39. Along with the Pezizae and Sphceriae and
those allied genera which resemble them
in producing their spores enclosed in thecae,
there are other forms also included in the
227
Pyrenomycetes and Discomycetes, which,
while they resemble those last named in th e
general outline and structure of their recep-
tacles, differ from them completely in the
mode of origin of the spores. The simulta-
neous occurrence of some of these forms,
along with their ascophorous analogues, or,
in other instances, the successive develop-
ment of both kinds of receptacles in the
same position, had been frequently observed,
and had given rise in the minds of some my-
cologists to the suspicion of the existence of
a relation more close than was generally ad-
mitted. This suspicion did not, however,
take a sufficiently distinct form to lead to
observation until the MM. Tulasne, in a
series of researches scarcely completed, showed
that the genera in question, hitherto con-
sidered as distinct, were in fact identical, and
that receptacles containing thecae and para-
physes, are produced on the same stroma, or,
in other words, on the same individual plant,
as those which contain acrogenous spores.
40. The earliest researches of MM. Tulasne*
were directed to the Pyrenomycetes. In some
species of Sphceria, they found not only that
the same stroma produces receptacles with
acrogenous spores, which are followed by
others bearing thecae; but that, under cer-
tain circumstances, it may give rise to spore-
bearing organs, of a much simpler character;
viz. branching filamentous pedicles, bearing
at their terminations single spores, and rising
directly from the mycelium filaments, with
which they are continuous. In this condition
the plant cannot be distinguished from a
thread Fungus, and has been hitherto described
as such.
41. The later observations of MM. Tulasne f
which are much more in detail, refer almost
entirely to Discomycetes. In a species of
Rhytisma, a genus of Discomycetes, which
inhabits the epidermis of the leaves of plants,
the stroma at first presents the appearance of
a black spot of various extent on the surface
of the leaf. In the substance of this stroma
the first receptacles are formed ; they are
cushion-shaped capsules, furnished with api-
cial apertures, like those of Sphoeria, and are
entirely occupied by a pulpy nucleus, which con-
sists of slender branched filaments, often so long
as to project considerably beyond the aperture.
These filaments bear at their extremities
innumerable minute linear sporules, which
are enveloped in an abundant mucilage, and
are expelled from the ripe capsules in the
form of a long cirrhus. After the capsules
which are developed during the early summer
months have discharged their contents, they
are succeeded by the lirelliform discs of the
perfect Rhytisma. These do not arrive at
maturity until the following spring, and bear
* Notes sur 1'Appareil reproducteur dans lea
Lichens et les Champignons, Ann. des Sc. Xat. 3me.
S. t. xv. p. 370.
f Nouvelles Recherches, &c. Coraptes rendus,
Seance du 13 Dec. 1852.
Q 2
REPRODUCTION, VEGETABLE (VEGETABLE OVUM).
228
upon their upper surface thecae and paraphyses
like those of a Peziza. In other genera
MM. Tulasne found that the ascophorous
receptacles are preceded by capsules which
produce, instead of the linear sporules above
mentioned, cylindrical spores of a much larger
size, each of which is supported at the
extremity of a pedicle of its own.
42. Thus in the plants under consideration
we find that, without counting the sporules
which are produced by filaments rising directly
from the stroma, there are no less than three
varieties of spore-like structures which can
be easily distinguished from each other. All
of these may be produced upon the same,
individual, and one instance is recorded
in which a cupule of a Peziza was found,
which bore among the normal thecae, para-
physes with innumerable, slender, linear
sporules at their extremities. As has been
already hinted, the capsules which contain
acrogenous spores, have been hitherto con-
sidered as belonging to genera distinct from
those represented by the ascophorous recep-
tacles with which they were found associated.
The genus Cytispora is characterised by a
structure which corresponds completely
with that of the capsules described above
in Rhytisma ; and other genera as e. g.
Sporocadus have a similar relation to the
capsules, containing the larger variety of
pedunculated, cylindrical spores.
43. In order to facilitate the description of
these various structures, a nomenclature has
been devised by MM. Tulasne, which may
be adopted with advantage. The minute,
linear sporules, which are produced at the
extremities of branched filaments, like the
paraphyses of Sphaeria, are called spermatia.
The cylindrical bodies of much larger size,
which are borne each at the extremity of a
stipitiform cell, are named stylospores ; while
the term spope is reserved to those which are
formed in the interior of a theca.
