii, an evergreen oak ; species of evergreen fig (Ficus Fal-
coneri and F. Pengellii), Palmacites Da3monorops, a prickly
twining Rotang-palm ; species of Vine (Yitis Ilookeri and V.
Britannica) ; Pecopteris lignitum, a large tree-fern ; species of
Nyssa, at present confined to North America. Among other
plants recorded by Heer in his paper are the following : — Lau-
rus primigenia, Daphnogene Ungeri, species of Dryandroides,
Andromeda, Vaccinium acheronticum, Echitonium cuspidatum,

Fig. 102. Equisetum Camphellii, a stem like that of an Equisetum of
the present day.

* Philosophical Transactions, R. Soc. Lond., vol. clii. p. 1039.

FLORA OF THE MIOCENE EPOCH. 97

Gardenia Wetzleri, species of Anona, Nyniphaea Doris,
Carpolithes Websteri, C. Boveyanus, and other species. In
the post-tertiary white clay of Bovey Tracey, Salix cinerea,
and a species allied to S. repens, as well as Betula nana, are
found.

The Arctic fossil flora (Miocene), according to Heer,
amounts to 162 species : Crypt ogamia, 18 species, of which
9 are large ferns ; Phanerogamia, Coniferte, 31 ; Monocoty-
ledons, 14; Dicotyledons, 99. Among the Coniferge are —
Pinus M'Clurii, Sequoia Langsdorfiii, Sternbergi, and Coutt-
siae, Taxodium dubium, Glyptostrobus europgeus, Thujopsis
europgea. Among leafy trees are — Fagus Deucalionis, Quer-
cus Olafseni, Platanus aceroides, willows, beeches, Acer,
Otopteryx, tulip-tree, walnuts. Magnolia Inglefieldi, Prunus
Scottii, Tilia Malmgreni, Corylus INPQuarrii, Alnus Kefer-
steinii, Daphnogene Kaimii, probably one of the Laurace^e ;
and among Proteaceas, MacClintockia ? and Hakea. In
Greenland are found species of Rhamnus, Paliurus, Cornus,
Ilex, Crata3gus, Andromeda, ]\Iyrica, Ivy, and Vine. From
the flora of Spitzbergen, in the IVIiocene epoch, we may con-
clude that under 79° N. lat. the mean temperature of the
year may have been 41° Fahr., while at the same epoch that
of Switzerland was 69°-8 Fahr. ; judging from the analogy of
floras, it appears that the mean temperature has fallen 6° -9.
From this it follows that at Spitzbergen, at 78° IS", lat., the
mean temperature was perhaps 41°-9 Fahr. In Greenland,
at 70°, it would be 49°-l Fahr., and in Iceland and on the
Mackenzie, in lat. 65°, it would be 52°-7 Fahr. At the
Miocene epoch the temperature seems to have been much more
uniform, the mean heat diminishing much more gradually in
proportion as the pole was approached. The isothermal
line of 32° Fahr. might have fallen upon the pole, while now
it is situated under 58° N. (See Heer's conclusions as to
changes of temperature depending on proportion of sea and

H

98 PAL^ONTOLOGICAL BOTANY.

land, eccentricity of tlie eartli, and the earth moving through
warm and cold spaces in the universe — Ann. Nat. Hist. 4th
ser. i. 66.)

In speaking of the Polar flora of former epochs, Heer says that
every plant executes a slow and continuous migration. These
migrations, the starting-point of which is the distant past, are
recorded in the rocks ; and the interweaving of the carpets of
flowers which adorn our present creation retraces them for us
in its turn. For the vegetation of the present day is closely
connected with that of preceding epochs ; and throughout all
these vegetable creations reigns one thought, which not only
reveals itself around us by thousands upon thousands of
images, but strikes us everywhere in the icy regions of the
extreme north. Organic nature may become impoverished
there, and even disappear when a cold mantle of ice extends
over the whole earth; but where the flowers die the rocks
speak, and relate the marvels of creation ; they tell us that
even in the most distant countries, and in the remotest parts,
nature was governed by the same laws and the same harmony
as immediately around us."*"

The flora of the Pliocene epoch has a great analogy to
that of the temperate regions of Europe, North America, and
Japan. We meet with Conifera3, Amentiferas, Rosace£e, Le-
guminosae, RhamnaccEe, Aceraceae, Aquifoliaceas, Ericaceae,
and many other orders. There is a small number of Dicoty-
ledons with gamopetalous corollas. The twenty species with
such corollas recognised by Brongniart are referred to the
Hypogynous Gamopetalous group of Exogens, which in the
general organisation of the flowers approach nearest to Dialy-
petalee. In this flora there is the predominance of Dicotyle-
dons in number and variety ; there are few Monocotyledons.

* Heer, Flore Fossile des Regions Polaires, Zurich ; also Biblio-
theque Univ. xxxix. p. 12; see also Ann. Nat. Hist. 4th ser. i. 61,
iv. 81.

FLORA OP THE PLIOCENE EPOCH. 99

No species appear to be identical, at least with the plants
which now grow in Europe. Thus the flora of Europe, even
at the most recent geological epoch of the Tertiary period,
was very different from the European flora of the present day.
Taking the natural orders which have at least four repre-
sentatives, Raulin'"' gives the following statement as to the
Tertiary flora of central Europe. The Eocene flora of Europe
is composed of 128 species, of which 115 belong to Algse,
Characea3, Pandanace^, Palmas, Naiadaceas, Malvace^, Sapin-
daceae, Proteace^e, Papilionacese, and Cupressineas. The
Miocene flora has 112 species, of which 69 belong to Algge,
Palmee, Naiadacece, Apocynace^e, Acerace^, Lauracese, Papi-
lionace^, Platanaceas, Quercinea3, Myricace^e, and Abietinege.
The Pliocene flora has 258 species, of which 226 belong to
Algas, Fungi, Musci, Filices, Palmas, Ericaceas, Aquifoliacege,
Aceracea3, Ulmaccfe, Rhamnacea3, Papilionacea3, Juglandacese,
Salicaceas, Quercine^e, Betulacete, Taxaceae, Cupressineee,
and Abietine^e. The Eocene species are included in genera
which belong at the present day to inter-tropical regions,
comprising in them India and the Asiatic islands of Australia.
Some are peculiar to the Mediterranean region. The aquatic
plants, which form almost one-third of the flora, belong to
genera now peculiar to the temperate regions of Europe and
of North America, or occurring everywhere. The Miocene
species belong to genera, of which several are found in India,
tropical America, and the other inter-tropical regions, but
which for the most part inhabit the sub-tropical and temperate
regions, including the United States. Some of the genera
are peculiar to the temperate regions. The aquatic genera,
poor in species, occur everywhere, or else solely in the tem-
perate regions. The Pliocene species belong to genera which
almost all inhabit the temperate regions, either of the old

* Raulin, sur les Transformations de la Flore de TEurope centrale
pendant la periode Tertiaire. — Ann. des Sc. Nat. 3d ser. Bot. x. 193.

