Laboratory Outlines

for

General Botany

FOR THE ELEMENTARY STUDY
OF PLANT STRUCTURES AND FUNCTIONS
FROM THE STANDPOINT OF
EVOLUTION

FIFTH EDITION —

BY

JOHN H. SCHAFFNER

Professor of Botany, Ohio State University

COLUMBUS, OHIO
Published by the Author
1922

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ORATORY OUTLINES —

FOR

ENERAL BOTANY

For the Elementary Study | of |
_ Plant Structures and Functions
from the Standpoint of Evolution

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FIFTH REVISED EDITION

BY

JOHN H. SCHAFFNER

Professor of Botany, Ohio State University

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COLUMBUS, OHIO
PUBLISHED BY THE AUTHOR.

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JOHN H. SCHAFFNER

COPYRIGHT, 1922

CLABES 3332

PREFACE.

! The student
have a fair knowledge of language, mathematics and drawing as well as the
ns of pierced since oe pursuit of ae biological sciences calls for con-

ae is seen. He Should also have some knouledae of plants acquired in
: school and thru nature study. .

to the author’s views any thoro course should include at least the follow-
: _pomplete or in part:
eel (bd. ee CN ELL, XX, XXIL, OX = XG Va XO
TL-XXXIV., XXXVI -XXXIX. (a), XL-XLIL. (a). Coie XIN ox VEE
TX. S-LH., ENG rat cl (a) XVI aX VET EX X-EXXIIE =. Ca);
ae a) Gh eo eV LXV LX XX EXX XI. EXXXKV-
ibe CCV. xX CV IME-Clil CV CVL. CLX: CXIL -CXITI.
“of the types which cannot Ke given in the laboratory period may be

pedis on ae dint will be found useful where it is possible to
tudents prepare some of their own slides. The methods given are for the
part such as have been thoroly tested in the class room by the author himself.

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Eye-piece

AURORISELER

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Draw-tube

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Coarse adjust-
ment: Rack
and pinion

Tube

Fine adjustment :
Continuous Safety
Micrometer
Movement

Dustproof triple nose.
piece with objectives

Abbe condenser
Tris diaphragm

Mirror

Base

Compounp MicroscorprE. BAUSCH

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PLATE I.

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INTRODUCTORY SUGGESTIONS.

What ever may be the opinion in regard to the elementary course of bo‘any,
it is the writer’s belief that the general college or university course should be
largely carried on with the use of the compound microscope; and should cover,
in a general way, the whole plant kingdom, so that the idea of the evolution of
plants and their natural relationships will be made prominent. The student should
have a general grasp of the plant kingdom as a whole, and to accomplish such
a result a large number of forms must be studied. Along with this general idea,
a considerable knowledge of morphology and physiology may be acquired, since
the study should have to do largely with living material. The course should
cover a year with at least two laboratory periods of two hours each, a lecture,
and a quiz with assignments from a suitable text-book. After such a course the
student is well fitted to take up the various departments of advanced work. He
will have acquired a sufficient knowledge of biology to carry on _ intelligently,

whatever special studies he may later choose to pursue, as, anatomy, histology,

cytology, physiology, ecology, taxonomy, genetics, or advanced work in special

groups.

It is often supposed that to accomplish good work it is necessary to have
on hand an expensive equipment and all the facilities which our leading universities
afford. There is, however, a large amount of work that may be done by those who
do not have such an equipment, and substantial progress may be made in the
general facts of the science with little besides what is indicated below.

The student should have the following equipment:

1. A good text-book of botany for general reading.

2. A compound microscope, like the Bausch and Lomb FFS’, having a double

nose-piece with 16 and 4 mm objectives, and 5x and 12.5x eye-pieces;

or the Spencer microscope No. 44 with 16 and 4 objectives, and 6x and
10x eye-pieces. The same stands with complete substage and triple
nose-piece are preferable if one can afford to pay the difference in price.

With the Bausch and Lomb stand the third objective may be the 40 mm,

and this may be used instead of a dissecting microscope.

A number of slides and cover-glasses.

4. A good hand-lens or a dissecting microscope. In case the microscope has a
triple nose-piece it should be fitted with a 40 mm objective.

5. A good note-book with note paper and smooth drawing paper, and also
some bristol board drawing paper for the finer drawings. (See “The
Laboratory Note Book” in appendix.)

6. Loose writing paper for making temporary records and calculations.

7. Two good lead pencils, a No. 3H and a No. 6H. It is also desirable to
have a bottle of India ink or Higgins’ eternal ink and crow-quill or
other suitable drawing pen so that the drawings may be finished in ink.

8. The following instruments are necessary: a. A pair of forceps. b. Several
medicine droppers, c. Some needles set in wooden or bone handles,
d. A scalpel, e. A razor, f. Dishes, watch glasses, butter dishes, and
bottles of various sizes, g. Plenty of clean cotton rags and some paper
blotters.

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6 LABORATORY OUTLINES FOR GENERAL BOTANY.

9. The following simple reagents will be needed on the table: a. e
tle of 50 per cent. aqueous solution of glycerin, b. A bottle re)
or pure, boiled water, c. lodin solution, d. Salt solution, ‘:

aqueous, e. A bottle of ninety-five per cent. alcohol.

4

If a greenhouse is not near, a window garden and aquarium become
pensable. Water plants kept in glass jars with some small water anim
water snails and water beetles, will usually grow with little or no attention
most cases the jars should be covered. 4 :

Many of the specimens may be preserved in various preserving fluids, .
some may be dried. These will be found very convenient in case fresh ma :
cannot be obtained when desired. Microscopic plants may be preserved in W
in homeopathic vials, provided a drop of carbolic acid is added to each bottle
material. Plants like mosses, liveworts, fleshy fungi, stems, roots, rhizomes, et
may be preserved in 70 per cent: alcohol. The ordinary fie enten alge are
usually well preserved in copper salt solution. (See appendix.) Myxomycet:
in the fruiting stage, woody fungi, lichens, some liverworts and many other i
may be kept in a ay Condition in ordinary paper boxes.

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of Buffalo, New York.

The following suggestions are offered especially for the benefit of Labora
students, altho most of the directions will also be useful to the amateur micr
scopist working at home: .
* The microscope must always be handled below the stage and never fitted by
any part above the stage (unless one has an instrument of the new type with a :
rigid arm), otherwise the fine adjustment may be injured. The microscope is/Se ae
very delicate instrument. It must not be inclined for general work, as temporary
mounts will not stay in the field unless the stage is horizontal. While working, NTE
the observer should keep the side of the microscope with the coarse and fi
adjustments toward him. The microscope is not to be moved about to obtain the
light. This can be obtained from almost any direction by adjusting the mirror _
properly. Great care must be taken so as not to run the objective down into the
diaphragm or onto the cover-glass and slide. .The lenses of the microscope must —
not be touched with the fingers. They must be wiped only with a very clean, soft,
cotton cloth or with lens paper. They must be kept scrupulously clean. ‘The
student should learn the different combinations of low and high powers imme- 7
diately and how to change from one to the other without difficulty.

The wiping rags should always be clean, and the slides and cover- Slee
must be kept scrupulously clean. The student should learn at the beginning how
to clean the cover-glasses without breaking them. To do this, take the cover-
glass, moistened in water or alcohol, in the rag between the thumb and forefinger
and hold it at the edges between the thumb and forefinger of the other hand.
In making a mount air bubbles are to be avoided. To accomplish this, atterme
the object has been placed on the slide and covered with a.drop of water, hold |
the cover-glass at the edges between the thumb and forefinger and bring it down
obliquely onto a needle held in the other hand, and then withdraw the needle
gradually. The cover-glass will then settle down on the object surrounded by —
water. No water or other reagent must -be on top of the cover-glass. If too much
water has been put on the slide it may be removed with blotting paper. If the
study of a good specimen cannot be finished in the given time, it may be pre-
served for a number of days by running a little fifty per cent. glycerin under

LABORATORY OUTLINES FOR GENERAL BOTANY. Ty

: wall eee studied are to be ciretally figured and described. The drawings
aay be outlined with the 3H pencil and then finished with the 6H. If time is
hand, the drawing may be finished in India ink with a fine drawing pen.
Learn how to keep the pencils sharpened to a fine point. After sharpening with
the knife rub the point smooth on a piece of paper. The drawings are to be
ed only on the front side of the drawing paper. The notes may be written

‘record of them is to be kept in the notes. The notes on each plant.may be
aie the same as the plate eres the drawings to illustrate it “Phe

ne ad with the other into the tube. In this way the magnified image may be
; ‘directly measured. The actual diameter of the area covered can easily be
: ermined for the low powers by examining a millimeter rule. Learn to keep
both eyes open when taking only ordinary observations in the microscope. Be

If =e Se has a definite eee to environment do not
It must also be remembered that motions are magnified

. the paper.
ee it upside down.

Seog and descriptions, and the qualities required for good work are accuracy, cecale
< s, patience, skill, persistency, good judgment, and logical ways of thinking.
the drawings should be exact in all details; the sketches may be more or less
i Slides smamatic. The notes should be written in the best English at the command ~
es the student. The facts should be stated in concise but complete declarative
_ sentences, without rhetorical ornamentation. The observations must always be
recorded at the time when they are taken. One’s memory should not be trusted
ry much in recording scientific facts.

- Finally, it must be remembered that one of the first things to be accom-
shed is to educate the hand for delicate manipulations. And it is also well to

rte cils or cutting the table, that oculars and objectives are never to be dropped,
that stoppers should not be laid down on the bare table, that books and note-

ooks are not to be soiled by the wet and dirty fingers, that bottles and tumblers

“

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LABORATORY OUTLINES FOR GENERAL BOTAN}

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BRYOPHY TA

PHROPHYTA

GONIDIOPHYTA RHODOPHY TA

CHAROPHYTA,
ZYGOPHYTA

> SCHIZOPHY TA
s MYXOPHYTA

4 a ating 4 eee

PROTOZOA

i ARCHEOPHYTA

PLaTe II]. DIAGRAM oF THE PLANT PHYLA.

PRELIMINARY STUDY OF THE LIVING CELL.

I. Philotria canadénsis (Mx.). Waterweed. (Elodea.)

This is a very common plant growing submerged in ponds, creeks, etc. It
will grow well if simply pulled up and placed in a covered glass jar.

‘1. Carefully pull off a few young leaves and mount on a slide with a drop
of water and a coverglass. Examine under the dissecting microscope. Sketch
the entire leaf under low power of the compound microscope. Make the drawing
about five inches long. Describe the shape, margin, color, midrib.

2. The leaf is composed of cells. How many across the leaf? How many
lengthwise? Is the leaf more than one cell in thickness? About how many cells
on the upper surface?

3. Cut cross sections with the razor by holding some leaves between pieces
or strips of common carrot either fresh or preserved in alcohol. How many
cells in thickness, on the average?

4. Suppose the leaf averages three cells in thickness, about how many cells
in the entire leaf?

5. Under high power, draw several adjoining cells, carefully showing details.
(Draw the walls as represented in Fig. 1). What is the general shape of the
cells? The contents of a cell are protoplasm and sap or water. There is usually
some dead food material present as_ starch.

6. Draw a cell showing the nucleus. Notice that the protoplasm is made up
of cytoplasm, nucleus, and chloroplasts. Where is the green coloring matter?

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Bie te Cree. WALES or7 PHILOTRIA:

What is the color of the rest of the leaf? The green coloring matter is chlor-
ophyll. Estimate the number of chloroplasts in a single cell. How many would
there be in the entire leaf? How does a green plant get its food?

7. Movement of protoplasm. Describe the motion. Do not be satisfied un-
til the rotation is very striking. The room and water should not be too cold.
Does the protoplasm rotate in the same direction in all of the cells? How many

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10 LABORATORY OUTLINES FOR GENERAL BOTANY. vs

seconds does it take for a chloroplast to make the round? Doe. the
move in the cell? The active agent in the movement is the cytenlae
cytoplasm does not move from one cell to another. ;

8. A cell is a small mass of protoplasm, in typical plants (eles

has been discovered, and in many alee ‘the plastids are absent.
9. Treat a fresh leaf with alcohol. Does the protoplasm still move?
effect does the alcohol have on the chlorophyll? Treat a fresh specimen. wit
salt solution. What takes place? Explain the cause. Ask for an explan tio
or study the subject of plasmolysis in a text-book. These cells have a v
(water chamber) inside of the protoplasm and are normally in a turgid =e
dition. Treat the specimen in alcohol with iodin solution. Notice the nucleu zi
and nucleolus. Notice the large sEues grains stained dark aes inside of th
chloroplasts. :
10. Ecological note. Does this leaf have stomata? How is it adage to
its environment? aor

Il. Allium cépa L. Common Onion.

1. Pull off the inner and the outer epidermis from a living scale of an onion.
Mount in water. Compare the cells of the two specimens under low power a
to shape, size, and contents. Notice the wall lined with cytoplasm; also th
nuclei. Draw a number of adjoining cells from the inner epidetmis. Notice the
absence of chloroplasts.

2. Under high power, draw a single cell showing the wall, cytoplasm, and
nucleus.

3. Study the movement (streaming) of the cytoplasm. This can usually ee
seen best at the ends of the cells. Notice the fine strands of cytoplasm stretching
across the cell or across the corners of the cell thru the large central vacuole. S
Make a diagram of a cell showing the position of these streams. z

4. Treat with a drop of iodin solution after killing the cells in acolo
Make a careful drawing of the nucleus under high power showing the nucleoli.
What is the normal number of nucleoli for each nucleus in these cells? Is the —
number constant? Are there any starch grains present stained blue by the iodin? —

III. Streaming of Protoplasm in Hairs.

(a). Tradescantia sp. Spiderwort.

will be found suitable. Rhdoeo discolor Hance, easily grown in eaeeutaeee aide a
window gardens, will also do very well. It blooms almost continuously. :

1. Study the stamen hairs. With a scalpel cut off some of the stamen fila-
ments containing the young hairs. Mount in water. Be careful to get the hairs —
wet, but do not injure them. Under low power, notice that the hair is made up 4
of a chain of cells. Draw. BS

2. Study a single cell under high power. Observe the position of the fe
nucleus; the cytoplasm, filled with small granules, lining the cell wall; and the
large vacuole filled with water thru which granular strands of cytoplasm stretch. —

3. Study carefully the streaming motion of the cytoplasm. Are the streams
constant or can you see changes going on in their position? Watch the position
of the nucleus for some time and describe its motion, Select one that is sus-—

LABORATORY OUTLINES FOR GENERAL BOTANY. 11

pended in the central part of the cell. Make a large, careful sketch of a cell
showing the streaming to good advantage. Plot all the moving streams visible

‘by focusing up and down, and indicate by means of arrows the direction of the

movement.

(b). Cucurbita pepo L.- Pumpkin.

The hairs of the petioles and stems of the pumpkin show protoplasmic stream-
ings quite distinctly and can be used to advantage if material is available.
1. Cut off the hairs close to the epidermis with a scalpel or razor and mount

immediately. Study the streams, especially in the lower cells and plot the paths

of movement indicating the direction in each by means of arrows.

Ayzrezationof chromosomes

Jriple fusion

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X chromaso mes aX chromosomes.
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Nonsexual 3A Vegetative
or vegetative ey cle
eycle

ReSuction division
Seg regation of chromosomes

Fic. 2.— GENERALIZED LIFE CYCLES OF ORGANISMS.

The above diagram should be used from time to time in comparison with
the individual life cycles as the study proceeds.

1. Simple sexual life cycle, the individual being haploid (la—1b—lIc).
Haploid gametophyte — fertilization — reduction division.

2. Simple sexual life cycle, the individual being diploid (2a — 2b— 2c).
Diploid gametophyte — reduction division — fertilization.

3. Life cycle with antithetic alternation of generations (3a—38b—3c—83d).
Haploid gametophyte — fertilization — diploid sporophyte — reduction division.

4. Life cycle with antithetic alternation of generations and xeniophyte (3a and
4a—3b and 4b—3c—3d). MHaploid gametophyte — fertilization and triple fu-
sion — diploid sporophyte and triploid xeniophyte — reduction division.

5. Primitive nonsexual life cycle (5a). Also haploid vegetative and non-
sexual spore propagation.

6. Diploid vegetative propagation (6a).

SERIES I. THALLOPHYTA,

IV. Protocéccus viridis Ag. ABleawcarede vulgaris Meneens Phylu Ay
-Gonidiophyta. Class, Autospore. Order, TretocoreaS Family, Pro aa

dery layer on the bark on the north side of trees, on de rocks, etc, Bee
available at any time of the year.

1. Scrape off some of the green powder from a piece a moist bavle’ and
mount in water. Pick out one of the eee single i and draw under high

some “ane after division. Study and draw aggregates or colonies of two, on
four, and eight cells still united. In how many directions do the cells divide?
Describe the color, shape, and habitat of the eee How does it ae its. food?

for this plant (and as far as possible all Aee Rrebeby in its ‘usual habitat ou e
of doors.

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Fic. 3.— Lire Cycle or PrRorococcus.

3. Its life cycle may be stated as follows: increase in size of the cell, division |
of the cell into two, separation of the daughter cells. Taking no account of the
fact that the cells hang together for some time after division, make a diagram
in the notes illustrating this as indicated in Fig. 3, a. See 5a Fig. 2. oe

4. Make a diagram showing the ancestors of one individual for ten genera- |
tions. See Fig. 3, b.

5. Make a diagram showing the descendants of one individual for ten gen-—
erations. Use an entire page of note paper. See Fig. 3, c.

6. Norte. All plants and animals, whether high or low (except Laney a
forms) are single cells in the first stage of their life. Therefore, in the higher .
forms, the egg or spore also passes thru the two, four, etc., celled stages, and in —
these first stages the cells may also represent a loose aggregate or colony, since _
in many cases, if the cells are separated from each other by artificial means, two: ;

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LABORATORY OUTLINES FOR GENERAL BOTANY. 13

or more plants or animals may be obtained from the egg, which would otherwise -
have produced only one individual. Protococcus shows how it is possible for
a plant to pass from a unicellular condition to a colony, and from the condition
of a colony to a multicellular plant. By what means could this be accomplished?
The mechanical reason for the division of one of these cells may be dependent
on the following facts: All food and waste material must pass thru the wall.
Now the surface of a sphere is equal to D’* and the volume is equal to ¢ 7 D’,
therefore, as the sphere increases in size, the surface continues to become less in
proportion to the volume. How could a cell increase indefinitely in size and still
keep the surface and volume in about the same ratio? What disadvantage or
limit would there be to such a process? These plants have potential immor-
tality, i. e., they do not grow old and die, except by accident. Natural death of
an organism appears to be an acquired character. This plant, with a number of
others to follow, is unicellular and without sexuality. It belongs to the lowest
sub-kingdom of plants, which for convenience may be called the Protophyta.

V. Merismopédia sp. Phylum, Schizophyta. Class, Cyanophycee. Order,
Chroococcales. Family, Chroococcacee.

This organism can usually be found in the sediment of creeks, ponds, or
lakes, especially in shady places where there is some decaying vegetable matter.

1. Mount some of the sediment and examine under high power. Look for
minute, blue-green, more or less rectangular plates of cells. Find colonies of
various sizes, select a perfect one and draw, showing the arrangement of the cells.

2. In how many directions does cell division take place? How does the
colony break up into smaller pieces? Such a flat layer of cells is called a super-
ficial aggregate. Neither plastids nor nuclei are visible in these cells. The nuclei
are very small. The bluish color is due to the presence of a peculiar coloring
matter, phycocyan, in addition to the chlorophyll. Notice the gelatinous nature
of the cell wall. Write a careful description of the plant.

VI. Filamentous Blue-green Algae. (a) Lyngbya sp. Class, Cyano-
phycee. Order, Oscillatoriales. Family, Oscillatoriacee.

The species known as Lyngbya wolle: Farl., which produces large brownish-
black masses in rivers and ponds, or any other large species, may be used. A
large species, appearing like a brown or black slimy layer, quite common in
greenhouses and other moist situations, is also very good for study. This form
can be kept indefinitely in a moist jar of earth.

1. Mount a small mass of the slimy material in water, and study under low
power. Draw several of the greenish-brown threads or filaments showing how
they are interwoven. Notice the disk-like cells which make up the filament. De-
scribe the general character of these plants.

2. Under high power study a single filament. Draw part of a filament, show-
ing the end cell. Why is the end cell more or less hemispherical and the others
disk-shaped? Notice the dark granules. Where are they situated? Notice the -
thick sheath surrounding the cells. Draw a single cell, showing details as
accurately as possible.

3. In how many directions do the cells divide? Where and how does cell
division take place? A filament like this is called a linear aggregate.

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describe. How do ae hormogones escape from the sheath?

(b) Oscillatéria sp. Family, Oscillatoriacez.

layers in ponds, rivers and creeks may be used. They may be: kept for an
_ definite time in a covered glass jar of water. an

1. Mount a small flake in water, study under high power, and draw seve
of the slender filaments. There is no definite sheath present. Describe the col
shape of cells, and cell contents so far as they can be seen. ‘Are the two end
alike? Compare as to size, etc., with Lyngbya. Draw a single cell. 8 = =

2. Study the cenrocncnen Compare with ane method of reproduction in.
Lyngbya. Sgt a

3. Make a careful study of the movement of the filaments: To, ‘ec oee
results the plants should first be placed for some time in direct sunlight and the
water should not be cold. Describe the movement. Why can these plants move
more actively than the Lyngbyas? . i

(c) Ndéstoc commune Vauch. Class, Cyanophycee. Order, Nostocales.
Family, Nostocacee. ae see

This plant is common on damp ground in meadows, pastures, hillsides, eters
After a rain it appears as dark green gelatinous wrinkled or lobed masses. Ite:
may be kept for an indefinite period and will be in good condition atten: soaking
in water.

1. Describe the colony, noting its size, shape, and color. Draw. .

2. Mount and under low power note the general arrangement of the fila- —
ments. Look for the limits of the thick gelatinous wall in favorable plants. 3

3. Under high power note the two kinds of cells composing the filament, —
ordinary cells and heterocysts. Why are the filaments so crooked ¢ Draw a fila- —
ment showing both kinds of cells. .

Ss

VII. Beggiatoa alba (Vauch,). Phylum, Schizophyta. Class, Schizo- —
mycete. Order, Desmobacteriales (Filamentous Bacteria). Family, Beggiatoacee. — St

These plants are usually very abundant in sulfur springs and in shady places
in ponds and stagnant water where decaying vegetable matter is present. Beg-
giatoa may be kept for years in a covered glass jar filled with water, provided
there is a layer of decaying vegetable sediment in the bottom.

1. With a medicine dropper take up some of the black sediment containing
Beggiatoa, mount, and examine under high power. Study the slender, more or
less hyaline filaments, and draw one carefully. Draw a single cell showing the
large sulfur granules. No chlorophyll is present. Describe the plant in general.

2. Study and describe the movement. Do the sulfur granules move in the
cell? How many seconds does it take for the tip of a filament to travel from
one side of the field to the other?

3. How does this plant obtain its food, and upon what does it live? fe
different in this respect from Protococcus? To what physiological group does
Beggiatoa belong; holophytes, saprophytes, or parasites?

Note — These plants are intermediate between the blue-green alge' and the
bacteria. What relation is there between the lack of chlorophyll and the saprophyee 3.
habit ? 5

LABORATORY OUTLINES. FOR GENERAL BOTANY. 15

VIII. Bacteria. Class, Schizomycetze. Order, Bacteriales.
There are three common families of bacteria:

Coccacee, Spherical Bacteria, containing the genus Microcéccus and others.
Bacillacee, Rod Bacteria, containing the genus Bacillus and others.
Spirilacee, Spiral Bacteria, containing the genus spirillum and others.

To obtain Bacilli, make a hay infusion by boiling ordinary dry hay for 15
minutes. Keep in a sterilized covered dish for several days. Also boil some beans,
and after exposing the broth to the air until cool, cover and set aside for two
or three days. Species of Spirillum may be obtained from sewer water, or
by letting water plants decay in a jar of water. Micrococci are common in the
air, and may be obtained on boiled potatoes, gelatin, moist bread, etc., by letting
these culture media remain exposed for a short time and then covering them to
keep in the moisture. The bacteria will soon begin to appear in yellow, pink,
purple, or red patches.

1. Mount some of the hay infusion and examine under high power. Notice
the minute free-swimming hay Bacteria, and draw several individuals. Draw.
several still hanging together in a filament after division: Describe the shape,
color, and movement. Distinguish between the true locomotion of the Bacillus and

the Brownian movement of the foreign particles present in the mount. What is

the cause of each motion?

2. Draw two individuals with spores. The movement is produced by means
of flagella or cilia. -

3. Mount some of the bean broth and notice the putrid odor. Study the
Bacillus present. Estimate the number of bacteria present in the field of the
microscope. Counting the number across the diameter of the field and squaring
will give approximate results. |

4. Suppose you had one bacterium to begin with, and that it and its descend-
ants divided once every ‘hour how many bacteria would there be at the end of each
hour for 48 hours?

5. Mount some material containing Micrococcus. Draw several individuals

and describe.

6. Mount and study some bacteria in the zodgloea stage (bacteria in gela-

tinous masses.) Draw and describe.

7. Mount some water containing Spirillum. Study the peculiar movement.
Draw several individuals and describe. Represent the cell as a real spiral and

not simply as a wavy line.

8. Root-tubercle Bacteria. Collect fresh roots of white clover (Trifolium
repens L..) or alfalfa (Medicago sativa L.). Sketch a rootlet showing numerous
tubercles under dissecting microscope. Crush a large and a small tubercle on
the slide, mount in water, and study the bacteria present. Draw a number of
individuals, showing the following forms: irregular rods, club-shaped, T-shaped,
Y-shaped, and X-shaped. Treat with iodin solution and note the color reaction
of the starch and of the bacteria. This symbiosis is a case of mutualism.

9. Mount some hay Bacilli and some Paramecia together, and compare them
as to size. The Bacillus and the Paramcecium are both single cells. About how
much greater in volume is the Paramcecium than the Bacillus? In order to get
fairly accurate results, find how many times wider, thicker, and longer the one is
than the other. This can be done by projecting the organisms onto the table and
measuring them with a millimeter rule. How near would the comparison hold

with that of a mouse and an elephant?

16 LABORATORY OUTLINES FOR GENERAL BOTANY. us

plants decay in a jar of water exposed to the air. The Paracecium is one eo
most highly developed and specialized annals belonging to the Protozo

Fi ‘ 4 af

IX. Slime Molds. Phylum, Mcay pee Class, Myxomycete. = ae

The Myxomycetes are a group of organisms which approach very near to the
animal kingdom, forming one of the several transition groups from the lower _
plants to the lower animals. They have developed a very complex life histo:
and primative sexuality, se they are very. simple plants. They — ys =

convenient.

(a) Lycogala epidéndrum (Buxb.). Order, Trichiales. | Family, Lvcone
galacee. Eh e

1. Make a sketch showing the naked eye characters of ‘sndividense Tr: the
resting stage (zthalia), and how they are situated on the wood. Describe. ; 5
2. Moisten some-of the downy material (capillitium) and a piece of the =
outer enveloping layer (peridium) in alcohol, and mount in water. Examine
under high power. Is there any cell structure in the capillitium or ss
Draw a part of the capillitium, showing the peculiar markings. : ; ee
3. Draw a few of the individuals (scattered thru the capillitium) in the rest- :
ing stage (spores), and describe.

(b) Hemitrichia clavata ¢Perss: Order, ‘Erichiales.. Family, Trichiacee,

1. Mount one of the sporangia and sketch under low power, ‘Shean. the. =
stalk of the sporangium, the broken peridium, and the mass of capillitium threads ae ‘
Describe shape, color, etc. 7

2. Under high power draw some of the capillitium threads, showing all details |
carefully.

3. Draw some of the individuals in the spore stage.

(c) Stemonitis fusca (Roth.). Order, Stemonitales. Family Stemonita-
cee.

1. Mount and draw one of the plume-like sporangia under the dissenting
microscope, showing the hypothallus, stalk, columella, and capillitium. wi

2. Under high power, draw part of the capillitium, showing how it is attached
to the columella.

3. Draw some of the spores.

(d) Plasmodium.

1. Examine under the dissecting microscope, and describe the plasmodium
or a myxomycete in the moist living condition. This can usually be found on
decaying logs during the spring, summer, and autumn. If living material is not —
at hand, examine pieces of plasmodium preserved in alcohol.

2. The flagellate stage of many species of myxomycetes may be obtained by
simply making hanging drop cultures with water, or water in which decaying
wood has been soaking. Fresh spores of Lycogala will germinate in a day or two,
and the preparation can be examined from time to time under the high power,

A ee
wk

LABORATORY OUTLINES FOR GENERAL BOTANY. i7

(c) Amoéba sp. Protozoa. Class, Rhizopoda. Order, Amcebida. Fam-

If the student has not studied the Amceba in a general course in zoology, it

should be taken up at this point, since the amceboid form probably represents one

of the most primitive type of cells with which we have to deal. Amoebas can gen-
erally be found in the ooze at the bottom of ponds and creeks. To obtain Amcebas
in large quantities, pack a glass jar rather tightly with Ceratophyllum or with
pond lily leaves, and cover with water. The dish should be covered up. After
a week or two, when the plants begin to decay, Amcebas will usually be abundant.

1. Scrape off some of the sediment from the Ceratophyllum leaves and mount
in water together with some of the brown scum present at this time in the jar.
Under high power search for transparent, naked cells of irregular shape, which -
are slowly changing in outline by thrusting out pseudopodia. Sketch the outline
of an individual six times successively, at intervals of ten seconds.

2. Describe the amceoboid movement of the animal, and the formation of the
pseudopodia.

3. Make a careful diagrammatic drawing of a large Amoeba, showing the
outer limiting layer (ectoplasm), the inner more fluid granular part (endoplasm),
the nucleus (if distinguishable), the contractile vacuole, and the various ingested
foreign bodies, as diatoms, desmids, etc.

4. Note—JIn the form following, a return will be made to a typical plant
related to Protococcus.

X. Scenedésmus aquadricatda (Turp.). Phylum, Gonidiophyta. Class,
Autospore. Order, Selenastrales. Family, Scenedesmacee.

Scenedesmus is very widely distributed, and may be found in the sediment
in the bottom of ponds, creeks, etc., along with diatoms and other microscopic
plants at any season. It usually consists of a colony of four, more or less spindle-
shaped, green cells. The two outer cells have four slender, pointed, prong-like
projections extending diagonally outward, one at each corner of the colony.

1. Mount some of the sediment containing Scenedesmus, and examine under
high power. Draw and describe.

2. Compare a number of colonies as to size, shape of cells, and appearance
of the projections.

3. In the sediment with Scenedesmus a simpler and much smaller green alga,
Ankistrodesmus falcatus (Corda), belonging to the same family will probably be
present. This consists of very slender, bent or doubly curved cells either separate
or in masses. If present draw and describe.

4. Note— The thallophytes following are more highly developed forms and
possess some type of sexuality or are forms supposed to be descendants from
ancestors having a sexual process. They may be called the sub-kingdom Nema-
tophyta in which the slime molds because of their sexuality may also be placed.

ALG# WITH FANTASTIC CELL WALLS OR WITH COMPLICATED
CHROMATOPHORES.

XI. Diatoms. Phylum, Zygophyta. Subphylum and Class Diatomee.

This class contains a large number of genera and species both living and
fossil. Diatoms can always be found forming brown scums or sediments on the
bottom of ponds, creeks, ditches, etc,

2

18 LABORATORY OUTLINES FOR GENERAL POEs Ga an.
1. Mount some sediment or water containing Aare and ee the
species present. They will probably all belong to the order, Naviculales.
2. Under high power, draw six different species, representing them from t
to four inches long. They are unicellular plants with two ‘cilicified valves”
shells which fit together like the lids of a pill-box. Represent. carefully the mat
ings on the shell. In some species the ends and central portion of the valves. are
marked by nodules and these points are connected by a rib or suture called the
raphe. These can be seen from the valve view. : see
3. Notice the greenish, yellow or brown chromatophores, the nucleus, and
the cytoplasm. How are the cell organs arranged?
4. Look for chains or filaments of diatoms; also for stalked forms. be
5. Study dividing forms. Some species conjugate. Look for such forms. — ;
6. Study the movement. Does it have any relation to the field of the -micro- aie
scope, or the intensity of the light in the field? Describe. What is the cause of e
the motion? Remember that the motion is magnified under the microscope. How
long does it take a diatom to pass across the diameter of the field? 3 es
7. Isthmia sp. Order, Eupodiscales. Scrape specimens of Isthmia trom dry,
red or brown alge or study from mounted slides. Isthmia can usually be obtained : :
from dry alge collected on the ‘California coast. Draw a specimen from the girdle ae
view, showing the valves and details of the markings. Notice that the individuals
are of very different sizes. Draw one showing the valve view. Draw an individual —
in process of division. Describe how the valves fit together, how new valves ater
formed, and what is the character of the valves of the two individuals resulting —
from a division. Explain the cause of the difference in size. = S
8. Fossil diatoms. They will probably belong mostly to the order, Eupo-
discales. Study material from the Tertiary deposit of Richmond, Va. Places ane
fragment of the diatomaceous earth in a small bottle of HCl, crush gently and
mount in water, or use prepared mounts. Draw three different species.
9. Nore—Diatoms, on account of the great number of forms, make a good —
study in variation. There is a great variety of patterns without very much advance =
in structure or life cycle —horizontal evolution. Is there any special advantage = ao
in the great variety of fantastic markings on the valves? &

ee XII. Clostérium sp. Phylum, Zygophyta. Subphylum and Class, Con-
jugate. Order, Desmidiales. Family, Desmidiacez. |

Desmids are quite common in ponds and lakes and species of Closterium can
usually be found in the sediments at the bottom, on submerged water plants, or
in large masses floating on the surface. Sometimes Closterium is very abundant
in watering tanks, forming large, green, floating flakes. :

1. Mount in water and observe the large bright green, unicellular plants —
which are more or less curved or crescent-shaped.