43. big. In a third " Memoire " which has
appeared since the above paragraphs went to
press, MM. Tulasne have further prosecuted
their researches on this interesting subject.
The following is an abstract of their account
of the development of a Pyrenomyces (Ce-
nangium), which inhabits the bark of dead
branches of the black alder (Rhamnus Fran-
gula). The plant, in its natural position, is
represented inj^g. 148. The mycelium ramifies,
in all directions, in the substance of the inner
bark of the dead branch. From its filaments
there spring, at irregular intervals, the re-
ceptacles, which as they develope, burst
through the outer bark and epidermis and
exhibit the various forms represented. The
simplest variety( fig. 148. a) resembles in struc-
ture the organ described in 49. as occurring
in Scutula. In form, it is rounded, but at
the same time somewhat conical. The stylo-
spores (Jig. 149. a) which it contains, are
Fig. 149.
a, group of stylospores, with a fragment of the wall
of the receptacle in which they are enclosed;
b, similar group of spermatia. About 300 diarn.
curved, crescentic bodies, supported on pedi-
cles, which have an arrangement perfectly
similar to that observed in Scutula. The
receptacles or cupules in which thecae are
produced are deserving of great attention.
In the early condition, their form is cyathoid
(fig. 148. c), and they resemble those de-
scribed (41.) in Rhytisma. They contain at
this time, innumerable spermatia (fg. 149. 6),
these being supported on filaments which
spring from the inner surface of the cup, as
well as of its margin. As the organ grows,
it expands, and finally becomes discoid
(fig. 148. b}, when it possesses the structure
Fig. 150.
Fig. 148.
Part of a dead branch of Rhamnus Frangula, with Vertical section of discoid receptacle of Cenangium,
receptacles of Cenangium. (Slightly magnified) about 300 diam.
REPRODUCTION, VEGETABLE (VEGETABLE OVUM).
229
represented in Jig. 150. The central portion
of the disc is lined by an ascophorous mem-
brane. The overhanging marginal fold still
exhibits the filaments bearing spermatia, which
characterised the earlier condition of the
receptacle. Our authors are inclined to admit
that the spermatia are to be considered as a
male product, and the whole organ as analo-
gous to a hermaphrodite inflorescence. The
relative positions of the spermatia and thecae
seem admirably adapted to insure their con-
tact with each other.
44. We now pass to the Lichens, with re-
spect to which the greater part of our informa-
tion is again owing to the researches of MM.
Tulasne.* In these plants, as in the Fungi, the
germination of the spore consists in the
emission of a hollow filament from some part
of its surface. This filament which is simply an
extension of the spore-membrane, branches
repeatedly and spreads over the surface, on
which the spore has been sown ; at the
same time it divides by numerous septa,
which occur at irregular intervals. By the
intertwining of the resulting ramifications, a
stroma is formed, to which the term hypo-
thallus is applied, and which constitutes the
vegetative system of the future lichen. So
far the development is the same as the Fungi.
At a longer or shorter period after the forma-
tion of the hypothallus, we begin to observe
upon its surface a whitish layer of spheroidal
cellules, intimately united with each other, as
well as with the filaments from which they
take their origin. This layer serves as the
groundwork for a second formation of glo-
bular cells. These are distinguished from their
predecessors, as well by the regularity of their
form, as by the granules of chlorophylle
which they contain. They are called gonidia,
and are peculiar to the Lichens, among which
their occurrence is almost constant.
45. Such is the origin of the thallus, which,
although, at first sight, it appears to consti-
tute the whole plant, forms only a part, and
that not the most essential part of its vege-
tative system. In the Verrucariae, the most
simply organised Lichens with which we are
acquainted, it does not attain to any higher
development than that above described.
The receptacles (apothecia), which closely
resemble those of a Sphoeria, are formed
upon the surface of the hypothallus, which can
only be distinguished from the stroma of
the Fungus by the presence of scattered col-
lections of gonidia. In the more complicated
fpliaceous Lichens, such as Parmelia, the
mature thallus is formed of two kinds of
tissues, the medullary and the cortical. The
cortical tissue forms two layers an inferior
and superior and consists of thick-walled
cells intimately adherent to each other, and
resembling those of analogous structure,
which so often form the peridia of the higher
* Mem. pour servir a 1'Histoire organographique
et phvsiologique des Lichens, Ann. des Sc Xat.
