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form the procarp of E. vernicata J. Ag. The thallus, accord-
ing to the above, is cylindrical, very much branched on all sides
with small hooked spines, and has a distinct filamentous struc-
ture. There is a rather thick, long-jointed central axis, with
an alternating, inclined, jointed apical cell. This sends off in
alternate order dichotomously branched filaments which grow
diagonally upwards. These branches are more loosely con-
structed and longer jointed toward the center, but toward the
cortex become smaller celled and closer, lying finally side by
side. The inner layer is more or less quickly traversed with
dichotomously branched short-celled rhizoids. The central
axis is surrounded by numerous analogous filaments running
lengthwise. Gonidia are found in great numbers in the thick-
ened branches of certain sections of the thallus. Procarps are

297



298 MINNESOTA BOTANICAL STUDIES.

found in the somewhat loosened, fruit-bearing section of the
thallus appearing in great numbers in the central part of the
cortex. A short, two or more celled, many forked, small second-
ary side-branch of a filament forms an auxiliary cell from an
end cell. Near the auxiliary cell is developed a three-celled
carpogonial branch bent in shape of a hook. The gonimoblast
apparently arises from the fecundated auxiliary cell, branches
profusely, at times towards the center, into the somewhat loos-
ened tissue of the inner layer. The branches of the gonimo-
blast creep between the rows of cells of the sterile tissue, often
fusing with these cells, and finally the end cells develop into
spores.

The fruit-body is an irregular mass of interlacing fibers of
which the lower, stronger sections of the branches stand out
plainly, with numerous spores irregularly massed in the inter-
stices. The cystocarp, without a special protective layer, is
sunk in the locally, slightly thickened thallus. It protrudes
slightly to one side of the thallus near the short spiny point of
a branch. The fruit wall formed by the local thickening of the
cortex of the thallus does not show a pore.

The same authors describe the reproductive organs of the
Gigartinaceae as follows : Reproduction occurs both sexually
and non-sexually. The tetraspores are strewn over the surface
under the outer cortex or in many irregular groups and then
sunk in the inner cortex of the thallus, or arranged in project-
ing nemathecia. The sporangia usually divide transversely but
they also divide obliquely (Endocladid).

Antheridia are spread over the upper surface of the thallus,
sometimes in the form of small, cup-shaped capsules, opening
outwards, and sunk in the outer cortex of the thallus.

The carpogonial branch develops from a lateral branchlet of
a primary branch. The carpogonial branch is three-celled,
bent inwards like a hook, and connected with the swollen auxil-
iary cell, rich in contents. The fecundated auxiliary cell grows
inwards and develops the gonimoblast branches. The end cells
of these branches are transformed into spores.

Endocladia hamulosa (Ruprecht) J. Ag., described in De-
Toni's Sylloge Algarum, seems to differ from E. muricata only
in the position of the cystocarps. " E. hamulosa seems to
differ from E. muricata only in having the cystocarps at the
bases of the ramuli, while in the latter species they are simply



Warner: OBSERVATIONS ON ENDOCLADIA MURICATA. 299

lateral. We have found both sorts on the same plant so it has
seemed best to include both under the same name" Setchell and
Gardner. This is true also of the specimens examined by me.

Endocladia muricata (P. and R.) J. Ag. is a red alga belong-
ing to the genus Gigartinaceae. The plants studied at the
Minnesota Seaside Station, Vancouver island, seem to be the
typical form. Setchell and Gardner describe two other forms,
E. muricata forma compressa and forma inermis, but as the
specimens in hand have not a particularly flattened frond and
are not destitute of spines, they are probably neither of these
forms.

The plants were found growing on rocks and boulders in the
upper portion of the littoral zone very near high water mark.
They were fastened quite firmly to the substratum. The fronds
are low, from 2-4 cm. in height, shrubby in appearance, and
very dark red or brown in color. The branching is dense and
irregular and the branches are profusely covered with spines.
The frond seems to proceed from a branch which runs hori-
zontally along the surface of the substratum. This horizontal
branch sends off downward branches at the ends of which hold-
fasts are developed. Upright branches develop into the
frond.