100 PAL^ONTOLOGICAL BOTANY.

continent or of the United States. A few only are of genera
existing in India, Japan, and the north of Africa. These
various floras, which present successively the character of
those of inter-tropical, sub-tropical, and temperate regions,
seem to indicate that central Europe has, since the com-
mencement of the Tertiary period, been subjected, during the
succession of time, to the influence of these three different
temperatures. It would appear, then, Raulin remarks, that
the climate of Europe has during the Tertiary period gra-
dually become more temperate.

Brown coal occurs in the upper Tertiary beds, and in it
vegetable structure is easily seen under the microscope.
Goeppert, on examining the brown coal deposits of northern
Germany and the Rhine, finds that Coniferge predominate in
a remarkable degree; among 300 specimens of bituminous
wood collected in the Silesian brown coal deposits alone, only
a very few other kinds of Exogenous wood occur. This seems
remarkable, inasmuch as in the clays of the brown coal for-
mation in many other places leaves of deciduous Dicotyle-
donous trees have been found ; and yet the stems on which
we may suppose them to have grown are wanting. The leaves
have been floated away from the place where they grew by a
current of water which was not powerful enough to transport
the stems. The coniferous plants of these brown coal deposits
belong to Taxine^e and CupressineaB chiefly ; among the plants
are Pinites protolarix and Taxites Ayckii. Many of the Coni-
ferse exhibit highly compressed, very narrow annual rings, such
as occur in Coniferee of northern latitudes. Goeppert has
described a trunk, or rather the lower end of a trunk, of
Pinites protolarix, discovered in 1849 in the brown coal of
Laasan in Silesia. It was found in a nearly perpendicular
position, and measured more than 32 feet in circumference.
Sixteen vast roots ran out almost at right angles from the
base of the trunk, of which about four feet stood up perfect

GENERAL CONCLUSIONS. 101

in form, but stripped of bark. Unfortunately the interior of
the stem was ahnost entirely filled with structureless brown
coal, so that only two cross sections could be obtained from
the outer parts, one sixteen inches, the other three feet six
inches broad. In the first section Goeppert counted 700, in
the second 1300 rings of wood, so that for the half-diameter
of 5 J feet, at least 2200 rings must have existed. As there
is every reason to believe that the rings were formed in earlier
ages just as the annual zones are now, this tree would be
from 2200 to 2500 years old. Exogenous stems in lignite
are often of great size and age. In a trunk near Bonn,
Noggerath counted 792 annual rings. In the turf bogs of
the Somme, at Yseux near Abbeville, a trunk of an oak-tree
has been found above 14 feet in diameter.

>Ye have thus seen that the vegetation of the globe is
represented by numerous distinct floras connected with the
different periods of its history, and that the farther back we
go, the more are the plants diff'erent from those of the present
day. There can be no doubt that there have been successive
deposits of stratified rocks, and successive creations of living
beings. We see that animals and plants have gone through
their different phases of existence, and that their remains in
all stages of growth and decay have been imbedded in rocks
superimposed upon each other in regular succession. It is im-
possible to conceive that these were the result of changes pro-
duced within the limits of a few days. Considering the depth
of stratification, and the condition and nature of the living
beings found in the strata at Various depths, we must conclude
(unless our senses are mocked by the phenomena presented
to our view) that vast periods have elapsed since the Creator
in the beginning created the heavens and the earth. How
far it may be possible in the future to correlate the history of
the earth inscribed on its rocky tablets and deciphered by the
geologist, and that short narrative which forms the introduc-

102 PAL^ONTOLOGICAL BOTANY.

tiou to the Sacred Volume, it is to difficult to say. At
present there are no satisfactory materials for such a correla-
tion ; but one thing is certain, that both Revelation and
Geology testify with one voice to the work of a Divine
Creator.

" Who shall declare (Hugh Miller remarks) what through
long ages the history of creation has been ? We see at wide
intervals the mere fragments of successive Floras ; but know
not how, what seem the blank interspaces, were filled ; or
how, as extinction overtook in succession one . tribe of
existences after another, and species, like individuals, yielded
to the great law of death, yet other species were brought to
the birth, and ushered upon the scene, and the chain of being
was maintained unbroken. We see only detached bits of that
green web which has covered our earth ever since the dry
land first appeared. But the web itself seems to have been
continuous throughout all time; though, as breadth after
breadth issued from the creative loom, the pattern was altered,
and the sculpturesque and graceful forms that illustrated its
first beginnings and its middle spaces have yielded to flowers
of richer colour and blow, and fruits of fairer shade and out-
line ; and for gigantic club-mosses stretching forth their hir-
sute arms, goodly trees of the Lord have expanded their
great boughs ; and for the barren fern and the calamite clus-
tering in thickets beside the waters, or spreading on flowerless
hill-slopes, luxuriant orchards have yielded their ruddy flush,
and rich harvests their golden gleam."

When we find animals and plants, of forms unknown at
the present day, in all stages of development, we read
a lesson as to the histoiy of the earth's former state as
conclusive as that which is derived from the Nineveh relics
(independent of Revelation) in regard to the history of
the human race. There is no want of harmony between

RECAPITULATION. 103

Scripture and Geology. The Word and the Works of God
must be in unison, and the more we truly study both, the
more they will be found to be in accordance. Any apparent
want of correspondence proceeds either from imperfect inter-
pretation of Scripture or from incomplete knowledge of science.
The changes in the globe have all preceded man's appearance
on the scene. He is the characteristic of the present epoch,
and he knows by Revelation that the world is to undergo a
further transformation, when the elements shall melt with
fervent heat, and when all the present state of things shall
be dissolved, ere the ushering in of a new earth, wherein
righteousness is to dwell.

Recapitidation of the chief points connected with
Fossil Botany : —

1. The vegetation of the globe has varied at difFereut epochs of the

earth's history.

2. The farther we recede in geological history from the present day,

the greater is the difference between the fossil plants and those
which now occupy the surface.