3me s" t. xvii. pp. 5. and 173.
Fungi. From the surface of the inferior layer
are given off numerous laminar root-like
Fig. 151.
Vertical section of the apothecium of a Lichen (Par-
melia aipolia) and of the subjacent tissue of the
thallus, 200 diam.
a, Lamina proligera, consisting of thecae and para-
physes ; 6, tissue of thick- walled cells continuous
with the cortical tissue of the thallus. Subjacent
to this, but separated by an irregular line of
gonidia, is the medullary" filamentous layer.
appendages: The medullary substance con-
sists of a filamentous central layer, the
elements of which resemble those of the
hypothallus, and are directly continuous with
them ; on either side of this layer, between
it and the cortex, or rather embedded in its
substance, are the gonidia, which form a green
tissue, distinguishable by the naked eye.
To these a special function is assigned, which
shall be noticed at the conclusion of the
article under the head of Gemmation.
46. We have next to describe the recepta-
cles, within or upon which the spores or spore-
like organs (spermatia and stylospores) are
produced. Of these there are three varieties,
to which the terms apothecia, spermogonite,
and pycnides, have been applied. The most
common form of the apothecium is that of a
disc, which may be plane, convex or cup-
shaped. This form is that which charac-
terises the gymnocarpons Lichens. In the
Angiocarpea, the organ is closed upwards,
its superior surface becoming internal, so as
to form a conceptacle like that of the Pyreno-
mycetes, the form of which is subject to
considerable variation. In either case, it is
composed of two layers, the inferior or ex-
ternal, being formed of thick-walled cells
which are soldered together, and resemble
those of the epidermal layers of the thallus.
The superior or internal layer is called the
lanwia proligera. It is formed of two kinds
Q 3
230
REPRODUCTION, VEGETABLE (VEGETABLE OVUM).
of elements : first, the paraphyses, which are
linear, claviform filaments, composed of from
Fig. 152.
Section of fruitful ihallus of Sticta pulmonacea,
about 20 diam.
a, discoid apothecium. The vertical lines indicate
the lamina proligera ; s, spermogonia containing
spermatia ; i, empty spermogonia.
six to eight cylindrical cells, joined end to
end; and secondly, the thecce, which are
obovate vesicles, each containing, almost in-
variably, eight spores. These elements are
arranged side by side, their long diameters
being perpendicular to the surface of the
apothecium. They appear to be glued toge-
ther, even in the fully formed apothecia, by
an intermediary gelatinous substance, which,
however, there is good reason for supposing
to be nothing more than a thickening of
the external membrane, from which it cannot
be distinguished, either in respect of its
chemical or other characters. Iodine colours
this substance, as well as the external mem-
branes of thecae and paraphyses, blue,
without the addition of sulphuric acid. In
the early condition, the cavities of the thecae
are occupied by a yellow, plastic material,
out of which the spores are afterwards formed.
The thickness of the external starchy mem-
brane is at this period relatively more consi-
derable than later; as the spores increase
in size, it gradually diminishes. The struc-
ture of the fully formed spore is best ob-
served in those species in which it is largest.
The spore-membrane, of considerable pro-
portional thickness, is smooth and semi-
transparent, wholly unaltered by iodine and
sulphuric acid. The contents consist partly
of mucous granules, which are coloured
brown by iodine, partly of yellowish oil
globules. The whole is usually invested, even
after its escape from the theca, with the
still adherent remains of the inner proto-
plasmic layer, by which it was immediately
surrounded. In form, the spores are most
frequently ellipsoid and unilocular. In other
instances, however, they are divided by one
or more partitions. This division is either
complete, so that the spore resembles two
obovate cells joined by their larger ends ; or
incomplete, the septa being in some cases
scarcely distinguishable from the protoplasmic
contents of the central cavity.
47. The spores are discharged from the
thecae with an elastic force often sufficient to
project them to a considerable height above
the surface of the apothecium ; a fact, which
M. Tulasne seems to have shown to be
dependent on the great capability of imbibing
moisture possessed by the lamina proligera,
which much exceeds that of the tissue imme-
diately subjacent. It resembles altogether
what is observed in the Pezizas, whose spores,
it is well known, are projected with such
force as to form a cloud above the receptacle.