Frond. Examining a longitudinal section (Plate XL VI., fig.
4) of the frond a conspicuous central cylinder is seen surrounded
by a mucilaginous sheath. This axis is divided into cells about
three times as long as broad. There appear to be protoplasmic
connections running through the dividing cell walls of the axis
cylinder. Branches are given off quite regularly from this
central axis, the branches arising just below the cross walls of
the central axis, and often from two sides of these cells. These
branching filaments do not extend radially out to the cortex as
described by Harvey, but rather diagonally upward and outward,
terminating in the cortex opposite the lower part of the third cell
of the central axis from which they started (Plate XL VI., fig. 4).
The branching seems to be more or less regular (Plate XL VI. ,
fig. 2]. Two branches are given off from the upper third
of the cell, following somewhat the method of branching of the
central cylinder. The branching, in this way, seems to be quite
regular for about eight cells, when it sends off two branches,
each of these branching dichotomously until the cortex is
reached. There are, however, exceptions to this rule.



300 MINNESOTA BOTANICAL STUDIES.

Massed around the central axis are small round cells. These
seem to have developed, at least in some cases, from the upper
branch (Plate XL VI., figs. 2, a, and j, a) of the original branch
coming from the central axis. Schmitz and Hauptfleisch
speak of these rounded cells as rhizoids, while Harvey does
not discuss their origin, but speaks of them as coating the axis.
In the material studied the branching was not always dichoto-
mous nor did the branches run radially outwards. The fila-
ments in the center of the frond are loosely scattered, being
massed together closely to form the cortex. Examining a cross
section of the frond we find a large round central cylinder
(Plate XL VI., fig. i). Massed around this cylinder are small
round cells. The cells in the center of the section are not con-
nected with filaments showing that the filaments of which these
cells are cross sections run parallel to the central axis. The
tissues are loosely arranged, but towards the periphery dichoto-
mous branching can be observed and these branches held to-
gether by a gelatinous secretion form the periphery.

Holdfast. The holdfast is strong, although quite incon-
spicuous. It does not appear to be disc-like, but rather to be
composed of branches (Plate XL VI., fig. 7). There is a brown
cellular substance which is developed beneath the holdfast.
Apparently the holdfast can be developed at any point where
the horizontal branch may come in contact with the substratum
or at the ends of the small branches which radiate downward
from the horizontal branch.

Asexual Reproduction. Some branches appear slightly
fleshier than others. When sectioned there are found distributed
around them, the tetragonidia. These are developed from the
peripheral cells. In one section (Plate XL VI., fig. 8) we may
find the younger gonidangia the contents of which are not yet
divided, those which have divided obliquely forming two masses,
and the mature tetragonidangium containing four gonidia. As
has been previously stated they do not divide perpendicularly but
obliquely. Plate XL VI., Jig. 8, illustrates a portion of a longi-
tudinal section drawn from the side of the axis cylinder to the
periphery. The same structures would be seen on the other
side of the axis cylinder. Long narrow paraphyses extending as
far again as the tetragonidangia are found which function as a
protection for the gonidia. They are developed from certain
peripheral cells and are made up from fourteen to sixteen cells.



Warner: OBSERVATIONS ON ENDOCLADIA MURICATA. 301

Sexual reproduction. The cystocarps are found on the
branches, sometimes singly, often two on one branch, in which
respect this species differs, as has been stated, from E. hamulosa.
Beyond the cystocarps, sterile tissue extends in the form of a
projection or spine. In a cross section of the cystocarp (Plate
XL VI., Jig. 5) slender branching filaments pass in and out
among the carpospores. The gelatinous sheath of these filaments
is not plainly seen here, the protoplasmic contents alone being
visible, and the cells of the filament have become very much
distorted. The carpospores are uninucleate and vary in shape,
some being spherical, some oblong and others oval. The
wall of the cystocarp has the characteristic structure of
the wall of the frond. Distorted branches connected at
times with the cortical cells are found ramifying through
the structure. The development of the cystocarp has been
given previously in the paper as described by Schmitz and
Hauptfleisch.

The author desires to thank Professor Conway MacMillan
for suggesting the subject for study, Miss Josephine E. Tilden
for a detailed outline of the work, and Professor R. A. Harper
for encouragement and helpful suggestions during the progress
of the work.

BIBLIOGRAPHY.

Postels and Ruprecht. Illustrationes Algarum, 16. 1840.
Harvey, W. H. Nereis Borealis Americana. Part 2. 182. 1852.
Saunders, De A. The Algae. Papers from the Harriman Alaska

Expedition. Proc. Wash. Acad. 3: Part i. 1901.
Agardh, J. G. Species, Genera et Ordines Algarum, 3 : 558. 1876.
Setchell and Gardner. Algae of Northwestern America. Univ. of

Calif. Pub. Botany, 296. 1903.
DeToni, J. B. Sylloge Algarum, 4: 175. 1897.
Engler and Prantl. Die Natiirlichen Pflanzenfamilien. 353. 1897.