2. Draw an individual under high power, showing the cell wall with trans-
verse striations in the central region, the two large chromatophores (chloroplasts) '
with highly refractive bodies (pyrenoids), the large nucleus with nucleolus in the
central, clear space, and the peculiar vacuoles at each end. Notice the dancing,
crystalline granules of calcium sulfate in the vacuoles. (Brownian movement).
Describe in detail, noting especially the symmetrical halves of the cell.

3. Notice the streaming of the cytoplasm between the large chloroplast and
the cell wall. Trace the current around the end of the cell.

4. Look for dividing specimens. Draw and describe.

5. Search for conjugating individuals and for zygospores.

Os

“5 6 APA SD A
i a eae it i

LABORATORY OUTLINES FOR GENERAL BOTANY. 19

XIII. Spirogyra sp. Phylum, Zygophyta. Subphylum and Class, Con-
jugate. Order, Zygnemales. Family, Zygnemacez.

*

Spirogyra grows in stagnant water or slowly flowing streams, forming floccu-
lent, floating masses of a bright green color which are slimy to the touch. It may
be collected at any time but more commonly it conjugates in late summer and
autumn. Some of the species will conjugate if brought into the laboratory and
placed in an open dish of pure water. ‘Metal is very injurious to Spirogyra.

1. Study naked eye characters, noting that the mass is made up of slender
free threads or filaments.

2. Mount a few filaments in water and examine under low power. Notice
the cells with spiral chromatophores (chloroplasts.) Shape of the filaments and
cells? Count the number of cells across the cover-glass (% inch across). How
many? Measure a long filament and estimate the number of cells it contains.

3. Draw part of a filament under low power showing ends, cells, and chro-
matophores. Any difference between the two ends? Describe.

4. Under a high power, draw a cell showing the wall with mucilaginous
sheath, spiral chloroplasts, pyrenoids, nucleus, and nucleolus. How is the nucleus
connected with the other parts?

5. Draw part of a chloroplast showing details of the margin and the pyre-
noids.

6. Treat with salt solution. Draw and describe what takes place.

7. Study the conjugation from fresh material, or if this not at hand, from
material preserved in copper salt solution or from mounted slides. Notice two
filaments side by side and that all the zygospores are in the cells of one filament,
while the cells of the other filament are empty. This indicates a slight differ-
entiation of sex individuals. Draw a piece under low power, showing a number
of conjugated cells.

8. Draw two conjugated cells showing all details carefully, especially the
zygospore or zygote and the conjugation tube.
9. Draw two cells in which the contents of one cell are passing thru the tube.

10. Draw two cells in which the two
rounded processes from the side have just

Cte. =e met.
SS 11. Draw two cells in which the two

O C processes are just beginning to develop.
Gs Ace 12. Describe fully the process of conju-

gation as observed above.

13. Look for cases of parthenogenesis;
od

either with a spore in one cell and a distorted

od protoplast in the other, or with a spore in
C f each of the conjugated cells.
@ 14. Make a diagram in the notes showing

the life cycle by means of diagrammatic figures
of the plant, cells and spores. Compare with
Fig. 2 (la—1b—lI1c).

15. Make a diagram showing the ancestors of one spore for five generations;
take no account of vegetative propagation or of the possible close relationship
of conjugating individuals (see Fig. 4). Compare with Protococcus. How many

Fic. 4— DIAGRAM OF ANCESTRY

ancestors have you yourself had in twenty generations or about 600 years?

=

40 LABORATORY OUTLINES FOR GENERAL BOTANY.

A SERIES OF FORMS TO ILLUSTRATE THE EVOLUTION OF SEX.

XIV. Sphaerélla pluvialis (Flotw.). (Hzematococcus). Phylum, . See Se
Gonidiophyta. Class, Chlorococcee. Order, Volvocales. Family, Chlamydomona- a Oe
dacez. git aio.

Spherella may be found growing in rain water, drain tiles, roof gutters,
pools, or ponds. It is unicellular and green in color or sometimes a bright red.
If a culture is once obtained, it may be preserved on a limestone rock or in a
glazed earthen jar. Put the rock into the water containing the alga and after
some time take it out and lay it away. Whenever material for study is required
the rock need only be placed in-fresh rain water, when a new crop will soon
appear.

1. With a medicine dropper mount some water containing Spherella and ©
examine under low power. Under high power study the large, green or red
spherical cells in the resting condition. Draw. Notice the green and red coloring
matters — chlorophyll and hamatochrome.

2. Draw an individual divided into two, and one divided into four or eight
cells. How does the division take place as regards the cell wall. Compare with

20-0-G O-@ <x
Ce

b — nd
Me -9-88

Fic. 5— Lire Cycies oF SPHARELLA.

Protococcus. Look for an individual in which the four cells are ready to break
thru the old cell wall. The four cells form four free-swimming Spherellas which .
have very loose cell walls. ay

3. Study the active individuals. Describe the shape, color cell contents
(especially the chloroplasts and pyrenoids), and the flagella. The flagella branch
out from a clear body in the pointed end of the cell and pass out thru two ex-
tremely minute openings in the cellulose wall.

4. Study and describe the movement. Which end is directed forward in
swimming? How long does it take an individual to pass across the diameter of
the field? Suppose the diameter is three-tenths of a millimeter, how long would
it take the plant to travel thirty centimeters or one foot? Is the motion rapid or
slow? How many times its own diameter does an individual move in one second?

5. The flagella and other parts may be seen more clearly by adding a small
drop of iodin solution to the water at the edge of the cover-glass. What hap-
pens? How long are the flagella, compared with the size of the body? Look
for the nucleus. Notice the protoplasmic strands which pass from the cell-body
to the wall.

6. Notice the division of labor in the organism and designate the function
of the following organs: a, cell wall; b, flagella; c, chloroplasts.

o

LABORATORY OUTLINES FOR GENERAL BOTANY. 21

7. Make a diagram in the notes showing the life cycle of Spherella when
reproduction takes place by the formation of non-sexual zoospores. (See Fig. 5a):
Compare with Fig. 2 (5a). oe

8. Sexual stage. Look for individuals divided into eight or more cells:
Draw. When these escape they are smaller than the four and at first have no

cell walls. These zoospores are said to conjugate and form zoozygospores. Care-
ful observation should be made in order to discover such a process. In case

conjugation takes place the life cycle during this stage may be represented as in

_ Fig. 5b. This probably represents the cycle given in Fig. 2 (la—1b—Ic.)

XV. Pandorina morum (Muell.). Order, Volvocales. Family, Volvocacez.

Pandorina occurs in small pools of water, and is often very abundant in
summer, coloring such pools a bright green. The individuals consist of a free-
swimming colony of sixteen cells, and are more or less globular or oval in outline.

1. Mount some of the colonies in water and examine under low power.

’ Notice the active movement. Draw a colony under high power. If they cannot

be followed because of their active movements, add a drop of carbolic acid
water. ‘

2. Notice the details of an individual cell of the colony; the two flagella,
the red eyespot, the transparent spot in the outer end of the cell, and the chlor-
oplast with a pyrenoid.

3. Study and draw colonies in stages of division. Each of the sixteen cells
divides until each forms a group of sixteen new cells, then the gelatinous envelope
dissolves and the sixteen daughter colonies are set free. This is the normal
method of vegetative propagation.

4, Sexual reproduction. Look for colonies in which the cells are separating
as isolated zoospores. These are the gametes which are very much alike, but are
of various sizes.

5. Watch for conjugating forms. Conjugation takes place between two
gametes of equal size, or between a larger and a smaller one. The process is
complete in a few minutes. Draw stages observed, and also mature zygospores.
The difference in size of the conjugating gametes is of special importance, since
it is the first step in the evolution of two specialized gametes, the odsphere and
spermatozoid.

6. Note—Pandorina is well preserved in water with carbolic acid, and
large quantities may be collected at the proper season showing the various stages
of the life cycle. Cultures can also be obtained in the laboratory from dry
zygospores.

XVI. Eudorina élegans, Ehrb. Family, Volvocacee.

Eudorina frequently occurs in summer in pools of rain water, in ponds, and
in marshes. The colonies are hollow, free-swimming bodies, more or less spheri-
cal in shape, usually consisting of thirty-two cells which are considerably sepa-
rated from each other.

1. Mount a drop of water containing the organism and examine under low
power. Under a high power draw a single colony, showing the arrangement of
the cells.

2. Draw a single cell, showing the two flagella, the red eyespot, and the
chloroplast with a pyrenoid.

3. Vegetative propagation. The individual cells divide into sixteen or thirty-
two new cells, and these escape as daughter colonies the same as in Pandorina.
Draw a colony showing daughter colonies, and describe.

a —

IH) LABORATORY OUTLINES FOR GENERAL BOTANY.

4. Sexual reproduction. The colonies are either unisexual or hermaphrodite. ~
Draw a colony showing antherida (spermaries), consisting when mature of plates ;
of sixty-four small cells each, which develop into male gametes (spermatozoids). =
Draw and describe free-swimming spermatozoids. °

5. Draw a colony containing female gametes (odspheres). The colony with
oospheres differs very littlke from the ordinary vegetative colony. Watch - for] 5. —
spermatozoids swarming about the female colonies. eee

6. Draw and describe the ripe, red-colored odspore.

7. Note—Eudorina shows a considerable advance in sexual development
over Pandorina. The female gamete (o0sphere) has become stationary, but still —
retains its flagella at first, and does not divide. The male gametes (spermatozoids)
-are formed by the repeated division of cells of the colony. They are very
small in comparison with the female cell, swim about freely in the water, and — ae ee
_have lost their chlorophyll. Meee.

*

XVII. Vo6lvox glébator L. Family, Volvocacez. as
ee

This alga is of such size that its spherical, free-swimming body can easily be = see.
seen with the naked eye. In summer and autumn it can frequently be found in ape

fresh water ponds and lakes.

1. Take up some of the spherical colonies with a large-mouthed medicine
dropper or a glass tube and, having formed a little chamber on the slide with bite”
a xylonite ring or with paraffin, mount and study under low power. Note the ovecas
rotating movements of the hollow, spherical organism. | eG ©

2. Draw a colony showing the numerous cells and some daughter colonies,
which appear as darker green spherical masses of various sizes,

3. Under high power, study a single colony. About how many cells in a
colony of average size? Draw a few cells, showing the cell walls, the proto-
plasmic strands, connecting the cells (protoplasmic continuity), the chloroplast,
the red eyespot, the pulsating vacuole, and the two flagella of each cell. The
flagella will be more distinct after staining with iodin. | a

4. Describe the development of a daughter colony from one of the cells of
the mother colony. Look for an opening (the pore) in one side of the young
colonies. What advantages may there be in the hollow spherical form?

Be A lie | cit Ea fh a stile

5. Sexual reproduction. The colonies are hermaphrodite, developing both
sexual organs—the ovaries or odgonia and the spermaries or antheridia — in
late summer or autumn. Draw an antheridium. This represents an enlarged cell ee
of the colony which has divided into a large number of elongated cells arranged ag
like a bundle of asparagus shoots.

6. Draw an o6gonium, projecting into the cavity of the colony, showing the AO gay
enlarged odsphere. Draw-a ripe odspore, showing the thick wall with peculiar he
angular points on the surface.

7. Nore—In Volvox complete sexuality has been attained with the normal
conditions of the sexual cells (gametes). It will be noticed that the plant is %
hermaphrodite, and this is the more usual condition in the lower plants.

XVIII. Vauchéria séssilis Vauch. Phylum, Gonidiophyta. Class,
Siphonez. Order, Vaucheriales. Family, Vaucheriacee.

This alga grows as a lax, green, felt-like layer on the surface of moist soil,
and is especially common on the surface of pots or beds in greenhouses, and may oSrae aa
here be in fruit at any time of the year. Other species may be found in ponds. a

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LABORATORY OUTLINES FOR GENERAL BOTANY. 23

1. Describe the naked eye characters, noting the coarse cylindical filaments.

2. Under low power draw an entire filament showing the branches, the tips,
and the clear or decaying part of the back end. Note the absence of transverse
walls. Such a plant body is called a cenocyte. The protoplasts are not separated
by walls. How does the filament grow?

3. Under high power draw a short piece of a young filament, showing details
—shape, vacuole, arrangement of protoplasm, chloroplasts, and oil drops. Posi-
tion of chloroplasts? How can you tell that the filament is cylindrical without
seeing a cross section?

4. Draw several chloroplasts. Shape? Draw some in stages of division.
Describe. Look for movement of the protoplasm. Numerous nuclei are present
in the cytoplasm, but these are not visible without special staining.

5. Study the sexual organs, the antheridium (spermary), and oogonium
(ovary). They are usually side by side. Draw carefully and describe. Notice
the septa which separate the sexual organs from the main filament. Vaucheria
is hermaphrodite, having male and female organs on the same individual.

6. Draw the odsphere (unfertilized egg); also some spermatozoids in the
antheridium. Look for free-swimming or escaping spermatozoids; also for sper-
matozoids entering the odgonium.

7. From the union of the two gametes an oospore or zygote is formed.
Draw a ripe odspore showing the thick wall and more or less hyaline contents.
Describe. Note that fertilization, in this case, is not the stimulus for further
development but is followed by a resting stage.

8. Contrast the two sex cells (gametes) as to size, motion, and nutrition.
How is an oospore different froin a zygospore? S

9. Special vegetative propagation by means of volvox-like SHioniés (com-
pound zoospores), produced in the ends of the filaments, may be obtained as fol-
lows: Place a mass of Vaucheria in a porcelain dish, in water, and expose for a
few days in the window until small Vaucheria plants are found floating on the
surface. Examine very early in the morning and the volvox-like colonies may be
seen escaping from the swollen ends of the filaments. In order to observe the
‘colonies later in the morning, cover the dish, the evening before observation is to
be made, so that the plants will be in absolute darkness until shortly before the
material is to be studied. Study and draw. Describe in detail the formation of
the compound zoospores and how they develop into new Vaucheria plants. Might

Fic. 6— Lire Cycle oF VAUCHERIA.

24 LABORATORY OUTLINES FOR GENERAL BOTANY.

this process indicate some relation of the ancestors of the Vaucheria to the Vol-
vocacez? :

10. Make a diagram in the notes, showing the life cycle of Vaucheria. (See
Fig. 6.) Compare with Fig. 2.

11. In the notes, make diagrams of the two gametes of Spherella, Pan-
dorina, Eudorina, and Volvox, and describe how these may indicate stages in the
evolution of perfectly developed odspheres and spermatozoids. eat

12. Note.— The odsphere and spermatozoid are highly specialized cells, the
first representing nutritive qualities, the second the active qualities. A union of
the two must result in a very perfect reproductive cell. The development of sexual
individuals appears to be along the same lines as indicated in the sexual cells.
Sex expressed as maleness or femaleness is not an hereditary character or factor,
but a condition and often depends on the environment present during the germina-
tion of the spore or the development of the individual. In some of the inter-
mediate plants the sexual development can be controlled while in the higher groups
the sex of the gametophyte is already determined in the spore, but in some cases
the sex of the sporophyte can be controlled artificially.

TWO PECULIAR CENOCYTIC COLONIES.

XIX. Pedidstrum pertusum Kuetz. Phylum, Gonidiophyta. Class,
Hydrodictyee. Order, Hydrodictyales. Family, Pediastracee.

This beautiful alga is found along with other species of the same genus in
the sediments at the bottom of ponds and creeks, and is especially abundant in
the plankton of fresh water lakes and bays in summer and autumn. It is a flat
colony of cells which develop into cenocytes.

1. Mount some of the sediment containing Pediastrum in water and study
under high power. Draw two of the plate-shaped colonies—one with sixteen
cenocytes and one with thirty-two or more. Notice the difference between the
marginal cenocytes and those in the interior. Note also the chloroplast and one
or more pyrenoids.

2. Look for colonies in which the cells in each cenocyte have Separaiew
preparatory to the formation of a new colony.

3. Draw a colony in which some of the cenocytes are empty, each empty
shell having a slit-like opening thru which the daughter colony escaped.

XX. Hydrodictyon reticulatum (L.). Water-net. Family, Hydrodictyacee.

The water-net forms a large body, which is common in summer and autumn
in ponds and canals. It may often be collected in great quantities along the
grassy banks of ponds in city parks. The body of the alga is made up of a very
great colony of cylindrical cenocytes arranged in the form of a sack-like net.

1. Examine a large plant and describe the naked-eye characters. If fresh
material is at hand, place the plant for some time in direct sunlight and note the
bubbles of gas collecting in the nets. Of what use? What is the gas.

2. Draw a small portion of a young net under low power, showing how the
meshes are formed by the joining of a number of cenocytes. Describe.

3. Under high power draw a single cenocyte, showing the chloroplast and
numerous pyrenoids.

4. Vegetative propagation. Study and draw a large cenocyte of an old net
in which the cells are developing a daughter net,

LABORATORY OUTLINES FOR GENERAL BOTANY. 25

° A NUMBER OF COMPLEX ATTACHED FORMS

XXI. (a) Caulérpa crassifolia (Ag.). Phylum, Gonidiophyta. Class,
Siphonee. Order, Bryopsidales. Family, Caulerpacee.

This is a large, much branched, cenocytic plant which reproduces by the
branching of the thallus. The creeping, rhizome-like portion develops leaf-like,
lobed branches, and continues to grow in front while it dies behind. It grows
within the tropics on sandy ocean shores at a depth of several meters. Preserved
material will be necessary. —

1. Sketch the entire plant showing the creeping rhizome-like stem, the leaf-
like lobed branches, and the branching root-like hold-fasts.

2. Mount part of a leaf-like branch and examine under low and high power.
Note that there are no septa or walls in the plant body. Note the chloroplasts.
Draw.

3. Examine a cross section of the cylindrical “rhizome” under low and high
power. Note the numerous branched and anastomosing cellulose braces stretched
across the cavity. Draw.

4. Nore—Caulerpa represents a plant which has developed the extreme
type of a cenocytic body. The body takes on a shape suitable to its activities, by
its branching habit affording sufficient surface for absorption and photosynthesis.
The rigidity of the body is secured. thru the complicated system of braces rather
than by cell walls. Compare Note 6 on Protococcus.

(b) Botrydium granulatum (L.). Phylum, Gonidiophyta. Class, Siphonee.
Order, Botrydiales. Family, Botrydiacez. ;

This alga is common in summer and autumn, especially after heavy rains,
on wet ground in fields and around ponds, where it forms little green pearshaped
bodies with rhizoids extending into the soil.

1. Draw a thallus under dissecting microscope or low power, showing the
pear-shaped erial part and the branching rhizoids. Describe, noting the division
of labor in the plant body and that it is a cenocyte.

2. If material is at hand study some plants which are producing zoospores.
Examine under high power and describe. How many flagella?

XXII. Cladéphora sp. Class, Siphonocladee. Order, Cladophorales.
Family, Cladophoracee.

Species of Cladophora are commonly found in flowing water. They appear
as large, dark green extensively branched tufts, attached to rocks and pieces of
wood. These alge are also abundant along the shores of lakes, where they may
often be found attached to objects which are exposed to the action of waves.
They may be obtained at any season.

1. Describe the naked eye characters; size, mode of growth, color, habitat,
etc. Note the differentiation of base and apex.

2. Mount a small branch of the thallus in water and study under low power.
Draw.

3. Under high power study the stages showing the development of a branch.
Make four drawings showing four general stages: (1) a small bulging out of
the cell wall on one side below the septum; (2) a short branch with the proto-
plasm still connected with the parent cenocyte; (3) the branch cut off from the

mettle

26 LABORATORY OUTLINES FOR GENERAL BOTANY.

parent cenocyte by a septum; (4) a branch divided by a transverse septum into
two cenocytes. :
4. Draw a single cenocyte or division between two cross walls, showing the
irregular chloroplasts and the pyrenoids. Notice the large central vacuole. Apply
salt solution and note the effect. Numerous nuclei are present, but these can
probably not be distinguished from the pyrenoids without special staining. Stain
with iodin solution and draw. It is a cenocytic plant with numerous transverse
walls, but the walls do not represent cell divisions. How and be do the
branches always originate? eae
5. Draw and describe an empty cenocyte or zoosnoraneifg from ae eget
zoospores have escaped. Where is the opening (ostiole) always formed? ~
6. At certain times zoospores may be seen forming and escaping into the
water. This frequently occurs in material which has been kept in water in a warm
room. Draw a cenocyte in which the zoospores are developing.
7. Draw a cenocyte in which the zoospores are fully formed. Look for
zoospores in the act of escaping thru the ostiole.

8. Study and draw free-swimming zodspores, showing the chloroplast and ss os
red eyespot. To make the two flagella visible treat with iodin solution by placing : 2 ae
a drop on the slide beside ‘the cover-glass and letting it mix slowly with the = =
water of the mount. see ag

9. Draw a zodspore which has begun to dese into. a new: filament.“ Tnes ose ae

embryo developing from a free spore is called a sporeling.

yy

10. The zodspores (planogametes) of some species are said to conjugate. =a
Look for such a process. 2

XXIII. Ulothrix zonata (W. & M.). Phylum, Gonidiophyta. Class, e
Confervez. Order, Ulotrichales. Family, Ulotrichacee. ee oe

This Ulothrix is a small, unbranched, filamentous, green alga which usually ae
grows in running water, attached to sticks and stones. It may be found in slow- ei
flowing streams, in watering troughs, or in fountains, Collect the material and g
place it in a shallow dish in about two inches of water, and in a day or two, after ~
the water has evaporated somewhat, large non-sexual zoOspores and sexual gametes 2
will probably be forming. Study the fresh material and preserve some for further =
use. 3

1. Mount some of the filaments containing the basal cells (hold fasts) and
study under low power. Draw.

2. Under high power draw the holdfast, the terminal cell, and two or three
of the central cells; showing the wall, the chloroplast, and the nucleus. Describe
these parts.

3. Non-sexual zodspores. Examine a filament in which the cells are form-
ing either one, two, or four zoospores each. Observe how they escape by a lateral
opening in the cell-wall. Draw and describe. These spores have four flagella
and a pulsating vacuole. Draw an empty cell.

OY Pe es TE ld ae

. Lays y

uw! oe

4. Sexual reproduction. Study a filament in which the cells have developed
a large number (eight, sixteen, or thirty-two) small gametes of equal size (iso-
gametes). Draw part of the filament showing some cells empty and some with
gametes. The gametes have only two flagella.

ee
See pp Ah el
2, Ere Se as oe

ey

x

5. Observe the conjugation of the planogametes to form zoozygospores.

eee
Beppe

“A

Draw and describe. In order to bring out the flagella more clearly, stain with iodin ~
solution. If the gametes do not conjugate some may round themselves off and ey.
become resting spores. This is a case of parthenogenesis. ere
coe.
he

oe

Orr Fi

“<a

J ss)
BF A wnt

ee
Sa

LABORATORY OUTLINES FOR GENERAL BOTANY. Di.

6. Note— When the zygospore germinates it does not develop a new fila-
mentous plant, but gives rise to a number of cells which develop as-non-sexual
zoospores, and these escape and produce the filamentous plant.

XXIV. Ectocarpus confervoides (Roth.). Phylum, Phzophyta. Class,
Pheospore. Order, Ectocarpales. Family, Ectocarpacee.

This alga has a branching filamentous frond and grows in summer attached
to other alge or to submerged objects along the seashore.

1. Note the form of the plant and mode of attachment. Draw.
2. Examine under low power. Are the cells in a single row? Draw a branch.
_ 3. Study and draw a plurilocular sporangium; also draw one of unilocular
sporangia which are usually developed somewhat earlier than the plurilocular
ones. The unilocular sporangia produce non-sexual zodspores and the plurilo-
cular sporangia produce planogametes.

XXV. Fucus evanéscens Ag. Phylum, Phzeophyta. Class, Cyclospore.
Order, Fucales. Family, Fucacez.

This brown alga is common along the Atlantic coast. It may be. obtained
from dealers in botanical supplies, and preserved in alcohol or other solutions,
_ or they may be dried and soaked in water when needed. Various species of Fucus
may be found fresh at fish stores in large cities, these plants often being used as
packing. The thallus is a large, flat, dichotomously branching frond of a dark
brown color, attached to various objects by means of a disk-like holdfast.

1. Place the plant in a plate of water and draw the large thallus. Describe.
Note the holdfast, the flattened dichotomous frond, and the thicker. central region
forming a sort of midrib. Note also the swollen tips of the branches (receptacles),
covered with numerous dot-like projections.

2. Find the growing points of the thallus in branches which do not have
receptacles. Note the emarginate apices which have a slight groove lying in the
plane of the thallus. Draw under low power. The initial cells are at the bottom
of this groove. How are the branches formed?

3. Cut thin cross sections of a branch of the thallus with a razor, mount,
and examine under low power. Draw. Note the outer, denser, cortical layer, and
the loose, inner region, with elongated branched filaments and much mucilage.

4. Cut thin cross sections of a receptacle, mount, and examine under low
power. Note the conceptacles, cavities opening by means of ostioles on the ex-
terior. Sketch the entire section.

5. Select a favorable conceptacle and draw showing the ostiole, the wall of
the conceptacle, the sterile hairs, the large, dark-colored ovaries (oogonia) of oval
form, and the small yellowish spermaries (antheridia) situated on branched hairs.

6. Under high power draw and describe a single antheridium showing cells
developing into spermatozoids. About how many sperms does an antheridium
produce? .

7. Draw and describe an oogonium containing the eight ripe oospheres.

8. Compare the egg and sperm cells. About how much larger in volume is
one than the other?

9. If fresh material can be obtained, study the spermatozoids and oospheres
after their escape from the sexual organs. Take a plant with mature receptacles
from sea water and expose it to the air for several hours. Mount some of the
exudation, which appears at the ostioles of the conceptacles, in sea water, and

28 LABORATORY OUTLINES FOR GENERAL BOTANY.

examine under high power. ‘Notice the large spherical oospheres and the small
motile spermatozoids. Study the process of fertilization, and describe. Draw an
oosphere surrounded by spermatozoids. The discharge of the egg from the ovary
into the water is a very unusual phenomenon in the plant kingdom. Compare
with Vaucheria and Volvex. Study its life cycle. Compare with Fig. 2. (2a—
2b — 2c).

FOUR -PHYCOMYCETES SHOWING VARIOUS ABI PAGS.

XXVI. Mucor stol6nifer Ehrenb. Black Bread Mold (Rhizopus
nigricans. )

Phylum, Mycophyta. Sulphylum, Phycomycete. Class, Zygomycete. Order,
Mucorales. Family, Mucoracee.

This fungus can nearly always be obtained by placing a piece of old bread for
several days in a moist chamber. An ordinary glass or jar with a cover will do
very well for making the culture. Enough water should be added to keep the
bredd moist without soaking it. The fungus forms a white flocculent mass of
cottony filaments (the mycelium made up of hyphae) over the surface of the
bread and later also spreads out over the walls of the glass. Some of the hyphe
will be seen to rise vertically into the air and end in rounded black heads. These
are the sporangia containing the non-sexual spores.

1. Describe the naked eye charcters noted above. Notice habitat and color.
Notice also (1) the hyphae passing down into the substance of the bread, (2) the
horizontal stolen-like hyphae, and (3) the upright sporangiophores.

2. Cut off a flake of the young hycelium with a pair of scissors and mount

in water, taking great care not to injure the delicate hyphae. Study under low -

power and draw some of the hyphe showing mode of branching.

3. Mount carefully and under high power draw part of a hypha and describe.
Any transverse septa (cross walls)? If not, what kind of a fungus is it? (Com-
pare with Vaucheria.) How does this plant differ from the green alge in general?
Difference in mode of obtaining food? Why is this plant called a saprophyte?

4. Study and draw a cluster of sporangiophores showing the rhizoids at the
base and the sporangia at the tips. The best are those taken from the walls of
the dish. Color? Draw a single unbroken sporangium showing the columella on

the inside, and the non-sexual spores. Do not mistake the columella of a broken

sporangium for the entire body. Describe the structure of the sporangium,. What
does the columella represent? The sporangia burst readily because of the presence
of an intermediate substance which swells readily in water. Of what use is this?

5. Draw and describe the non-sexual spores. Color? About how many in a
sporangium ?

6. This plant has a distinct development of sexuality, and under suitable con-
ditions, if the female and male (or + and —) strains are growing together, pro-
duces zygospores. If any of these are at hand or material from another species,
study and draw showing the following stages:

a. Two neighboring branches of the mycelium, which are about to conjugate
and which are in contact.

b. The stage in which the two branches have fused.

c. The stage in which transverse septa are formed, cutting off the apical part
of each conjugating branch. Any difference between the conjugating branches in
size or contents? ;

LABORATORY OUTLINES FOR GENERAL BOTANY. 29

d. The absorption of the wall separating the conjugating tips and the subse-
quent mixing of the two cenocytic protoplasmic masses.
e. The mature zygospore suspended between the two branches.

XXVII. Emputsa miscae Cohn. Fly-cholera Fungus.

Phylum, Mycophyta. Class, Zygomycete. Order, Entomophthorales. Family,-
Entomophthoracee.

This fungus grows on the common house fly (Musca domestica). In the
autumn dead or dying flies attacked by this fungus may be seen with greatly
swollen abdomens of a white color. Specimens may be preserved in alcohol.

“1. Study a fly recently killed by this fungus; under low power without a
‘cover-glass. Note the bands of short white hyphe (conidiophores) protruding
from between the black segments of the abdomen. Draw and describe.

2. Tear open the abdomen: with needles and mount the white contents and
some of the conidiophores in water. Examine under high power. Notice that the
mycelium has nearly absorbed the contents of the fly’s abdomen.

3. Draw some of the conidiophores with conidia still attached; also draw
several of the conidia. Describe. Is the fungus a parasite or a saprophyte?

XXVIII. Saprolégnia sp. Water mold.

Phylum, Mycophyta. Sulphylum, Phycomycete. Class, Oomycete. Order,
Saprolegniales. Family, Saprolegniacee.

This fungus can usually be obtained by placing dead flies in a dish of spring
or pond water. After about five or six days the hyphe of the fungus may be seen
protruding from the body of the fly. On the tips of these hyphe sporangia are
developed which discharge numerous zoospores.

1. Notice the fly in the water, surrounded by a halo produced by the mycelium
of the fungus.

2. Mount some of the mycelium in water and examine under low power.
Draw a branch under high power, showing the granular protoplasm and a terminal
sporangium developing zoospores. Draw a branch showing an empty sporangium.

3. Study and draw free-swimming zoospores. Oospores may also be present.

XXIX. Plasmo6para viticola (B. & C.). Downy Mildew of Grape.
Class, Oomycetae. Order, Peronosporales. Family, Peronosporacee.

This mildew causes a destructive disease of the leaves and young shoots of
the cultivated grape. The infected leaves may be collected in spring or summer
and preserved in 70 per cent. alcohol or dried and kept in paper boxes.

Conidial stage.

1. Examine a leaf carefully under the low power, without cover-glass. On
which side do the conidiophores appear?

2. Carefully scrape off some of the conidiophores with a needle or scalpel,
mount in water, and examine under low power. Under high power draw one of
the much branched conidiophores, If dry material is used the conidia will probably
all have dropped off. One is developed at the tip of each peg-like branch of the
conidiophore.

3. Draw several conidia and describe shape, size, and color,

30 LABORATORY OUTLINES FOR GENERAL BOTANY.

4. From alcoholic material cut cross sections of a part of a leaf containing
the fungus, mount, and under low power note that the conidiophores come out in
bunches thru the stomata of the leaf. Draw.

5. To what physiological group does this fungus belong—— parasite or sapro-
phyte? Describe its mode of life so far as studied.

EXAMPLES OF THE HIGHER ALG.
XXX. Chara sp.

Phylum, Charophyta. Class, Charee. Order, Charales. Family, -Characez.

Stoneworts.

The stoneworts are alge which are found growing in the bottom of ponds,
lakes, or slowly flowing creeks and rivers. They are of considerable size and are
usually covered with an incrustation of lime. They contain numerous branches
arranged in whorls and are firmly fixed in the mud by means of rhizoids. Charas
grow very readily in an aquarium and may be kept in a healthy condition all
winter by simply placing the plants into a glass: jar of water and keeping them
near a south window.

1. Sketch an entire plant and describe the naked eye characters. Notice the
odor, the nodes and internodes, and the brittleness of the filaments.

2. Mount the base of a plant in water and examine under low power. Draw
and describe some of the branching rhizoids. Study the rotation of the proto-
plasm under high power.

3. Mount the terminal part of a young branch, being careful so as not to
crush the brittle lateral branches. Examine under low power and draw the
terminal bud. Notice the great internodal cells covered with a cortical layer and
the whorls of lateral branches. :

4. Draw a cell of one of the branches without a cortical layer, showing the
incrustation of lime.

5. Under high power draw a part of a cell, showing the chloroplasts. How
are they arranged? Draw several in stages of division. How do they divide?

6. Study the rotation of the cytoplasm in the large cells of the branches and
describe. How does it differ from that in the cells of Philotria? Why are the
chloroplasts arranged in rows? Note the movements in opposite directions on
either side of the neutral line. Is the direction of rotation the same in all the
cells?

7. How is the cortical layer developed? In order to determine this, young
branches should be observed. Draw a cross section of the main stem. Note the
short projecting cells which roughen the surface.

8. The sexual organs are produced during summer and autumn. Study
fresh material, or if this is not at hand, material preserved in alcohol or copper
solution. The spermaries (antheridia) and ovaries (oogonia) are situated on the
lateral branches. Draw. Notice the five spiral branches which cover the ovary.
How does this ovary differ from that of Vaucheria? The spermaries are globular
organs which are red in color when fresh. Is this plant hermaphrodite or uni-
sexual? If the incrustation of lime is too thick remove it with Perenyi’s fluid.

9. Crush a ripe spermary under the cover-glass and draw one of the numer-
ous filaments inside. The small cells of these filaments contain the spermatozoids.
Draw a single sell showing a mature spermatozoid. How many cells in a single

i
oa
-
2
Ni
x

nL i eae, Sede: oes

ts

OS ae

/

bere ee a

filament? Suppose the spermary contains 8x6x4 filaments, how many spermato- |

zoids would there be produced in each spermary? How many spermatozoids for
each oosphere or egg?