48. We have next to notice the remarkable
organs which Itzigsohn* described as the
antheridia of the Lichens, and to which he was
the first to assign a distinct function. They
had been previously adverted to by several
botanists, and had been usually considered as
parasitical Pyrenomycetes, which they closely
resemble. They consist of conceptacles em -
bedded below the upper surface of the thallus ;
their presence is revealed by the appearance
of blackish, projecting points, scattered at
irregular intervals. The form of these organs,
Spermogonia of Scutula Wattrothii, 150 diam.
The spermatia are seen escaping in numbers
from the apicial aperture of the organ.
which MM. Tulasne have named spermo-
goniae, is globular, ellipsoid, or oblong. Their
external envelope is frequently hard and
crustaceous, and usually blackish. The cavity
may be simple or multiple ; in the latter case
all the compartments or sinuses open at one
ostiole. The whole of the cavity is occupied by
a filamentous tissue, which consists of two
elements viz., spermatia and the organs on
which they are supported. The latter are
simple or branched filaments, which are usu-
ally undivided, but occasionally jointed. They
originate from the inner surface of the con-
ceptacles. At their summits and articulations,
they bear the spermatia, which are straight or
curved linear organs of great tenuity, and
are motionless. They are coloured brown by
iodine ; both the spermatia and filaments are
embedded in an abundant mucilage ; many of
the former are sterile, and are so long that
they project beyond the opening of the con-
ceptacle like a kind of cirrhus. The whole
structure corresponds in every respect with
that of the spermatia-bearing conceptacles of
the Discomycetes and Pyrenomycetes.
49. To a third variety of conceptacle, MM.
Tulasne have assigned the title of pycnidis,
This organ, although it has only been ob-
served in two genera, Abrothallus and Scutula,
* Bot. Zeitung. 1850. S. 913.
REPRODUCTION, VEGETABLE (VEGETABLE OVUM).
is no less important, as forming another con-
necting link between the Lichens and Fungi.
The special characteristic of these organs is
to be found in their containing, instead of
thecae or paraphyses, stylospores, supported
on stipitiform pedicles or basidia. In their
Pycnidis of the same, about 150 diam.
The stylospores are escaping from the upper ori-
fice of the organ. (The figures from 143 to 154 in-
clusive, are after Tuiasne.)
general form they resemble the spennogoniae,
but their walls are thicker.and they are larger.
Like them they are provided with a vertical
ostiole. The stylospores are oblong, cylin-
drical bodies, more than twice the length of
the spermatia (from -^^ to -^^ f an inch),
obtuse at both ends, very slightly curved,
colourless, and containing only granular pro-
toplasma. They are supported on pedicles,
which have the same arrangements as in the
spermogoniae. They are simple, linear tubular
filaments, which taper towards their extre-
mities. Just as the spermogoniae correspond to
the spermatium-bearing organs of the Fungi,
the pycnides correspond to those receptacles,
containing stylospores, which we have had
occasion to describe both in the Discomycetes
and Pyrenomycetes.
50. Summary. The reproductive organs of
the Fungi and Lichens are of five kinds :
1. Sporules, which are formed by the con-
striction and subsequent separation of the
extremity of a simple cylindrical filament ; 2.
Spermatia with their supporting pedicles ; 3.
Stylospores, with their styles ; 4. Thecae or
asci; o. Basidia, with their basidiospores.
Of these the last mentioned are to be found
only, as we know at present, in Fungi which
are provided with no other reproductive organ.
The first four, on the other hand, all of them
occur in plants belonging to one family of
Fungi viz. the Disco- and Pjreno-mycetes :
they also all occur, with the exception of
the first, among the Lichens. They may be
arranged, as regards the complexity of their
form and structure, in the order in which they
231
are placed above, the simple acrogenous
sporule standing first. A similar arrangement
may also be adopted in the description of the
corresponding varieties in the reproductive
phenomena which manifest themselves in con-
nection with each variety of spore-like body.
As regards the first of these, nothing further
need be said, as the formation of the sporule
by division, as described above, constitutes
the whole reproductive process. It is exem-
plified in the stroma of a Sphoeria, when in
a condition corresponding to that which cha-
racterises a Melanconium. The spermatium
is found only in a special receptacle, the
general form and structure of which remain
always the same, as in the Cytispora-like
capsule of the Disco- and Pyreno-mycetes
and the spermogoniae of the Lichens. The
stylospores are also formed in special organs
(pycnides, and the corresponding organs
among the Fungi), which differ from the last
only as regards the structure of the parts
upon which the spore is immediately sup-
ported. Lastly, the receptacles which bear
thecae are of larger size, more complicated
in their structure, and later in making their
appearance than any of the rest, as in the
instance of the disc of Peziza, the closed re-
ceptacle of Sphceria, and the apothecium of
the Lichens.