3. All fossil pkints may be referred to the great classes of plants of

the present day, Acotyledons, Monocotyledons, and Dicoty-
ledons.

4. The fossil species are diflferent from those of the present flora, and

it is only when we reach the Tertiary periods that we meet
with some genera which are without doubt identical.

5. Fossil plants are preserved in various conditions, according to the

nature of their structure, and the mode in which they have
been acted upon. Sometimes mere casts of the plants are
found, at other times they are carbonised and converted into
coal, while at other times, besides being carbonised, they are
infiltrated with calcareous or siliceous matter, and finally, they
may be petrified.

6. Cellidar plants, and the cellular portions of vascular plants, have

rarely been preserved, while woody species, and especially
Ferns, which are very indestructible, have retained their forms
in many instances.

7. In some cases, especially when silicified or charred, the stmcture

104 PAL^ONTOLOGICAL BOTANY.

of the woody stems can be easily seen in thin sections under
the microscope.

8. The determination of fossil plants is a matter of great difficulty,

and requires a thorough knowledge of structure, and of the
markings on stems, roots, etc.

9. The rocks containing organic remains are called fossiliferous, and

are divided into Primary, Secondary, and Tertiary, or into
Palseozoic, Mesozoic, and Cainozoic, each of these series being
characterised by a peculiar facies of vegetable life.

10. The mere absence of organic remains will not always be a correct

guide as to the state of the globe.

11. The number of fossil species has been estimated at between 3000

and 4000 ; but many parts of j^lants are described as separate
species, and even genera, and hence the number is perhaps
greater than it ought to be.

12. Brongniart divides the fossil flora into three great epochs : — 1.

The reign of Acrogens ; 2. The reign of Gymnosperms ; 3. The
reign of Angiosperms.

13. The reign of Acrogens embraces the Silurian, Carboniferous, and

Permian epochs, in which there was a predominance of plants
belonging to the natural orders Filices, Lycopodiacese, and
Equisetacese, associated, however, with others of a higher class.

14. The reign of Gymnosperms embraces the lower and middle

Secondary periods, and is characterised by the presence of
numerous Coniferse and Cycadacese.

15. The reign of Angiosperms includes the Cretaceous and Tertiary

periods, and is marked by the predominance of Angiospermous
Dicotyledons.

16. Coal is a vague term, referring to all kinds of fuel formed from

the chemically-altered remains of plants.

17. When there is a great admixture of mineral matter, so that it will

not burn as fuel, then a shale is produced.

18. The microscopic structure of Coal probably varies according to

the nature of the plants of which it is composed, and the
changes produced by pressure, heat, and other causes. Cell-
ular tissue, punctated woody tissue, and scalariform vessels,
have been detected in it.

19. Certain temporary and local floras seem to have given origin to

peculiar layers of coal.

20. During the Carboniferous epoch we meet with Ferns, Sigillarias,

and their roots called Stigmarias, Lepidodendrons, Uloden-
_drons, Calamites, Gymnosperms, etc.

LITERATURE OF THE SUBJECT. 105

21. The plants forming coal have grown in the basin where the coal

is found ; but sandstone rocks in the coal-measures deposited
by water having a considerable velocity, and consequently
carrying power, contain sometimes trunks of large trees which
have been drifted like snags.

22. The strata between the Permian epoch and Chalk display nume-

rous Gymnosperms, especially belonging to the Cycadaceous
Order. Some of them exhibit limited coal deposits.

23. The Chalk and Tertiary strata display not only Acrogens and

Gymnosperms, but also Angiospermous Dicotyledons, some of
which, at the Miocene period, belong apparently to genera of
the present day.

24. Brown Coal occurs in the Upper Tertiary beds, and in it vegetable

structure is easily seen under the microscope.

25. Raulin thinks that during the Tertiary epoch the flora of Europe

has gradually assumed a more temperate character.

26. The Eocene flora, according to linger, resembled in many respects

that of Australia at the present day.

27. The Miocene flora is characterised by a number of exotic forms of

warm regions with those of temperate climates. It is largely
seen in the Arctic Regions.
29. The Pliocene flora has great analogy with that of the temperate
regions of Europe, North America, and JajDan.

On the subject of Fossil Botany the following works may
be consulted : —

Abhandlungen der Kaiserlich Koniglichen Geologischen Reichsanstalt,

Band. ii. Wien. 1855.
Argyll, Duke of, on Tertiary Leaf-Beds in the Isle of Mull, Journ.

Geol. Soc. Lond., vii. May 1851.
Balfour, J. H., on certain Vegetable Organisms in Coal from Fordel,

Trans. R.S.E., vol. xxi. p. 187.
Baily, W. H., Figures of Characteristic British Fossils, 1871-2.
Bennett, J. Hughes, on the Structure of Torbane Hill Mineral and

other Coals, Trans. R. Soc. Ed., vol. xxi. p. 173.
Binney, E. AV., on Calamites and Calamodendron, Palseontographical

Society's Memoirs, 1868.
on the Structure of Fossil Plants found in the Carboniferous

Strata. Palseontographical Society's Memoirs, 1871.
Description of some Fossil Plants, showing Structure in the

106 PALiEONTOLOGICAL BOTANY.

Lower Coal Seam of Lancaster and Yorkshire, Phil. Trans., vol.

155, p. 579.
Bowerbank, Fossil Fruits and Seeds of the London Clay.
Brongniart, Histoire des Vdgdtaux Fossiles, 1828-44.
Observations sur la Structure interieure du Sigillaria, etc., in

Archives du Museum, i. 405.

Exposition Chronologique des Periodes de Vdgdtation, in Ann.

des Sc. Nat. 3d series, Bot. xi. 285.
Carruthers, on Gymnospermatous Fruits from the Secondary Kocks of

Britain, Journ. Bot., Jan. 1867.
on the Structure of the Stems of the Arborescent Lycopodiacese

of the Coal Measures, Nos. i. to iv., Month. Microsc. Journ.,

vols. i. ii. iv.
on the Cryptogamic Forests of the Coal Period, Paper read

before the Royal Institution of Great Britain, 16th April 1869.
on the Structure and Affinities of Sigillaria and Allied Genera,

Quart. Journ. Geol. Soc, Aug. 1869.

on a Fossil Cone from the Coal Measures, Geol. Mag., 1865.

on Caulopteris punctata, ihid.

on Araucaria Cones from the Secondary Beds of Britain, ihid.