Bet

LABORATORY OUTLINES FOR GENERAL BOTANY. 31

10. Draw an ovary containing a ripe oospore. Explain the structure of the
entire body. Crush the oospore and note the starch. Treat with iodin.

11. Study the proembryo, from which the normal Chara plant develops as a
lateral bud. Draw and describe. Proembryos may be obtained by placing plants
with mature spores in a glass jar of water and keeping them over winter. In
the spring the embryos will be found at the bottom.

12. Make a diagram showing the life cycle of Chara. Compare with Vau-
cheria and Fig. 2.

XXXI. Batrachospérmum monilif6rme Roth.

Phylum, Rhodophyta. Class, Floridee. Order, Nemalionales. Family, Hel-
minthocladiacee.

Batrachospermum is an alga of considerable size which can be found attached
to stones in fresh water rivulets and creeks.

1. Spread out the frond of the alga in water in a porcelain plate and sketch
the entire plant.

2. Mount some of the branches in water, crushing them considerably under
the cover-glass, and sketch under low power.

3. Under high power draw one of the lateral branches coming out from the
nodes, Note the oval cells and the bristle-like projections on some of the terminal
=cells;

4, In a young, main branch study the branches which pass down from the
base of the nodal branches and form a loose cortical layer. How does this com-
pare with the cortical layer in Chara?

5. Crush some of the older branches under the cover-glass by pressing and
rubbing carefully over the surface with the handle of the needle and study the
ovaries. These are situated on the later branches, and each consists of a
hair-like process (trichogyne) and a thickened bulbous base (trichophore) containing
the odsphere. Draw.

6. Study the spermaries, which are single terminal cells, each of which de-
velops a single spherical male gamete (spermatium) without flagella. Draw a
spermary and a free floating spermatium.

7. Draw an ovary which has one or more spermatia attached to the
trichogyne.

8. Draw a sporocarp under low power. This is a sperical cluster of branches
which develops from the fertilized egg.

9. Under high power draw a nonsexual carpospore at the end of one of the
branches of the sporocarp.

10. From the foregoing study it will appear that Batrachospermum possesses
a sort of an alternation of generations. Besides this, it has another interesting
stage. When the carpospore germinates it gives rise to a peculiar filamentous
proembryo or protonema, formerly known as the chantransia stage, from which
the normal Batrachospermum plant develops as a lateral bud. Protonemal plants
should be collected showing various stages in the development of the Batrachos-
permum bud. The protonemal (chantransia) filament can reproduce itself by
means of non-sexual spores developed on the tips of its branches. This is a case
of reproduction known as pedogenesis, since the process is accomplished while the
plant is in the immature condition. If material is at hand, draw and describe the
chantransia filaments and spores.

eA “

32 LABORATORY OUTLINES FOR GENERAL BOTANY.

XXXII. Polysiphonia variegata (C. Ag.).

Phylum, Rhodophyta. Class, Floridee. Order, Rhodymeniales. Family, Rho-
domelacez.

Polysiphonia grows in abundance on rocky sea coasts. The plants may be —

found in summer as purplish-brown tufts, a few inches long on other larger water-
plants, or on piles and stones. Preserved material may be used by those Nee
away from the seashore.

1. Spread out a frond in a porcelain plate and sketch the entire thallus.
Note the holdfast, if present, and the mode of branching.

2. Mount a branch and draw under low power. Note that the body of the
thallus consists of successive tiers of cells, each tier consisting of a central cell,
surrounded by a layer of cortical cells.

3. Under high power draw a single tier of cells. Crush the thallus a little
and note especially the large protoplasmic strands (protoplasmic continuity) which

run from the central cell to the several cortical cells of the tier. Note also, the —

strands connecting the cells of a tier with those of the tiers above and below.

4. Cut cross sections of the thallus, mount, and study under high power.
The sections may easily be obtained by chopping up a moist branch on a piece of
paper with a sharp scalpel. Draw, showing the arrangement of the central and
cortical cells and also the protoplasmic connections,

5. Under high power study the tip of a young branch and draw. Notice ie
dome-shaped apical cell and a number of cells below. The lower ones are divided
by longitudinal walls. How are the tiers and the cortical cells developed? From
this it is evident that, altho Polysiphonia appears like a branched filament and
continues to develop as such, it finally forms a true solid aggregate.

6. Nonsexual spore reproduction. Mount branches of plants containing tetra-.

sporangia (dark spherical bodies below the cortical cells) and draw under high
power. Draw the spore tetrad and one of the mature spores.

7. Sexual reproduction. The spermaries (antheridia) are borne on delicate,
colorless dichotomously branched filaments, which form tufts on the younger
part of the frond; the ovaries (o0gonia) are on short branches in the upper part,
or the individuals may be unisexual. Mount branches containing spermaries and
draw under high power. Note the slender tip of the branch which extends beyond
the oblong spermary. Note also that the sexual plants have no tetraspores.

8. Development of the ovary. Mount branches containing young ovaries and
under high power draw: (a) a short lateral simple branch showing one of the
cells considerably enlarged and more or less spherical; (b) one in which this
cell has divided by vertical walls into four cells; (c) one in which the inner cell
of the tier of four has enlarged and divided into three or four cells by transverse
walls, the upper one developing into the ovary with a basal trichophore and a
slender trichogyne; (d) a young cystocarp showing the trichogyne protruding from
the mass of cells forming the wall. .

9. Draw a mature cystocarp, showing the more or less ovate-globose wall
and the carpostome.

10. Crush one of the mature cystocarps and draw several of the dark colored,
nonsexual carpospores.

11. Note— Polysiphonia has an alternation of generations, since the spores
of the cystocarp and the tetrasporic plant are homologous to the sporophyte of
higher plants. Note that the sporophyte is at first nursed by the gametophyte then
produces a number of independent spores. Its life cycle may be stated as follows:

‘

LABORATORY OUTLINES FOR GENERAL BOTANY. 33

spermatium

; : Bee eee an

Sexual plant or gametophy te EOenierc \ fertilization germination of oospore
Bat — carpospores —tetrasporic plant or sporophyte (nonsexual)— sporocyte — reduc-
aE tion division — tetraspores — gametophyte, etc. Compare with Fig. 2 (3a—3b—

rs: 8c — 3d).-
aes THE HIGHER FUNGI AND LICHENS

XXXIII. Aspergillus herbaridrum (Wigg.). Common Green Mold.

ees Phylum, Mycophyta. Sulphylum, Mycomycete. Class, Ascomycete. Order,
e __ Aspergillales. Family, Aspergillacee.

=3 E ee This mold is exceedingly common on improperly canned fruit, on cheese and
-~ ee! on decaying plants; especially on plants in press for the herbarium when the driers
SESe are not frequently changed. The conidial stage is of a greenish color while the

ascosporic stage is of a bright yellow-orange to the naked eye.

1. Conidial stage. Mount carefully in water and study under low power.

aoe Under high power draw a conidiophore with conidia. Describe. How are the

oa conidia developed? Draw a piece of the vegetative mycelium, showing the trans-
verse septa.

2. Ascus Stage. Mount some of the white mycelium around the margin of
the yellow centre. Under high power draw some of the peculiar coiled hyphal
bodies present. These represent the conjugating branches, from which a fruiting
‘body develops.

3. Draw the mature fruiting body (ascocarp) under high power, from a
mount of the yellow colored mycelium. Notice the asci containing ascospores.

4. Crush the ascocarps under the cover-glass and draw an ascus with spores.
Describe the life history of the plant. The ascocarp may be compared in a general
way with the cystocarp of Polysiphonia.

XXXIV. Morchélla esculénta (L.). Morel.

: Class, Ascomycete. Order, Helvellales. Family, Helvellacez.
This edible morel is common in spring and summer in moist woods and shady
“= hillsides. Specimens may be preserved in 70 per cent. alcohol.

1. Make a careful sketch of the entire, fleshy, fruiting body, representing the
: stalk and the deep-pitted pileus on whose surface the asci are borne.
ae 2. Tease out a piece of the stalk and mount in water. Examine under
Aa high power and draw some of the mycelial threads. Note that the entire body is a
spurious tissue of interwoven septate hyphe. Compare with Mucor.
3. Tease out a small piece of the pileus, mount, and study the asci. Draw.
How many ascospores in an ascus? How do the asci open at the tips?

eer XXXV. Uncinula salicis (DC.).
—— Class, Ascomycete. Order, Perisporiales. Family, Erysiphacez.

This powdery mildew grows as a parasite on the leaves of various species of
willow and can usually be found without difficulty in the autumn. It forms a white
layer on the surface of the leaf in which minute black bodies are situated. It may
be preserved in 70 per cent. alcohol or kept in a paper box.

1. Moisten a leaf with water and scrape off some of the mycelium con-

- taining the black bodies (cleistothecia). Mount in water and examine under low

3

=

34 LABORATORY OUTLINES FOR GENERAL BOTANY.

power. Under a high power draw a cleistothecium with appendages. Be careful
to have one that is mature.

2. Draw a single appendage. .Of what use are the appendages and the coiled
tips? Draw a small piece of the mycelium showing the transverse wall in the
hyphe.

3. Crush some of the cleistothecia under the cover-glass by pressing and
rubbing carefully over the surface with the handle of the needle. Draw an ascus
containing ascospores. How many asci in a cleistothecium? How many spores °
in an ascus?

XXXVI. Saccharomyces cerevisiae Meyen. Bread Yeast.

Phylum, Mycophyta. Class, Ascomycete. Order, Saccharomycetales. Family,
Saccharomycetacee.

To obtain yeast plants in active, vegetative condition, take a piece of ordinary
dry yeast cake and put it in a glass of water containing a small amount of sugar.
Keep over night in a warm place. |

1. Mount some of the water containing yeast plants and study under high
power. Draw several of the large oval cells present; also a short, branched fila-
ment of cells.

2. Notice the formation of new cells by process of budding. Draw a number
of cells showing the several stages in the formation of a daughter cell.

3. Compare the size of a yeast cell with one of the bacteria present.

4. Stain with iodin solution. Notice the yellowish-brown color of the yeast
plants and the blue of the large starch grains of the yeast cake. Is there any
starch in the yeast cells? .

5. Draw a large cell carefully, showing granules in the protoplasm and one
or more vacuoles.

6. Nore. Yeast plants produce alcoholic fermentation in saccharine solu-
tions. Dry bread yeast is usually a form of the beer yeast, and is known as
“surface yeast.”

XXXVII. Ustilago zéae (Beck.). Corn Smut.

Phylum, Mycophyta. Class, Teliospore. Order, Ustilaginales. Family,
Ustilaginacee.

The corn smut may be collected in summer and autumn and kept in a dry
condition in paper boxes.

1. Make a naked eye sketch of one of the large, black, smut nodules. On
what parts do the smut nodules develop? :

2. Mount some of the black powder and study under high power. Draw a
number of the small pores. These are usually known as chlamydospores, or
teliospores. Describe the color, surface and shape.

3. Make a hanging-drop culture of the spores with dilute, boiled, stable-
manure water. Smut spores germinate quite readily, but it is best to let them
freeze before making the culture. Watch the germination from day to day and
note the formation of the small promycelium or basidium which develops a number
of hyaline basidiospores. Note that the smut plant is a parasite while the pro-
mycelium is a saprophyte.

LABORATORY OUTLINES FOR GENERAL BOTANY. 35

XXXVIII. Puccinia graminis Pers. Wheat Rust.
Class, Teliospore. Order, Uredinales. Family, Pucciniacee.

The aecial stage of the wheat rust occurs in the spring on the leaves of
Berberis vulgaris; the uredinial stage, known as red rust, and the telial stage,
known as black rust, occur on the wheat plant. The infected leaves of the bar-
berry may be preserved in 70 per cent. alcohol and the wheat leaves and stems
may be dried or also preserved in alcohol.

Aecwm.
1. Study the under side of a barberry leaf containing the rust under dissect-
ing microscope. Sketch an entire leaf, representing the position of the diseased

spots.

Fic. 7.— Lire History or PuccrIniA GRAMINIS.

1. Teliospore with basidium (promycelium). 2. Basidiospore (Sporidium,) wuninucleate.
3. Barberry leaf with rust spots. 4. Aecium (clustercup). 5. Pycnium (spermogonium).
6. Conidia (spermatia) from the _pycnium. 7. Aeciospore (binucleate). 8. Stalk of wheat
showing rust pustules. 9. Mycelium from which the uredospores and teliospores are devel-
oped. 10. Uredinium with uredospores. 11. Uredospore. 12. Stalk of wheat showing
rust pustules. 13. Telium with teliospores. 14. Teliospore.

The aeciospore (I.), Uredospore (II.), and teliospore (III.) drawn on same scale.

2. Under low power draw a spot showing the cluster-cups or zcia — cup-like
bodies containing the eciospores.

3. Under low power examine a spot on the upper side of the leaf and note
the little crater-like openings, which are the necks of hollow bodies, called pycnia
(spermogonia), containing thread-like hyphe. Draw.

36 LABORATORY OUTLINES FOR GENERAL BOTANY.

h

4, By means of strips of carrot and a razor cut cross sections of the leaf, _
mount, and study under low power. Under high power draw an xcium, showing
the eciospores. How are they developed? Draw a pycnium with conidia. yes

Uredinwum.

5. Under low power, study the diseased spots on the leaves and stems of
wheat (Triticum aestwwum L.). Draw a patch, showing how the spores break thru
the epidermis. =

6. Pick out some uredospores with a ieedie: or if fresh material is at hand —
cut cross sections of the stem, mount, and asa the uredospores” under high —
power. The uredospores are repeating spores,

Telium.

7. Under low power draw a piece of wheat stem containing the black patches
of teliospores. |

8. Pick out some of the ee or cut cross sections of the stem, mount,
and draw a number of spores under high power. Note that the spore is made up
of two cells. Study variation in individual spores.”

Basidium stage.

9. It is difficult to germinate rust spores in artificial cultures. They germi- 2 eee
nate most readily in spring when those in the field are germinating. Germinate = =
teliospores in a drop culture and study the development oi the promycelium =
(basidium) bearing basidiospores. Draw and describe.

10. Describe in detail the mode of growth and life history of this must noting
especially the presence of heterecism. See Fig. 7.

XXXIX. (a) Fomes applanatus (Pers.). (Elfvingia megaloma (Leyv.).

Phylum, Mycophyta. Class, Basidiomycete. Order, Agaricales. Family, Poly- -
poracee.

This fungus is common on logs and stumps, forming semi-circular brackets
or shelf-like bodies from a few inches to a foot or more in width. It is of a
grayish-brown or white color and may be collected at any season of the year.

1. Draw the entire fruiting body and describe. The vegetative mycelium is pee
in the wood from which the fruiting body projects. Betoun te

2. Under low power study a patch of the pores on the under side, by: simply MS oo
laying the fungus on the stage of the microscope and focusing properly. Draw.

3. From a fresh specimen cut cross sections of a piece of the pore-bearing
layer, mount, and study the basidia projecting into the cavity of the pores. How
many spores on each bascidium. Draw a single spore.

4. Mount some of the brown, woody mycelium from the upper part of the
fruiting body. Draw and describe the structure of the fungus. ae

5. Is the plant a parasite or a saprophyte? Notice the position of the hyme-
nium (pore-bearing surface) in relation to the surface of the earth. Is the myce-
lium of the fruiting body irritable to the force of gravity? Is there any advantage
is this?

(b) Polystictus cinnabarinus (Jacq.). Family, Polyporacee. |

This bracket fungus is very common on dry decaying logs and branches and
is easily recognized by its bright red color, especially prominent on the under
side,

1. Make a sketch of the entire fruiting body. aay

baBORAY ORY OUTLINES FOR -GENERAL-BOTANY. 37

2. Under low power draw a patch of the lower surface showing the pores.
Note especially the bright red color and compare it with the red color present in
many flowers, fruits and roots. How do you explain the presence of the color?

XL. Agaricus campéstris (L.). (Psalliota). Common Meadow Mush-
room.

Class, Basidiomycete. Order, Agaricales. Family, Agaricacee.

This edible toadstool grows in open, grassy places in fields and rich pastures.
The so-called “bricks” of “spawn” can be obtained from seedmen and will keep
for some time when in a dry condition. It can be cultivated by making beds of the
proper character in a cellar or green house, or in the open air in gardens. The
fruiting bodies may be preserved in 70 per cent. alcohol.

1. Take some of the white filaments or strands from the ground in which the
fungus is growing or from a brick of spawn, tease it out with needles and mount
in water. Examine under low and high power. Note the numerous hyphe of the
mycelium and draw. This is part of the vegetative mycelium which takes up the
nourishment from decaying substances in the soil.

2. Examine “button mushrooms” of various sizes and make a series of naked
eye sketches showing how the button develops into the mature fruiting body or
toadstool.

3. Study and sketch the mature fruiting body, showing the cap or pileus with
gills on the under side, and the stalk with the annulus. Note the irregular fringe
at the margin of the pileus.

4. Find the origin of the annulus and the fringe at the margin of the
pileus by studying the veil or vellum of a fruiting body in which the pileus is just
beginning to expand.

5. Cut off the pileus of a mature fruiting body and place it gills downward
on a piece of white paper. In this way a spore print may be obtained in a few
hours. Sketch the spore print.

6. Mount some of the spores and draw under high power. Color and shape?

7. Carefully cut cross sections of the gills of a pileus in which the spores
are not quite mature. Mount and study under high power. Draw a part of the
~ hymenial layer (spore-bearing layer), showing the paraphyses and the larger
basidia, each of which bears two spores.

XLI. Bovista plumbea Pers. Class, Basidiomycete. Order, Lycoperdales.
Family, Lycoperdacee.

This puffball of a dark-brown color, when mature, is usually abundant in
pastures, where it may be gathered in any season. It has a more or less spherical
body, usually from one-half to one inch in diameter.

1. Sketch one of the fruiting bodies, showing the inner peridium with an
aperture at the apex for the discharge of the spores.

_ 2. Pick out some of the internal mycelium (capillitium) and after moistening
with alcohol mount in water. Under high power draw some of the dichotomously
branched mycelium and some of the spores. Describe. How does this plant
obtain its nourishment?

XLII. Lichens.. Certain fungi enter into a peculiar parasitic relation-
ship with various species of aerial blue-green and green alge. These lichen-
forming fungi are mostly Ascomycetae belonging to the phylum Mycophyta.

38 LABORATORY OUTLINES FOR GENERAL BOTANY.

Lichens grow on the bark of trees, on wooden fences, on rocks and on the ground.

The common forms may be collected at any time and kept indefinitely in a dry ~
condition in wooden or paper boxes. The peculiar structures called lichens are ~

then simply associations of fungi and algae representing a condition of symbiosis
known as helotism; i. e. the lichen fungus is a slave holder, the lichen algae are
slaves. In the past, lichens were supposed to be an independent group of plants
but the lichen-forming fungi will have to be distributed among the proper orders
and families of the Mycophyta and the algae among the Schizophyta and Gon-

idiophyta.

(a) Parmélia caperata (L.). Subclass, Discomycetae. Order, Lecanor-
ales. Family, Parmeliacee.

This lichen is of a light green color and is very abundant on trees and fence

boards and rails, forming large circular thalli often a number of inches in
diameter.

1. Study the naked eye characters of the thallus. Draw a part of the thallus,
showing the margin.

2. Soak the thallus in water and tease out a small piece on the slide with
needles. Study under high power. Notice two kinds of cells, colorless septate
hyphe, the lichen fungus, and green spherical cells, the lichen alge. Draw a piece
of the mycelium and some of the alge. To what group do the alge belong? How
are the alge and the fungus hyphe arranged in the lichen thallus? —

3. Draw two or three alge, showing the manner in which the fungus grows
around the green cell to obtain its food.

4. Vegetative propagation. The alga and the fungus each reproduces itself
in the manner peculiar to its species, but the lichen may also propagate itself
directly by means of little granular flakes produced on the upper surface of the
lichen thallus, known as soredia. Mount some of the granular material in water
and examine under low power; notice in favorable specimens that the fungus
and alge are both present in the soredium. Draw and describe.

(b) Sticta amplissima (Scop.). Subclass, Discomycetae. Order, Lecanor-
ales. Family, Stictacez.

This is a foliaceous lichen of a light gray color which grows on the bark of

trees in forests.
1. Soak the thallus in water and note the change in color of the upper sur-
face. Make a sketch showing the position of the brown disk-shaped or cup-shaped

apothecia.
2. With a razor, cut free hand cross sections of a piece of the thallus con-

taining an apothecium. Hold the piece between two strips of carrot. Mount the
sections in water and under low power draw, showing the green algal layer, the
white layer and the position of the apothecium.

3. Under high power study the hymenial layer of the apothecium. Draw
one of the asci containing spores. Describe. How many spores? Draw a single
spore. Draw one of the paraphyses.

(c) Dermatocarpon miniatum (L.). Subclass, Pyrenomycetae. Order,
Pyrenulales. Family, Dermatocarpacez.

This lichen with a rather leathery thallus is common on limestone, where it
may be obtained at any time of the year,

4
Z
4

LABORATORY OUTLINES FOR GENERAL BOTANY. 39

1. Lay the thallus on the slide without a cover-glass and examine under low
power. Draw a part of the thallus, showing the pores which open into the peri-
thecia below.

2. Cut cross sections of the thallus and mount in water. Sketch under low
power, showing the algal and fungal layers and the perithecia.

3. Draw one of the perithecia under high power; also an ascus containing
spores.

(d) Cladénia rangiferina (L.). Reindeer Lichen. Subclass, Discomycete.
Order, Lecanorales. Family, Cladoniacee.

This lichen grows on the ground and is generally present on high wooded
hills or slopes where it often forms large masses.

1. Sketch and describe a large specimen.

2. Draw a branch showing the apothecia on the branchlets.

(e) Synechoblastus nigrescens (Huds.). Subclass, Discomycete. Or-
der, Lecanorales. Family, Collemacez.

A widely distributed, dark colored lichen growing on the bark of trees and
on moss.

1. Sketch the foliaceous body, showing the small circular apothecia.

- 2. Moisten a small piece of the lichen, tease it out with needles, mount and
note the chains of Nostoc cells and the fungus hyphe. Draw.

3. Tease out some of the asci or cut sections, mount and draw under high
power. How many spores in an ascus ? How many cells in an ascospore?

4. Tease out a part of a young lobe of the thallus and also cut sections;
mount and examine for slender hyphe which are coiled at the base. These are
the so-called carpogonia, the slender projecting part being the trichogyne. In
the sections spermogonia, small hollow bodies, may also be found. These bear
spermatia on the hyphal branches lining the walls of the cavity. Draw and describe.

LEHRER. INTERESTING GREEN ALGA:.

-XLIII. Oedogénium crispum (Hass.). Phylum, Gonidiophyta. Class,
Confervee. Order, Oedogoniales. Family, Oedogoniacez.

This plant grows either upon or beneath the surface of ponds and pools,
usually attached to various solid objects. It fruits most abundantly during May
and June, and will grow well in aquaria.

1. Mount some of the filaments in water and examine under low power.
Note that the filaments are unbranched and have a definite holdfast at the base.
Draw.

2. Draw one of the cells under high power, showing the chloroplast with
pyrenoids and the nucleus. Draw the basal cell (holdfast).

3. Nonsexual spore reproduction. If the filaments are in proper condition,
any cell may develop into a zoospore and escape from the cell wall. Draw an
empty cell. Draw a free-swimming zodspore and escape from the cell wall. Draw
an empty cell. Draw a free-swimming zodspore. These have a circle of short
flagella or cilia. Draw a zodspore which has settled down and enlarged and is
developing a holdfast at the base.

4. Sexual reproduction. Note the ovaries or oogonia, large cells each with
an oosphere filled with food material. Draw. Find the opening at the base for

=

40 LABORATORY OUTLINES FOR GENERAL BOTANY.

the entrance of the spermatozoid. Draw a spermary or antheridium, usually con- —
sisting of two or three very short cells each of which gives rise to two sper-
matozoids.

5. Look for escaping spermatozoids and for spermatozoids which have en-
tered the oogonium.

6. Draw an oogonium containing a ripe, thick-walled oospore.

7. When the oospore germinates it divides into four cells, each of which
develops into a zoospore. The zoospores settle down and develop into new
Oedogonium plants. An attempt should be made to have oospores germinate in
a dish of water so that the above mentioned process may be studied. If this stage
is at hand draw and describe carefully. .

8. Write out the life cycle of this plant in the notes, giving the stages in
proper order. Compare with Fig. 2 (la—1b—Ic).

XLIV. Oedogoénium borisianum (LeCl.). Family, Oedogoniacee..

This species grows in stagnant brooks or in ponds and ditches, usually attached
to solid objects. The plants are coarse unbranched filaments and they may be
grown in an aquarium.

1. Mount in water and study under low power. Note the long unbranched
filament and the basal cell expanded into a holdfast. Under high power draw
the tip of a filament, several intermediate cells, and the holdfast. At the summit
of certain cells broad zones with peculiar ring-like straiations may be seen. This
is were cell division has taken place. Draw.

2. Draw a single cell, showing a chloroplast with pyrenoids and the nucleus.

3. Study vegetative cells in which the zoospores are developing. These can
be seen especially in the morning or in material which has been chilled over
night. Draw a single, large zoospore with a circle of short flagella or cilia around
the hyaline anterior end.

4. Draw part of a filament, showing ovaries or oogonia, some with an
oosphere and an opening in the wall for the entrance of the spermatozoid, and
others with thick-walled oospores. Note one or more dwarf males attached to the
cell below the ovary.

5. Draw some of the so-called andro-sporangia, which consist of two +0
five short cells. These cells give rise to zoospores known as androspores, which
settle down on the cells below the oogonia and develop into dwarf male plants.

6. Draw part of a filament with ovaries or o6gonia and one or more mature
dwarf males. Note the large basal cell of the dwarf male and the more slender
spermary or antheridium composed of a number of cells.

7. When the oospore germinates after a period of rest the cell breaks out
in a delicate sack and divides into four cells which give rise to four non-sexual
zoospores. If material is at hand, study and draw.

8. Write out a careful description of the entire life history of this plant.
Compare with Fig. 2 (la— 1b—Tc).

XLV. Coleochaete pulvinata A. Br. Class, Conferver. ~Order,
Coleochetales. Family, Coleochetaceze.

Several species of Coleochete are to be found growing attached to the sur-
face of various submerged, fresh water plants. The species mentioned above
forms hemispherical masses of closely packed, branched filaments. These masses
are large enough to be seen with the naked eye and should be looked for on the
petioles or laminze of water lilies and other hydrophytes.

LABORATORY OUTLINES FOR GENERAL BOTANY. 4]

1. Pick off some of the smaller and larger masses with a scalpel, mount,

and examine under low power. Under high power draw a part of the branching

filaments, showing the joint-like cells, each with a nucleus, chloroplast, and pyre-

noid, and some with long, narrow, hair-like projections, sheathed at the base.

2. Look for nonsexual reproduction by means of zoospores, a single one

i being produced in a cell. If these are present draw and find how they escape

from the cell.
3. Draw the mature ovary or oogonium, showing the oosphere and long

slender, open neck. How different from Batrachospermum?

4. Draw one of the spermaries or antheridia, which are terminal or lateal
flask-shaped cells of peculiar form easily distinguished from the vegetative cells.
Each antheridium produces a single, biflagellate spermatozoid. Compare with
Batrachospermum.

5. Draw a mature spermatozoid either free or in the spermary.

Fic. 8. — Lire CyciLe oF COLEOCH-£TE.

6. Draw an oogonium in which the egg has been fertilized, and around which
branches are developing from the base.

7. Draw an ovary containing a ripe oospore and cortical layer of close--
fitting branches.

8. From material gathered in early spring or from prepared slides, study
fruiting bodies in which a small group of cells has developed by the division of the
oospore. Note the advance of this condition over that of Oedogonium. How
many cells does it contain? —

9. Each cell of the small, oval body develops a zoospore, which after a period
of activity settles down and develops into a new Coleochete thallus.

- 10. Make a diagram in the notes, showing the life cycle of Coleochete. See
Fig. 8. Compare with Fig. 2 (la—1b—JIc).

11. If material is at hand study the flat, disk-like thallus of Coleochete scutata
Bréb. Draw under high power and_describe.

12. Note the Coleochetacee represent the highest green alge, but they show
no approach to the next higher sub-kingdom either in the character of the sexual
organs or the life cycle,

SERIES II — ARCHEGONIATA.

SUB-KINGDOM AND PHYLUM, BRYOPHYTA.

XLVI. (a) Riccia fltitans L. Phylum, Bryophyta. Class, Hepatice.
Order, Marchantiales. Family, Ricciacee.

This liverwort has a small, linear, dichotomously branched thallus which
grows floating in ponds and ditches. It also grows in wet places upon the ground,
sometimes in cultivated fields. The plant keeps well along with other hydrophytes
in a covered, glass jar of water. ;

1. Mount a small thallus or frond (gametophyte) in water and examine
under dissecting microscope. Make a sketch of the plant and describe.

2. Draw a branch of the thallus under low power, showing the air cavities
and cellular structure. Note that this thallus is not made up of branching or
interwoven filaments, but it is a true solid aggregate. Most of the thallophytes
are either simple or complex linear aggregates.

3. The aquatic form of this plant is usually sterile. In order to study the
sexual organs and sporophyte to advantage, examine prepared slides of Riccio-
carpus.

(b) Ricciocarpus natans (L.). Family, Ricciacee.

This plant forms a small, obcordate thallus which floats on the surface of
ponds and swamps. ‘The individuals are hermaphrodite and develop the reproduc-
tive organs in the spring and summer.

1. Sketch the thallus under dissecting microscope. Describe.

2. Under low power draw part of a section from a prepared slide, showing

an antheridium (spermary). Draw part of a section, showing the archegonium

(ovary) containing the oosphere.

3. Draw an enlarged archegonium (ovary) with the spherical sporophyte.
containing a wall one layer of cells in thickness, with the sporocytes lying free in
the interior.

4. From older stage draw spore tetrads and mature spores under high power.

5. If prepared slides are not at hand, cut freehand sections of plants (with
the aid of strips of fresh carrot roots) with male and female organs and draw
an antheridium (spermary) and an archegonium (ovary) under low power. Also
cut sections of a plant containing a sporophyte and some free spores.

6. Compare the sporophyte with that of Polysiphonia. It will not compare
directly with the group of cells developed from the oospore in Coleochaete, be-
cause the Riccia sporophyte is diploid. The antheridium and archegonium may be
compared with the plurilocular sporangia of Ectocarpus. They are not at all like
the sexual organs of the higher green alge.

7. Make a diagram in the notes as shown in Fig. 9, which represents the
general life cycle for all plants above the thallophytes. Note especially that the
diagram represents a life cycle with a true antithetic alternation of generations,
Compare with Fig. 2 (3a —3b—3c—83d). The subsequent diagrams of life cycles,
beginning with Ricciocarpus, may advantageously be platted in concentric circles, the
lowest at the center, with corresponding stages on the same radii. See Wells,
B. W., in Torreya, 27; 45—47. 1921. |

(42)

LABORATORY OUTLINES FOR GENERAL BOTANY. 43

XLVII. Marchantia polymorpha L.
Class, Hepatice. Order, Marchantiales. Family, Marchantiacee.

This thalloid liverwort is common on moist rocks and earth, especially on
cliffs and around springs. Marchantia as well as Conocephalum and Lunularia

@ Sperophzte

Fic, 9.— DIAGRAM SHOWING PRINCIPAL STAGES IN THE LIFE CYCLE OF THE HIGHER
PLANTS.

can be kept without any trouble in a greenhouse or window garden, provided,
they are supplied with sufficient moisture and shaded from intense light by a
curtain. Material may be preserved in 70 per cent. alcohol or in the copper salt
solution.

Gametophyte.

1. Take a thallus (frond) and notice its dorsiventral position on the ground.
Make a naked eye sketch, showing the dichotomous branching, the central groove,
and the emarginate growing points. Describe. How is it fastened to the ground?
How does the thallus continue its development? How is vegetative propagation
accomplished ?

2. Under dissecting microscope study the upper surface. Notice that it is
mapped off into diamond-shaped areas (areole), each with a small opening in
the center (air passage). Draw a patch of the surface.

3. Study the upper surface under low power without a cover glass, by simply
laying the thallus on the slide. Draw several areole carefully. The areole
represent compartments or cavities in the upper surface of the thallus. The thallus
should be kept moist on the under surface as it withers very rapidly.

4. Notice the numerous rhizoids on the under surface. Where are they the
most numerous? Mount some in water and draw the three types under high
power—one with smooth wall, one with scattered peg-like projections in the
interior, and one with somewhat spirally-arranged projections. Of how many
cells does each rhizoid consist? Of what use-are the rhizoids?

=

44 LABORATORY OUTLINES FOR GENERAL BOTANY.

5. With a scalpel or knife cut off some of the minute ventral scales arranged
in two parallel rows on the under side and forming the central ridge. Mount and

draw.
\

\ 2

Ey
mee

oi QUOT

WR,

we
CL
<

Fic. 10.— Lire Cycite or MARCHANTIA.,

6. Some of the thalli will show brood-bud cups. Under dissecting microscope
or low power draw one of the cups containing brood-buds (gemmz). This is a
special method of vegetative propagation. :

7. Mount some of the brood-buds and draw. Notice the two opposite grow-

ing points and the place where the brood-bud was attached to its stalk.

8. Cut cross sections of the thallus thru a cup, with a razor, and under high
power study the development of the brood-buds. Describe.

9. Cut cross sections of the thallus and examine under high power. Where
is the main part of the chlorophyll? Draw part of a section, showing the walls
of the cavities below the areolz, the peculiar chimney-like air passages, the short
filaments containing the chloroplasts, and the cellular tissue below the cavities.
These details can be worked out better from prepared slides, which should be
studied if available and the free hand sections used merely for comparison.

10. Reproductive branches. Draw a plant with an archegoniophore and one
with an antheridiophore. Describe both. Is Marchantia hermaphroditic or uni-

sexual ?