EXPLANATION OF PLATE XLVI.

All drawings were made by the aid of a camera lucida.

1. Cross section of the frond. Central axis; small cells surround-
ing central axis ; periphery.

2. Branching of one of the filaments taken about three cells from
the central cylinder. Shows somewhat regular branching, similar to
the branching of the main axis. At the periphery dichotomous branch-
ing is illustrated.



302 MINNESOTA BOTANICAL STUDIES.

3. A portion of the central axis showing a branch which is leaving
it. Protoplasmic axis of the central cylinder. The protoplasm
appears to separate into threads to pass] through the thickened plate.

4. Longitudinal section of frond. Axis cylinder surrounded by
mucilaginous sheath. This figure illustrates the point that the main
branches from the axis cylinder do not run out radially, but diagonally
upward, reaching the periphery opposite the lower end of the third
cell of the central axis from which they started.

5. Cystocarp containing carpospores; filaments ramifying among
he spores.

6. Carpospores and branching filaments.

7. Holdfast. #, horizontal branch; ^, stipe; c, brown cellular
substance developed beneath the holdfast; d, vertical branch.

8. Section showing tetragonidangia and paraphyses in different
stages.



MINNESOTA BOTANICAL STUDIES.



PART III.




PLATE XLVI,



XXVI. OBSERVATIONS ON LAMINARIA BULLATA

KJELLM.

OLGA MUELLER.



The plant, Laminar ia bullata, was first studied by Kjellman
in 1889 from material found by him in St. Lawrence Bay of St.
Lawrence island in Behring Sea. Some of the material used
for these observations was found by Miss Josephine Tilden at
Tracyton, Washington, but the greater part was collected
by the writer near Port Renfrew, on Vancouver island, on the
straits of Juan de Fuca, in August, 1902. From this it appears
that the plant has a wide distribution on the western coast of
North America, extending from Alaska to Puget sound, and
possibly to California.

The writer is deeply indebted to Professor Conw r ay MacMillan
and to Miss Josephine Tilden for helpful suggestions.

The plants collected at Port Renfrew were found growing
attached to rocks in a narrow arm of the sea leading into a
cave. Here the tidal currents were very strong, moving the
plants constantly to and fro, and bringing to them the food and
oxygen necessary for their life. They were found growing in
the sublittoral zone and could be collected only at low tide and
then with difficulty.

EXTERNAL MORPHOLOGY.

The plant, like other members of the Laminariaceae, consists
of three portions ; the holdfast, the stipe, and the lamina. The
distinguishing feature of the plant is its rows of undulations,
or of alternating elevations and depressions, called bullations,
which run nearly parallel to the margin of the lamina, but at
some distance from it. The color of the plant is dark brown.
The margin of the lamina is straight and not undulated. Its tex-
ture is like that of strong, firm, sheet rubber, and its smooth glisten-
ing surface offers but little resistance to the action of the waves.

Plants of various ages were examined. The youngest was a
tiny individual 2.5 cm. in length. The primitive disc showed
to good advantage ; its lower surface was almost flat, while the
margin was slightly irregular, with indications of where the first
hapteric branches would arise.

303



304 MINNESOTA BOTANICAL STUDIES.

The stipe was .8 cm. long cylindrical below and slightly
flattened above where it merged into the lamina. The lamina
was .17 cm. long, rather oblong in shape, showing as yet no
traces of the bullations which are so characteristic of the older
specimens, and the free end of the lamina even in so young a
specimen was not perfect, but slightly notched and irregular
due no doubt to the action of the waves.

The largest specimen studied was found growing at Tracyton,
in quiet water. Its length was 143 cm. and the greatest width
of the lamina was 30 cm.

The holdfast by means of which the plant attached itself to
the rocks on which it grew, consisted of a mass of dichotomously
branched hapteres, which had arisen from above the primitive
disc. These hapteres were brown in color, being of a lighter
shade and of a more delicate texture towards the apex. In this
largest specimen the stipe was unusually short, being but 2.5
cm. in length. Most of the specimens examined showed larger
stipes, as in one whose lamina was 52 cm. long, the stipe had a
length of 8 cm.