1866.
■ on an Aroideous Fruit from the Stonesfield Slate, ihid. 1867.

on Cycadoidea Yatesii, ihid. 1867.

on the Structure of the Fruit of Calamites, Journal of Botany,

1867.

on British Fossil Pandanacese, ihid. 1868.

on British Fossil Coniferse, ihid. 1869.

on the Petrified Forest near Cairo, Geol. Mag., vii. 306.

on the Structure of a Fern-Stem from the Lower Eocene,

Journ. Geol. Soc, xxvi. 349.

on the Structure and Affinities of Lepidodendron and Cala-
mites, Trans. Bot. Soc. Edin., viii. 495.

on some Fossil Coniferous Fruits, Geol. Mag., vols. iii. vi.

on Beania, a new genus of Cycadean Fruit, from the York-

shire Oolites, Geol. Mag., vol. vi.
on Plant-remains from the Brazilian Coal-beds, with Remarks

on the genus Flemingites, Geol. Mag., vol. vi.
on the Fossil Cycadaceous Stems from the Secondary Rocks

of Britain, Linn. Trans., xxvi. 675.
on the History and Affinities of the British Coniferse, Brit.

Assoc. Reports, 40th Meeting, p. 71,

LITERATURE OF THE SUBJECT. 107

Carruthers, List of New Genera and Species of Fossil Plants, Nos. i.

ii. and iii., Journal of Botany, vols. viii. ix. x.
Coalfields, by a Traveller under ground.
Corda, Beitrage zur Flora der Vorwelt, Prag. 1845.
Cotta, Dendrolithen, Leipzig, 1850.
Dawson, J. W., on Spore-Cases in Coal, Ann. Nat. Hist., 1871, p.

321.
on Vegetable Structures in Coal, Quart. Journ. Geol. Soc,

1860.
on the Pre-Carboniferous Flora of New Brunswick and Eastern

Canada, Canadian Naturalist, May 1861.
on the Flora of the Devonian Period in North-Eastern

America, Quart. Journ. Geol. Soc, Nov. 1862.
on an Erect Sigillaria and a Carpolite from Nova Scotia,

Quart. Journ. Geol. Soc. Lond.

on Calamites, Ann. Nat. Hist. 4th ser. vol. iv. 272.

on the Varieties and Mode of Preservation of the Fossils

known as Sternbergite, Canadian Naturalist ; also in Edin. New

Phil. Journal, N.S. vii. 140.

Acadian Geology, 1868.

the Fossil Plants of the Devonian and Upper Silurian For-
mations of Canada, Geol. Survey of Canada, 1871.
on the Pre-Carboniferous Floras of North-Eastern America,

with special reference to that of the Erian (Devonian) Period,

Proc. Roy. Soc. Lond., May 5, 1870.
on the Grapliite of the Laurentian Rocks of Canada, Quart.

Journ. Geol. Soc, xxvi. 112.
Dimker, Zettel, and Meyer, Beitrage zur Naturgeschichte der Vorwelt.
Ettingshausen, Beitrage zur Flora der Vorwelt in Abhandlungen der

Geolog. Reichsanstalt, Vienna, 1851.
Forbes, on Tertiaiy Leaf-Beds in the Isle of Mull, discovered by

the Duke of Argyll, F.G.S., with a note on the Vegetable

Remains from Ardtun Head, Quart. Journ. Geol. Soc. Lond.,

vol. vii.
Giebel, Palseontologie.
Goeppert, Beitrage zur Bernsteinflora ; sur la Structure de la Houille.

Die Gattungen der Fossilen Pflanzen, Bonn, 1841.

Monographic des Fossilen Coniferen, 1850.

Systema Filicum Fossilium, Nova Acta, xvii.

Ueber die Fossilen Cycadeen, Breslau, 1844.

Erlauteruns: der Steinkohlen-Formation.

108 PAL^ONTOLOGICAL BOTANY.

Goeppert, Die Fossile Flora der Permischen Formation, Palseonto-

graphica, Hermann von Meyer, Cassel, 1864.

Beitrage zur Kenntniss Fossilen Cycadeen, Breslau.

Grand d'Eiiry, on Calamites and Asterophyllites, Ann. Nat. Hist.,

ser. 4, vol. iv. 124.
Harkness, on Coal, Edin. Phil. Journ., July 1854.
Heer, Flora Tertiaria Helvetise, 3 vols.

Flora Fossilis Arctica, 1868-1871.

on the Fossil Flora of Bovey Tracey, Phil. Trans. R.S.L., 152,

p. 1039.
on the Fossil Flora of North Greenland, Phil. Trans,, vol. 159.,

p. 445.
Hooker, on Some Minute Seed- Vessels (Carpolithes ovulum, Brong-

niart) from the Eocene beds of Lewisham, Proceed. Geol. Soc,

1855.
Vegetation of the Carboniferous Period, in Mem. of Geol.

Survey, ii.

on a New Species of Volkmannia, Quart. Journ. Geol. Soc.

Lond., May 1854.
King, on Sigillaria, etc., in Edin. New Phil. Journal, xxxvi.
Lesquereux, on the Coal Measures of America, Silliman's Journal, 1863.
Lindley and Hutton, Fossil Flora, 3 vols. A revision of the original

work, with a supplementary volume containing the recent addi-
tions, and a Synopsis of the Fossil Plants of Britain by Mr. W.

Carruthers, is announced as about to be published.
Lowry, Table of the Characteristic Fossils of Different Formations.
M'Nab, on the Structure of a Lignite (Paloeojntys) from the Old Red

Sandstone, Trans. Bot. Soc. Edin., x. 312.
Mueller and Smyth, on Some Vegetable Fossils from Victoria, Geol.

Mag., vii. 390.
Meyer, Hermann Von, Palseontographica. Beitrage zur Naturgeschichte

der Vorwelt, 1864.
Nicholson, on the Occurrence of Plants in the Skiddaw Slates, Geol.

Mag., vol. vi.
Paterson, Description of Pothocites Grantoni, a New Fossil Vegetable

from the Coal Formation, Trans. Bot. Soc. Edin., vol. i.
Penny Cyclopaedia, vol. vii.. Coal Plants.
Pictet, Traitd de Pal^ontologie.
Quekett, on the Minute Structure of Torbane Hill Mineral, Journ.

Microsc. Sc, 1854.
Raulin, Flore de I'Europe pendant la Pdriode Tertiaire, in Ann. des Sc.

Nat., 3d ser. x. 193.