11. Under high power study prepared slides of cross sections (cut at right
angles to the surface of the disk) of the antheridiophore. Draw an antheridium
(spermary), showing the wall, stalk, and the numerous minute cubical mother
cells in the interior, each of which will produce two spermatids which develop into
spermatozoids. About how many cells in each antheridium? How many antheridia
in each disk? Do they all develop at the same time? Notice the openings to the
pockets in which the antheridia are situated. About how many spermatozoids are
there produced in one antheridiophore?

12. In case no prepared slides*are available, cut free-hand sections, mount
in water, and study and draw the antheridia under low and high power.

LABORATORY OUTLINES FOR GENERAL BOTANY. 45

13. From prepared slides study sections of the archegoniophore. Draw an
archegonium (ovary), showing the lid cells, the neck, the neck canal, the venter, the
oosphere and the incept of the perigynium (incipient perigynium). Draw the
venter of an archegonium showing the ventral canal cell and the incipient oosphere.

14. In case no prepared slides are at hand cut sections of the appendaged
_ disk of the archegoniophore, mount in water, and study the archegonia under low
and high power..

15. If male Marchantia plants with properly developed antheridiophores are
‘protected for several days in such a manner that no water will come onto the
disks containing the antheridia, active spermatozoids may be obtained in the fol-
lowing manner: Place a drop of water on the upper surface of the disk and after
a short time take it up with a medicine dropper and mount, or squeeze out several
disks on a slide and mount in water. Under high power numerous motile spermato-
zoids can be seen, each with two flagella. Study their motion for some time, then
stain with a small drop of iodin solution and draw. °

Sperophyte.

16. Carefully pick out a young light-colored sporophyte inclosed in the peri-
gynium, an older stalked one which appears green, and a nearly mature, yellow-
‘colored one from the under side of the archegoniophore, mount in water and
draw under low power, showing the sporangium, stalk, and foot. Describe.
1%. If fresh material is available, place a mature sporophyte, which has a
ruptured sporangium, on a slide without cover-glass and examine. Breathe gently
toward the specimen while making observations. Describe.

18. Under high power draw sporocytes hanging together in chains, and spore
tetrads from crushed sporangia, also some mature spores. Draw one of the
elaters. What is their function?

19. Make a diagram in the notes showing the life cycle of Marchantia. See
Big 10. :

20. EcotocicAL Note. Describe how the air passages and the character of
the nonsexual spores show that Marchantia is adapted to an aerial habitat.

XLVIII. Other Thalloid Liverworts.
(a) Conocéphalum conicum (L.). Family, Marchantiacee.

1. Study the thallus of Conocephalum and compare in general with Mar-
chantia. Draw.

2. Under dissecting microscope, draw part of the surface showing the areole
with air passages. How do they compare in size with those of Marchantia?

3. Under low power without cover-glass, draw an areola showing the crater-
like air passage. Does Conocephalum have any brood-bud cups?

(b) Lunularia cruciata (L.). Family, Marchantiacez.

1. Study the thallus of Lunularia and compare with Marchantia and Cono-
cephalum. Notice especially the numerous semilunar brood-bud cups.
2. Draw a plant under the dissecting microscope, showing several cups.
38. Under low power draw several areole. How many methods of vegetative
propagation has Lunularia? Is there much need for sexual and nonsexual spore
reproduction?

46 LABORATORY OUTLINES FOR GENERAL BOTANY.

XLIX. Porélla platiphylla (L.).
Class, Hepatice. Order, Jungermanniales. Family, Jungermanniacee.

This rather large, scaly liverwort is very abundant on the bark of trees, etc.
It may be kept for a long time in good condition in a paper box. -

Gametophyte.

1. Moisten a branch of the frond in water and sketch from the upper or
dorsal side under the dissecting microscope, showing the arrangement of the
lateral scales.

2. Pick off some lateral scales, being careful so as not to tear off the small,
lower, ligulate lobe which may be seen under the large upper lobe of the scale.
Draw under low power, showing both lobes of the scale. How many cells in
thickness is the scale? Is there any midrib? Why is this scale not homologous
with the leaf of a fern or one of the higher plants? The scales are partly anal-
ogous to leaves.

3. Draw a few cells under high power. Of what advantage are the thick
walls? .

4. Examine the lower or ventral side of a branch under dicsectine micro-
scope and note the semicircular ventral scales. Look for rhizoids. Mount one of
the ventral scales and draw under low power.

Sporophyte.

5. Examine a frond. containing little yellowish, club-shaped bodies. These

are the sporophytes. Carefully pick out one which has the sporangium unbroken
and one which shows the wall of the sporangium split into four valves. Mount
in water and draw both under low power, showing the sporangium, the foot and
the stalk.

6. Draw a spore and an elater under high power.

7. Compare the thallus of Porella with that of Marchantia, noting especially
the different ways in which the two thalli have been specialized for the work of
photosynthesis.

L. Sphagnum Sp.
Class, Sphagnee. Order, Sphagnales. Family, Sphagnacee.

The peat or bog mosses grow in and near water in swamps, bogs, and other
wet places. Some species are unisexual, the male plant being more slender than
the female. Collect plants with sexual organs in winter and early spring and
sporophytes in spring and summer.

Gametophyte.

1. Take a small mass of dry sphagnum, soak it in water and notice the enor-
mous quantity it will absorb.

2. Make a sketch of a female frond. Notice that the frond keeps growing

at the top and dying below.

3. Sketch a branch under low power, showing the arrangement of the scales.
Draw a single scale. Is there any costa (midrib) ?

4. Under high power draw a patch of cells from a scale, some with chloro-
phyll and some showing the peculiar spiral and ring-shaped thickenings on the
inner surface of the wall.

Lao hi
bi Faye, edn, mf ay
UTE TEES CS ea ae

LABORATORY OUTLINES FOR GENERAL BOTANY. 47

5. Mount a piece of the main stem in water and examine under low power.
Draw, showing a central brown cylinder and a cortical layer of clear, large cells
with spiral thickenings.

6. Cut off some of the clavate branches at the tip of the male plant, mount,
-and sketch under low power. Pull off the scales carefully, mount, and examine
the antheridia (spermaries). Draw an antheridium under high power.

7. From a female plant carefully cut out an enlarged archegonium (ovary)
containing a young sporophyte. Mount and draw under low power, showing the
neck at the summit. Around the base some small archegonia may usually be
seen. Draw one of these, showing the stalk, venter, neck and lid cells.

Sporophyte.

8. Pick out a young sporophyte showing the spherical sporangium, the very
short stalk and the expanded bulbous foot.

9. Cut off one of the slender pseudopodia containing a nearly mature sporo-
phyte. Sketch under low power showing the sporophyte with sporangium and
operculum, and the expansion at the top of the pseudopodium into which the
foot fits.

10. Draw some of the non-sexual spores under high power.

11. From prepared slides make a drawing of a longitudinal section of the
sporophyte, showing all the details of the structure.

12.. Study and draw an apical cell from a branch of the gametophyte, from
a prepared slide.

LI. Mosses, General Study. Class, Musci.
(a) The juvenile gametophyte.

When the nonsexual spore of a moss germinates it does not give rise directly
to the mature scaly gametophyte, but develops a green filamentous pro-embryo
known as the protonema. The protonema can always be found in connection with
the very young moss plants which are usually present in greenhouses. The proto-
nema may also be found by examining some of the black earth from a place
where mosses are growing. The ripe spores of any common species of moss
may be sown on moist soil in a box. In a few days, if the box has been covered
with a pane of glass, an abundance of green filaments will begin to appear.

1. Place a little earth with young moss plants into a watch glass and care-
fully wash off the soil by means of the medicine dropper and needle. Mount the
plantlets and any minute masses of filaments present. Examine under low power.
Find a good protonema and draw. Notice the branching, the shape of the cells,
and the chloroplasts. The similar brown filaments present are rhizoids.

2. Draw a single cell, showing the wall, the cytoplasm, and the chloroplasts.
Notice the oblique walls which may be seen in the older filaments. Where and
how do the branches originate?

3. Find a protonema which has developed’ one or more solid green buds
from which the mature sexual moss plants will develop. Draw.

4. With what kind of plants previously studied does the protonema com-
pare? What then could you call the protonemal stage? How can this be used to
explain the evolution of a moss as to habitat, form, and structure? Explain its
evolution on this basis; remembering that the protomema is (1) a single cell,
(2) a simple filament, (8) a branched filament; and that (4) it finally develops
solid buds. These four stages represent the four successive steps in the evolu-
tion of the plant body in going from the lowest unicellular forms to the liver-

4g LABORATORY OUTLINES FOR GENERAL BOTANY. .:

worts. Ontogeny is supposed to partly explain phylogeny, Learn the following ne

law: The history of the development of the individual is an abbneviategs ‘history :
of the development of the race to which it belongs. (See

(b) The young scaly moss plant:
Phiscomitrium turbinatum (Rich. ) ‘(nearly always abundant in greenhouses,
by roadsides, and in old fields) or a species of Mnium will bé suitable.

1. Mount in water and sketch the entire frend under low power, showing

the stem, séales, and rhizoids. =

2. Draw a single scale, carefully showing the costa atid the margin. ‘How BS Pager

does it differ from the scale of Porella? Under high power draw a cell showing

the large chloroplasts and thick wall. As in the liverworts these scales are not —

homologous with true leaves. .
3. Draw a branch of a rhizoid. How do these rhizoids differ from those of

Marchantia? What relation is there between the rhizoids and protonema? Bee

LII. Polytrichum commune L. Common Hair-cap Moss,
Class, Musci. Order, Polytrichales. Family, Polytrichaceez,

The common hair-cap is a widely distributed moss which grows on the ground
in old fields and meadows, on hillsides and in woods. The plants are well pre-
served in a fruit jar with 70 per cent. alcohol, and collections should be made at
various times from winter until early summer when the sporangia are mature.
The plants are unisexual and the material for study should include mature male
and female plants, female plants with the embryo sporophyte developed just far
enough to rupture the calyptra, and female plants with mature or nearly mature
sporophytes.

Gametophyte.

1. Draw the male and female plants (fronds) of the gametophyte genera-
tion, showing the rhizoids, scales, and tip. If the plants are dry or taken from
alcohol, moisten in water. Note the rosette of red scales at the tip of the male
branch and also the slender green scales at the tip of the female branch. Why
this great difference between male and female?

2. Take the tip of a mature male branch and dissect it with needles in a
watch-glass, mount the detached parts and examine under low power. Notice
the paraphyses and the white club-shaped antheridia (spermaries). Do not mis-
take spatulate paraphyses for antheridia. Draw an antheridium under high power.
Draw a spermatozoid from a ripe antheridium.

3. Study the living spermatozoids. These may be obtained if suitable male
branches are collected after several days of dry weather. Take one of the
branches and squeeze out the antheridia onto a slide. Mount in water and observe
the motile spermatozoids.

4. If material is at hand, study and draw antheridia from a stained perma-
nent mount.

5. Dissect the tip of a female plant, mount the detached parts from the
center, and examine under low power. Draw an archegonium (ovary) under
high power, showing lid-cells, venter, and stalk. In good specimens the oosphere
may. be seen.

6. If convenient, study prepared slides containing archegonia, Draw, show-
ing the stalk, venter, oosphere, neck canal, and lid-cells.

a

LABORATORY OUTLINES FOR GENERAL BOTANY. 49

7. Cut cross sections of the scaly stem of a large specimen (using pieces of
€arrot and razor); mount in water and examine under high power: Draw, repre-
senting the épidermal layer, band of peripheral sclerenchyma;, inner cortical layer
of thinner-walled cells, and central strand:

_ Sporophyie.

8. Select a female plant with a youfig sporophyte, pull off the calyptra and
then pull out the young sporophyte, being careful not to tear off its foot. Sketch
the calyptra under the dissecting microscope. What does the calyptra represerit?
Sketch the young sporophyte under dissecting microscope, showing three regions —
foot, short stem, and tip. Remember that the mature sporophyte of Marchantia
has three parts.

9. Draw ‘a mature sporophyte of Polytricum, showing the foot, the stalk
or seta, the hypophysis, and the sporangium or capsule. What important advance
has the sporophyte of Polytrichum and other mosses made over those of Mar-

©
coe oats Ce eee, —_—
QO

Fic. 11.— Lire Cycre oF PoLytTricHuM.

chantia and Sphagnum? Note that the sporophyte is a parasite during its entire
life. Does it manufacture any food for itself?

10. Cut cross sections of the seta, mount, and draw under high power, show-
ing the epidermal layer, the band of sclerenchyma, the layer of thin-walled paren-
chyma, and the central strand. The central strand of the sporophyte may be
compared with the vascular bundle system of higher plants.

11. Ecological note. The hair-cap mosses are subject to great extremes of
moisture and dryness. Let a gametophyte dry out and then place in water. What
occurs? What adaptation has Polytricum for checking the rapidity of evapora-
tion?

12. Make a diagram in the notes showing the life cycle of Polytrichum (see
Fig. 11). Compare with Figs. 2 and 9,

+

50 LABORATORY OUTLINES FOR GENERAL BOTANY.

LIII. Other Mosses.
(a) Amblystegium radicale (Beauv.). (Hypnum.)
Order, Hypnales. Family, Hypnacee.

This is a common moss on decaying logs, in moist, shady places, and on wet
ground. Preserve in 70 per cent. alcohol. The sporophytes are mature in summer

and autumn.

Sporophyte.

1. Take a nearly mature sporophyte, lay it on a slide and examine without
cover-glass under low power. Pick off the calyptra if still attached and the
operculum, being careful so as not to injure the delicate teeth of the peristome.
Draw the operculum and the calyptra.

2. Study the hygroscopic movements of the teeth of the peristome by gently
breathing on the slide while making observations. Describe the movements. Of
what use?,

3. Study the true stomata on the hypophysis. Make a sketch of the sporan-
gium, showing the peristome and the hypophysis with stomata. The hypophysis
may be compared with a leaf of the higher plants.

4. Cut open a sporangium longitudinally and mount. Examine under high
power and draw a stoma, showing the two guard cells and some of the surround-
ing cells. Draw several of the teeth of the peristome and some of the non-sexual
spores. How many teeth are there? Are they in one or two circles?

5. Cut across section of a green sporangiim, mount and examine under low
power. Sketch the section, noting the following structures: epidermis, hypodermal
parenchyma, air space, spore sac, central columella.

(b) AulacOmnium paltstre (L.).
Order, Bryales. Family, Aulacomniacez.

This moss is common in boggy ground and may be found on charred logs
and stumps or on the ground. Collect the material and grow in a moist chamber.

1. Under dissecting microscope make a sketch of a stem, modified in the
upper part, the scales of which are easily detached. These scales act as brood buds,
and when they fall to the ground are able to develop a protonema.

2. Mount some of the detached scales from near the tip and draw under low
power.

(c) Leptobryum pyriférme (L.). Long-necked Bryum.
Order, Bryales. Family, Bryacee.

This interesting little moss may be found on moist, shaded cliffs and on

rocks near water. It is often very abundant and is easily cultivated in greenhouses, ~

where the gametophyte may be obtained at any season. The rhizoids contain
peculiar tuber-like buds of a dark-brown color. On the young sterile fronds these
tuber-like bodies are often numerous, being produced on short rhizoids which
come from the axils of the scales.

1. Crush the enlarged tip of a plant on the slide, mount in water and study
under low and under high power. Draw an antheridum (spermary) and an arche-
gonium (ovary); also one of the paraphyses. Note that this gametophyte is
hermaphrodite. Compare with Polytrichum,

Se te tee,
Pete cs a f
Pe Dee SS aoe eee

LABORATORY OUTLINES FOR GENERAL BOTANY. 51

2. Mount and draw a mature brood-bud under high power, showing the
structure. Describe.

3. Draw a rhizoid with an enlarged, light-colored end cell, the incept of the
brood-bud.

A STUDY OF FORMS WHICH FORESHADOW SOME OF THE STRUC-
TURES DEVELOPED IN THE FOLLOWING SUB-KINGDOM.

LIV. Splachnum ampullaceum L.
Class, Musci. Order, Bryales. Family, Splachnacee.

Altho this odd looking moss is not very common, an attempt should be made
to obtain fresh or preserved material of specimens containing mature or nearly
mature sporophytes. The plant grows on decaying animal tissue or excreta and is
said to occur in cranberry swamps from Ohio to New Jersey and northward.

1. Sketch the entire moss, showing the gametophyte and the sporophyte with
the sporangium and the very large, pyriform, fleshy hypophysis. Describe.

2. Sketch the sporangium and hypophysis under low power, carefully repre-
senting the shape and surface details.

3. Examine the surface of the hypophysis under low and high power and
note the stomata. Draw a small portion of the surface, showing stomata.

4, Notre.— The large hypophysis covered with stomata and filled
with loose tissue is well fitted for the work of photosynthesis and
may be looked upon as foreshadowing the leaf structure found in the
ferns and other higher plants.

LY. Splachnum luteum L. or S. rubrum L.

These remarkable mosses are rather uncommon, and very few
will probably be able to collect specimens; nevertheless an effort
should be made to obtain fresh or preserved material of plants with
nearly mature sporophytes. They are reported mainly from the Rocky
Mountain region.

1. Under low power make a careful drawing of the sporophyte,
showing the foot, the seta, the large umbrella-like hypophysis and
the sporangium (Fig. 12).

2. Draw part of the surface of the hypophysis under high power,
showing the stomata. Are the stomata both on the upper and lower
sides?

3. Compare the hypophyses of Amblystegium radicale, Polytrichum
commune, Splachnum ampullaceum, and Splachnum luteum and note
the progressive development of the hypophysis as represented by these
types. From this comparison it appears that the hypophysis may be
regarded as a nascent, transpiratory and food manufacturing organ.

Bie= 12:

LVI. Anthéceros laevis L. or A. punctatus L. SPOROPH YTE

OF SPLACH-
Class, Anthocerote. Order Anthocerotales. Family, Anthocero- NUM
taceée. ae

The hornworts are common on wet banks and sandstone ledges, especially
around springs and shady places. The gametophyte is a small, lobed, more or less

52 LABORATORY OUTLINES FOR GENERAL BOTANY.

disk-shaped thallus from which the sporophytes extend upward like small ver-
tical horns. Preserve in copper salt solution.

1. Under dissecting microscope, sketch a gametophyte containing nearly ma-
ture sporophytes. Note the thick tubular sheath around the base of the sporophyte.

2. Mount a small piece of the thallus and under high power draw a cell ©
showing the single large chloroplast. Compare these cells with those of Coleo-
chete.

3. Look for endophytic colonies of a blue-green alga (Nostoc) in cavities on
the under side of the thallus. ;

4. Separate a sporophyte, which is just mature at the tip, from the gameto-
phyte, being careful to keep the foot in a perfect condition, and sketch under low
power. Represent the slender sporangium, the bulbous foot with wart-like out- —
growths, and the short stalk with a growing zone between the foot and sporangium
proper. Under high power note the stomata in the green tissue toward the base
of the sporangium.. Draw.

5. Study a sporophyte in which the tip of the Tees has split open.
Notice the columella.

6. Mount some of the spores and spore tetrads and foe under ten power.
Describe the spore tetrads.

7. If prepared slides are at hand, the eae of the foot, the growing region,
and the sporangium should be worked out. Note especially the arrangement of
the elaters, which have a tendency to separate the cavity of the sporangium into
transverse compartments.

8. Note,— The hornworts come nearer to the lowest ferns than any other
Bryophytes and it is probable that the Bryophyte ancestors of the lowest Pterido-
phytes were something like a horned liverwort with perhaps a chlorophyll-bearing
tissue arranged somewhat like the hypophysis‘of a Splachnum. Anthoceros also
points to the Pteridophytes in that it has the sexual organs embedded in the
thallus. In Splachnum and Anthoceros together appear five structures which fore-
shadow or anticipate important structures in the Pteridophytes. These are: (1)
the bulbous foot and wart-like outgrowths of Anthoceros; (2) The central strand
in the seta of Polytrichum and other mosses; (3) the intermediate growing zone
at the base of the Anthoceros sporangium; (4) the large hypophysis of Splachnum
with numerous stomata; and (5) the arrangement of the spores and elaters (sterile
tissue) in the sporangium of Anthoceros.

SUBKINGDOM, PTERIDOPHYTA HOMOSPORAE.

A SERIES OF FERNS TO ILLUSTRATE: THE. EVOLUTION ORC y-
PLEX ORGANS FROM SIMPLE: ONES.

LVII. Ophiogléssum vulgatum L. Adder-tongue.

Phylum, Ptenophyta. Class;-.<Filices.- +: Onder, Ophioglossales. Family,
Ophioglossacee.

This simple fern is mature about the middle of June and may be found in
moist meadows and thickets. The entire plant should be dug up and care taken
so as not to injure any of the roots. Preserve in copper salt solution and press
some for herbarium specimens. Altho fresh plants are preferable, preserved or
dry herbarium specimens will answer very well.

ae ;
‘ 5
Mer

=a
2M
eel
a m
Bee

LABORATORY OUTLINES FOR GENERAL BOTANY. 53

Sporophyte.

1. Sketch an entire plant, carefully representing the four important regions
of the sporophyte —sporangiophore, leaf blade, stem (short upright rhizome),
and roots. Do the roots branch? Note the growing point at the summit of the
rhizome from which new leaves are developed.

2. These four parts may be compared with the organs of a Splachnum
sporophyte in a general way as follows:

a. The sporangiophore with the sporangium.
b. The leaf-blade with the hypophysis.
c. The stem with the seta.
d. The root system with the foot.
Compare also with Anthoceros, noting especially the growing bud in the stem.

'3. Study the venation of the leaf under low power. Draw a portion and
describe. Study and draw the stomata.

4. Mount a part of the nearly mature sporangiophore. Draw under low
power, showing the sporangia. Under high power draw some of the nonsexual
spores.

LVIII. (a) Botrychium simplex Hitch. Little Grape-fern.

Class, Filices. Order, Ophioglossales. Family, Ophioglossacee.

This fern is to be found in moist woods and meadows and should be gath-
ered about the middle of June.

1. Sketch the entire sporophyte from fresh or herbarium specimen and
note the advance in complexity, over Ophioglossum, of the sporangiophore, leaf
and roots.

(b) Botrychium lunaria (L.). Moonwort.

The moonwort is found in the northern part of the United States and
usually grows in fields.

1. Sketch the entire sporophyte, showing the sporangiophore, leaf, roots and
rhizome. Describe how this plant differs from the preceding.

(c) Botrychium negléctum Wood. Matricary Grape-fern.

This fern grows in grassy woods and swamps and should be collected about

the middle of June.

1. Sketch the entire sporophyte and note the advance in complexity over
the moonwort.

LIX. Botrychium obliquum Muhl. Oblique Grape-fern.

This evergreen grape-fern is widely distributed and may be collected in
summer and autumn. Good herbarium specimens are satisfactory.

1. Sketch the entire sporophyte and note the advance in complexity over
the preceding in the development of the sporangiaphore, leaf, and roots.

2. Study the venation of the leaf under low power. Is there any relation
between the development of lobes and the venation?

3. Mount a branch of the sporangiophore and draw several sporangia under
low power. Draw some of the non-sexual spores.

4. Ecological note. Notice the strong root-contraction and draw under dis-
secting microscope. How does the upright rhizome which continues to grow
upward keep in the ground?

2

54 LABORATORY OUTLINES FOR GENERAL BOTANY.

LX. Botrychium virginianum (L.). Virginia Grape-fern.

The Virginia grape-fern is common in rich woods and should be collected in
the summer. Good herbarium specimens are satisfactory.

1. Sketch the entire sporophyte, showing especially the extreme complexity
of the leaf. What relation is there between the ultimate segments of the leaflets —
and the venation?

2. Compare the last five plants in regard to the sporangiophore, the leaf-
blade and the roots.

3. Cut cross sections of the rhizome, mount and draw a sector under low
power, showing the wide cortex, the endodermis, the phloem, the cambium, the
xylem (wood) with medullary rays, and the central pith. This type of vascular
cylinder is called a siphonostele.

4. Cut longitudinal sections of the fleshy root tips, mount the central sec-
tions, and draw a tip showing the apical cell.

5. The gametophytes of the grape-ferns are subterranean and difficult to
find. They are destitute of chlorophyll and have the appearance of minute tubers.
If fresh or preserved material of the gametophyte of the Virginia grape-fern is at
hand, study and sketch under dissecting microscope or low power, showing the
general contour of the body and the rhizoids.

6. Note.— The advance from such forms as Splachnum and Anthoceros to
Ophioglossum represents a vertical evolution, i. e. evolution upwards. The
development indicated in passing thru the series of forms from -Ophioglossum
vulgatum to Botrychium virginianum represents a horizontal evolution. There
is a close relationship among these ferns. It must not be supposed, however,
that the latter has necessarily been derived directly from the former, but only
that the ancestors of Botrychium were at one time in a condition as opie as
Ophioglossum is at the present time.

GENERAL STUDY OF HOMOSPOROUS PTERIDOPHYTES.

LXI.. Fewths.
(a) Adiantum capillus-véneris L. Venus-hair Fern.

Phylum, Ptenophyta. Class, Filices. Order, Filicales. Family, Polypodiacee.

The Venus-hair fern grows in ravines and is widely distributed, but very
rare in the North. It grows very readily in greenhouses, and is extensively
cultivated. The gametophytes may be found at almost any time on pots in
greenhouses. They may be raised in large quantities by sowing spores on any
well-prepared, moist ground.

Gametophyte.

1. Mount a fresh, heart-shaped thallus in water and sketch it from the
upper side under dissecting microscope.

2. Study the rhizoids under low power and draw a single one under high
power. Are they unicellular or multicellular?

3. Under high power draw a single cell of the thallus, showing the chloro-
plasts.

4. Examine the lower side carefully under low power and note the numer-
our antheridia (spermaries) and archegonia (ovaries). How are these organs
distributed over the thallus? Under high power draw an antheridium and an
archegonium (so much as can be seen of them above the surface of the thallus).
Compare the thallus of Adiantum with Anthoceros and Marchantia. Note
especially the comparatively small size of the gametophyte and that it is
hermaphroditic.

LABORATORY OUTLINES FOR GENERAL BOTANY. 55

5. Look for the large, spirally coiled spermatozoids moving in a ripe anther-
idium. Study free-swimming spermatozoids and draw. Describe the movement.
The spermatozoids can usually be found on gametophytes of proper size and
are often present in large number. Jodin will bring out the flagella.

6. If prepared slides are available, draw a section of a nearly mature anther-
idium, showing spermatozoids in various stages of development; also draw an
archegonium, showing the neck, venter and oosphere.

7. Study young gametophytes and recently germinated spores. Note the
protonema. Draw. Compare with the Bryophytes.

Sporophyte.

8. Sketch and describe the compound leaf.

9. Mount and draw a single leaflet under dissecting microscope, showing
the general outline and the free, dichotomous venation. How does the character
of the venation explain the notched and cut margin? Can the origin of the
- leaflets be explained from the same standpoint? Note that the tips of some of
the lobes are bent under so as to cover the sporangia.

10. Under high power study and draw the stomata. Are they on the upper
or lower surface or on both? Draw a single cell, showing the chloroplasts.

11. If slides are at hand draw a section of a young sporophyte embryo,
showing four definite regions (quadrants). |

12. Pick out a young sporophyte from the under side of an old gametophyte,
and draw under low power. Show the four regions, first leaf, root, bud and
foot. Note that the young sporophyte is parasitic on the parent gametophyte,
and that it acquires its independent life gradually.

13. Cut sections of the rhizome, stain and mount or use prepared slides.
Note the general ground tissue and several, scattered, concentric vascular bundles.
Draw.

(b) Ptéris aquilina L. (Pteridium). Eagle-fern.
Family, Polypodiacee.

The eagle-fern grows on hillsides, especially in sunny places. The rhizomes
should be preserved in alcohol.

1. Cut cross sections of the rhizome, mount, and sketch under dissecting
microscope, representing the following structures; the band of external or cortical
sclerenchyma, the pith or ground tissue, internal sclerenchyma (stereome) in two
large, brown bands and in smaller patches, and the concentric fibro-vascular bundles
—usually three large ones and a number of smaller ones. Note the two lateral
ridges. How do you account for the dorsiventral condition of the rhizome? This
type of vascular system is known as a polystele.

2. Under high power, make a careful drawing of one of the smaller vascu-
jar bundles, showing the bundle sheath, usually brown, the phloem and the central
xylem (wood).

3. Test for starch with iodin solution. Draw some of. the ground tissue,
showing the intercellular spaces, and starch in the cells.

4, Draw a patch of cells from the internal and from the external scleren-
chyma, showing the thick cell walls.

5. Cut longitudinal sections of the rhizome, mount and draw, comparing the
structures with those seen in the cross section. Also draw a single cell from the
external sclerenchyma, the internal sclerenchyma, and the ground tissue, From
the vascular bundle, draw a sieve tube and a scalariform tracheid,

Sd

56 LABORATORY OUTLINES FOR GENERAL BOTANY.

6. Describe the mode of growth of the Pteris rhizome. What advantages

in the geophilous habit? Has this rhizome any advantage over the vertical rhi- —

zoines of Ophioglossum and Botrychium?
7; Carefully remove the leaves from the apex of a branch of the rhizome and
cut cross sections of the growing point. Mount the sections, and in the first two

or three look for the apical cell. Draw. Cut longitudinal sections of the apex of —
another branch, mount and draw the section, showing the apical cell. What is the

shape of the apical cell?

&. Under dissecting microscope draw a leaflet of Pteris from the lower
side, showing the membrarious false indusium formed of the reflexed margin of
the leaflet.

9, If fresh, young leaves are at hand, study the nectar glands with drops of
nectar in the axils of the main divisions. Locate them and draw. Of what use
are the nectaries?

(c) Cyrtomium falcatum J. Sm.

Family, Polypodiacee.

Cyrtomium grows readily in greenhouses and window gardens, and fresh
sporangia may be obtained at almost any time of the year.

1. Examine a sterile leaf and a sporophyll. Draw one of the leaflets showing
the circular sori on the under side.

@

ps ake GQ)
@
©

Fic. 13.— Lire Cycie oF ORDINARY FERN.

Pick off some of the sori which have recently exposed the sporangia,
examine without cover-glass and describe how the spores are scattered. j

3. Mount an indusium and some opened and unopened sporangia. Draw the
indusium under low power.

4. Draw a single sporangium under high power, showing the stalk, annulus,
and lip cells. Contrast this sporangium with the one in Botrychium. Draw some
of the nonsexual spores. Note shape, color and surface.

5. Make a diagram showing the life cycle of a fern. See Fig. 13. Compare

with Figs. 9 and 2 (8a —3b—38c— 93d).

PABORALORN: OU LLINES FOR- GENERAL BOTANY. 5

N

LXII. Other Ferns.
(a) Camptos6rus rhizophyllus (L.). Walking-fern.
Family, Polypodiacee.

The walking-fern is common on rocks, especially on limestone. Study fresh
or herbarium specimens.

Sporophyte.

1. Sketch a plant with sevefal leaves, some of which have rooted at the
long acuminate tips, and show plantlets of various sizes. This is a simple and
effective method of vegetative propagation. Leaves are usually highly specialized
organs which have to a large extent lost the power of reproducing the individual.
There are, however, many cases, like the present one, even in the higher plants,
where the leaves retain the power of reproduction to a remarkable degree.

(b) Filix bulbifera (L.). (Cystopteris.) Bulbiferous Bladder-fern.
Family, Polypodiacee.

This fern grows on moist. rocks, especially limestone, and is easily cultivated
in greenhouses, where it propagates itself extensively.

Sporophyte.

1. Sketch a leaf showing a number of fleshy brood-buds (bulblets). On
which side of the leaf are they developed?

2. Under dissecting microscope draw a brood-bud which has just fallen off.

3. Draw a young fern plant which is developing from a brood-bud. Is this
an efficient method of vegetative propagation? Why?

(c) Marattia douglassii (Presl.). Order, Marattiales. Family, Marat-
tiacez.

This fern may be obtained in large greenhouses and conservatories. Use
either fresh or preserved material.

1. Draw a leaflet showing the peculiar sori. 2

2. Draw a single sorus under low power and describe. This is a eusporan-
giate fern. How do the sori and sporangia differ from those of Cyrtomium?

LXIII. Lycopodium lucidulum Mx. Shining Club-moss.

Phylum, Lepidophyta. Class, Lycopodiee. Order, Lycopodiales. Family,
Lycopodiacee. :

This lycopod grows in moist woods and on shady cliffs. Use fresh, alcoholic,
or herbarium material. |

Sporophyte.

1. Sketch the entire plant. Note the dichotomous branching, the alternating
zones of sporophylls and sterile leaves, and the dichotomous roots.

2. Draw a branch, showing very carefully the tip and several zones of sporo-
phylls below. Note that the formation of sporophylls does not stop the growth
of the axis on which they are produced. Which are the larger, sporophylls or —
sterile leaves?

3. Draw a single sporophyll with sporangium under low power.

4. Under high power draw several non-sexual spores.

58 LABORATORY OUTLINES FOR GENERAL BOTANY.

5. From alcoholic material cut cross sections of the stem, mount, and draw
under lower power. Note the epidermis with cuticle, the wide cortical layer, the
vascular bundles of the leaf traces, the bundle sheath or endodermis, and the
central cylindrical mass of vascular tissue. Inside of the endodermis are a number
of more or less parallel strands of xylem and phloem. These structures will be
more prominent after staining with iodin solution. This type of vascular system
is called a protostele. :

6. Cut radial longitudinal sections of the stem and compare in detail with the
cross section.

7. Vegetative propagation. Notice the peculiar bulb-like brood-buds near the
tips of some branches. Pick off one and draw under dissecting microscope.

LXIV. Lycopodium obsctrum L. Tree Club-moss.

Lycopodium obscurum grows in moist woods, forming long slender rhizomes
which creep under the surface of the ground or under leaf mold. From this
rhizome upright, erial branches develop.

Sporophyte.

1. Sketch an entire plant showing the rhizome and upright branch bearing —
a number of cones.

2. Draw a single cone under dissecting microscope. Note the spiral arrange-
ment of the specialized sporophylls, and that by the development of a cone the.
further development of the axis is stopped. What is the probable reason for this?

3. Under low power draw a single sporophyll showing the sporangium.
Note the advance in specialization of this sporophyll over that of the Dee
plant.