The stipe is strong and tough in texture. It retains the
characteristic of the earlier stage of being cylindrical at the
base and flattened where it merges into the lamina.

The laminae of different specimens varied considerably in
outline, some being almost oblong, others broad ovate and
others elliptical.

The texture varies also, the laminae of some plants being
much thicker and firmer than of others. These differences
of form and texture are due, no doubt, to differences in the in-
tensity of the light, and the strength of the tidal currents.

The margins are in every case straight but the apex is almost
always frayed and split. There is often one long split extend-
ing nearly to the base of the lamina, a second one not so deep,
and several minor indentations besides. This splitting takes
place in a direction parallel to the margin of the lamina and
usually near the rows of bullations.

Although splitting seems to be the rule, yet our largest speci-
men showed scarcely a trace of it. This was no doubt due to
the fact that it was found growing in quiet water. Its apex
however was frayed somewhat by the action of the waves.

The region of growth is at the point where the stipe joins the
lamina, and here, in the younger portion of the lamina, the bul-



MUELLER : OBSERVATIONS ON LAMINARIA BULLATA KJELLM. 305

lations are most perfect, being more greatly elevated and de-
pressed, though not so large in diameter as in portions near the
apex.

The plant is a perennial, and towards the older portion of the
lamina the bullations become broader and more shallow until
they finally disappear, leaving the older portion of the lamina
with an even surface (Jig. /).

The greater part of the material was preserved in a five per
cent, solution of formaline, a little alcoholic material was used.
The former proved the more satisfactory. Free hand sections
mounted in glycerine jelly were used for study.

ANATOMY.

Laminaria bullata, like the other members of the Laminari-
aceae consists of three tissues, viz., the epidermal, the cortical,
and the pith. Only the first two are found in the hapteres,
while the stipe and lamina contain them all.

The surface of the plant is covered by a thick structureless
cuticle ; below this are the epidermal cells, prismatic in form,
about one and one-half times as long as broad, but with the
two shorter diameters equal, so that when the cells are seen
from the surface, they appear as cubes or pentagons.

These epidermal cells are densely crowded with chromato-
phores, their chlorophyll being masked by the brown coloring
matter characteristic of the kelps. The outer wall is compara-
tively thick while the lateral and inner walls are rather
thin.

Below the single layer of epidermal cells are found from two
to four layers of cells which are shorter and broader than the
epidermal cells, and not so densely crowded with chloroplasts.
These are the hypodermal cells.

Next to the hypodermal cells are found the cortical cells,
which are more irregular in form, though still prismatic. They
increase in size towards the center of the plant, and are followed
by strengthening cells which are smaller in diameter and longer
than the cortical cells. They also have thicker walls and some
of them are imbedded in the mucilaginous material of the central
part of the plant. These cells are devoid of chromoplasts, but
contain granular protoplasm.

The pith web consists of numerous colorless, interlacing
and anastomosing hyphae embedded in mucilage.



306 MINNESOTA BOTANICAL STUDIES.

HAPTERE.

A longitudinal section of the haptere shows that it is composed
of a layer of cuticle on its surface and below this are the pris-
matic epidermal cells with their numerous chromatophores.
Next to these are two layers of hypodermal cells, and just
within are the cells of the cortex. These are much larger and
more irregular in form than the epidermal cells (fig- j). In the
center of the haptere are found rather thick walled elongated
cells arranged in rows.

These rows run in a straight course to the apex of the hap-
tere (Jig- 4) 9 while cells at the sides of the haptere bend in
curving rows from the circumference towards the center ( figs.
5, 2.) The cells near the end of each row have the power of
dividing and it is here that the haptere increases in length and
in thickness. Both cross and longitudinal sections reveal
numerous circular openings in the hypodermis. These are the
mucilage ducts which in the haptere seems to take the form of
spherical pits. Faint traces of branches may sometimes be seen,
so that it is possible that these pits are in communication with
each other. Each pit is surrounded by little granular secreting
cells.

There is no pith in the haptere, the thick-walled, elongated
cells of the cortex occupying the interior of the haptere.

In the stipe is found much the same arrangement of tissues
as in the haptere, but with this difference, that a pith web occu-
pies a considerable portion of the interior of the stipe.

The lower cylindrical portion of the stipe is hollow with only
traces of the pith web left. In the upper, younger, more flat-
tened portion, the pith web fills the center of the stipe
(fig. 6, A, B).