LITERATURE OF THE SUBJECT. 109

Redfern, on the Nature of the Torbane Hill and other Varieties of

Coal, Brit. Assoc. Liverpool, 1854.
Roehl, A. von, Fossile Flore der Steinkohlen Formation Westphalens.
Saporta, Etudes sur la Vdgdtation du Sud-Est de la France a I'Epoque

Tertiaire, Annales des Sciences Naturelles, ser. 4, tome xvi. 309,

xvii. 191, xix. 5 ; ser. 5, tome iii. 5, iv. 5.
Schenk, Professor, die Fossile Flore der Nordwest Deutschen Wealden

Formation.
Schimper, Traitd de Paldontologie Vdgdtale, 1870-71.
Tate, on the Fossil Flora of the Mountain Limestone Formation of the

Eastern Borders, in connection with the Natural History of Coal

(in Johnstone's Eastern Borders).
Torbane Coal, as noticed in the Report of the Trial as to the sub-
stance called Torbane Mineral or Torbanite.
linger. Genera et Species Plantarum Fossilium.

Chloris Protogsea.

Le Monde Primitive (a work which contains picturesque views

of the supposed state of the earth at different geological epochs),
on the Flora of the Eocene Epoch, Journ. Bot., iii. 39.

Weber and Wersel, Die Tertiarflore der Nieder Sheinescher Braun-

kohlen Formation.
Williamson, W. C, on the Organisation of the Fossil Plants of the

Coal Measures, Ann. Nat. Hist., 1871, p. 134.
on the Structure and Affinities of the Plants hitherto

known as Sternbergise, Mem. Manch. Lit. and Phil. Soc, ix.
on a New Form of Calamitean Strobilus, from the Lancashire

Coal Measures, Mem. Lit. Phil. Soc. Manchester, vol. iv. 3d

series.
on the Structure of the AVoody Zone of an Undescribed Form

of Calamite, Mem. Lit. Phil. Soc. Manchester, vols. iv. and viii.

3d series.

on Volkmannia Dawsoni, ibid. 1870-71.

on Zamia gigas (Williamsonia gigas), Linn. Trans., xxvi. 663.

—.^—. on the Organisation of Fossil Plants of the Coal Measures,

Part I., Calamites, Phil. Trans. R.S.L., vol. 161, p. 477.
Witham, on the Structure of FossU Vegetables.
Yates, on Zamia gigas. Proceed. Yorkshire Phil. Soc, April 1847.
Young, J., and Armstrong, Jas., on the Carboniferous Fossils of the

West of Scotland, Trans. Geol. Soc. Glas., vol. iii.

Besides geological treatises such as those of Ansted,
Beudant, Jukes, Lyell, and others.

EXPLANATION OF PLATES.

PLATE I.

Fig. 1. Palreopteris Hibernica, Schiinper (Cyclopteris Hibernica,

Forbes). One-sixth the natural size.
Fig. 2. A pinnule somewhat magnified, showing the venation.
Fig. 3. A fertile pinna, natural size.
Fig. 4. Two cup-shaped indusia borne on the rachis.
Fig. 5. Sporangia enclosing spores. From the Coal-measures.
Fig. 6. Sporangia of Hymenophyllum Tuubridgense, Sm. (Fern of

present epoch.)
Fig. 7. Sporangium of Polypodium vulgare, Linn. (Fern of present

epoch.) Figs. 5, 6, and 7, magnified to the same extent.
Fig. 8. Transverse section of Osmundites Dowkeri, Carruthers.
Fig. 9. Two cells of Osmundites, filled, the one with starch granules,
and the other with mycelium of a fungus.

PLATE n.

Fig. 1. Cycadeostrobus ovatus, Carr. From the Wealden, Isle of
Wight.

Fig. 2. Beania gracilis, Carr. From the Yorkshire Oolite.

Fig. 3. Bennettites Saxbyanus, Carr. From the Lower Greensand of
the Isle of Wight.

Fig. 4. Pinites Leckenbyi, Carr. From the Lower Greensand of the
Isle of Wight.

Fig. 5. Trigonocarpon olivseforme, Lindl. and Hutt. From the Coal-
measures, Manchester.

Fig. 6. Trigonocarpon sulcatum, Carr. Coal-measures, Wardie, Edin-
burgh.

Fig 7. Sequoiites Gardner!, Carr. Erom the Gault at Folkestone.

Figs. 8, 9. Cupressinites Thujoides, Bowerbank. From the Eocene
at Sheppey.

Fig. 10. Scale of Ai'aucarites Brodiei, Carr. From the Great Oolite
at Stonesfield.

112 EXPLANATION OF PLATES.

Fig. 11. Scale of Araucarites Pliillipsii, Carr. From the Oolite of
Yorkshire.
All the figures on this Plate (except Fig. 2, which is one-
half of the natural size) are drawn the size of nature.

PLATE III.

Fig. 1. Mass of coal from Fordel, Fifeshire, containing numerous
sporangia of Flemiugites. These sporangia occur in coal
from different localities in England and Scotland. Binney
has seen them in Wigan coal. Huxley has found them
abounding in coal near Bradford (Balfour, R.S.E. Trans.)

Fig. 2. One of the Sporangia entire, and separated from the coal
(Balfour).

Fig. 3. Sporangium with its valves separated, containing a quantity
of black carbonaceous matter in its interior (Balfour).
This matter is formed by the altered spores (microspores).

Fig. 4. Sporangium, showing the triradiate marking on the under sur-
face, and a granulation produced probably by the spores in
the interior.

Fig. 5. Punctated woody tissue (Coniferous). From the needle coal of
Toplitz, Bohemia (Harkness).

Fig. G. Scalariform vessels from coal (Balfour).

Fig. 7. Stigmaria, with markings of rootlets. One showing the
papilla to which the rootlet was articulated (Hooker).

Fig. 8. Transverse section of Stigmaria, showing the vascular cylinder
divided into wedges (Hooker).

Fig. 9. Tissues of Stigmaria, showing the inner portion of the vas-
cular cylinder (Hooker).

Fig. 10. Transverse section of a Lepidostrobus, the fructification of
Lepidodendron, showing scales and sporangia (Hooker).

Fig. 11. Ulodendron Taylori (Carruthers).

PLATE IV.

Fig. 1. Sigillaria Brownii, restored (Dawson).

Fig. 2. Sigillaria clegans, restored (Dawson).

Fig. 3. Lepidodendron, restored (Carruthers, Bot. Soc. Trans.)

Fig. 4. Calamites, restored (Carruthers, Bot. Soc. Trans.)

Fig. 5. Psilophyton, a fossil of the Devonian epoch (Dawson).