4. Under high power draw some of the nonsexual spores; also some of the
spore tetrads from younger sporangia.

5. Nore.— This cone represents a ree flower. Compare it with the
zone of sporophylls in the preceding species.

LXV. (a) Equisétum arvénse L. Field Horsetail.

Phylum, Calamophyta. Class, Equisetee. Order, Equisetales. Family, Equise-
tacez.

The field horsetail is common along roadsides and railways, on river banks
and steep slopes facing the north. The fertile branches come up in April and
May, while the sterile ones begin to appear at about the same time, but do not
reach their full development until later in the season. Spores may be collected
in large quantities and kept in a dry glass bottle. Rhizomes with fertile and
sterile branches should be preserved in 70 per cent. alcohol. Good herbarium
specimens may also be used.

Sporophyte.

1. Sketch a plant containing the rhizome, fertile shoot with cone, and young
sterile shoot. Note the whorls of scale-like leaves at the nodes; also the lack of
chlorophyll in the fertile shoot.

2. Sketch a mature sterile shoot.

83. Note and describe the division of labor in the stem of this plant — rhi-
zome for a food storehouse and for vegetative propagation, fertile branch for the
production of non-sexual spores, sterile branch with abundant chlorophyll for food

manufacture. From whence is the food material obtained which goes to form

LABORATORY OUTLINES FOR GENERAL BOTANY. 59

the fertile shoot? Compare the stems of Lycopodium lucidulum, L. obscurum and
Equisetum arvense and note the degree of differentiation in each.

4. Cut off some of the peltate sporophylls, mount and draw from the side
under dissecting microscope. Show the stalk, the angular outer expansion and
the sack-like sporangia hanging from the under side. How are the sporophylls
arranged in the cone? Compare this cone and the sporophylls with those of Lyco-
podium obscurum. Compare also these two sporophylls with a fern sporophyll.

5. Place a small flake of the dry spores on a slide without water or cover-
glass, breathe on them gently until the glass becomes moist, and examine imme-
diately under low power. Note the spores with appendages coiled about them.
In a few moments the spores will be-in violent agitation, while the appendages
uncoil. Breathe gently on the slide while looking into the microscope. How many
appendages on each spore? Draw. Describe in detail the hygroscopic prop-
erties of the appendages. Of what advantage to the plant is this peculiar ar-
rangement?

6. Cut cross sections of a young fertile branch from alcoholic material.
Mount, stain with iodin solution and draw under low power. Note the epider-
mis, the wide cortical layer with a circle of lysigenous cavities, the endodermis,
the circle of vascular bundles, and the pith with a large central lysigenous cavity.
The xylem (wood) of each vascular bundle is arranged somewhat in the form of
a V, the apex of the V being occupied by a large air-cavity. The two limbs of
the V end near the endodermis, and the phloem is situated between these two
masses of xylem.

(b) .Equisétum praealtum Raf. Scouring Rush.

This plant grows in wet places along the banks of rivers, creeks and lakes.

J. Examine the fresh or dry stems under low power. Notice the parallel
grooves and ridges, with lines of tubercles and stomata. Draw and describe.

2. Break some of the dry stems and note their brittleness. Burn one of
the stems in a hot flame, mount the outer part of the shell which remains, and
examine under low power. Notice that the cell walls and stomata are still distinct.
This is because the cell walls are impregnated with silica. Draw a flake showing
the stomata.

3. Note. — The cavities often contain water or ice in the winter.

SUB-KINGDOM, PTERIDOPHYTA HETEROSPORZ.
LXVI. Marsilea quadrifolia L. European Marsilea.

Phylum, Ptenophyta. Class, Hydropteride. Order, Marsileales. Family,
Marsileacee.

This water fern grows well in artificial ponds, in gardens and greenhouses.
The western Marsilea vestita H. & G. found in wet places and shallow ditches on
the great plains and prairies of the interior may also be used. The sporophytes
are mature in autumn.

Sporophyte. :

1. Sketch a branch of the creeping rhizome, showing the roots and the leaves
with slender upright petioles.

2. Sketch a sporophyll with two sporocarps.

3. ‘Carefully cut off part cf the thick inner margin of some sporocarps and
place them in a glass of water. In a day or two a gelatinous ring will be ex-

60 LABORATORY OUTLINES FOR GENERAL BOTANY.

truded on which are situated the sack-like sori in which mcrOspoT ne Sad mega-
sporangia are contained. Draw.

4. Mount some of the microsporangia and megasporangia and draw each.
under low power. The megasporangium contains a single megaspore; the micro-
sporangium a considerable number of microspores. The difference between the
microsporangium and megasporangium is the first indication of a sexual dimorphism
in the sporophyte; in the homosphorous plants, the sporophyte is entirely neutral
ii respect to sex. é

5. Under high power draw a single microspore and megaspore, in correct
proportion. |

Gametophyte.

6. In the meantime the spores will begin to develop the gametophytes. These
are very minute, and the spores in the water should be examined every few hours
in order to get the proper stages. The male gametophyte develops entirely inside
of the microspore wall and the female gametophyte merely protrudes the neck of the
archegonium (ovary) from one end of the spore. Draw a male gametophyte with
a protrusion on the side of the spore wall for the escape of the spermatozoids and
a female gametophyte with archegonium projecting from one end, showing a large
number of spermatozoids in the gelatinous substance extending from the neck of
the archegonium. Why does the microspore always give rise to a male plant, and
the megaspore to a female?

7. If prepared slides are at hand, study and draw sections of mature male
and female gametophytes. The male gametophytes correspond to the pollen grain
ct seed plants, and the female gametophyte to the embryo-sac in the ovule. Both
gametophytes of Marsilea must be compared with the hermaphrodite gametophyte
of Adiantum. Note especially the great reduction in size; also that after this there
will be no more hermaphrodite gametophytes, hence no possibility of self-fertiliza-
tion.

8. In a week or so the female plants in the glass of water will have embryo
sporophytes. Draw under low power and describe.

9. ‘EcotocicAL Note.— Examine a plant at night, or place a flower-pot with
a living plant in a dark chamber and note the manner in which the leaflets fold
up. How long does it take the leaflets to unfold after being placed in sunlight?

LXVII. Salvinia natans (L.). Salvinia.
Class, Hydropteride. Order, Salviniales. Family, Salviniacez.

This floating water fern grows readily in aquaria in greenhouses.

Sporophyte.

1. Draw an entire plant as it floats on the surface of the water, showing the
borizontal stem, the leaves, and the peculiar root-like leaves hanging down from
the underside.

2. Take out some of the plants and throw them into water. Note how they
nearly always turn right side up.

3. Place a leaf on the slide and examine without cover-glass andes low power.
Draw a part of the surface showing the peculiar hairs. What is their use?

Mount one of the dissected, root-like leaves and sketch under low power.

5. EcotocicAL Note. — Describe the various ways in which the sporophyte of
Salvinia is adapted to its enyironment,

Re Se

LABORATORY OUTLINES FOR: GENERAL BOTANY .. 61

LXVIII. Isdetes melanépoda J. Gay. Black-based Quillwort.
Phylum, Ptenophyta. Class, Isoetez. Order, Isoetales. Family, Isoetacaee.

This quillwort may be found in moist prairies and overflowed fields in the
central states of the Mississippi Valley. Fresh or herbarium specimens may be
used, and stems preserved in 70 per cent. alcohol.

— Sporophyte.

1. Sketch and describe the entire sporophyte, showing leaves, short stem, and
roots.

2. Study prepared slides or cut cross sections of stems in alcohol and draw,
showing the following structures: the two vertical furrows and two large lateral
lobes, the outer cortex and extensive parenchymatous tissue in which the cells are
arranged in radial rows, on the inner limits of this layer a zone of meristematic
cells, inside of this a layer of clear cells (the phloem, “prismatic layer”) and in the
center a xylem-cylinder from which bundles pass outward to the leaves.

LXIX. Sigillaria sp.

Phylum, Lepidophyta. Class, Selaginellee. Order, Sigillariales. Family,
Sigillariacez.

Fossil impressions of the trunks of large, arboreous Sigillarias are common
in the formations of the carboniferous period and may be seen in most museums.

1. Sketch the surface of part of a trunk of Sigillaria, showing the leaf scars

and the longitudinal fluting.

2. Notre.— The heterosporous pteridophytes of the present time are the rem-
rants of a once great group of plants which formed a characteristic vegetation be-

tore and during the carboniferous period, which ended millions of years ago.

LXX. Selaginélla kraussiana (Kunze.) Krauss’ Selaginella.

Phylum, Lepidophyta. Class, Selaginellee. Order, Selaginellales. Family,
Selaginellacez.

This plant grows very luxuriantly in greenhouses and window gardens, if the
soil is provided with proper moisture. Suitable material may be had at any time
of the year.

Sporophyte.

1. Sketch an entire plant, showing branches, leaves, and roots. Note that
the branches occur only in one plane and that the roots are dichotomous. Describe
the character and arrangement of the leaves. How do you account for the arrange-
ment? How does the plant accomplish vegetative propagation ?

2. Draw a leaf under low power. Under high power draw a cell, with a single
chloroplast and one with several chloroplasts. Draw also one of the stomata.
Where are the stomata situated? Look for the ligule on the leaf. Of what use
is the ligule?

3. ‘Cut cross sections of a fresh stem or of stems preserved in alcohol, mount,
and draw, representing the following structures: ‘epidermis, cortical tissue in which
may appear sections of bundles passing to the leaves, two or more large air spaces,
and in the center of each space a vascular bundle. The bundle consists of a central
strand of xylem (wood) surrounded by a band of phloem which is enclosed in a
large-celled bundle sheath. Note the strands of cells passing through the air space
from the cortex to the vascular bundle.

4. Draw one of the short bisporangiate cones (primitive flower) under dissect-
ing microscope, showing microsporophylls above and one or more megasporophylls
below,

62 LABORATORY OUTLINES FOR GENERAL BOTANY.

5. Carefully pick off a microsporophyll and a megasporophyll each with its
sporangium, mount and draw under low power. Note the greater specialization
in the arrangement of the sporangia over that of Marsilea. How many mega-
sporophylls in comparison with the microsporophylls on each cone? Note the
numerous microspores in the microsporangium. How many spores in the mega-
sporangium ?

6. Draw a microspore and a megaspore in exact proportion under low power.
How do you explain this difference in size of the nonsexual spores? Determine
how many times greater in volume the megaspore is than the microspore. How
many megaspores and microspores in one cone?

Gametophyte.

7. From prepared slides draw the male and female gametophytes of Selaginella,
the archegonium (ovary) and antheridium (spermary) and the oosphere and
spermatozoid. Why does the microspore always produce a male and the megaspore

Fic. 14— Lire Cycle oF SELAGINELLA,

a female gametophyte? Compare with Note 12 under Vaucheria. Observe also
that the determination of sex in these plants, as well as all other heterosporous
groups, has no relation to the reduction division.

8. Draw and describe a young sporling showing root, stem and first leaves
with megaspore still attached containing the female gametophyte and foot of the
sporophyte.

9. Make a diagram in the notes showing the life cycle of Selaginella. See
Pig.14,.: ©:

10. Notre.—It will be remembered that in the lowest archegoniates the
gametophyte is the important plant in the life cycle, and that the sporophyte is
very small. Now in the highest forms the tables are turned and the sporophyte
has become the plant. Between such plants as Isoetes and Selaginella on the one
land and the lowest living seed plants on the other, there is a considerable hiatus,
nevertheless it is not difficult to trace the transformation which was necessary in
passing from the condition of heterosporous pteridophytes to the lowest gymmo-
sperms, because numerous intermediate fossil plants haye been found, |

LABORATORY OUTLINES FOR GENERAL BOTANY.

Pew SU bea yY EA, CLASSES: AND: SUBCLASSES: OF PLANTS.

Phylum I. ScuizopHyrta. Fission Plants.
Class 1. Cyanophycee. Blue-green Alge.
Class 2. Glaucocystee. Higher Blue-green Alge.
Class 3. Schizomycete. Fission Fungi.
Class 4. Myxoschizomycete. Slime Bacteria.
Phylum IJ. Myxopuyta. Slime Fungi.
Class 5. Acrasiez.
Class 6. Myxomycete. Slime Molds.
Subclasses.
a. Ceratiomyxee.
b. Myxogastere.
Phylum III. ZycopHyta. Conjugate Alge.
Class 7. Diatomez. Diatoms. (Subphylum A).
Class 8. Conjugate. Conjugates. (Subphylum B).
Phylum IV. GonipiopHyTA. Zoospore Plants.
Class 9. Autospore.
Class 10. Plasmodiophoree. Clubroot Fungi.
Class 11. Archemycete. Primitive Fungi.
Class 12. Chlorococcee. Green-slimes.
Class 18. Hydrodictyee.
Class 14. Siphonocladee. Lower Tube Algz.
Class 15. Siphonee. Higher Tube Algz.
Class 16. Monoblepharidez.
Class 17. Confervez. . Confervas.
Phylum V. PHaropHyta. Brown Alge.
Class 18. Phaeospore. Kelps.
Class 19. Cyclospore. Rockweeds.
Class 20. Dictyotez.
_ Phylum VI. RuHopopHyta. Red Alge.
Class 21. Monospore.
Class 22. Floridee. Red Seaweeds.
Phylum VII. CHaropHyta. Stoneworts.
Class 23. Charec.
Phylum VIII. Mycoppyta. True Fungi.
Subphylum A. Phycomycetae. Algal Fungi.
Class 24. Zygomycete.
Class 25. Oomycete.
Subphylum B. Mycomycetae. Higher Fungi.
Class 26. Ascomycete. Sack Fungi.

Subclasses.
a. Hemiasce. Intermediate Sack Fungi.
b. Exoasce.
c. Aspergillee. Tuber Fungi.
d. Discomycete. Disk Fungi.
e. Pyrenomycete. Black Fungi.
f. Deuteromycete. Imperfect Fungi.

Class 27. Laboulbeniee. Beetle Fungi.
Class 28. Teliospore. Brand Fungi.

63

‘Subetases eat ne
Soren ee
x mn

Class” 31. Soha oe t
Class 32... Schizocarpe. — sranite M
Class 33. Musci. True -Mosses. :
Class 34. Anthocerote. — Hornworts.

Phylum X._ PTENOPHYTA, — Fe ernworts
Class 35. Filices. Ferns.
ae oe

: - Eusporangiate. Prin litive ‘Ferns.

a 4 _Leptosporangiate. Modern Fe rns.
Class 36. Hydropteride. — Water-ferns. eee
Class 37. Isoeteze. Quillworts.

Phylum XI. CaraMopHytTa. Calamite Plants
Class 38. Sphenophyllez. — (Fossil). Wedge-te
Class 39. Equisetez. ‘Horsetails. iS ;

Class 40. Calamarie. (Fossil). Galante...

Phylum XII. Lepmopwyta. Scale-leaf Plants. —
Class 41. Lycopodiez. — Lycopods. eS ye
Class 42. Selaginellee. Selaginellas =

Phylum XIII. Cycapopyta. Cycad Plants. ~ ge
Class 43. Pteridosperme (Fossil). Seed Ferns. Sat ee
Class 44. Cycadee. Cycads. ; eee ae
Class 45. Cordaiteee (Fossil). Cee Sa ee

‘pe Slass 46. Ginkgo. Maiden-hair-trees. q Oe ee

Phylum XIV. Srrosrropuyra. Strobilus Plants. NS ea
Class 47. Conifere. Conifers. - ee ee 2
Class 48. Gnetez. Joint-firs. GAO eee

Phylum XV. AntHopHytTa. Flowering Plants.’
Class 49. Monocotyle. Monocotyls.

Subclasses. z >
a. Helobize. ae ea
b. Spadiciflore. s
-c. Glumiflore.
d. Liliflore.
Class 50. Dicotyle. Peon
Subclasses.
a. Thalamiflore.
b. Centrosperme. — a.

c. Calyciflore. ; A $
d. Amentiferze. eo Sa
e. Myrtiflore. -

{. .Heteromere.

g. Tubiflore.

h. Infere.

SERIES III — SPERMATOPHYTA.

SUB-KINGDOM GYMNOSPERM-.
exch -Cycas revoluta I~ Cycad.

Phylum, Cycadophyta. Class, Cycadee. Order, Cyadales. Family, Cycadacez.

This plant is usually grown in greenhouses and conservatories. Herbarium
and museum material should also be at hand.

1. Examine a living plant and describe its general character. Sketch the stem,
showing the scale leaves and one foliage leaf.

2. Draw a megasporophyll (carpel) from herbarium specimens, showing the
megasporangia or ovules. Note the similarity of the carpel to the foliage leaves
The carpels are produced in a whorl like the foliage leaves, and the stem continues
to grow thru the whorl. Compare this condition with the ordinary ferns and with
Lycopodium lucidulum,

3. Make a sketch of the large staminate (microsporangiate) cone. Draw a
single microsporophyll (stamen), showing the numerous microsporangia on the
under side.

4. From alcoholic material draw a young ovule, properly dissected, showing
the integument with micropyle, the inner wall of the ovule (megasporangial wall)
with the pollen chamber, and the female gametophyte.

5. Draw half of a large female gametophyte from a mature seed, showing
the little depression at the outer end and the dormant sporophyte embryo. The
necks of the archegonia open into this depression (called the archegonial chamber )
ai the time of fertilization.

6. Mount male gametophytes (pollen-grains), and draw under high power.

7. If prepared slides are available study sections of pollen-grains showing
the internal structure.

8. Note.— The fundamental difference between the heterosporous pterido-
phytes and the lower seed plants is that in the latter the microspores and mega-
spores are not shed, but develop the male and female gametophytes in the micro-
sporangia and megasporangia respectively, while in the former the spores sooner
or later drop to the ground. The female gametophyte remains permanently en-
closed in the megasporangium, but the male gametophytes are shed from the
microsporangia and some fall into the micropyle of the ovule. This is known as
pollination. In order that the spermatozoids may fertilize the oospheres in the
archegonia a short pollen tube must grow thru the tissue between the pollen
chamber and the female gametophyte. It will be observed that the gametophytes
are now entirely parasitic, the female in the ovule and the male at first in the
microsporangium, and after pollination, in the wall of the ovule.

LXXII. Ginkgo biloba L. Maiden-hair-tree.

Phylum, Cycadophyta. Class, Ginkgoe. Order, Ginkgoales. Family, Gink-
goacee.

This beautiful tree, a native of China and Japan, is cultivated quite exten-
sively in the United States. Museum and herbarium material may be used.

: | (65)

66 LABORATORY OUTLINES FOR GENERAL BOTANY.

Sporophyte.

1. Sketch a leafy branch, showing the leaves developed in clusters on dwarf —
_ branches. Note that dwarf branches may give rise to ordinary branches.~

2. Sketch a single leaf under dissecting microscope, showing the dichotomous
venation. ‘Compare the venation with that of the Adiantum leaf.

3. Sketch a stamen (microsporophyll) under lower power. How many
microsporangia? ‘Compare with stamen of Cycas. Sketch a carpel (menesRaea:
phyll) and compare with the Cycas carpel.

4, Sketch a mature fleshy seed on its long stalk. Note the collar or cup
around the base of the seed and the small undeveloped ovule. On some stalks
two seeds develop. Remove the fleshy part of the integument and note the hard,
inner layer.

Gametophyte.

5. Draw a male plant (pollen-grain) under high power.

6. From alcoholic material study the mature female gametophyte (kernel of
the seed). Sketch, and compare the size of the male and female gametophytes.

7. Carefully cut longitudinal sections from one side of the female gameto-
phyte until the embryo sporophyte comes into ‘view, and sketch the section under
dissecting microscope, showing the embryo in position.

LX XIII. Conifers. General Study.

Phylum, Strobilophyta. Class, Conifer. Order, Pingles:
The conifers called for below are cultivated quite extensively, and material
for study can usually be obtained without difficulty.

(a) Various Conifers. :

Collect branches of the following: Pinaceae— Norway spruce (Picca abies
(L.), Canadian hemlock (Tsiga canadénis (L.), European larch (Larix larix (1.).
Juniperacee — arborvite (Thitja occidentalis L.)

1. Sketch a short branch of the Norway spruce and note a slight tendency
t> bilateral symmetry, and how the leaves are bent from the under side to obtain
a proper light relation. ;

2. Sketch a branch of the Canadian hemlock with carpellate cone at the end.
Note bilateral arrangement and the light relation of the leaves, especially the small
ones on the upper side.

3. Sketch the larch branch showing the large vant branches. Compare
with Ginkgo. Note that the foliage leaves are deciduous annually, and that the
dwarf branches may. develop into ordinary branches. Are the dwarf branches
deciduous (self-pruned) ?

4. Sketch a small branch of the arborvite. Note the flattened condition of
the stem and the leaves. Note also that numerous branches of various sizes are ~
self-pruned. '

(b) Pinus. Family, Pinacee.

Collect large branches of white pine (Pinus strobus L.) pitch pine (P. ylgide
Mill.) Austrian pine (P. laricio Poir.), and Scotch pine (P. silvéstvis L.) Also
collect the dwarf branches with needle-leaves which have been self-pruned.

1. Study and sketch a branch of the Austrian pine, showing scale leaves,
dwarf branches, and foliage leaves (needles). How old is the branch studied?
What two ways of telling the age? Are the foliage leaves.deciduous? How old
are the dwarf branches before they are self-pruned? Where do the ordinary ©
branches originate, and when?

LABORATORY OUTLINES FOR GENERAL BOTANY. 67

2. Draw a dwarf branch, with scale leaves and foliage leaves, of the white
pine, pitch pine, Austrian pine, and Scotch pine. Note the peculiarities of each
dwarf branch. Compare with Larix and Ginkgo.

3. Under low power, without cover-glass, draw part of the foliage leaf of
the Austrian pine, showing the stomata. How are they arranged? Draw a scale
leaf from the ordinary branch and one from the dwarf branch. Note the
difference between the foliage leaves and the scale leaves.

4. Cut cross sections of a foliage leaf, mount and study under low power.
Draw and note the following tissues: epidermis with sections of the stomata,
heavy-walled hypodermal tissue, green mesophyll with a number of resin-ducts,
a limited layer of large clear cells, and the light-colored central region with two
vascular bundles. 3

(c) Structure of White Pine Stem.

Preserve pieces of branches, one to six years old, in alcohol, and also obtain
large, polished cross sections (about two inches thick) of a tree-trunk with bark.

1. With a strong, sharp razor, cut cross, tangential and radial sections of
stems in alcohol, mount, and stain with iodin; or study prepared slides.

2. Draw part of a cross section under low power, showing epidermis, cortex,
with resin passages, phloem, cambium, xylem in a number of annual rings with
medullary rays and resin passages, and central pith.

53. Radial section. Draw under low power, showing cortex, cambium, xylem
(composed of the tracheids), and pith. Note the medullary rays passing from the
pith to the phloem. | .

4. Tangential section. Draw under low power, showing part of the xylem
with tracheids and cross sections of the medullary rays.

5. Under high power draw part of a tracheid from radial section, showing
the peculiar bordered pits.

6. Sketch part of a polished section of an old pine stem, showing bark,
cambium, sap wood, heart wood, and pith. Notice the medullary rays. Notice
also that each annual ring of wood is double — early wood and late wood. On
which side is the early wood? Describe the growth of a pine tree in height and
thickness.

(d) Sporophylls of Pinus laricio.

Use fresh or alcoholic material.

1. Draw a staminate (microsporangiate) cone under dissecting microscope.
Describe the arrangement of the stamens (microsporophylls).

2. Draw a stamen under low power, showing the outer (under) side with
two microsporangia (pollen-sacs). How different from the microsporophyll of
Selaginella in structure and function?

- 3d. Draw a young carpellate (megasporangiate) cone under dissecting micro-
scope. Describe. Note that the parts are smaller at the lower end.

_4. Draw a carpel (megasporophyll) from the lower side under low power,
showing the bract (true leaf blade of the carpel) and the large ovuliferous scale.
This may be an outward growth of the chalazal region of the ovules. Draw the
carpel from the inner (upper) side, showing the two ovules (megasporangia) and
the ovuliferous scale. Compare the carpel with the megasporophyll of Selaginella.

5. Draw a mature carpellate cone. Note the spiral arrangement and that

the carpels at the base are undeveloped and contain no seed. This is an example

of rudimentary organs. If a rudimentary organ was formerly more highly
developed and functional it is called a vestigial organ or a vestige.

68 LABORATORY OUTLINES FOR GENERAL BOTANY.

6. Norre,— The staminate and carpellate cones of the pine represent primitive
flowers. Are these flowers monosporangiate (one kind of spores in the flower)
or bisporangiate (both kinds of spores in the same flower)? Compare with the
cone in Selaginella. Is the pine tree (sporophyte) monecious or diecious? —

(c) Carpellate Cone of Larix larix (L.).

Collect carpellate cones of the usual type and some which have the tip
continued as a leafy branch. Preserve in alcohol.

1. Sketch a normal cone in which terminal growth has been completely
checked. ie

2. Sketch a cone on which a leafy branch has developed at the outer end.
Note the gradual transition from carpels to ordinary foliage leaves. Sketch a
number under dissecting microscope, showing this transition. This continued
growth or prolongation of the floral axis of the larch cone is a good’ example of
reversion to a more primitive condition or atavism. Compare with the ordinary
ferns, Lycopodiwm lucidulum, and Cycas. a

3. Observe fresh or dried, young cones and note the presence of a special
color. How do you account for the color in this cone?

(f{) Gametophytes and seed.

The gametophytes of Pinus laricio may be studied from staminate and car-
pellate cones preserved in alcohol. The seeds may be kept in a dry condition.

1. Draw a male gametophyte (pollen-grain). Under high power. Note the
two wings. These represent an adaptation for anemophilous pollination.

2. Remove the female gametophyte from a young seed (collected at the
time of fertilization, about July 1), and draw under dissecting microscope. Note
the difference in size between the male and female gametophytes. Compare the
two gametophytes with those of Marsilea and Selaginella.

3. Draw a mature seed. Remove the testa and the inner seed coat. What
does the inner coat represent? Draw the female gametophyte. Carefully cut out
the embryo sporophyte, which is now in a dormant condition. Sketch under dis-
secting microscope, showing the radicle, suspensor and cotyledons. Pick off the
cotyledons from one side and sketch the plumule. How many cotyledons? Instead
of P. laricio, the seeds of Pinus édulis Engelm, the nut pine of commerce may be
used to advantage.

4. If prepared slides are at hand draw a section of a stamen, showing the
one-celled microspores.

5. Draw a section of a male gametophyte (or study mature pollen-grains
preserved in alcohol) showing the large tube cell and nucleus, the generative cell
and the two disorganized vegetative cells lying like two thin plates against the
wall of the grain back of the generative cell.

6. Draw a section of a young ovule, showing the functional megaspore.

7. Draw a pollen-grain which has formed a short pollen-tube growing down
into the nucellus (tip of the megasporangium). Note the tube nucleus in the
tube and in the body of the grain the spermatogenous cell, the stalk cell and the
remains of the two evanescent vegetative cells. The spermatogenous cell divides
later into two sperm cells which do not have flagella or cilia. From the same
section draw the spherical embryonic female gametophyte. ©

8. Draw a female gametophyte showing archegonia (ovaries) with oospheres,

9. Draw an archegonium (ovary) in which the nucleus of the oosphere has

divided into four nuclei.

° LABORATORY OUTLINES FOR GENERAL BOTANY. 69

10. Draw the upper part of a female gametophyte, showing remains of arche-
gonia with an elongated cavity below them in which appear a number of embryos
in various stages of development. Only one of these embryos survives, probably
the one which has a slight advantage in size, vigor, and food supply. Note the
struggle for existence which must go on among these embryos.

11. Sketch a mature seed, showing the wing. Let a winged seed drop to the
floor from a height of six or seven feet and note how it falls. Describe the adapta-
tion this seed has for dissemination. Note also the readiness with which the seed
is separated from the wing. Of what use is this adaptation?

Fic. 15 — Lire Cycte or PINE.

(¢) Seedlings and Primitive Leaf Arrangement.

Plant seeds of Pinus and Thuja accidentdlis and use fresh plantlets or pre-
serve in alcohol. Also obtain branches of the common juniper (Juniperus com-
mums L. Family, Juniperacee) and cultivated varieties of Thuja known as
retinispora forms. In these retinispora or juvenile forms, branches often change
suddenly from the form with spreading leaves to the flattened condition, and the
fiattened branches again revert to the form with spreading leaves.

1. Sketch a pine seedling which has sprouted, showing the seed coat still cover-

- ing the cotyledons. Sketch a seedling with cotyledons expanded. Describe the im-
portant changes which take place in the embryo during the process of sprouting.

2. Sketch a branch of Juniperus commums and note that all of the leaves
are of the spreading type.

3. Study and sketch the seedings of Thuja occidentalis and note that at first
the leaves are of the spreading type much like those of Juniperus, and that later
the branches have the flattened form characteristic of the adult plant. Apply
the recapitulation theory as given in connection with the moss protonema. From

70 LABORATORY OUTLINES FOR GENERAL BOTANY. Cee

this it would appear that the ancestors of Thuja had the leaves arranged like
those of the common juniper. . .

4. Study and draw a small branch of Thuja or Chamaecyparis (retinispora
form), in which the upper part of a flattened branch has changed back to the
juvenile form. In such cases there is a second reversion. In other words, the
branch takes on first one form and then another successively.

5. Make a diagram showing the life cycle of a pine. See Fig. 15. Compare
with Figs. 9 and 2.

6. Nore on the development of the carpellate pine cone.

The young carpellate cones of Pinus laricio begin to develop in the bud
during the summer or fall, and in the following spring the carpels have young
ovules with a distinct integument. Later (about the middle of May) the ovules
are pollinated and the megaspore is developed. In the following autumn (Octo-
ber) the megaspore has germinated and the female gametophyte is developing as
a hollow spherical body composed of free, naked cells. It passes the winter in
this condition. In June of the following year the archegonia with eggs are ready
for fertilization and the pollen-tubes have grown down thru the nucellus. About
the last week in June or the first in July fertilization occurs, and the embryo is
matured and in the resting condition in the following autumn. The seed is usually
shed late in the winter or in the early spring of the year following. The whole
history thus covers nearly three full years. , <

“TEX Taxus canadensis Marche Ammecie nn ae

Phylum, Strobilophyta. Class, Conifere. Order, Taxales. Family, Taxacez.

The yew is a low shrub growing on moist banks and hills, especially in the
shade of large conifers. It is common northward. Herbarium and alcoholic
material may be used if fresh branches are not available.

1. Sketch a branch, showing arrangement of leaves. Describe.

2. Under dissecting microscope draw a staminate cone. How are the stamens
arranged?

3. Draw a single stamen under low power and note the peltate form. How
many microsporangia? Compare the shape of this stamen with the sporophyll of
Equisetum.

4. Under dissecting microscope draw a small fertile branch with a young
ovule at the tip.

5. Cut longitudinal sections of the branch with ovule, mount, and draw
under low power, showing the megasporangium in the center surrounded by the
long inner integument and a short outer undeveloped aril, with scale-leaves on
the stem below.

6. Draw a ripe seed with the thick, fleshy, red aril. Compare the aril with
the ovuliferous scale of Pinus.

LXXV. Higher Gymnosperms.

Phylum, Strobilophyta. Class, Gnetee.

Study herbarium specimens.

1. Make a sketch of a small plant of Ephédra Sp. (Order, Ephedrales.
Family, Ephedracee). Note the slender green stems and the dry scale-leaves.
In what ways is this plant adapted to a xerophytic environment?

2. Make a sketch of a branch of Gucetum gnémon L. (Order, Gnetales.

Family, Gnetacee). Note the large broad leaves. This is a tropical tree cul-
tivated in India and surrounding regions,

LABORATORY OUTLINES FOR GENERAL BOTANY. 71

SUB-KINGDOM, ANGIOSPERM.

A NUMBER OF FORMS TO REPRESENT THE GENERAL EVOLUTION OF THE FLOWER IN
MONOCOTYLS AND DICOTYLS.

Along with this series of outlines on the Anthophyta, the student should be
given work in identification with a key and several periods can profitably be spent
in analyzing and making diagrams of various spring flowers.

LXXVI. Magnélia sp. Magnolia. Phylum, Anthophyta. Class, Dicotyle.
Grder, Ranales. Family, Magnoliaceze.

The magnolias are among the most primitive of the Anthophytes. Any of
the native or cultivated species will have suitable flowers in early spring. They
may be used fresh or preserved in alcohol.

Sporophyte.

1. Sketch the entire flower; describe size, color, etc. Note the character of
the stem. Compare the flower with the cones of Lycopodium, Eaquisetum, Selagin-
ella, and Pinus. ;

2. Sketch a sepal, a petal, a stamen and a carpel; describe each organ. The
stamen is a microsporophyll and the carpel a megasporophyll.

3. How many sepals in the calyx? How many petals in the corolla? How
many stamens in the andrecium (stamen set)? How many carpels in the gyne-
cium (carpel set)? How many cycles in the perianth? Note especially that the
stamens and carpels are arranged spirally. Compare several flowers as to the
constancy or variability in number of parts. Make a diagram of the flower. See
Fig. 17a.

LXXVII. (a) Sagittaria latifolia Willd. Arrow-head.

Phylum, Anthophyta. Class, Monoctyle. Order, Alismatales. Family, Alis-
matacee.

The broad-leaf arrow-head grows in moist ground on the margin of ponds,
creeks and canals and blooms in summer. If fresh material is not available,
good herbarium specimens may be used. Flowers and other parts may also be
preserved in alcohol.

Sporophyte.

1. Sketch and describe the entire plant, noting the character of the leaves,
stem, roots and inflorescence.

2. Sketch the staminate flower, showing sepals, petals and stamens. How
“many parts in each set? Find the vestigial carpels. Draw one under dissecting
microscope. _ gi ;

3. Sketch the carpellate flower and describe the parts present. What parts
of the two flowers are cyclic and what parts eee in arrangement? Is this
sporophyte monecious or diecious?

4. Under dissecting microscope draw a sepal, a petal, a stamen (microsporo-
phyll) and a carpel (megasporophyll). Compare the normal carpel with a vestigial
carpel. How did this plant attain the monecious condition?