The cuticle is thicker on the surface of the stipe than on the
haptere ; the epidermal cells are slightly more elongated but
otherwise much like those of the haptere (Jig. p). The hypo-
dermal cells consist of several rows and among them are found
the mucilage ducts. A cross section shows them to be large
elliptical openings, very close together, in fact with only the
bounding cells of each duct between. Each duct appears to
have been formed as a fissure between four or five adjoining
cells (fig. 8). These cells have very granular contents, are
enlarged at the ends of the ducts but compressed where the
ducts are broadest. The longitudinal section shows the ducts



MUELLER: OBSERVATIONS ox LAMIXARIA BULLATA KJELLM. 307

as long cylindrical tubes with the inner side crenate and the
outer straight, and with the secreting cells very granular (jig. J).

The cortex cells of the stipe are not so large as those of the
haptere (Jigs. 10, //) The strengthening cells found near the
pith web, are in general cylindrical in form ; the innermost are
imbedded in mucilage. These cells are characterized by each
possessing an unusually large nucleus. The granular proto-
plasm passes through the center of the cell and communicates
with that of adjoining cells through the end partition walls.

The pith web is formed of interlacing, colorless hyphae. In both
cross and longitudinal sections can be seen some hyphae which
have been cut obliquely and others which have not been cut at
all, showing that they run in various directions. The majority
of them take a lengthwise course, however. The hyphae (figs.
12, /j) have comparatively thick walls, are imbedded in mucilage
and contain protoplasm and some starch grains. Trumpet
hyphae are numerous and are found running lengthwise more
often than crosswise.

In the lamina we see again the same tissues as in the stipe.
The chromoplasts of epidermal and hypodermal cells are more
numerous than in the corresponding cells of the stipe. The
mucilage ducts are not so numerous nor so compressed, being
circular rather than elliptical in outline (Jig. if). The cells of
the cortex are large and cuboidal in form (Jig. 14) and follow-
ing these are the thick-walled strengthening cells, circular or
oval in cross section (Jig. 75), and often arranged in pairs as
though recently divided ; elongated and of uniform diameter in
longitudinal section (Jig. 16). In these cells the hyphae of the
pith web take their origin, as branches from the sides of the
cells, or as a prolongation of the cell proper (Jigs. 15, 16).

In some cases the hyphae can be traced from their origin in
one cell, across the pith web to their termination in another cell
on the other side. The pith web is richly supplied with mucilage,
and imbedded in this are numerous trumpet hyphae which do
not differ from those of the stipe (Jig. //).

The bullations, which are so striking a feature of the plant,
are not due to a thickening of any of the tissues of the lamina,
but rather to a bending in and out of these tissues, the epi-
dermis, cortex and pith web following each other in the same
order and proportion as they do in the even portions of the
lamina.



308 MINNESOTA BOTANICAL STUDIES.

Material in the fruiting condition was not available, and there-
fore observations on the reproduction will be made at a future
time. According to Kjellman the sori are found as oval areas
spread over that portion of the lamina where the old lamina
merges into the new. The sporangia do not differ from those
of other Laminariaceae.

BIBLIOGRAPHY.
Kjellman, F. J. Beringhafvets Algflora, page 46, 1889.

EXPLANATION OF PLATE XLVII.

1. Photograph of Laminaria bullata.

2. Diagram of haptere showing the direction taken by the cells of
the cortex. They run in straight lines towards the apex of the haptere,
but bend outward at the sides.

3. Longitudinal section of haptere showing epidermal cells, hypo-
dermal cells, cortex and a mucilage duct.

4. Cells near apex of haptere, as seen in longitudinal section.

5. Cells from side of haptere showing curving direction of cortex
cells. Longitudinal section.

6. a. Diagram of lower hollow portion of stipe.

6. Diagram of upper portion of stipe.

7. Diagram of longitudinal section of stipe. #, epidermal region;
<5, mucilage duct; c, cortex; d, strengthening cells; <?, pith web.

8. Cross section stipe, showing cuticle, epidermal and hypodermal
cells, mucilage ducts and cortex cells.

9. Epidermal and hypodermal cells of stipe. Longitudinal section.

10. Strengthening cells of cortex of stipe. Cross section.

11. Strengthening cells of cortex of stipe. Longitudinal section.

12. Pith web of stipe. Longitudinal section.

13. Pith web of stipe. Cross section.

14. Cross section of lamina showing cuticle, epidermal cells, hypo-


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