Pll

BaJfour's PalaeoTitoIogical Botany.

A.T.HoThctad e'. ViUi

Fossil Ferns

IJtrticra uLk'oKjiTtr -

PI II

-BaIfoij3"'s Paleeontolo^caJ Bol Ajry.

AT Hoi 1; ok dLei e+. iiUi

Minler n Br o » rmp

Fos8ii Cry rnno sperm OILS Fruits

PI. III.

Balfour's Talseontolo^ical Botairy.

J. \^

12.

e "

/ >ni?">%

■" 1 % '
\

^!.

M'Fariajie 8^ Erslune, LitW^Eaui''

Coal ancL Coal-Planis.

PL IV.

Balfo-afs Talaeontological Botany.

Pi

M'^Parlane 8c;'i;Ts;cine, LiWEaiit^

Jjevonian and CarlDOTiiferous Flora.

INDEX.

Abietites, 84, 85, 87.

Acacia, 90, 92.

Acanthocarpum, 72.

Acer, 92, 97.

Acerites, 87.

Acrogens of present day, 26.

Acrogens, fossil, reign of, 25, 26.

Adiantites, 41.

iEthophyllum, 79.

Alder, 94.

Aletliopteris, 43, 72.

Algfe, 35.

Algse of Cretaceous epocli, 87.

Alnites, 87, 94.

Alnus, 94, 97.

Alsopliila, 29.

Amber, 90.

Amber flora, Goeppert on the, 91.

Amentiferse, fossil, 92.

Ancestropbyllum, 48.

Andromeda, 96, 97.

Angiosperms, fossil, reign of, 25, 87.

Annularia, 61, 71.

Anomopteris, 79.

Anona, 97.

Antliodiopsis, 72.

Antliolithes, 64.

Anthracite, 36.

Apocynacese, fossil, 92.

Araucaria, 5, 6, 7, 85, 90.

Arancarioxylon, structure of, 63.

Araucarites, 82, 83, 84, 85, 86, 87.

Arctic fossil flora (Miocene), 97.

Ai-ctic Regions, Palseozoic flora of, 40.

Arctic Regions, fossU wood of, 95.

Arthropitys, 72.

Artisia, 64.
Aspleuium, 28.
Asterophyllites, 35, 61, 71.

Bambusium, 92.

Bauhinia, 90, 92.

Beania, 82.

Bear Island, fossil flora of, 40, 59.

Beeches, 97.

Bennettitese, 86.

Bennettites, 85, 87.

Betula, 94, 97.

Bothrodendron, 57.

Bovey Tracey flora, 96.

Bovey Tracey, Devonshire, lignite

beds of,. 96.
Brachyphyllura, 80, 86, 87.
Bryson's instrument for slitting, 14.
Bucklandia, 84, 86.

Csesalpinia, 90.

Cainozoic period, fossil plants of, 87.

Calamites, 35, 41, 53.

Calamites, foliage and fruit (woodcut),

62.
Calamites, structure of, 57.
' Calamites, structure of fruit, 60.
Calamodendron, 59, 72.
Callipteris, 72.
Callitris, 90.
Camptopteris, 79, 80.
Carboniferous epoch, 36.
Carboniferous vegetation, its general

character, 69.
Carbonisation, 9.
Cardiocarpum, 41, 72, 78.

114

INDEX.

Cardiocarpum, structure of, 64.

Cardiopteris, 40.

Carpinites, 87.

Carpinus, 94.

Carpolitlies, 78, 83, 92, 97.

Cassia, 90.

Casts of plants, 8.

Casuarina, 90.

Caulinites, 90.

Caulopteris, 43,

Centrolobium, 90.

Chalk flora, characteristics of, 87.

Chara, 92.

Characeae, fossil, 91.

Chondrites, 87.

Cinchonacere, fossil, 92.

Cinnamomum, 96.

Classes to which fossil ]plants belong,

2.
Climate as determined by fossil plants,

19.
Climate of the Tertiary period, 100.
Club-mosses, 26, 30.
Coal-basins, 37.
Coal, brown, structure of, 100.
Coal, Fordel, 36, 56.
Coal-formation, extent of, 38.
Coal, household, 36.
Coal-measures, flora of, 39.
Coal, parrot, 36.

Coal-plants, in situ, or drifted, 67.
Coal, structure in, 36.
Coal, Wigan cannel, 36.
Coal of Oolitic epoch, 82.
Coal of Tertiary beds, 100.
Combretacese, fossil, 92.
Comptonia, 92, 94.
Comptonites, 87.
Cones, fossil, of Wealden, 85.
Confervites, 87.
Coniferae, 87.
Coniferse, modern, 72.
Coniferae, number of Miocene species,

97.
Coniferae, Oolitic, 80.
Coniferae, structure of recent, 74.
Coniferae of brown coal deposits,

100.
Coniferae of Miocene Arctic fossil

flora, 97.

Coniferae of Secondary strata, 85.

Coniferae of Tertiary period, 89.

Coniferous genera ot Lias, 79.

Coniferous vegetation of Upper Cre^
taceous period, appearance of, 89.

Copaifera, 90.

Cordaites, 35, 72.

Cornus, 97.

Corylus, 96, 97.

Crataegus, 97.

Credneria, 87.

Crematopteris, 79.

Cretaceous system, fossil plants of,
87.

Crossozamia, 86.

Cryptogamia, number of Miocene
species of, 97.

Cryptomeria, 87.

Cryptomerites, 86.

Ctenis, 78, 79.

Cucumites, 90.

Cunninghamites, 87.

Cupressineae, 89.

Cupressoxylon, 93.

Cyathea, 29.

Cyatheites, 72.

Cycadaceae, 87.

Cycadaceae, fossil, Carruthers' arrange-
ment of, 86.

Cycadaceae, modern, 72, 75.

Cycadaceae, Oolitic, 80.

Cycadaceae in Mesozoic period, 77.

Cycadaceae of Lias, 79.

Cycadaceae of Tertiary period, 89.

Cycadaceae of Wealden epoch, 84.

Cycadeostrobus, 85.

Cycadites, 44, 79, 84, 87.

Cycadoidea, 83.

Cycas, 76.

Cyclopteris, 32, 35, 43, 72.

Cyclostigma, 41.

Cyperites, 48.

Cystoseirites, 87.

Dadoxylon, 35, 63.
Dalbergia, 90.
Dammarites, 87.
Daphnogene, 92, 96, 97.
Dawson on Devonian fossils, 35.
Desmodophyllum, 92.