5. Cut cross sections of a young stamen, mount, and draw under low power.
How many microsporangia? Note that the stamen is made up of anther and
filament.

6. Cut off one side of a carpel so as to expose the ovule (megasporangium).
Draw under low power, showing the stigma, short style, and ovulary. Note

IZ LABORATORY OUTLINES FOR GENERAL BOTANY.

that the stigma is a new organ not present in any of the Gymnosperms. Why is
the stigma necessary to this carpel?

(b) Rantnculus abortivus L. Crowfoot.

Phylum, Anthophyta. Class, Dicotyle. Order, Ranales. Family, Ranuncu-
lacez. .

This plant is common in April and May along brooks, on hillsides, in
meadows, and along roads.

Sporophyte.
1. Sketch the entire plant, showing the various organs.
2. Sketch the flower and describe the condition of the four sets of floral

organs. Note that the flower is bisporangiate. Compare with the cone of Sela-

ginella.
3. Draw a sepal, a petal, a stamen, and a carpel under dissecting microscope.

LXXVIII. Alisma subcordatum Raf. Water Plantain.

Class, Monocotyle. Order, Alismatales. Family, Alismatacez.

The water plantain is common in wet and muddy places, on the margin of
ponds and creeks and blooms in summer. Herbarium specimens and preserved
material may be used.

Sporophyte.

1. Sketch a leaf-and a part of the inflorescence.

2. Sketch a flower showing the four sets of floral organs —calyx, corolla,
andrecium and gynecium. How many sepals, petals, stamens and carpels? Are the
parts spiral.or cyclic? Free or united? Is the flower monosporangiate or bisporan-
giate? Note that the flower is hypogynous. What advance does this flower show
over that of Sagittaria or Ranunculus?

3. Make a diagram of the flower. See Fig. 17b.

4. Cut cross sections of the stamens or use prepared slides and draw under
low power. How many microsporangia (pollen-sacs)? Cut open the ovulary and
dissect out the ovule (megasporangium). Draw.

5. From prepared slides draw a microsporocyte and a microspore, showing
the nucleus, cytoplasm and wall.

6. From prepared slide draw a young ovule, showing the funiculus, the integ-
uments, the megasporangium proper (nucellus), and the single megaspore. Note
the absence of a wall around the megaspore. Why not present?

Gametophytes.

7. From prepared slide draw a male gametophyte (pollen-grain), showing
the tube nucleus and the two elongated sperm cells.

8. From prepared slide draw an eight-celled female gametophyte (embryo-
sac), showing the three antipodal cells, the two polar nuclei, the oosphere, and
the two synergids. The oosphere and the two synergids are called the egg-
apparats (ovary). 2

9. From prepared slide draw a mature, seven-celled female gametophyte,
showing the fertilization of the egg and the conjugation of the polar cells to
form the definitive cell. Look for the conjugation of the second sperm with the
polars (triple fusion).

LABORATORY OUTLINES FOR GENERAL BOTANY. 73

10. From a prepared slide draw an embryo-sac with endosperm cells, which
have come from the division of the definitive cell, and with young embryo, con-
sisting of the embryo proper, the suspensor cells and the large, vesicular, basal,
suspensor cell. Note that the conjugation of the polar cells and the subsequent
development of the endosperm are entirely new phenomena, nothing similar being
known in plants below the anthophyta. In many other anthophyta the second
sperm cell from the pollen-tube comes down and unites with the polar cells pro-
ducing a triple fusion, as in Alisma.

“ll. Carefully remove a mature embryo from the seed and shetch under low
power, showing the single cotyledon, the lateral plumule and the radicle.

ay

Fic. 16.— Lire CYCLE oF ANGIOSPERM (ALISMA.)

12. Note that in this plant the seed remains in the ovulary, i. e. the fruit
-is indehiscént. Make a diagram showing position of the carpel wall, the integu-
ments of the ovule, the endosperm and the embryo. Note also that the ovule is
first orthotropous, then anatropous and finally campyllotropous.

13. Sketch a young seedling.

14. Make a diagram in the notes showing the general life cycle of an an-
giosperm. See Fig. 16. Compare with Figs. 9 and 2 (38a and 4a—3b and 4b—

LXXIX. (a) Sédum acre L. Wall-pepper.

Class, Dicotyle. Order, Saxifragales. Family, Crassulacee.

Many of the sedums grow well in greenhouses and in window gardens. They
usually bloom abundantly in the spring and the above or any other paceivs will be
found suitable.

1. Make a careful drawing of the flower and describe the character o the
different parts.

74

4.
above.

(b)

LABORATORY OUTLINES FOR GENERAL BOTANY.

Make drawings of the calyx, the corolla, the andrecium and the eyncrians Rese
Answer the following questions correctly:

Is the flower hypogynous, perigynous, or epigynous?

Is it tetracyclic or pentacyclic?

Are the circles or whorls trimerous, tetramerous or pentamerous?
Are the organs of any whorl or set united or partly united?
Is the flower isocarpic or anisocarpic?

Is it actinomorphic, isobilateral, zygomorphic, or unsymmetrical?

Make two diagrams showing the true condition of the flower as learned
See Fig. 17 c and d.

Chimaphila maculata (L.). Pursh. Spotted Wintergreen.

Class, Dicotyle. Order, Ericales. Family, Pyrolacee. ;
A low evergreen perennial growing in dry woods and blooming from May
to August. If fresh material is not available, use plants preserved in alcohol and
herbarium specimens. ;

1

Study the flower and note that it is pentacyclic and peniaeron ae typi-

cal dicotyl. Compare with Sedum. Note difference in arrangement of andrecium.

2. Note that the five sepals are united at the base; the five petals are separate
or slightly grown together at the base; the stamens are 10, denoting two cycles;
and the five carpels form an ovulary with five cavities (quinquelocular).

3. Note peculiarities in dehiscence of the anthers and the pollen. |
4. Note also that the flower is hypogynous, bisporangiate, aclinomossaa
isocarpic.

5. Notice the mottled leaves and their ability to endure the cold of “winter.

LXXxX. Trillium grandiflorum (Mx.). Large-flowered Trillium.

Class, Monocotyle. Order, Liliales. Family, Liliacez.
The large flowered Trillium grows in rich woods and blooms in April and

May.

ils

Make a sketch of the entire plant, showing the flower, leaves, and short

tuberous rhizome with contractile roots below. How deep was the rhizome under
ground? Describe how it descends into the earth. This plant is a geophilous,
herbaceous perennial. What are the advantages of the geophilous habit?

2.

Cut a cross section of the compound ovulary, mount, and draw under low

power, showing the cavities with ovules.

3.

Describe the condition of the flower according to the questions asked

under Sedum acre. Make a diagram of the flower. See Fig. 17e.

[DP @. 4 & Cypripédium parviflérum Salisb. Yellow Lady’s-slipper.

Class, Monocotyle. Order, Orchidales. Family, Orchidaceze.
This lady’s-slipper grows in wet places and low woods, and blooms in May
and June. Any other species will do as well.

1.

9

a.

Sketch part of a plant, showing the flower and part of the leafy stem.
Cut cross sections of the ovulary, mount and draw. How many carpels?

Study the flower with the aid of the diagram, Fig. 17f.

3.

Copy the diagram in the notes and write a general description of the

flower, noting especially that it is organized on the same plan as the Trillium
flower, that some of the parts have disappeared, that it is epigynous and zygo--

LABORATORY OUTLINES FOR GENERAL BOTANY. 75,

“morphic, that certain parts are united, and that is is highly specialized for insect

pollination.

4, Why should this flower be placed higher than any of the monocotyls. pre-
viously studied? Make a comparison of the flowers of Sagittaria, Alisma, Trillium

and Cypripedium.

LXXXII. Catalpa speciosa Warder. Hardy Catalpa.

Class, Dicotyle. Order, Scrophulariales. Family, Bignoniaceze.
The Catalpa is cultivated extensively and blooms abundantly in May and June.
1. Study the large compound panicle and draw a single flower.

Fic. 17. — DIAGRAMS OF FLOWERS.

2. Describe the flower carefully, noting the condition of each floral set and
whether the flower is hypogynous or epigynous, whether actinomorphic or zygo-
morphic. What adaptations for insect pollination? Note especially the rudi-
mentary or vestigial stamens. Be careful to distinguish vestigial organs (vestiges)
from incipient organs (incepts) and from nascent organs.

3. Cut cross sections of the ovulary, mount, and draw. How many carpels
in the gynecium?

4. Make two diagrams of the flower, showing transverse and longitudinal
arrangement.

LXXXIII. Cérnus fémina Mill. Panicled Dogwood.

Class, Dicotyle. Order, Umbellales. Family, Cornacez.
This common shrub usually forms thickets, in forests and on hillsides. It

76 LABORATORY OUTLINES FOR GENERAL BOTANY.

blooms in June, producing an abundance of flowers. Any other species with
panicled flowers will do.

1. Sketch the entire ieee ee and note the arrangement of the numerous
small flowers.

2. Under dissecting microscope draw a single flower. How many cycles?
How many stamens, petals and sepals? Note the minute size of the calyx.

3. Cut cross section of the ovulary. Draw under low power. How many
carpels? Note that the flower is epigynous.

4. Compare this inflorescence with that of the flowering dogwood, Cynoxylon
floridum (L.) noting especially the origin and nature of the white involucre.

5. Make a transverse and a longitudinal diagram of the flower. See Fig.
lie and *h-: :

LXXXIV. Ageratum conyzoides L. Ageratum.

Class, Dicotyle. Order, Compositales. Family, Helianthacee.

Ageratums are annuals which bloom all summer and are much used for
borders. The flowers may be had in the green house at any time of the year. The
plants will live and bloom for a long time.

1. Sketch one of the heads under dissecting microscope, showing the bracts
of the involucre and the numerous small tubular flowers.

2. Under dissecting microscope draw a single flower. What is the condition
of the pappus? What does the pappus represent?

3. Dissect the flower and draw the corolla and andrecium cad the gynecium —

under dissecting miscroscope or low power. Describe the flower and its parts in
detail.

LXXXV. Chrysanthemum leucanthemum L. Ox-eye Daisy.

Order, Compositales. Family, Helianthacee.

This plant grows in fields and meadows and blooms in May and June.

1. Draw one of the heads, showing the bracts of the involucre, the lingulate
or ray flowers and the tubular or disk flowers.

2. Under dissecting microscope draw a ray flower and a disk flower. Describe
each. What is the condition of the calyx? Why should the outer flowers develop
as ray flowers rather than the inner ones? Note that the ray flower is zygomor-
phic.

LXXXVI. Ledéntodon taraxacum L. Dandelion.

Order, Compositales. Family, Cichoriacee.

The dandelion blooms from early spring to late autumn, so plants may usually
be obtained without difficulty.

1. Sketch an entire plant, showing root, short stem, rosette of leaves, and
slender stems bearing heads of flowers. Note that the dandelion is geophilous.
Why does it not grow up out of the ground? How do you account for the rosette-
habit? Remember that the lowest seed plants were trees. This is: one of several
culmination types.

2. Make a sketch of a single head. Note that all the flowers are ligulate.
Also note that the embryonic corollas are tubular, showing five teeth on the limb,
and only become strap-shaped when they expand. Make a series of sketches show-
ing this. How does this indicate that Leontodon is a higher type of development
or specialization than Chrysanthemum leucanthemum?

LABORATORY OUTLINES FOR GENERAL BOTANY. 77.

3. Under dissecting microscope draw a single flower. Describe the pappus,
corolla, andrecium, and gynecium. :

4. Draw some of the ripe fruit. Note adaption for suspension in the. air.
Of what special advantage is this parachute arrangement? Note the action of
the involucre while the fruit is ripening. This extraordinary parachute is an ex-
ample of overadaptation.

5. How many seeds are in each dandelion fruit? i. e., how many for each
flower? How many seeds are produced on an average-sized head? About how
many heads of flowers are matured from a fair-sized dandelion plant in one
season? |

6. Suppose that you had but one mature dandelion plant and that it produced
seed normally for ten years and that each seed developed into a mature plant and —
began to reproduce at the average rate the second year, (1. e., when two years old)
how many offspring would there be at the end of ten years? Mature dandelion
plants multiply by division but this need not be taken into account.

7. The total land surface of the earth is about fifty-three millions oi square
miles, how many dandelion plants would there be for each square mile of land
surface at the end of ten years?

8. Nore. — The above problems will indicate to some extent the great possi-
bilities of reproduction present in many plants. It will be remembered that each
seed contains a little, dormant embryo; therefore, every seed that perishes means
the destruction of a young plant. It is evident that a very large per cent. of young
plants must perish each year, and that those which survive for any length of time
must usually undergo a severe struggle for existence. In this struggle for life and
place the fittest usually survive; 1. e., those which are able to grow more vigorously
and thus crowd out their weaker neighbors and those which are best adapted to
their environment.

OTHER “bY PES< OF ANGIOSPERMS:
LXXXVII. Triticum aestivum L. Wheat. (T. vulgare).

Phylum, Anthophyta. Class, Monocotyle. Order, Graminales. Family, Gram-
inacee.

Material should be collected during and after the flowering period in May and
June, and dried or preserved in 70 per cent. alcohol.

1. Study and sketch the spike (head) and describe. Note the character of the
stem. What mechanical advantage in the disposition of the tissues of the stem?
The axis of the spike is called the rachis.

2. Draw a single spikelet, noting the two empty glumes at the base, and
several flowers. How many flowers? What is the condition of the uppermost

flowers of the spikelet? The axis of the spikelet is called the rachilla.
. 3. Draw the two empty glumes noting their peculiarities.

4. Dissect a single flower. It is inclosed in two glumes, the flowering glumes;
the one with the awn is the lemma, and the inner one is the palet. Draw both and
describe. j

5. Just inside of the lemma at the base of the gynecium are minute scales
called lodicules. How many? Draw one under low power. What might they
represent? .

6. There are three stamens in the andrecium, and the gynecium develops into
a single grain. Make a diagram showing the positions of the empty glumes, the
lemma and palet, the lodicules, the stamens, the ovulary, and the axes of the
spike and spikelet.

78 LABORATORY OUTLINES FOR GENERAL BOTANY.

LXXXVIII. Phaséolus vulgaris L. Common Bean.

Phylum, Anthophyta. Class, Dicotyle. Order, Rosales. Family, Fabacez.

Fresh material can easily be grown in the greenhouse or garden, or use pre-
served and herbarium material. :

1. Study the entire plant, noting the trifoliate leaves, with sipules and
stipels. Draw.

2. Study the flower and note that it is bisporangiate, somewhat perigynous,
decidedly zygomorphic, pentacyclic, pentamerous except the gynecium which has a
single carpel, and that the stamens are diadelphous and keel of the corolla spirally
coiled.

3. Sketch a single bean pod. Of what importance is the bean family
(legumes) in general?

LXXXIX. Rosa virginiana L. Virginia Rose.

Class, Dicotyle. Order, Rosales. Family, Rosacee.

This is our commonest wild rose and blooms from May to July. Any other
wild species: will answer equally well. Preserved and pressed material will be
satisfactory if fresh material is not available. |

1. Note the general character of the flower —the very prominent hypanthium
or perigynous disk, the five sepals, five petals, numerous stamens, and numerous
free carpels.

2. Note that the flower is perigynous, bisporangiate, and an eS and
that only the calyx and corolla have definite numbers — pentamerous.

3. Compare a cultivated, double rose with the single one and note the origin
of the additional petals. The doubling is due to transformation of stamens into
petals —transformed organs.

4. General note. All flowers can be reduced structurally to. five types: a.
Hypogynous — Trillium, Catalpa; b. perigynous — Rosa, Prunus; c. perigynous
with adnate hypanthium— Malus, Crataegus; d. epigynous — Cypripedium, Cor-
nus; e€. epigynous with epigynous hypanthium— Fuchsia, Oenothera. Study and
compare five flowers representing the five different types.

XC. Fdachsia sp. Fuchsia.

Class, Dicotyle. Order, Myrtales. Family, Onagracee.

Fuschias are commonly cultivated in greenhouses and as house plants. The
flowers should be studied fresh and any of the common greenhouse species will do.

1. Study and draw the flower.

2. Draw the gynecium with style and stigmas. Cut cross sections of the
ovulary, noting the number of cavities and ovules.

3. Draw the perianth tube or hypanthium split open, showing the calyx,
corolla, and andrecium. How are these parts grown together? Note the color of
the calyx and the corolla.

4. Why does the epigynous condition and the peculiar development of the
hypanthium indicate a high type of floral development? Describe the entire
flower.

5. Make transverse and longitudinal diagrams of the flower, showing the
relationships of the parts.

XCI. Pdépulus deltoides Marsh. Cottonwood.

Phylum, Anthophyta. Class, Dicotyle. Order, Salicales. Family, Salicacez.

This is a large tree of rapid growth, common on flood-plains of rivers, and
is much planted for ornament. It blooms in April.

y

LABORATORY OUTLINES FOR GENERAL BOTANY. 79

1. Collect staminate and carpellate catkins or aments, noting that the trees
are diecious — some are staminate trees and some carpellate trees. Note the differ-
ence in color between the two kinds of flowers. How do you explain the differ-
ence? Draw the two catkins. .

2. Draw a single staminate flower and a carpellate flower and describe. Any
perianth? Why are the stamens red and not yellow as is commonly the case?
Why is it incorrect to say male tree instead of staminate tree and female tree
instead of carpellate tree? Or why should you not say male flower and female
flower ?

3. When the capsules ripen study the seed. How is it distributed? How
effective is this method? Why should only staminate trees be planted in a city?
How would you make sure that you had staminate trees to plant? Could you
plant cuttings? This tree endures city conditions quite well.

4. Note the different kinds of scars on the tree: leaf scars, stipular scars,
bundle-scars, self-pruning scars, lenticels. Note also that the pith is 5-angled. Is
there anything on the outside of the twig corresponding to this?

5. Note that the leaves have a strong tendency to take a vertical position
especially on twigs that grow erect. Draw and describe the flattened condition of
the petiole by which this is: accomplished. Why are the two sides of the leaf
nearly alike? What advantage in the vertical position? Why do you hear a
musical rustle of the leaves when the wind is blowing? Note the two glands at
the base of the blade. Of what use are the glands?

6. Study and draw self-pruned branches. Fresh material can be obtained in
summer and autumn and preserved in alcohol but the dry twigs will do fairly well.
Notice that the winter buds are in perfect condition. Draw the base showing the
surface of the scar. Draw a self-pruning scar that has healed over. How is the
cleavage plane or abscission layer produced in the basal joint? Why are the
branches pruned off? How old are the branches when self-pruned?

7. Note.— This outline may be used as a special exercise to be worked up
during the term. A special paper may be written on the subject including the
above and many other interesting points connected with the life of this tree.

XCII. Polemonium réptans L. Greek Valerian.

Class, Dicotyle. Order, Polemoniales. Family, Polemoniacez.

This is a perennial herb growing in woods. It blooms in April and May.
Fresh material must be used.

1. Describe the entire plant and sketch a branch showing the leaves and
flowers. If young plants are available, note the circinate venation.

2. Study a single flower. Note the blue color. Is blue a common color of
flowers? Note the character of the calyx, the corolla, the andrecium, and the
gynecium, and draw and describe each set.

8. Cut cross sections of the ovulary and draw. How many cavities? How
many ovules in each cavity?

4. If ripe capsules are present wet the seeds on the slide and examine care-
fully under low power. What peculiarity becomes evident after a few moments?
Crush or break up the seed with a scalpel and observe further. oy

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80 LABORATORY OUTLINES FOR GENERAL BOTANY.

SPECIAL EXERCISES ON ANGIOSPERMS.
XCIII. Comparison of Carpels.

i. If not previously studied, draw a carpel of Cycas revolita L.

2. Draw a carpel of the Kentnucky coffee-bean (Gymmnécladus didica (L.).)

3. Sketch a nearly mature fruit of the Velvetleaf (Abutilon abutilon (L.).)
Separate the ovularies and draw a single carpel.

4. Carefully separate the ovularies of the carpels of an orange (Citrus awran-
tuum L.) so they will lie side by side in a row. Draw. Note that some of the
divisions are smaller than the normal. There is a struggle for existence among
the members of the gynecium so that some are not fully developed.

5. Make a comparison of the four fruits studied above.

XCIV. Dicotyl Seed.

Study the fruit and seed of the Olive (Olea ewropaca L.). Use either fresh
or pickled olives. The samara of Fraxinus is also satisfactory. |

1. Sketch the entire drupe. Note that the pericarp consists of a fleshy exocarp
and a thick, stony endocarp. |

2. Break the endocarp and remove the fleshy seed within. Remove the mem-
branous seed coats and sketch the fleshy kernel inside. This is the endosperm.

3. Remove the embryo and draw, showing the short radicle, the two cotyle-
dons, and the plumule. Compare the kernel of Olea with that of the Pine seed
and note the differences.

XCV. Section of Leaf.

(a) 1. Cut cross sections of the lamina of a sunflower (Helidnthus annuus
L.) leaf fresh or preserved in alcohol, mount, and study under low and high
power.

2. Draw and describe, showing the following tissues: upper epidermis with
thick cuticle and multicellular hairs, palisade parenchyma, spongy parenchyma with
large intercellular spaces, sections of vascular bundles, and lower epidermis with
stomata and multicellular hairs.

3. How do you account for the palisade arrangement of the cells in the
upper part of the leaf?

(b) Cut sections of Beech Leaves or use prepared slides. Draw and com
pare the tissues with those in the sunflower leaf.

XCVI. Leaf Variation.

1. Obtain a series of fresh or pressed leaves of the red mulberry (Morus
rubra L.) or of the giant ragweed (Ambrosia trifida L.) and make outline sketches
of ten different forms. Note also the succession of leaf forms on a season’s
growth of Sassafras.

XCVII. Section of Winter Bud. ‘

1. From alcoholic material cut longitudinal sections of common lilac buds
(Syringa vulgaris L.) Mount and sketch under low power. Note the flat apex
with outer dermatogen and hypodermal meristematic tissue; anda little farther

LABORATORY OUTLINES FOR GENERAL BOTANY. QI

down the epidermis, cortex (periblem), procambium (formative tissue of vascular
bundles), and the central pith. .

2. Note the origin of the leaves, beginning at the apex, and also the origin
of the lateral buds in the axils of the leaves. Make a sketch showing the entire
upper part of the bud, with all the structures mentioned above.

XCVIII. Monocotyl Stem.

1. Cut cross sections of young corn stems preserved in alcohol, stain and
mount; or use prepared slides. Sketch the entire section under dissecting micro-
scope, showing epidermis, band of sclerenchyma, large pith or ground tissue, and
the scattered vascular bundles.

2. Under high power draw one of the bundles. Note the large vessels
situated in the xylem arranged like a letter V, the cavity in the tissue at the apex
of the V, the bundle of phloem between and beyond the two large vessels, and
the sheath of sclerenchyma about the bundle.

XCIX. Herbaceous Dicotyl Stem.
(a) Sunflower Stem.

1. Cut cross sections of a young sunflower stem preserved in alcohol, mount
and stain; or study prepared slides.

2. Sketch the entire section under dissecting microscope, showing cortex,
circle of vascular bundles, and large central pith. This vascular system is an
example of a siphonostele. Compare with Botrychium.

3. Under low power draw part of a section showing the epidermis with
epidermal hairs, the layer of collenchyma immediately below this, the parenchyma
_with resin passages, the vascular bundles with cambium layer, the medullary rays,
and the central pith.

4. Under high power draw a single vascular bundle, selecting one of the
narrow, oval type. Represent in order the external bundle of sclerenchyma, the
phloem, the cambium, and the xylem usually in a double layer.

5. Notice the mechanical principles involved in the structure of the stem and
the vascular bundle. Compare with a T railroad rail.

(b) Pumpkin Stem.

1. Cut cross and longitudinal sections of the stem of Cucurbita pépo L., stain
and mount, or study prepared slides. Sketch the cross section under dissecting
microscope. Note the epidermis, the cortex, the vascular bundles, the pith, and
the large central cavity.

2. Under high power study the longitudinal sections and draw sieve-tubes
showing the sieve-plates in the phloem.

3. In the xylem find and draw one of the large reticulate wood vessels; also
a spiral wood vessel with a single spiral thickening and one with two spirals; also
draw an annular wood vessel in which the thickenings are in the form of rings.

C. Dicotyl Woody Stem.

1. Cut cross sections of a very young twig of the beech (Fagus grandifolia
Ehrh.) and one a year old, preserved in alcohol, stain and mount, or use prepared
slides. Under low power note the cortical layer, the circle of vascular bundles
with medullary rays between, and the central pith. Draw. This is a siphonostele,

6

82 LABORATORY OUTLINES FOR GENERAL BOTANY.

Compare the younger section with the sunflower. Under high power draw a nar-
row sector passing thru a vascular bundle, showing epidermis, cork (periderm),
cork cambium (phellogen), secondary cortex (phelloderm), primary cortex,
sclerenchyma, phloem, stelar cambium, xylem (wood), and pith. Draw a single
complete bundle, showing the sclerenchyma, the phloem, the cambium and the
xylem. : é

2. Cut cross sections of twigs of the White Ash (Fréxinus americana L),
preserved in alcohol, one very young, one a few months old, one a year old and
one two years old. Study and draw the young sections noting the epidermis, cortex,
vascular bundles and pith. Study the one and two year old sections and note the
formation of the cork and the secondary development of phloem and xylem.
Draw and describe.

3. Cut cross sections of linden twigs (Tilia sp.) preserved in alcohol. Take
one very young branch, one a year old, one two years old, and one three years
old. Mount and stain; or use prepared slides. Study under low and under
high power. Draw the year old section, noting the following structures: epidermis,
cork layer, cortex, phloem and sclerenchyma layer (inner bark), stelar cambium,
xylem (wood) with medullary rays, and pith.

4. Make a series of diagrams showing the primary structure and how the
secondary structures are developed for the first three years. :

5. Under high power draw a small area of the xylem showing a medullary
ray, large empty pitted vessel, small empty wood fibers, narrow empty tracheids,
and protoplasmic wood parenchyma. Draw also a small area of cells from the
bark, showing a medullary ray, light-colored thin-walled sieve tubes, very thick-
walled bast fibers with only a minute lumen, protoplasmic companion cells in and
around the sieve tube tissue, and large protoplasmic bast parenchyma.

6. Cut cross sections of a very young and of-a year old twig of cottonwood
(Pépulus deltoides Marsh.); mount and stain. Note the following structures:
epidermis, periderm (cork layer) and the five corky ridges, phellogen (cork cam-
bium), phelloderm (secondary cortex), primary cortex, sclerenchyma (fiber bun-
dles), phloem with a narrow band of sclerenchyma, stelar cambium, xylem (wood),
and the five angled central pith.

7. Make a sketch of a cross section of a polished tree trunk of black walnut
(Juglans nigra L.), showing these structures: pith, heartwood (duramen), sap-
wood (alburnum), annual rings with early and late wood, medullary rays, the
stelar cambium and phloem (inner bark) separated by irregular strips or areas
or corky tissue from the outer bark. The outer bark has been developed from
the cortex and phloem and modified by successive layers of cork cambiums
(phellogen). These irregular strips of corky tissue can easily be seen in the
outer bark with the naked eye.

8. Compare with the walnut a polished section of the trunk of a bur oak
(Ouércus macrocarpa Mx.) In this the medullary rays are much more prominent.

9. Study cross section of the trunk of Catdlpa speciosa Warder. Measure
the width of the annual rings and draw a curve showing the growth in diameter
for the entire life of the tree trunk from which the section was taken.

Cl. The Root.
(a) Section of Buckeye Root.

1. Cut cross sections of one of the larger fleshy rootlets of Aésculus sp.
(preserved in alcohol). Mount and draw under low power, representing the fol-
lowing structures: the four or more primary xylem bundles, four or more primary

LABORATORY OUTLINES FOR GENERAL BOTANY. 83

phloem bundles alternating with the xylem, the beginning of the stelar cambium
passing between the xylem and phloem, the endodermis or bundle sheath, and the
broad cortex, with a superficial layer of cells known as the piliferous layer.

- 2. Cut cross sections of a somewhat older root which has turned brown,
mount, and sketch the entire section under low power. Represent the following
structures: the central strand of xylem composed of wood vessels and smaller
cells, the stelar cambium, the band of phloem consisting of several kinds of cells,
the remains of the endodermis, and the cortex and piliferous layer turned brown.

(b) Embryonic Root Tip.

1. Carefully remove the hard parts around the base of the embryo in a grain
of corn (Zéa mays L.) and with a razor cut longitudinal sections of the radicle
of the dormant embryo. The corn may be soaked in water for a while before
cutting the sections, tho this is not necessary.

2. Mount the central sections in water and sketch under low power. Note
the following embryonic tissues: the outer scutellum, the root-sheath of a dark
appearance inside of the scutellum, and the root tip inside of the root-sheath. The
root tip is made up of the root-cap (of a light color), the dermatogen (a layer of
' large cells inside of the cap), the dark layer of periblem, the central light plerome,
and the growing point at the tip of the plerome. Below the dermatogen, at the
apex of the root is the formative tissue of the root-cap, known as the calyp-
trogen. It will probably not be distinct enough in these sections to trace out, but
its position should be noted.

(c) Root Hairs.

1. Sprout grains of corn on moist blotting paper in a box or under a bell-
jar; after a few days the roots will be covered with root hairs. Sketch under
_ dissecting microscope.

2. With a scalpel cut off some of the epidermis containing root hairs, mount
and examine under high power. Draw and describe.

3. Under low power examine roots of young seedlings planted in soil and
note the relation of the root hairs to the soil particles.

CTF. | Lenticels.

1. Examine and sketch the bark of a green and of a year-old elder stem
Sambucus canadénsis L. showing the surface covered with lenticels.

2. Cut cross sections of the bark, mount, and examine under low power.
Sketch one of the lenticels. -How and where do they originate?

CIII. Starch, Cellulose, Lignin, tannin, etc.

1. Cut a potato and scrape off some of the cells. Mount in water and study
under high power. Draw some of the large starch grains present, showing the
hilum and the stratified structure.

2. Place a drop of iodin solution beside the cover-glass and watch its effect
on the starch. What is the color reaction?

3. Mount some wheat flower in water and treat with iodin. Note the blue
colored starch and the yellow colored proteid material.

4. Mount a hair of common cotton (Goss}pium herbaceum L.) It is made
up of nearly pure cellulose except the small central cavity in which is a small
amount of dry protoplasm. Draw. Treat with Schulze’s solution (Chlor-zinc-

84 LABORATORY OUTLINES FOR GENERAL BOTANY.

iodin) and after a while note the color reaction. Care must be taken so as not to
get any of this solution on the microscope as it is strongly acid.

5. Treat cross sections of a sunflower stem (from alcoholic material) with
Schulze’s solution, examine, and note the cellulose reaction in the walls of the
cortical and pith cells.

6. Treat a section of a sunflower stem with phloroglucin, mount and study
color reaction in the xylem bundle. Care must be taken in its use as it contains
an acid.

7. Cut cross sections of a young twig of linden preserved in alcohol, treat
with phloroglucin, mount, and note color reaction in the wood.

8. Cut cross and tangential sections of peach pits taken just when they are
beginning to harden. Mount and study the cells of this stony tissue. Draw a
number of the cells and describe. s

9. Tannin, which is the cause of astringency of many fruits, may be readily
demonstrated by Vinson’s method. Pour some sweet spirits of nitre, or a 20
per cent. alcoholic solution of nitrous ether, into a glass stoppered jar containing
broken pieces of pottery or glass to prevent the fruit to be treated from falling
into the liquid, and then drop in some fruit rich in tannin like green dates or
persimmons. Stopper tightly and let remain from 12-24 hours. At the end of
that period the tannin bearing cells will be of a dark brown color and will show
distinctly when the fruit is cut open. Mount some of the dark cells in water
and examine under low and high power. Note the large tannin masses. Crush
the masses by pressing on the cover-glass and note how they stretch and finally
break. A stained fruit may be preserved in 95 per cent. alcohol. Date fruits are
ideal for this experiment and may be obtained in autumn from Arizona.

10. Aleurone grains. Cut sections of the endosperm of a seed of Ricinus
communis L., castor-oil plant, after soaking in water. Mount in alcohol or
dilute glycerin and draw several cells showing the oval aleurone grains. Each
grain usually has a crystalloid and a globoid in its interior.

CIV. Crystals.

The material for sectioning may be preserved in alcohol.

1. Cut cross sections of the rhizome of the large blue-flag (/ris versicolor
L.) mount, and under high power draw the simple crystals present.

2. Cut sections of a year old twig of the wahoo (Eudnymus atropurpurcus
Jacq.), mount, and draw the large compound sphere-crystais in the pith and
cortex.

3. Cut sections of the rhizome of the lily-of-the-valley (Convallaria majalis
L.), mount, and draw the bundles of the needle-shaped crystals, raphides.

4. Cut cross sections of the leaves of the India-rubber fig. (Ficus eldstica
Roxb.), mount and draw the large cystoliths which are amorphous masses of
mineral substance suspended from a pedicel. The mineral substance of the cysto-
lith is mainly calcium carbonate. |

CV. Lipochrome. ‘ :

1. Cut thin sections of the rind of an orange, mount in water, and examine
under high power. Draw a cell showing the chromoplasts.

2. Cut sections of the root of the common cultivated carrot (Daticus carota

L.). Mount and draw a cell showing the color bodies.

3. Mount pieces of the yellow corolla of the squaw weed (Senécio aureus L.)
or any other yellow flower, examine under high power and draw a cell with
chromoplasts. Describe the cause of the yellow color in these tissues.

LABORATORY OUTLINES FOR GENERAL BOTANY. 85
CVI. Anthocyan.

1. Cut sections of the root of the red garden beet (Béta vulgaris L.), mount,
and examine under high power. Note that the red coloring matter is in the
cell sap.

_ 2. Cut sections of any leaf with red color as the red leaved coleus (Coleus
blimei Benth.), mount, and study the color under high power.