51. The Pyreno- and Disco-mycetes are, as
we have seen, so closely allied to the Lichens
as regards their reproductive organs, that the
characters of the two families seem in this
respect to merge into each other. The dis-
tinction is to be sought in the vegetative
system. The thallus of the Lichen differs
from the thallus-like stroma of the Fungus in
its possessing two additional elements, the
cortical layer and the gonidia. We observe
their first appearance in the mosc simple form
in Verrucaria.
52. There is as yet no sufficient ground for
definitively concluding that the reproductive
functions of the asci and spermatia are com-
plementary to each other ; or, in other words,
that these organs are sexual. There is, how-
ever, good reason for considering it probable;
first, because, when spermatia and asci are
produced on the same mycelium, the former
always precede the latter in their develop-
ment by a considerable period, just as among
the higher Cryptogamia, the antheridia precede
the archegonia ; and, secondly, because the
organs on which the spermatia are supported,
and the asci, stand in an anatomical relation
to each other, and to the receptacle within
or upon which they are formed, which closely
resembles those of the antheridia and epispores
of the Fuci, or of the antheridia and tetraspores
of the Florideae. We are well aware that
these analogies do not afford the slightest
proof of an actual correspondence between
the organs in question. All more direct
evidence, however, is absent ; no observations
have been made to show that the spermatia or
stylospores exercise any influence on the thecae
or their contents, and on these important
points, therefore, we must look to further ob-
Q4
232
REPRODUCTION, VEGETABLE (VEGETABLE OVUM).
servations for the grounds on which an opinion
may be formed.
53. The fifth and last variety of reproductive
organ mentioned above, is the basidium.
The Mushrooms, along with another group of
Fungi, which is distinguished by the possession
of loculate receptacles, each loculus of which
is lined with a hymenium, as e.g. Lycoperdon,
include nearly all of the genera in which it
occurs, and form Leveille's order, Basidio-
sporea3. The order is a very natural one,
and between it, and any of those which are
most closely related to it, we can find no
intermediate forms which at present might
serve as guides in comparing the reproductive
organs of the one with those of the other.
The basfdiospore is distinguished from all the
other acrogenous forms (stylospores, sper-
matia), by well-marked and easily-defined
characters viz. first, by its much greater
complexity of structure ; and, secondly, by
the very peculiar and uniform arrangement,
according to which the spores are developed
in fours at the summits of the basidia.
SECOND PART.
HIGHER CRYPTOGAMIA AND PHANEROGAMIA.
54. In the attempt which we have made in
the preceding sections to discover the order
of succession in which nature has arranged
the various families included among the
Algae, Fungi, and Lichens, we have en-
countered difficulties at every step. The
extension of the same inquiry to the higher
Cryptogamia and Phanerogamia is much more
satisfactory in its results. " The comparison
of the history of the development of the
leafy Mosses and Hepaticae on the one hand,
and of the Equisetaceae, Rhizocarpeae, and
Lycopodiaceae on the other," says Hofmeister,
" has shown the most complete correspondence
of the formation of the fruit of the one with
the formation of the embryo of the other.
The archegonium of the Mosses, the organ
within which the rudiment of the fruit
(Fruchtanlage) is formed, has a structure
altogether similar to that of the archegonium
of the Ferns (in the widest sense) to that
part of the prothallium in whose interior the
embryo of the frond-bearing plant originates,
In both of these large groups of the higher
Cryptogamia, we have a single cell, originating
freely within the larger central cell of the
archegonium, by the constantly repeated divi-
sions of which, in the Mosses, the fruit in
the Ferns, the leafy plant, takes its origin. In
both cases the division of this cell fails to
take place, and the archegonium aborts, if the
spermatic filaments (Saamenfaden) do not
reach it at the moment that its summit gives
way." *
55. The higher Cryptogamia and Phanero-
* Hofmeister, Vergleichende Untersuchungen der
Keimung, Entfaltung u. Fruclitbildung hoherer