INDEX.

115

Dicotyledons of Pliocene epoch, 98.
Dictyotlialamus, 72.
Didymophyllum, 48.
Didymosorus, 95.
Dioonopteris, 72.
Dirt-bed, Portland, 83.
Dolichites, 92.
Drepanocarpus, 90.
Dryandroides, 96.

Echitonium, 92, 96.
Encephalartos, 76.
Entada, 90.

Eocene epoch, Algfe of, 90.
Eocene epoch, characteristics of, 90.
Eocene epoch, Coniferse of, 90, 91.
Eocene epoch, flora of, 89, 90.
Eocene epoch, fruits of, 90.
Eozoon Canadense, 31.
Eqiiisetacese, 29, 59.
Equisetites, 71.
Equisetum, 31, 53, 79, 94, 95.
Equisetum spores, 32.
Equisetum, structure of fruit, 60.
Erian fossil plants, 35.
Erythrina, 92.

Exogenous trees of Carboniferous epoch,
62.

Fagus, 94, 97.
Eavularia, 46.
Fern -flora in connection with climate,

41.
Ferns, 96.

Ferns, structure of, 29.
Ferns of Carboniferous strata, 41.
Ferns of present day, 26.
Ficus, 96.
Fig, evergreen, 96.
Filicites, 94.
Fittonia, 86, 87.
Flabellaria, 64, 87.
Flemingites, 51, 52, 57.
Floras of present day in connection

with fossil plants, 19.
Folliculites, 92.
Fossil botany, recapitulation of chief

points connected with, 103,
Fossil botany, list of works treating

of, 105.

Fossil plants compared with modern

plants, 3, 4.
Fossil plants, determination of, 3.
Fossil plants, mode of preservation of,

8.
Fossil plants, number of, 23.
Fossiliferous periods, according to

Brongniart, 25.
Fossiliferous rocks, 20.
Fructification in ferns of Carboniferous

epoch, 40.
Fruits, fossil, of Isle of Sheppey, 90.
Fungi, fossil, 91.

Gardenia, 97.

Gault, Coniferje of, 80, 85,

Getonia, 92.

Glyptostrobus, 97.

Gres bigarre, 78,

Gymnosperms, fossil, reign of, 25.

Gyrogonites, 92.

Haidingera, 78.

Hakea, 97.

Halonia, 57.

Heer's list of plants from the Bovey

Tracey Miocene formation, 96.
Heer on the migration of plants, 98.
Heer on the number of species in the

Arctic fossil flora, 97.
Heer's remarks on the Polar flora,

98.
Hightea, 90.
Horse-tails, 29.
Huttonia, 71,
HjTnenophylleae, 34,
H}Tiienophyllites, 71.
Hymenopliyllum, 35,

Ilex, 97.
Infiltration, 9.
Inga, 90.

Isoetes, 27, 49, 89.
Ivy, 97.

Juglandites, 87.

Jurassic period of Brongniart, 79.

Kaidacarpum, 84.
Keupric period, 79.

116

INDEX.

Kimmeridge Clay, Coniferse of, 85,
Knorria, 41, 48, 57.
Knorria, pliyllotaxis of, 55.

Lastrea, 29.

Lauracese, 97.

Lauracese, fossil, 92.

Laurel, 96.

Laurentian rocks, 31.

Laurus, 92, 96.

Leaf-beds of Ardtun, Mull, 93.

Leaf-beds of Bournemouth, 95.

Leaf -beds, geuera of, 94.

Leguminosae, fossil, 92.

Leguminosites, 90.

Lepidodendron, 35, 41, 49.

Lepidodendron, pliyllotaxis of, 54.

Lepidophloios, 57.

Lepidopliyllum, 41, 56.

Lepidostrobus, 35, 50, 52.

Lias, Coniferse of, 80,

Lias, fossil plants of, 79 ,

Libocedrus, 90.

Lignite, 32.

Lignite beds of Bovey Tracey, 96.

Lignites, 9.

Lonchopteris, 43, 84.

Lough Neagli, Miocene formation of, 93.

Lower Greensand, cone of, 89.

Lower Greensand, Coniferse of, 85.

Lycopodiacese, 49, 54.

Lycopodiacese, modern, 26.

Lycopodites, 56.

Lycopodium, 30, 53.

MacClintockia, 97.

Macrospores, 30.

Magnolia, 97.

Mantellia, 83, 84, 86.

Marsilea, 31, 33.

Marsileaceee, 31.

Mesozoic period, flora of the, 72.

Microspores, 30.

Microzamia, 87.

Mimosa, 90.

Mimosites, 92.

Miocene epoch, flora of, 89, 92.

Miocene period, temperature of, 97.

Mull, leaf-beds of, 93.

Mull, Miocene formation of, 93.

Munsteria, 87.
Myrica, 94, 97.

Naiadaceae, 87.

Natural orders to which fossil plants

belong, 22.
Neuropteridese, 41.
Neuropteris, 42, 71.
Nicolia, 11.

Nicol's mode of preparing sections, 13.
Nilssonia, 79.
Nipadites, 90.
Noeggerathia, 64, 71, 72.
NjTnphsea, 97.

Odontopteris, 42, 72.

Oolitic epoch, flora of, 80.

Oolite, fruits of, 83.

Oolite, Inferior, Coniferse of, 86.

Oolite, Lower, 82.

Oolite, Scottish, plants of, 81.

Oolite, Upper, 82.

Oolite, Yorkshire, 83.

Osmunda, 89.

Osmundites, 91.

Otopteryx, 97.

Otozamites, 79.

Oxford Clay, Coniferse of, 86.

Paleeophytology, 1.
Palseopitys, 32.
Palseopteris, 32, 34, 41.
Palseozamia, 79.

Palaeozoic or Primary period, 26.
Palseozoology, 1.
Palissya, 80, 86.
Paliurus, 97.
Palm, 96.

Palmacites, 87, 90, 96.
Pandanacese, 84.
Pecopteris, 42, 96.
Pecopteridese, 41.
Pepperworts, 31.
Permian flora, 71.
Permian period, fruits of, 72.
Petrifaction, 9.
Petrified forests, 11.
Pence, 64, 80, 82, 86, 89.
Phanerogamia, number of Miocene
species of, 97.

INDEX.

117

Phaseolites, 92.

Phoenicites, 92.

Phyllotaxis, 54, 55.

Pilularia, 31.

Pinites, 78, 85, 86, 87, 89, 100.

Pinites, structure of, 63.

Pinus, 86, 94, 97.