3. Cut off some of the epidermis of a red apple (Malus madlus (L.).) mount,
and study the cause of the color.

4. Mount part of a petal of a red greenhouse Pelargonium. Study the red
coloring matter in the cells.

5. Mount part of a petal of a blue flower like Sdlvia pitchert Torr. or Viola
odorata L.) and study the nature of the color.

CVII. Solution of Anthocyan.

1. Take a quantity of the corollas of Maurdndia barclaiana Lindl. (a com-
mon greenhouse vine) or flowers of Tradescantia virginica L., place them in a
dish and after crushing them cover with a quanty of 95 per cent. alcohol. After
a few days or so pour off the alcohol into a bottle and preserve.

2. Take a test-tube about one-third full of the alcohol and add a few drops
of aqua ammonia. Note color reaction. Neutralize with hydrochloric acid until
the liquid is again clear. Continue to add acid drop by drop. What is the color?

3. Place some red pelargonium (greenhouse geranium) flowers directly in
ammonia water. Note that they change to blue. Transfer to acid alcohol and
note that they change back to red.

4. How do you account for the change of color in many flowers during the
period of blooming and for the many varieties of color produced by cultivation as
in the common morning-glory (Ipomoéa purpirea (L)?)

CVIII. Temperature Test with Anthocyan.

1. Take two good thermometers which register alike, wrap the bulb of one
in a red begonia leaf and the other in a green begonia leaf, put each in a tumbler
and place for some time in direct sunlight. Note the difference in temperature.
Place the tumblers with thermometers in diffuse light and note the temperature
again. Place them in a dark box and after a while read the temperature. Make
a second test in the sunlight.

2. Describe one of the uses of anthocyan in roots, stems, leaves, flowers and
fruits.

CIX. Chlorophyll Solution.

1. Take a quantity of green leaves, such as the blue grass or greenhouse
pelargonium; place them in a porcelain mortar or other suitable dish; cover with
95 per cent. alcohol; and crush the leaves thoroly. After the alcohol is colored
a dark green filter into a bottle and keep in a dark place. |

2. Take a small quantity in a test-tube and examine by looking thru it
toward the window. Note the deep green color produced by the transmitted
light. Examine it by reflected light, by standing between the window and the
tube, and observe that the color of the solution appears a deep dull red, some-
thing like blood.

3. Take a small quantity of the solution in two test-tubes, and place one in
the sunlight and the other in a dark box. How long before the one in the sun-

86 LABORATORY OUTLINES FOR GENERAL BOTANY.

light fades out? Compare it with the one in darkness. Thus it will be seen that
sunlight when too intense will rapidly change the character of chlorophyll, altho
it is generally absolutely necessary for its development.

Cx Latex:

1. Take one of the large, red, deciduous stipules which cover the terminal
bud of Ficus eldstica at the time when it is becoming transparent, a few days
before it is ready to fall. Examine immediately by holding the stipule with the
inner side upon the stage of the microscope and examine with low and high power.
Note the complex system of lactiferous ducts and the movement of the latex in
them caused by its escape from the torn end of the stipule. At times the flow in
the ducts appears to be very rapid.

2. Mount some of the latex and examine under high power. Note the spher-
ical granules and draw. These are the rubber globules.

3. Why does the stipule become colored before it drops off from the bud?

CXI. Pollen-tubes in Artificial Cultures.

1. From an opening anther take fresh pollen of Canna, Hyacinth, or Begonia
and make cultures in the following solution:

a Cane: Suan sre Sie ue ee eee oe te eS
bit (Gelatin. Roca or ee oe eet oe es oe pains
C..SEap swatety iss ents ant on aul ge) aie

Heat the mixture over a water bath till the gelatin is dissolved.

2. To a cubic centimeter or two of this solution add an equal quantity of
tap water and filter into a small covered dish. Put the pollen into the solution and
also make hanging drop cultures, placing the slides into a moist chamber.

3. In 20 to 24 hours examine and draw several tubes representing successive
stages of development. Note the rotation of the cytoplasm.

4. Treat with iodin solution and note the position of the nuclei.

CXII. Karyokinesis.

Study the nuclear division in specially prepared slides of the root tips of
Allinm cépa L., the common onion. For a detailed study an oil immersion objective
and compensating oculars are necessary, but much may be learned with the ordinary
lenses. For staining use the fourth and fifth stains given in the appendix under
“paraffin imbedding.” The best time to kill the root tips is when they are about
an inch long. Kill at 11 P. M. or if this is not possible at 1 P. M.

1. Resting nucleus. Draw a cell some distance back of the tip where all the
nuclei are in the resting condition. Represent the cell wall, the cytoplasm with
vacuoles, and the nucleus. In the nucleus observe carefully the chromatin network
with chromatin granules and the nucleoli. The nucleus is enclosed in the nuclear
membrane. The lightly staining or hyaline substance in the uncleus, seen between
the meshes of the cromatin network is called achromatin.

9. Prophase. (a) In the first stage of division the chromatin network is
transformed into a continuous thread or spirem wound rather irregularly. At the
same time the incept of the achromatic spindle appears forming two dome-shaped
projections on opposite sides of the nucleus. This figure is known as the close
mother skein. Find a suitable figure, draw and describe.

LABORATORY OUTLINES FOR GENERAL BOTANY. 87

(b) Later the looped mother skew is formed by the shortening and _ thick-
ening of the continuous spirem which is thrown into a definite number of loops,
the heads of which in typical cases point toward the two poles of the spindle. The
nucleoli and nuclear membrane begin to disappear and the dome-shaped caps of
the spindle become more pointed. Draw and describe.

3. Metaphase. (a) After the nuclear membrane disappears the spirem breaks
into separate loops which are drawn into the equatorial plane with their heads
toward the centre. At the same time the spindle continues to elongate. This figure
is known as the broken mother skein. Draw and describe.

(b) When the chromosomes have come into the equatorial plane, there is a
pause resulting from the seeming pull of the spindle fibers in opposite directions
and the chromosomes are arranged in a very perfect star-shaped figure known as
the mother star. Each chromosome has in the meantime commenced to split lon-
gitudinally. This may be seen in ures more advanced mother stars. Draw and
describe.

4, Anaphase. (a) After longitudinal segmentation of the mother chromo-
somes has taken place, the daughter chromosomes are gradually pulled apart, the
separation beginning at the heads of the loops. This stage is called metakinesis.
In very favorable sections, centrospheres or small round. bodies may be seen at
the poles of the spindle, also polar radiations, but these can only be studied favor-
ably with an oil immersion lens. Draw and describe.

(b) After the chromosomes have been completely separated they arrange
themselves in star-shaped figures around the poles, while a central spindle of
threads appears between the two stars. This is the daughter star stage. Draw
and describe.

5. Telophase. (a) The chromosomes being oriented around the poles, now
begin to contract, becoming wavy in outline, and the free ends curve inward. The
threads of the central spindle begin to thicken preparatory to the formation of
the cell plate. Then the central spindle begins to bulge outward until it reaches
the cell wall. Nucleoli begin to appear. In favorable figures the polar radiations
are quite prominent and two centrospheres may be seen at the poles under a high
objective. This stage is called the loose daughter skein. Find a suitable figure,
draw, and describe.

(b) After the daughter cells are completely separated by the new cell wall
the threads of the central spindle and the radiations around the poles disappear,
and nuclear membranes appear around the daughter nuclei. The chromosomes
begin to be transformed again into an expanding chromatin network. This is
known as the close daughter skein. Select a suitable figure, draw and describe.

6. Make a series of diagrams showing the changes in the chromatin from one
resting stage to another.

CXIII.. The Reduction Division.

Study specially prepared slides of the ovularies of Lilium philadélphicum L.,
or the stamens of Liliwm tigrinum Andr. The best preparations can probably be
obtained from the stamens of Liliwm tenuifolium Fisch. Delafield’s haematoxylin
stain will bring out the cromatin well. The proper stages are obtained some time
before the flower opens. In the ovule of Lilium the archesporial cell is trans-
formed directly into the megasporocyte and this divides to form the first two cells
of the embryo-sac, no true megaspores being formed. During this karyokinesis the
chromosomes: are reduced and undergo a qualitative division.

88 * LABORATORY OUTLINES FOR GENERAL BOTANY.

Instead of Lilium the common Hyacinth may be used and will give excep-
tionally good slides for studying and counting the eight bivalent chromosomes.
Plant Hyacinth bulbs about October 22, in sawdust, and kill the flowers about |
November 1. The root-tips may be used for the vegetative karyokinesis. Stain in
Delafield’s hematoxylin. ? |

1. Under an oil immersion lens, study the early stages during which the chro-
matin network is being transformed into a spirem. Draw and describe.

2. Draw the stage when the spirem shows a single row of cromatin granules.

3. Study the stage in which the chromatin granules are dividing preparatory
to a longitudinal splitting of the linen thread. Draw.

4. Study the stage in which the spirem, after the chromatin granules have
divided, is twisting up into loops. There are twelve of these loops which will
break apart and form the twelve chromosomes; just half as many as in the
previous divisions during the life of the sporophyte. Draw carefully and make a
diagram representing a loop and the arrangement of the chromatin granules.

5. Draw a chromosome just after the loops have broken apart, showing the
twisted spirem and the closed head end of the loop. These are bivalent chromo-
somes made up of two univalents which are synaptic mates.

6. Draw a spindle in the mother star stage showing the fully developed
chromosomes. Make a diagram illustrating the structure of a chromosome.
Count the chromosomes in a favorable cell.

7. Study the metakinesis stage when the chromosomes have partly untwisted
and appear like elongated bands on the spindle, just before they break at the
center. Draw. Make a diagram showing how the chromosome is attached to the
spindle and how it divides.

8. Make a drawing of the early daughter star stage when the division of the
chromosomes is complete.

9. Make a series of diagrams showing the changes in the chromatin from
the early stage of division to the daughter skein stage. Compare the reduction
division with the vegetative division where longitudinal spitting of the chromo-
somes takes place.

CXIV. Fluctuating Variability.

One thousand soy beans (Soja max (L.) or other suitable seeds, all taken
from successive plants until the number is procured, may be weighed and assorted
into glass tubes, each tube containing the beans weighing within 25 milligrams of
each other. If small beans are used, a 10 milligram interval may be employed;
or if large beans are at hand, a 50 milligram interval in weighing will give satis-
factory results. The tubes may be placed in a box or frame and one or a few
sets, if properly managed, will be sufficient for the class. In small classes each
student may weigh a thousand beans, if suitable balances are at hand.

1. Count the beans in each tube and make a proper. tabulation of the number
for each weight.

2. Make a series of slender, contiguous rectangles with equal bases and by
shading show diagramatically the difference in number of the various weights
of beans. niet

3. Plot a frequency curve showing the fluctuations of the 1000 beans. Could
you state a principle relative to the abundance of the largest and smallest beans
as compared with those of intermediate weights? Look up Quetelet’s law.

EABORKATORY OUTLINES FOR GENERAL BOTANY. 89

CXV. Mendelian Principles of Heredity.

Take pure white and pure red dent corn or flint corn and cross pollinate them
—i. e. put pollen of red dent on the stigmas (silks) of white dent or the same
for the flint corn if desired. Keep the silks covered properly to prevent the access
of foreign pollen. Keep samples of the parent type of ears. Plant the hybrid
corn and pollinate the hybrid plants among themselves. The hybrid corn will all
have grains with red pericarps (sporophyte character). Plant the red grain and in
the next season there will be 4 white corn plants and # red corn plants. The white
if kept separate will remain white pure, but 4 of the red will give pure red and 4

of it will give red and white again in the proportion of 3:1. It will be seen,

therefore, that 4 was pure red, + pure white, and 4 hybrid red. The type ears

of the original parents and of the three succeeding generations are to be ar-
ranged and labeled in proper order in a glass case or glass jars and the student
is to note the striking hereditary results.

Also have corn showing first generation hybrid ears with purple and white
grains.

1. Note that in the first hybrid generation (Fi) the red color only appears.
The red is thus said to be dominant over the white.

2. Note that in the second hybrid generation (F,) pure white corn is again
produced from the red. The white character is said to be recessive to the red.
Note that there is no blending of the two characters red and white but that
the white is developed as pure from the red. Note the ratio between the red and
white. Let R stand for red and w for white and if in the Fs generation eggs
are produced having the R heredity and others having the w heredity and if the
same is true for the sperms, make a diagram showing all possible combinations
that could occur in fertilization of these two kinds of eggs and two kinds of
sperms. Using the letters R and w as symbols, arrange the combination on a
checkerboard of the proper number of squares.

3. Note the results in the third generation (F;), (a) that the whites pro-
duced only whites, (b) that 4 of the reds produced only reds, and (c) % of the
reds, i. e. 3 of the F, generation, produced both reds and whites again in the ratio
Cie nrayel es

4. Make a diagram with braces showing the inheritance from the original
pure parents to the third generation of offspring.

5. Note that these generations of corn illustrate the main facts of Mendel’s
laws of heredity—namely, (a) dominance and recessiveness, (b) the lack of
blending of certain hereditary factors or the characters resulting from their
activity during development, and (c) the segregation of the factors and char-
acters in definite ratios.

6. If white and purple endosperm characters are hybridized in corn could you
explain, by remembering the facts in relation to the female gametophyte of
the Anthophyta, and the endosperm (xeniophyte) why in the F, generation of ears
there could be both purple and white grains present on the same ear, while in the
case of the red and white corn the ears (both in the F; and F. generations) were
always either completely white or red? The purple-white hybrid will show
xenia as is also the case with the sweet-starchy hybrids mentioned below.

7. If a pure sweet corn ear is pollinated with pollen from both sweet corn
and field corn (starch corn) all the silks that receive starch corn pollen from
which fertilization results will show starchy endosperm in the grains, the starchy -
character being dominant. This immediate effect of the pollen is called xenia and

90 LABORATORY OUTLINES FOR GENERAL BOTANY.

is the result of triple fusion and dominance. Examine such ears. Under what
conditions could you tell that the ear had come from a pure stalk of sweet corn?

CXVI. Nature of Sex.

The following exercise will give the student some material in gaining a cor-
rect notion of the nature of the sexual state. Plant hemp (Cannabis sativa L.) at
any time from Dec. Ist to Jan. Ist in the greenhouse or window garden. It will be- .
gin to bloom in about three or four weeks. Hemp is diecious but the short light
period of winter causes reversal of sex in various parts of the plant, the staminate
plant developing carpellate structures and the carpellate plant staminate structures.
About 90% of the individuals will show reversal. If planted in May out of door
no reversal will take place in the ordinary varieties. :

1. Note the prominent sexual dimorphism in the blooming plants; also the
dimorphism of the floral envelopes of the staminate and carpellate flowers. Draw.

2. Find carpellate flowers or stigmas on staminate plants and staminate
flowers or stamens on carpellate plants,

3. Find abnormal structures and draw — stamens ending in stigmas, ovularies
with stamens growing from their walls, confused structures or sex mosaics, etc.

4. In your notes indicate how this experiment shows that the sexual state is
not dependent on the presence or absence of sex factors but is determined by the
conditions present at the time of development. Compare note 12, Outline XVIII.

APPENDIX.

GENERAL METHODS IN BOTANICAL MICROTECHNIQUE.

GENERAL METHOD WITH PARAFFIN IMBEDDING.

In the following account all details are carefully stated, so that a beginner
should be able, with little outside help, to carry the operations thru successfully.
The methods employed in preparing plant tissues must be considerably different
from those used in Zoology, since we usually have to deal with a thick cellulose
wall and very delicate protoplasm in which are usually contained large vacuoles
filled with cell sap, besides numerous plastids and food contents, all of which
tend to make it difficult to preserve and study the finer details of structure in plant
cells and tissues.

The object taken for a trial study may be some root tips of the common onion
(Allium cepa), or pieces of the young ovularies of some species of lily, as Lilium
longiflorum or L. philadelphicum. The root tips may be grown by placing an
onion in a flower pot with moist sawdust, and keeping it for a few days where
the roots will grow rapidly. The tips should be cut from one-half to three-
fourths of a centimeter in length, and killed at 11 P. M. or if this is not possible
at 1 P. M. The lily ovularies may be taken at various stages before and after
the flowers open, and cut into transverse pieces from one-fourth to three-fourths of
a centimeter long.

1.— KILLING AND FIXING.

The first thing to do in beginning to prepare any plant tissue for permanent
mounting is to kill and fix it in such a way that it will preserve the minute struc-
tures as near the living condition as possible. A sharp knife or scalpel should
always be used, and great care taken so as not to bruise or injure any of bo cells.

_ Killing Fluid.— The killing fluid is made up as follows:

1. Chromic Acid, Saas ae oe OS OS Erams
PomGl cial A Cent NCid 2.1 Se ee 0 CL
ee NILE ee eta at a ee ae 99.) Ke.

Have the killing fluid in a 4 oz. (120 cc.) bottle with a common cork. Sixty cubic
centimeters (2 oz.) of the fluid will be enough to kill one or two dozen objects
the size of the root tips. The material must be perfectly fresh and put into the
‘killing fluid as soon as cut. They will usually sink to the bottom after a short
time, especially if they are shaken a little from time to time. If much trouble is
experienced in having the objects float on the surface of the killing fluid, they may
first be immersed for a very brief moment in 95 per cent. alcohol, and immediately
after dropped into the killing fluid. This will cause them to sink; or force them
down with a plug of cotton. The objects must be kept in the killing fluid from
91

92 LABORATORY OUTLINES FOR GENERAL BOTANY.

twelve to twenty-four hours. The onion root tips should be left at least twelve
hours; for larger objects, a proportionately longer time. :

2.— WASHING.

After the tissues have been thoroly killed and fixed, the next thing neces-
sary is to wash out the acid. This may be done by pouring off the acid and filling
the bottle with water, and changing from time to time. They should be washed
in this way from one to four hours, depending on how often the water is changed.
A better way, however, is to set up and use the apparatus described as a con-
venient washing apparatus in this appendix. The water used for washing should
be rather pure. If this is not the case, distilled water had better be used.

3. — DEHYDRATING AND HARDENING.

The next step is to remove all water from the tissues, and this must be done
very gradually or the tissues will shrink and the protoplasmic contents of the cells
will be distorted so that the preparations will be worthless. Tc remove the water
successive grades of alcohol are used. During this process the objects may still
be kept in the same bottle. The amount of each grade of alcohol should be
sufficient to cover the objects well. The various grades of alcohol should be made
up and kept in a special set of bottles. It is best not to use the alcohol more than
once for this process. Carry them thru in the following order:

1 Oper cent Alcohol? 3cs7 sae es ey ak hours.
2-25 sper. cent; Alcohol,-4 2 3 <= 40S hous: :
3. 85> per cent: Alcohol) (<5. ee oe ee OO eniess
A 50. per cent-;Alcohol = Gx. 02 = 4 to “Schornse
baOeper cent) Aleoholi tae seer tO hours.

The objects should be hardened in the 70 per cent. alcohol at least two days,
and a longer period is generally better. They may be kept in 70 per cent. alcohol
for several months without injury.

6 *--85 percent Alcohol vcs i ee ak hours.
7. 95 percent; Alcohol, 3: <8) uo See 4 10 Ooms:
8. 100 per cent. Alcohol, 4 to 8 hours.

As a general rule, it is convenient to make three changes a day, morning, noon.
and night, except the 70 per cent

4, — CLEARING.

The objects must now be put into some fluid which will dissolve paraffin.
The best reagent for this purpose is chloroform. ;

1. Add one-third chloroform to the absolute alcohol. Let stand from four
to eight hours.

9. Add enough chloroform to make a two-thirds solution, and let it remain
from four to eight hours.

3. Transfer to pure chloroform and leave from six to twelve hours.

5. — IMBEDDING IN PARAFFIN.

The objects are now ready for the paraffin. This should be of good quality,
with the melting point at 49 degrees or 50 degrees C. The paraffin must be added
eradually, in the following manner: add small pieces of cold paraffin to the chlo-

LABORATORY OUTLINES FOR GENERAL BOTANY. 93

- roform in which the objects are, sufficient to form a cold saturated solution. After
the cold chloroform has taken up all the paraffin possible, say after about six or
eight hours, the objects must be gradually brought into the hot water oven. This
may be of various designs and sizes. A square oven with a side door is very con-
venient and cheap. The oven should be kept at a uniform temperature of about
52 degrees C. The bottle may first be placed on top of the oven, and then inside.
When warmed up to the temperature of the oven, melted paraffin, kept in a suit-
able dish in the oven, may be added from time to time, at intervals of two or three
hours. At the same time some of the mixture of chloroform and paraffin is poured
eff until the objects are in pure melted paraffin, with all traces of chloroform
removed. The objects should stay in the oven at least a day, and several days will
dco no harm if the temperature is uniform. It usually takes two days for the
operation. One day, however, is long enough unless the objects are very large and
difficult to penetrate.

MAKING THE CAKE.

The final imbedding can be easily done in the following manner: use a Petri
dish of proper size, 80, 120, or 150 mm. in diameter, depending on the amount of
material to be imbedded; or the paraffin imbedding dish described further on in
this appendix. Before imbedding, apply a very thin coat of a 50 per cent, aqueous
solution of glycerine to the parts of the dish with which the paraffin will come
in contact, and pour in a suitable amount of melted paraffin to make the cake.
The objects being in the bottle with the cork, turn the bottle upside down and
allow the objects to settle on the cork. Then remove the cork and let the paraffin
in the bottle, with the objects; fall into the dish. The objects may be arranged
in the paraffin with hot needles. Put the dish quickly into cold water, but do not
let the water flow into the dish until the paraffin is hard enough to bear the weight
of the water without being distorted. The paraffin cake must be cooled very
rapidly, and this is usually. done best in cold flowing water. After the cake is
thoroly hardened it is carefully removed from the dish and laid aside until used.
When the objects are once properly imbedded they can be preserved for an in-
definite period if kept in a cool place. The bottle in which the objects were kept
while passing thru the paraffin may be uséd for the same purpose for subsequent
imbeddings thus s:ving the trouble of cleaning out the paraffin each time. After
the objects are in pure chloroform they can be poured into this bottle, which will
have some paraffin adhering to its walls.

7.— CuTTING SECTIONS.

The sections must be cut on a mocrotome. ‘Cut one of the objects with a
suitable amount of paraffin out of the cake by means of a sharp scalpel, taking
care that the edges of the block will be parallel with the general contour of the
object. Trim the block down to a rectangular shape and fasten it to a block of
wood, or a special holder which goes with some microtomes. Before attempting
to fasten the block to the holder, have the top of this covered with a cushion of
paraffin. The paraffin block must be fastened firmly, and the edges especially
sealed with a hot needle so that there will be no danger of having it come off.
After having cooled off the block in cold water and trimmed the sides to be
parallel, fasten it into the clamp of the microtome and adjust the knife and clamp
so that the knife will strike the paraffin block perfectly parallel. The block should
be arranged with its long axis parallel to the knife edge. The ribbon of sections
should be straight and not coiled, If the ribbon coils, no good mounts can be

94 LABORATORY OUTLINES FOR GENERAL BOTANY, —

made even if everything else has been satisfactory so far. The desirable thickness —
of the sections depends somewhat on the nature of the material and the object to
be attained. As a general rule most sections may be cut ten microns (#) thick.
The-section knife or razor must be sharp and clean, with no trace of the smallest
notches, at least in that part with which the cutting is done. It is well to examine
the edge of the knife under the low power of the microscope to see that it is in
good condition. After the ribbon has been cut, care should be taken to have all
the pieces arranged in a continuous series, from left to right, on a clean sheet
of paper. The sections may be covered with a wide bell jar. If the sections do —
not hold together well while cutting, the paraffin may be too cold or there may be
other defects. These should be discovered and removed before proceeding further.
Ribbons should be cut yards in length, without a single break, when serial sec- —
tions are cut.
8. — MouNTING.

1. Take a clean slide and put a small drop of albumen fixative on it. Spread
it out over the surface with the finger into a very thin, even layer, being careful —
that no part of the finger touches the slide before being covered with a layer of —
the albumen. The layer must be quite thin so that you can.just leave a noticeable
impression of your finger on it. Too much albumen will ruin the preparation.
The albumen fixative is made as follows:

1. 25 cc. of the white of a fresh hen’s egg.
2: 15.cc. of glycerin:
3. 0.5 gram sodium salicylate.

Shake well and filter. This will keep well for a long time. ©

2. Now lay the slide down on the table and put a few drops of distilled
water on it, on top of the albumen film. Care must be taken here that the water
will not flow over the edge of the slide.

3. Cut the ribbon into suitable lengths, according to the size of the square
or oblong cover-glass, discarding the ends of the ribbon which do not contain
sections. With a scalpel lay the pieces of ribbon on the water in the center of
the slide in such a manner that one may begin at the upper left-hand corner and
follow the sections in lines, as one reads the words on this page. Allowance must
always be made for a certain amount of stretching of the ribbons when they are
heated, as they are always more or less ruffled. Never press the section down
with the finger or by any other means, else the fine structure will be broken and
distorted.

4. Warm the slide gently by putting it on the paraffin oven or holding them
over a flame until the heat has straightened out the sections on the water, but do
not let the sections get so hot as to melt the paraffin. The slides may now be
placed on wooden blocks, which may be kept constantly on top of the oven for
this purpose. It is best to let them remain for about twelve hours, when the
water will all be evaporated and the sections firmly dried to the slide. Four,
eight, or more slides can be carried thru at one time just as well as a single one.

9, — STAINING.

The sections are now ready for the staining. One must have the following
Stender dishes (60 mm. diameter x 90 mm. high) :

1. Filled with turpentine.
2. Filled with xylol,

LABORATORY OUTLINES FOR GENERAL BOTANY. Oy

Filled with absolute alcohol.

Filled with 95 per cent. alcohol.

Filled with 85 per cent. alcohol.

Filled with 70 per cent. alcohol.

Filled with 70 per cent. acid alcohol (1/10 cc. HCl to 100 cc.
alcohol).

8. Filled with 50 per cent. alcohol.

9. Filled with 25 per cent. alcohol.

10. Filled with distilled water.

Beek bars Aim oad

The various stains used may also be kept in Stender dishes if no special staining
_ dishes are at hand. The following stains are recommended for general purposes:

1. Anilin safranin, alcoholic (50 per cent.) solution, made by combining
equal parts of anilin water and a saturated alcoholic (95 per cent.) solution of
safranin. The anilin water is prepared by shaking up anilin oil in distilled water.
About 3.5 per cent. of anilin oil will be taken up by the water. es

A good anilin safranin may also be made as follows:

Make a 10 per cent. solution of anilin oil in 95 per cent. alcohol. When the
anilin oil is dissolved, add enough water to make the whole mixture 20 per cent.
alcohol (see paragraph on “Grades of Alcohol”). Add I gram of safranin to
each 100 cc. of this solution.

The safranin soluble in alcohol is the better one to use altho the safranin
soluble in water will also be satisfactory

2. Gentian violet, a 2 per cent. aqueous solution.
3. tron alum, a 2 per cent. aqueous solution of ammonia sulphate of iron.
4. Haematoxylin, a 0.5 per cent. solution obtained by dissolving in hot water.

5. Delafield’s Haematoxylin, to be obtained ready prepared from the dealers,
or prepared according to the directions given farther on.
The remaining Stender dishes will therefore be as follows:

11. Filled with anilin safranin.

12. Filled with gentian violet.

13. Filled with iron alum.

14. Filled with haematoxylin.

15. Filled with Delafield’s haematoxylin.

PREPARATION FOR STAINING BATH.

1. Melt the paraffin around the sections of two slides by heating them to
52 degrees C. in the paraffin oven.

2. Wash off the paraffin by putting the two slides back to back into the
Stender dish with the turpentine.

3. Transfer to Stender dish of xylol.

4. Next put them in succession into the dishes with absolute alcohol, 95 per
cent., 85 per cent., 70 per cent., and 50 per cent., or to whatever grade of alcohol
is present in the staining solution. If the stain is an aqueous solution pass down
thru 50 per cent. alcohol to 25 per cent. and then to water. Let them remain
in each one about ten seconds, more or less. Do not leave the dishes uncovered
longer than necessary. In passing the slide thru the solutions it is convenient
te take two at once placed back to back.

% LABORATORY OUTLINES FOR GENERAL BOTANY,

FIRST STAIN — ANILIN SAFRANIN.

1. Run the slides down thru the grades of alcohol to the 50 per cent.

2. Transfer the slides from the 50 per cent. alcohol to the anilin safranin
dish, and let them stain from two to twelve hours or longer. .

3. When the sections are stained wash them successively in the 50 per cent.
alcohol, 70 per cent., 85 per cent., 95 per cent. and absolute alcohol. Judgment
must be used as to how fast the transfer is to be made from one grade of alcohol
to the other. They must generally be taken quite rapidly, as the alcohol will take
out such stains as safranin.

4. Clear the sections by transferring them to the xylol. The sections must

be thoroly cleared. Leave them in xylol until they look transparent.

5. Take one slide out of the xylol at a time; wipe off the xylol with a clean
rag, wiping quite close to the sections, but do not touch the sections.

6. Put a drop or so of Canada balsam (dissolved in xylol) on the sections at
one side.

7. Put on a clean cover-glass in the followitye manner: holding the cover-
glass with the edges between thumb and forefinger, bring it down slowly and

obliquely upon the drop so that one edge of it is first wetted by the balsam; and

supporting the opposite edge with a needle, let the cover gradually settle down
and spread out the balsam. There should be no air bubbles and just enough

balsam to come to the edge of the cover-glass. Care must be taken to not let
the sections become dry at any stage of the foregoing process. The slides may

now be laid aside into a convenient place to dry. They may be studied imme-
diately if handled with care for a few weeks until the balsam has thoroly hard-
ened around the cover-glass. If balsam should get on the hands or instruments,
it can easily be removed with a little xylol.

SECOND STAIN —ANILIN SAFRANIN, GENTIAN VIOLET.

This makes a good double stain for many purposes. Stain first in the anilin
safranin from two to twelve hours; then wash in 25 per cent. alcohol; next in
water; and then stain from one to four minutes in the gentian violet. After
washing in water, pass thru the grades of alcohol, clear in xylol or clove oil, and
mount in balsam. :

THIRD STAIN — HEIDENHAIN’S IRON-ALUM-HAMATOXYLIN STAIN.

Run the slides down to water, and from this transfer to the iron-alum. Keep
the sections in this from two to four hours, and after washing well in tap water,
tain for twelve hours (or over night) in the hematoxylin. After this wash the
slides again in water and wipe them clean, and as close to the sections as is safe.
The sections are now black and must be cleared. To do this they are placed again
in the iron-alum, which gradually takes out the excess stain. They must be
closely watched and examined from time to time under the low power of the
microscope. When of a light greyish-blue- color they are washed again very thoroly
in tap water so that all iron salt is removed, and are then carried thru the grades
of alcohol, cleared in xylol, and mounted in balsam. If the iron-alum will not
remove enough of the stain use the acid alcohol after taking the slides thru to
the 70 per cent.

iS Ae ea yr
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PSA ee RCA SAGE Coe Ee One
Z Bol an + Axe ‘, ¥, faath: oN i as F ee
cere ee Pee eh Meat bee sts Cal SEM pe aa ee eee MY wits

LABORATORY OUTLINES FOR GENERAL BOTANY. 97

FOURTH STAIN — ANILIN, SAFRANIN, IRON-ALUM HAMATOXYLIN.

After one has become accustomed to use the foregoing combinations success-
fully, the following is well worth trying: Stain first in anilin safranin or in anilin
safranin and gentian violet, as described above; wash in water; and then stain
in the iron-alum-hematoxylin ‘according to the directions given, just as tho the
sections had not been stained at all. After staining, removing excess of stain,
and washing in tap water, pass thru the grades of alcohol, clear in xylol, and
mount in balsam. This is one of the clearest stains.

FIFTH STAIN — DELAFIELD’S H#MATOXYLIN.

In staining proceed as follows: Transfer to the stain from 25 per cent. alcohol;
stain one to four hours. Wash in tap water until the purple color develops. Pass
thru the alcohols to 70 per cent. Dip the slides rapidly into acid alcohol. Run
back to water and let remain until the purple color is restored. Pass thru the
alcohols, clear in xylol, and mount in balsam.

THE AGAR-AGAR METHOD OF IMBEDDING.

According to Bolton and Harris, “the method consists essentially in placing
the fresh tissues in a hot 2 per cent. solution of agar-agar to which 10 per cent.
of formalin has been added. The temperature of this fluid should be kept at
about 70° C. After remaining in the solution from one to several hours, the
tissues are removed and attached to blocks with a 5 per cent. solution of agar-
agar containing 10 per cent. of formalin. The heat and the formalin harden and
fix the’tissues at the same time the agar-agar impregnates it. After fixing th¢
tissues to blocks these are placed in 95 per cent: alcohol and allowed to remain
from two to four hours, and the tissues are then ready to be cut into sections
which can be stained, cleared, and mounted on slides in the usual way employed
for celloidin sections.”

The 2 per cent. solution of agar-agar can be made as follows: Take 1 gram
of agar-agar to 50 cc. of distilled water and boil for two hours. Then pour the
hot solution into a high cylinder and allow it to cool slowly until the cloud has
fallen. After the solution has cooled, cut off the clear upper portion and put it
in a glass jar. Place the jar in a basin of water and heat it until the agar-agar
is melted. Then add formalin in the proportion of 1 part of formalin to 9 parts
by volume of the melted agar-agar.

The 5 per cent. solution is made in the same way as the 2 per cent., only 1
gram of agar-agar to 20 cc. of distilled water are taken. Formalin should be
added in the same manner and proportion as in the 2 per cent. solution. The
) per cent. solution when melted is quite fluid, but when cold is more firm. It
becomes much firmer on the blocks after exposure to the action of strong alcohol.
Large quantities of the agar-agar solution can be prepared and preserved in air
tight vessels to prevent evaporation.