Pissadendron, 63,

Pitus, structure of, 64.

Plane, 94.

Platanites, 94.

Platanus, 97.

Pliocene epoch, flora of the, 89, 98.

Plumiera, 92,

Podocarpus, 90.

Podocarya, 84,

Portland beds, 82.

Portland Crag, 82.

Portland stone, Coniferse of, 85,

Pothocites, 66.

Proteacese, fossil, 92, 97.

Protopteris, 87.

Prototaxites, 35,

Prunus, 97.

Psaronius, 44, 71.

Psilophyton, 35.

Pterocarpus, 90.

Pteroiihyllum, 84, 79,

Purbeck, Coniferse of, 85.

Purbeck period, 83.

Quercus, 94, 96, 97.

Raulin on the Tertiary flora of Central

Eui'ope, 99.
Raumeria, 86,
Recapitulation of chief points connected

with fossil botany, 103.
Rhabdocarpum, 72, 77.
Rhamnites, 94, 95.
Rhamnus, 94, 97.
Rhizocarj)e8e, 31.
Rings, number of annual, in fossil

Exogens, 100.

Sagenopteris, 71, 79,
Salicites, 87.
Salix, 97.
Sargassites, 87.
Scalariform vessels, 30.

Schizopteris, 43.

Secondary period, flora of the, 72.

Sections of fossils for microscope

12,
Selaginella, 27, 51, 53.
Selaginites, 35.
Senftenbergia, 40.
Sequoia, 87, 96, 97.
Sequoiites, 85, 89,
Shale, 37.

Sheppey, fruits of Isle of, 90.
Sigillaria, 45.
Silicified stems, 10.
Sphenophyllum, 35, 61.
Sphenopteridese, 41.
Sphenopteris, 34, 41, 42.
Sporangia, 30, 56.
Stangeria, 78.
Steinhauera, 92.
Sternbergia, 64, 97.
Stigmaria, 41, 47, 48.
Stonesfield slate, 82.
Stratified rocks, 21,
Structure of fossil plants, 12.

Table of formations, 21.

Taxites, 86, 94, 95, 100.

Taxodieai, 89.

Taxodites, 79, 80, 94, 95.

Taxodium, 97.

Terminalia, 92.

Tertiary flora of Europe, 99.

Tertiary period^ characteristics of, 89,
100.

Tertiary period, fossil plants of, 87.

Tertiary vegetation, Brongniart's divi-
sions of, 89.

Thaumatopteris, 80.

Thuites, 81, 85, 86.

^Thnjopsis, 97.

Tilia, 97.

Trap rocks, 20.

Tree fern, 27.

Trees of Miocene Arctic fossil flora
97.

Triassic fossils, 77.

Trigonocarpum, 64, 72.

Triplosporites, 50, 53.

TuflF-beds, 94.

Tulip tree, 97.

118

INDEX.

Ulmus, 92.

Ulodendroii, 57.

Underclay, 37. '

Unger's list of genera of Eocene epocli,

90.
Upper Chalk, 85.
Upper Greensand, Coniferse of, 85.

Vaccinium, 96.'

Vitis, 96.

Yolkmannia, 60.

Voltzia, 78, 79.

Vosgesian period, Brongniart's, 78.

Walchia, 71.
Walnuts, 97.
Wealden, Coniferse of, 85.

"Wealden epocli, flora of, 84.
Widdringtonites, 87.
Williamsonia, 81.
Willianisonieae, 86.
Willow, 97.

Works, list of, treating of fossil botany,
105.

Yatesia, 86.
Yew, 94.

Zamia, 78.
Zamiepe, 86.
Zamiostrobus, 78.
Zamites, 78, 79, 84, 87. ^
Zostera, 32.
Zosterites, 87.

THE END.

Pritttedby R. & R. Clark, Edinburgh.

PROFESSOR BALFOUR'S
BOTANY.

In one vol., royal 8vo, pp. 1117, with 1800 Illustrations,

price 21s.,

CLASS-BOOK OF BOTANY.

Being an Introduction to the Study of the VegetaUe Kingdom.
By J. HUTT0:N' BALFOUE, M.D., F.K.S.,

Professor of Medicine and Botany in the University of Edinburgh, Regius Keeper
of the Royal Botanic Garden, and Queen's Botanist for Scotland.

{May also he had in two Parts^ price 21s.)

" In Dr. Balfour's ' Class-Book of Botany,' the author seems to have
exhausted every attainable source of information. Few, if any, works on
this subject contain such a mass of carefully collected and condensed
matter, and certainly none are more copiously or better illustrated." —
Hooker^ s Journal of Botany.

" Professor Balfour's ' Class Book of Botany ' is too well and favourably
known to botanists, whether teachers or learners, to require any introduc-
tion to our readers. It is, as far as we know, the only work which a
lecturer can take in his hand as a safe text-book for the whole of such a
course as is required to prepare students for our University or medical
examinations. Every branch of botany, structural and morphological,
physiological, systematic, geographical, and pala^ontological, is treated in
so exhaustive a manner, as to leave little to be desired.

" The work is one indispensable to the class-room, and should be in the
hands of every teacher." — Nature,

" The voluminous and profusely illustrated work of Dr. Balfour is too
well known to need any words of comment." — Lancet.

EDINBURGH : ADAM AND CHARLES BLACK.

JUKES' GEOLOGY.

Just Published, in crown 8vo, clotla, price 12s. 6d,,
NEW EDITION OF BEETE JUKES'

MANUAL OF GEOLOGY.

THIRD EDITION.
Illustrated with numerous Woodcuts.

Edited by AECHIBALD GEIKIE, F.E.S,

Professor of Geology and Mineralogy in tlie University of Edinburgh, and
Director of the Geological Survey of Scotland.

"A book which every earnest student of geology will welcome with
delight, and than which he can find no better guide to his studies." —
Edinburgh Courant.

OWEN'S PALEONTOLOGY

Second Edition, 8vo, illustrated^ price 7s. 6d.

PAL/EONTOLOGY,

OR

A SYSTEMATIC SUMMARY OF EXTINCT ANIMALS
AND TEEIB GEOLOGICAL RELATIONS

By KICHAED OWEN, E.E.S.,

Superintendent of the Natural History Department in the
British Museum.

"The Prince of Pala3ontologists has here presented us with a most
comprehensive survey of the characters, succession, geological position, and
geographical distribution of the various forms of life that have passed
away." — Medical Times and Gazette.

EDINBUEGH : ADAM AND CHAELES BLACK.