For fixing and imbedding only a small amount of the agar-agar solution need
to be taken. The solution should be kept at a temperature of 70° C. The fresh
tissues are first placed directly into the hot 2:per cent. solution and left for about
two hours and are then transferred to the 5 per cent. solution and left for one
hour or more, when they are ready to be imbedded. The tissues are imbedded
on wooden blocks. With a small camel’s hair brush put a layer of the hot agar-
agar on one end of the block, let it cool for a few seconds and then place one

Fi s

98 . LABORATORY OUTLINES FOR GENERAL BOTANY.

of the pieces of material on the block. Cover with more of the agar-agar solution
until properly imbedded. After fixing the tissue to the block, place in 95 per cent.
alcohol and let remain for twelve hours. The longer the agar-agar remains in the
alcohol the tougher it becomes. a 3
Instead of imbedding directly on the block the objects may be poured into a
suitable dish with a proper quantity of thick agar-agar and when sufficiently firm
the cake may be cut into suitable cubes. The cubes containing the objects are
kept until properly hardened in 95 per cent. alcohol when they pe be fastened
to the wooden blocks and sectioned.
Leaves or stems containing considerable silicon may be first placed for 12
or more hours in a 5 per cent. aqueous solution of hydrofluoric acid and after
washing in water imbedded as described above.
The material is sectioned on a sliding microtome in the same way as with Bye
celloidin method. The knife must be kept wet with 95 per cent. alcohol as well
as the blocks during the sectioning. The sections may be stained with safranin
and gentian violet, Delafield’s haematoxylin or other favorable stains.
This method is applicable where a histological study of the plant. tissue is
desired, but does not seem satisfactory for cytological work.

THE AGAR-AGAR AND PARAFFIN METHOD OF IMBEDDING.

It is often desirable to use the agar-agar method of imbedding and at’ the
same time preserve the sections in series. This can be accomplished very easily —
by a combination of the agar-agar and paraffin methods. Such objects as fresh
leaves and herbaceous stems and fresh or dried leaves with parasitic fungi are
favorable objects for trial. The tissues are killed and imbedded in the usual way
as described under the agar-agar method, the imbedding being done on a plate of
glass. After the agar-agar has cooled for a féw minutes the excess is trimmed off
and the object incased in the agar-agar block is placed directly into 70 per cent.
alcohol, passed up thru the grades of alcohol, and finally imbedded in paraffin in
the usual way. The sections will adhere to the slide without the use of albumen

fixative. CELLOIDIN IMBEDDING.

1. Make a solution of equal parts of ayeainte ether and absolute alcohol.

2. Make a 2 per cent. celloidin solution with the ether-alcohol mixture. Use
prepared celloidin like Schering’s Celloidin. Also make 4, 6, 8, 10, 12, 14, 16, 18,
and 20 per cent. solutions.

For the 2 per cent. solution take 2 grams of celloidin to 100 cc. of the ether-
alcohol mixture; for the 4 per cent. solution 4 grams to 100 cc., etc. Keep the
stock solution well corked.

1. Treat the fresh material to be imbedded in the same way as for paraffin
imbedding until it is in absolute alcohol. Leave in the alcohol long enough to —
insure complete dehydration.

2. Transfer the objects to the ether-alcohol solution and leave 12 to 24 hours,

3. \Next put them into the 2 per cent. celloidin solution for 2 or 3 days. i

4. Transfer the objects for 2 days to the 4 per cent. celloidin solution. 4

5. Put them successively for 1 day each into the 6, 8, 10, 12, 14, 16, 18, and
20 per cent. celloidin solutions.

6. Finally, if desired, a few dry chips of celloidin may be added from time to
time until the mixture is quite firm. The bottle with the objects may be kept on
2 paraffin oven at a temperature of about 40° C. if convenient.

7. The pieces of tissue may now be imbedded and the celloidin hardened in

one of three ways:

LABORATORY OUTLINES FOR GENERAL BOTANY. 99

A. Pour a sufficient quantity of the 20 per cent. celloidin solution into a
suitable flat dish; take the objects out of the bottle with a pair of forceps and
place them into this dish, arranging them with sufficient space between; cover
the dish, but not too tightly; and set aside for about 2 days, when by the evap-
oration of the ether and alcohol the celloidin will be hard enough to cut into

blocks. ec ete

Transfer the blocks for about 12 hours into chloroform and then put them into
‘a mixture of equal parts of glycerin and 95 per cent. alcohol, where they may be
kept indefinitely.

To fasten the celloidin blocks to the wooden blocks used for clamping to the
microtome, trim with a sharp scalpel, place the under side of the celloidin block
for a few moments in the either-alcohol solution, and then fasten it to the wooden
block which should have a cushion of thick celloidin solution. Let remain for a
little while to allow the celloidin to harden somewhat and then place into the
elycerin-alcohol solution until desired for cutting.

B. The pieces of tissue may be taken at once from the 20 per cent. celloidin
solution and imbedded on wooden blocks. Place a small quantity of the 20 per
cent. solution over one end of the wooden block, and arrange a piece of the tissue
on this cushion. In 3 or 4 minutes pour on a layer of the celloidin solution and
repeat this until the object is properly covered and imbedded. After about 5
minutes the block with the imbedded object is placed into chloroform and then
into the glycerin-alcohol mixture until desired for sectioning.

C. Take the objects out of the bottle with a coat of celloidin adhering and
place them for 12 hours in a bottle of chloroform. From this transfer to the
glycerin-alcohol mixture and leave for a few days or indefinitely. When ready to
section cover the end of a wooden block or object holder with thick celloidin
solution, and after trimming the proper end of the block of material and freeing
from glycerin, fasten to the moist surface of the object holder.

The sectioning must be done on a sliding microtome. While cutting sections
the knife and block should be continually wet with 70 per cent. alcohol or with a
higher grade up to 90 per cent. A camel’s hair brush is convenient for removing
the sections. The sections may be kept in alcohol of from 70 per cent. to 90 per
cent. In staining, keep the sections in a small Stender dish or other suitable
receptacle and treat in general similar to ordinary sections or paraffin sections
passing them up and down thru the grades of alcohol according to the stain
used. Jf desirable the celloidin may be removed, before or after staining, by
placing the sections for 15 minutes imto ether.

Woody tissues may be softened by the use of hydrofluoric acid. A 5-10 per
cent. aqueous solution of the commercial acid should be used. This may be kept
in a rubber bottle or in a glass bottle coated on the inside with a thick layer of
hard paraffin. |

After boiling the blocks of wood place them into the acid for 3 or 4 days, and
aiter washing them thoroly in water pass thru the grades of alcohol. MHard
tissues fixed in the ordinary killing fluids may also be softened by placing them
for some time into the hydrofluoric acid.

Various stains may be used, but Delafield’s hsematoxylin is a good general
stain for celloidin sections, and the following cleaning mixture will be found
especially suitable before mounting in Canada balsam:

MEME Penne, temic Veta teu oy Vis le chia es uerrO “parts:
Garbolte: -Acidec. ie hit 68h, ara ts parts,

£oeew
2

100 LABORATORY OUTLINES FOR GENERAL BOTANY.

COMBINATION OF THE PARAFFIN AND CELLOIDIN METHODS
OF IMBEDDING.

Infiltrate with celloidin in the usual manner, and Glen Ha the thick seleiate
place the object in a large quantity of pure chloroform either with or without
any quantity of the celloidin adhering to its outer surface. After leaving 24 hours
in the chloroform remove the objects to a bath of % chloroform and % cedar oil.
In 24 hours place in the oven in paraffin of the grade used for imbedding. Several
changes are necessary and more time must be allowed than for tissues imbedded
by the plain paraffin method. Paraffin will penetrate the celloidin itself and the
mass cuts with much less vertical compression than in the case of objects in
pure paraffin.

IMBEDDING SMALL OBJECTS.

Difficulty is sometimes experienced in imbedding small bodies to be sectioned
in large quantities, such as pollen grains, spores, unicellular alge, etc. The follow-
ing method will give good results:

The spores are placed in a homeopathic vial and treated in the ordinary way
for paraffin imbedding. The objects will sink to the bottorn and the different
reagents can be easily poured off. When the material is ready the bottle is filled
with paraffin and after the spores or other objects have settled to the bottom it is
quickly cooled off. When the paraffin is hardened the bottle is broken and Wore a
little trimming the block is ready for the microtome.

DELAFIELD’S HASMATOXYLIN STAIN.

To 100 cc. of a saturated solution of ammonia alum add, drop by drop, a
solution of 1 gram of hematoxylin dissolved in 6 cc. of absolute alcohol. Expose
to the air and light for 1 week; then filter. Add 25 cc. of glycerin and 25 cc. of
methyl alcohol. ‘Let the solution stand until the color-is rather dark. Filter and
keep in a tightly stoppered bottle. The solution should stand for 2 months before
it is ready for use.

SAFRANIN-GENTIAN VIOLET-ORANGE G. STAIN.

Safranin, according to the formula given” in the general method for paraffin
imbedding.

Gentian violet, a 2 per cent, aqueous solution; orange G., a 1 per cent. aqueous
solution. Stain 12 hours in the safranin; wash rapidly in 50 per cent. alconol,
25 per cent., and water. Stain 2 hours in the gentian violet. Finally stain 1 minute
in the orange G. Wash rapidly in 50 per cent. alcohol, 85 per cent., and absolute
alcohol. Clear in clove oil about 10 seconds. Replace with cedar oil. If not too
dark mount in balsam; if still too dark apply more clove oil.

ACID FUCHSIN STAIN.

Make a 1 per cent. aqueous solution. Stain 15 to 25 minutes, or much longer,
according to the material. This stain is good for free hand sections of alcoholic
material like the leaves of pine, etc. If sections have been overstained they may
be differentiated in a 1 per cent. solution of picric acid in 70 per cent. alcohol;
leave about 30 seconds and wash in 70 per cent. alcohol until the red color is
replaced, after which pass thru the grades as usual.

LABORATORY OUTLINES FOR GENERAL BOTANY. 101

A DIFFERENTIAL STAIN FOR CELL STRUCTURES.

Preparations stained in several colors are not always the best to show details
of structure. For ordinary class work, however, sections which bring out the
various cell organs in distinct colors are very convenient and to a large extent
preclude misinterpretations. The following will be found good for ordinary root
tips and the material must be killed in chrom-acetic acid:

Stain first two or three hours in anilin-safranin. ‘Next stain for about thirty
minutes in an aqueous solution of picro-nigrosin. The picro-nigrosin must be made
in the following proportions:

Distilled waterstig sue we oh ras Week fade LOO:
PeraC PACIOee chit hoamten uae, yr oben epee Letohirg sey:
Nigrosin, AF ORE PRE asa gine. Seat at Pa Qe ae PPR REM ED NEN IB oh ae

First dissolve the picric acid completely and then add the nigrosin. After
staining, dehydrate and mount in balsam. The stain is permanent, and if properly
done the results will be as follows: cell wall well stained and back; cytoplasm
of a bluish color; spindle threads bright green; chromatin network and chromo-
semes brick red; nucleoli bright red; thickened connecting fibers of the central,
barrel-shaped spindle dark green and prominent; granules of the cell plate black.

IODIN SOLUTION.

Make a strong solution of potassium iodide in distilled water; to this add
crystals of iodin until a saturated solution is obtained. This may be diluted
with distilled water until it is of a clear, reddish-brown color.

CHLOR-ZINC-IODIN (SCHULZE’S SOLUTION.)

1. Dissolve 110 grams of zinc in 300 cc. of pure hydrochloric acid and eyap-
orate to 150 cc.

2. Dissolve one gram of potassium iodide in as little water as possible and
add 0.15 grams of crystals of iodin.

3. Mix (1) and (2).

A good temporary stain for fresh or alcoholic material.

METHYL-GREEN STAIN.

Make a 2 per cent. aqueous solution of glacial acetic acid and add a little
methyl-green. This fixes and stains nuclei of fresh material fairly well. After
staining wash in 1 per cent acetic acid and mount in weak glycerin. The stain
fades rapidly.

BISMARK BROWN.

Make a 2 per cent. solution in 70 per cent. alcohol. This is good for cell
walls but not for protoplasm. Stain about 30 minutes.

PHLOROGLUCIN.

Dissolve phloroglucin in methyl alcohol (wood alcohol) until a saturated solu-
tion is obtained; then add gradually strong hydrochloric acid until precipitation
begins.

Use on fresh material or alcoholic material. Lignified walls assume a bright
red color. Sclerenchyma is also stained strongly by this solution.

=

ors
102 LABORATORY OUTLINES FOR GENERAL BOTANY.

é ~

EOSIN, ALCOHOLIC; SOLUTION,

Make a saturated solution in 70 per cent. alcohol. This is good for temporary y : : =
mounts of fungi. 7 Ae

EOSIN, AQUEOUS SOLUTION:

Make a saturated solution in pure water. This is good for temporary mounts
of fungi making evident transverse septa, etc. “

EOSIN, AQUEOUS SOLUTION.

It is generally desirable to have students do their own staining so far as time
will permit. Most good stains act too slowly to make this possible. An aqueous
1 per cent. solution of gentian violet or of fuchsin will give fair results on sections
of rhizomes, stems, roots, and wood. The sections can be stained all together in a
dish or one or more may be placed on a slide and covered with a drop of the
gentian violet. After staining from 1 to 4 minutes and dehydrating, mount in ea
Canada balsam and study immediately if necessary. A 1 per cent. aqueous solution — |
of equal parts of gentian violet and safranin is very good for some opjects.
The process in detail is as follows: Cut sections and place in 70 per cent.
alcohol; wash in water; stain; wash in water, in 70 per cent. alcohol, in 95 per
cent. alcohol, in absolute alcohol; clear in xylol; mount in balsam.

A RAPID STAIN FOR PARAFFIN SECTIONS.

One per cent. of fuchsin in 95 per cent. alcohol, stain for a few minutes and
wash again in 95 per cent. alcohol. This gives a fair stain to root tips witb

very little manipulation.
A GOOD STAIN FOR STARCH.

A very good and desirable stain for starch may be obtained by the use of
anilin-safranin and gentian-violet.

1. Anilin-safranin. Alcoholic fifty per cent. solution, prepared by combining
equal parts of anilin water and a saturated alcoholic ninety-five per cent. solution
of safranin.

2. Gentian-violet. A two per cent. aqueous solution. Stain from two to four
hours or more in the safranin and from two to eight minutes in the gentian-
violet. The slides should be taken thru the alcohols quite rapidly, or too much
of the stain will be washed out.

FARRANTS’ MOUNTING MEDIUM.
This medium modified as follows is good for various objects.

1. Gum arabic dissolved in cold water (enough

to “makevathick oan. csr eM de ok daa eve eae
De EGA COE Te i che rer i alteen 5) a Maar t y ceal ge i = ag oan ate
AWA Goi Cah cl Oe 6 r/con: eo MM AT AMR anh cer ome maie Maat a AIM yan ou Bis Ce
AY Alcohol (05: pericentye. 06 aay ah Wee aia A) (eee
Bas laeial acetic: ACid > ena Mel cLe ie taamuamee yah as hare tame tee

Care must be taken in adding the alcohol and acid to avoid coagulation.
Various fresh objects, as spores, small gametophytes, fungi, etc., can be mounted
in this medium directly from water or 95 per cent. alcohol.

LABORATORY OUTLINES FOR GENERAL BOTANY. 103

MOUNTING IN GLYCERIN.

e

The following method will be found satisfactory for making permanent glycerin
slides. The objects are taken from water to the pure glycerin with a little carbolic
~acid by adding the glycerin gradually and permitting the water to evaporate until
absolutely pure glycerin alone is left. The objects are then placed in a small drop
of glycerin jelly on the slide and a ring of Canada balsam is placed around the
drop, after which the whole is covered with a square or round cover-glass. The
glycerin adhering to the objects may be drained off by placing them on a clean
piece of blotting paper before transferring them to the drop of glycerin jelly. The
glycerin jelly and balsam will not mix, and if the two mounting fluids have spread
out properly the slide should be perfectly sealed. Such slides need not be sealed in
any other way. If the glycerin jelly is too thick warm a drop on the slide over the
alcohol lamp.

This method is suitable for various alge, molds, powdery mildews, hairs,
scales and many other objects.

TO MOUNT FOSSIL OR DRY DIATOMS.

Place the diatoms or other like objects in 95 per cent. alcohol. Put a drop
of the alcohol, with diatoms, on the slide; dry over a flame; cover with xylol;
and when clear, mount in balsam.

TO MOUNT SPORES AND OTHER DRY OBJECTS.

To mount spores of fungi, ferns, lycopods, etc., also myxocycetes, apply a layer
cf albumen fixative, sprinkle the spores on this, dehydrate with absolute alcohol,
clear with xylol, and mount in balsam.

PERMANENT MOUNTS OF POLLEN.

When only external characters are desired very good mounts can be made in
the following manner: Put a drop of albumen fixative on the slide and spread
ii out in a thin layer, sprinkle the fresh pollen on this, then put the slide into a
Stender dish of absolute alcohol to which equal parts of a small amount of safranin
and gentian violet have been added. About 0.1 gram to each 100 cc. of alcohol
is the proper amount. After 5-20 minutes transfer to absolute alcohol, clear in
xylol, and mount in Canada balsam.

TO PRESERVE A TEMPORARY MOUNT FOR A FEW DAYS.

Place beside the cover glass a drop of 50 per cent. glycerin, letting the drop
just touch the water of the mount, when it will be drawn in gradually as the
water evaporates. This will of course kill any living organisms.

TO PREPARE: DRY WOOD, FOR CUTTING.
Boil blocks of a suitable size in water and place in 70 per cent. alcohol. Cut
on a hand microtome when desired.
TO PREPARE VARIOUS OBJECTS FOR FREE HAND SECTIONING.

Roots, rhizomes, herbaceous stems, pine leaves, and other herbaceous parts
are simply placed in 70 per cent. alcohol and preserved until desired for study.

104 LABORATORY OUTLINES FOR GENERAL BOTANY, ©

TO PRESERVE FREE HAND SECTIONS.

Sections of wood, stems, roots, etc., may be preserved indefinitely in 70 per
cent. alcohol. If stained they may be kept in xylol for several days and mounted

at any time. They should be kept in the dark and carefully corked or stoppered, ,

otherwise they may fad and the xylol evaporate.

DROP ‘CULTURES.

Take a ring of glass made especially for the purpose or build up a chamber
on the slide with paraffin. Put a drop of distilled or boiled water in the bottom

of the chamber. Apply vaselin to the edge of the ring for sealing. Put a drop
of water or other culture medium with spores on the center of the slide and piace
gently on the ring with the drop hanging down.

KILLING FLUIDS.

(a) FLEMMING’S WEAKER FLUID.

I\“per -cent..chromic acids 7%! [orgies Pies te oars
1. per ‘cent:. glacial acetic acid, o's a Bea Oe ee
Waters ni pe er ke OO bee Rane Py 2 ket 0) 2 eee
1 Percent:OSMIC: ACld: 7) ok ee et: eee nat a eee

Add the osmic solution from time to time as the reagent is needed for
use, since it does not keep well. This fluid is expensive on account of the osmic
acid.

The blackening due to the osmic acid may be removed by placing the slides
in turpentine exposed to sunlight when they will stain well with a number of
reagents. The best stain, however, is the safranin, gentian violet, orange G.
combination.

(b) WEAKER CHROM-ACETIC ACID SOLUTION.

Glactal acetic acide beh eae eee Cees
Chromic acids ip ied ils ees ee ee) lee Aes eee Ia
Wake iat ice cide Ae AERC OL TAY cy cee tore gel ei Ct tens Aaa es

This is good for alge, root tips, and other delicate material. It causes little
or no plasmolysis. It is improved by adding for each 10 cc. (as it is used) one
drop of a l per cent solution of osmic acid. —

(c) ACETIC POTASSIUM-BICHROMATE FLUID.

Glacial iacetic: acts is yy eee et Re ere) eres
Potassium’ bichromatey 2 ei ek 2 tie eee Oe ena
Waters) ce each Se Cedi Us Daemon ea ee

CLEARING MIXTURES AFTER LOW GRADES OF ALCOHOL.

Use phenol, or equal parts of phenol and bergamot oil, phenol will clear after
low grades of alcohol, even water. The sections can then be transferred immedi-
ately to balsam.

CELLOIDIN FIXATIVE.

5 per cent. solution of celloidin, . . . . . I part.
Clove “oily ji” caer secs rerum fie: cite! gold pala a REDE

LABORATORY OUTLINES FOR GENERAL BOTANY. 105

PERENYITS FLUID.

Wattic sacid’ ClO per cent))solutiony cer 2) 7 4 parts.
Alcoltol: (95. per cent:),, 2: .5%. Kyi Sc eae parts:
Chromic acid (% per cent. aqueous solution), . 3 parts.

This is good for preparing shell perforating alge and other lime incrusted
forms.

If too slow in action a few drops of nitric acid may be added to the amount
used, about 2 drops to 10 cc. of the fluid.

SCHULTZE’S MACERATING FLUID.

This mixture is used to macerate woody tissues.

POLASSIUIEACMORALE Wc? GI es is Oe pass rei? wen eb Oar:
INERICS ACI ee ar aey eee ON OUTS. de Le REE OB) ee

The chips or fragments of tissue are boiled in the fluid for a short time in
a test tube. When the material is sufficiently macerated, pour off the fluid, wash
well in water and after teasing the specimens apart with needles preserve and
mount in glycerin.

The boiling should be done out of doors or under a hood as the acid vapors
are very corrosive and injure microscopes and other metallic apparatus.

COPPER SALT SOLUTION.
‘CCamphor, 20 grams dissolved in 50 cc. of 95% alcohol.

Glacialavere-agide i rg ik OC) oe AOD ee:

Woprer acetate. ar a at hee Gal et oO (erams,
Gdppet, caroride CCusy $6 swe se ce ene ee, oO. Srans:
pbpistiWead. water cc. 2 frome a one ei Bao 4) Peters

A larger or smaller quantity may be made in the same proportions. This
solution is valuable for preserving green alge, liverworts and other green plants.

GRADES: OF ALCOHOL.

General pharmaceutical rule for making any lower grade or percentage of
alcohol from any given grade or percentage.

Take of the grade at hand as many volumes as the number of the per cent.
you wish to make; then add to this enough volumes of pure water to make the
total number of volumes agree with the number of the per cent at hand.

For example, suppose you have 95 per cent. alcohol at hand and wish to make
76 per cent. alcohol, take 70 cc. of the 95 per cent. alcohol and add to this 25 cc.
of pure water. This will give you 95 cc. of 70 per cent. alcohol.

MARKING SLIDES.

Various methods have been described for labeling slides while they are being
stained. Very good results may be obtained by the following method:

The medium used is watergiass, an aqueous solution of sodium- or potassium-
silicate. It should be thinned if necessary till it will flow well from a pen.
An ordinary steel pen of the stub or ball-pointed sort is used. After the slides
are marked they must be heated, either before or after they dry, preferably by
holding them for a few seconds in the blue cone of a bunsen flame till the
waterglass decomposes giving off strong jets of sodium light, and at the same

=

106 LABORATORY OUTLINES FOR GENERAL BOTANY. , |

@

time effervescing so as to leave behind a rough sandy surface. This is then 2
rubbed down by a single stroke against the edge of the table or any hard object —

and leaves a ground glass surface which, if the fixing has been properly done, is

permanent and will not be affected by any reagent which does not attack the

slide itself. If desired some such dye as carmine may be stirred into the solution
tc make the marks more conspicuous.
Slides may also be marked with hydrofluoric acid as follows:

Take a clean slide, dip one end into paraffin, and let it cool. With a needle ; aes
scratch whatever mark or number is desired on the paraffined surface, and then

apply a drop of hydrofluoric acid to the mark by means of a wooden toothpick.

Let this remain 2-5 minutes; then melt the paraffin and clean the slide. Any pes
number of slides may be marked in a series in this way. Ordinary precautions -

must be taken in handling the hydrofluoric acid.

A CONVENIENT WASHING APPARATUS.

The apparatus described below will be found convenient for washing material
after being killed in an acid or other solution. It consists of a glass or other
tube of suitable thickness, ten centimeters
long and from two to three centimeters in

screw; a funnel of brass or tin about five
centimeters wide at the top, four centimeters
deep, and ending below in an open tube one
centimeter long; and two cotton or linen

together as shown in the figure, and may be
supported on a tripod. (Fig. 18.)

When the objects are ready to be washed,
remove the ring and cloth and pour the
objects, with the solution in which they are
contained, into the tube, and then replace the
ring and cloth, and let water flow into the
funnel. Usually it will be found best to let
the lower part drip into a glass dish. When

transferred to a bottle by taking off the cloth
into which they will have settled. In this way
small and delicate objects can be handled
without injury.

=a

or for collecting small water plants and ani-
mals. For instance, by having a cloth with a coarser mesh above and a finer
one below, organisms of a certain size can be collected in the lower cloth free
from foreign matter or larger animals and plants.

THE PARAFFIN IMBEDDING DISH.

When imbedding in paraffin a suitable dish must be used. When only a few
cbjects are to be imbedded a small paper tray may be made. Petri dishes of
suitable size may be employed for larger quantities. A dish especially made for
this purpose will, however, be found most convenient. (Fig. 19.)

diameter; an open brass ring with thumb-

cloths for strainers. The apparatus is put —

the objects are washed they can easily be

Pres. is ie ace This apparatus can also be used as a filter, ©

Ru
ae
ou
Part
era
ie
"
Bey
ae
»
J*
,

LABORATORY OUTLINES FOR GENERAL BOTANY. 107

The bottom is a square plate of glass of proper size and thickness, while the
box consists of an open brass ring with a thumbscrew. The sides of the ring
* should be smooth, and should be of sufficient thickness to secure rigidity. It
will be found convenient to have rings of several sizes, —50, 80, 120, and 150 mm.
im diameter. Before using apply a very thin. coat of 50 per cent. glycerin to the
glass. and ring, and place the dish on an ordinary plate so that cold water can
be run under it.

THE LABORATORY NOTE BOOK.

A good note book is essential to good work in the laboratory, and tho one
finds note books of about all shapes, sizes, and qualities,.there are few which are
really satisfactory for laboratory work. The note book should be 7x10 inches
in size. This size is not too large to be easily handled, and is still large enough
to hold most of the drawings made by the general student. It should be made
up of two kinds of paper and two paper covers of stiff cardboard, strengthened
with cloth on the back edges; all perforated exactly, with three holes (the outer
holes being two inches from the ends), and tied together loosely with a shoe-
string. The paper should be unruled, and of good quality, so that the notes can
be taken in ink; the drawing paper should also be such that a good hard pencil
or India ink can be used for drawing. A third kind of paper can be used for
- the finer work.

This note book will lie absolutely flat on the table and there are no trouble-
some clamps in the way. It can be folded back to back, can be increased indefi-
nitely in-size, and the work can be rearranged in any way desired. Such note
books can be made by any local dealer at small expense, and the paper sold to the
students in any quantity and quality desired.

Substantial cloth covered backs with rings are now available for permanent
binding, and if properly made are in some respects more convenient than books
tied with strings.

MI'CROSCOPE COVERS.
A very convenient and serviceable microscope cover can be made from heavy

Manilla paper rolled up and glued together in the shape of a slender cone of
proper size. A better one can be made in the same way with transparent celluloid.

GLOSSARY.

All important terms and phrases used have been defined and the derivation,
when other than Anglo-Saxon, indicated. It was thought advisable to use the

Latin alphabet in Greek words since very many college students have no acquaint-

ance with the Greek,

Ab-nor’mal (organ) [Gr. anédmalos] —An organ or part which deviates from the
usual type in some extraordinary way, as in shape, size, color, or other
character.

A-bor’tive (organ) [L. abortivus] —An organ or part normal in the species but

which has failed to reach full development in the individual.

Ach-ro-mat’ic spindle [Gr. achrématos] — The spindle shaped figure of Heo
formed in the cell during nuclear division. The spindle is usually not
stained readily by stains which color the chromatin intensely.

A-chro’ma-tin [Gr. Acroma] — The substance of the nucleus which is ‘not readily

colored with basic stains. :
Ac’ti-no-mor’phic [Gr. Riesinds Signorphep Radel. symmetrical; a flower or
organ which can be cut. into similar equal halves by two or more:planes.
A-cu'mi-nate [L. acuminatus] — Tapering gradually to the apex.
/E-cid’i-um — A cluster-cup, developed in one eee of the life history of certain
rust amet Same as Aecium.
7E’-ci-o-spore’ [Gr. Aikia-+ spdros] —In rusts, one of the nonsexual spores pro-
duced in chainlike rows in the Aecium.

7E’-ci-um [Gr. Aikia] — The type of sorus which is developed in the first parasitic —

spore-bearing stage of a rust fungus. A cluster-cup.

7&-tha’li-um [Gr. aithalos] —A compound sporebearing mass, farmed in certain
slime-molds, by the fusion of many sporangia.

Al-bur’num [L. albus] — The young, usually light-colored, soft wood of a tree
next the cambium layer; the sap-wood.

A-leu’rone grains [Gr. aleuron] — Proteid material occurring in the form of
minute granules in the seeds of numerous plants.

Al'ga [L.] —A thallophyte with chlorophyll.

Alternation of generations— A condition existing in the life cycle of plants in
which a sexual generation alternates with a nonsexual one.

A’ment [L. Amentum]—A slender usually flexible spike of flowers, as in the
willows. g

An’a-phase [Gr. ana-+phasis] —The stage in karyokinesis during which the
daughter chromosomes separate and pass to the poles of the spindle.

A-moe’boid [Gr. amoibé] — Like an amoeba, aaron ak in its movements or changes
of shape.

A-nal’o-gous [Gr. ana-+ logos] —Organs or parts similar in function but not in
origin and structure.

A-nas’to-mos’ing [Gr. anastomosis] — Connecting so as to form a network.

A-nat’ro-pous [Gr. ana -+ trépos] — An inverted ovule with the micropyle near the
hilum, the funiculus being united with the body of the ovule.

(108)

x
a

LABORATORY OUTLINES FOR GENERAL BOTANY. 109

An-dre’ci-um [Gr. andros + oikos] — The whole set of stamens in a flower.

An'dro-spo-ran’gi-um [Gr. andros + sporos + aggeion] — A spore case containing
androspores.

An’dro-spore [Gr. andrés-+ sporos] —A small spore in certain algae which gives
rise to dwarf male individuals.

An’e-moph’i-lous [Gr. a‘nemos — philos] — Pollination by the agency of the wind.

An’gi-o-sperm [Gr. aggeion + spérma] — A seed plant which has the seeds pores
in the carpel, the enclosing case being called an ovulary.

An’i-so-car pic [Gr. anisos — karpos.] — Having the carpels of the gynecium fewer
in number than the parts in the other floral sets.

An’nu-al [L. annualis] — Yearly; living but one year.

Annual ring — The layer of wood produced each year from the cambium layer in
dicotyl and other similar plants.

An’nu-lar wood vessel [L. annulus]— A wood vessel having thickenings in the
form of rings.

An’nu-lus [L. annulus] —In the agarics a ring of tissue surrounding the stalk; in
ferns, the ring of cells partly or completely surrounding the sporangium. A
specialized ring of vesicular cells between the oN of the sporangium and
the operculum of a moss.

An’‘ther [Gr. antherds] — The spore-bearing part of a stamen; the part which
finally contains the pollen sacs.

An’ther-id’i-o-phore [Gr. antherdés + idion + phords] — An organ or branch which
bears the antheridia.

An'ther-id’i-um [Gr. antherds-+idion] —A male organ of reproduction; a
spermary.
An-tho-cy’an [Gr. anthos + kuanos] —a coloring matter in plants of various shades

of blue, red, etc.

An-tip’o-dal cells [Gr. anti-+ pots] — The cells, usually three in number, at the base
of the female gametophyte in angiosperms.

Ap‘ic-al cell — The cell in the tip of some bryophyte and pteridophyte stems by the
division of which the growth in length takes place.

| Ap’o- the’ci-um [Gr. apo + théke] — An open cup-like or disk-like body cone

asci, in fungi and lichens.

Ar’che-go’ni-al chamber [Gr. archégonos] —A small depression at the tip of the
female gametophyte in the seeds of cycads, into which the necks of the
archegonia open.

Ar’che-go’ni-um [Gr. archégonos] —A female organ of reproduction; a. special
kind of ovary.

Ar’che-go’ni-o-phore [Gr. Archégonos + phérein] — The branch or structure which
bears the archegonia.

Ar’che-spo’ri-al cell [Gr. Arché-+ spdros] — The cell from which sporocytes are
finally developed.

Ar’che-spo ri-um — The cell or group of cells which give rise to sporocytes.

A-re’o-la [L. areola] —A small space as between cracks, grooves, or ridges on
various thalli. |

Ar il— An exterior covering or fleshy organ around the hilum of a seed.

As’co-carp [Gr. askos + karpos] — A fruiting body containing asci with ascospores.

As‘co-spore [Gr. askos + spores] —A spore produced in an ascus.

As’cus [Gr. askés] — A sac-like body in which spores are produced, usually definite
in number.

As-sim’i-la’‘tion [L. assimilatio] —In plants, the process by which dead, organic
food materials are changed into the living protoplasm.

Za

110 LABORATORY OUTLINES FOR GENERAL BOTANY.

At’a-vism [L. atavus] — A reversion to an ancestral type.

At’a-vis'tic organ — One which shows in the individual a return to some ancestral
type. by

At'ro-phied organ [Gr. atrophia] — An organ or part normal in the individual but
which has become reduced thru pathological conditions, or thru disuse.

Ax‘il— The point of a stem just above the base of the leaf.

Awn—A slender bristle-like organ. .

Bac-te’ri-um [Gr. baktérion] — Any of the organisms belonging to the order Bac-
teriales or even of the Schizomycetae.

Ba-sid’i-o-spore’ [Gr. basis + sporos] —A spore borne on a basidium.

Ba-sid'i-um [Gr. basis] — A special form of sporophore characteristic of the Basid-
iomycetae and related plants, typically bearing four basidiospores.

Bast — The phloem of the vascular bundle, the inner bark.

Bast fiber — Sclerenchymatous tissue in the bark of various plants. ; a
Bast pa-ren’chy-ma [Gr. parégchuma] — The soft thin-walled cellular tissue in the

phloem. |
Bi-en’ni-al [L. biennalis] — Lasting for two seasons or two years. | ae
Bi-lat’er-al [L. bi-+ lateralis] — Having a similarity of parts on the right and left | . %

side, or on the two sides of a dividing plane. .
Bi-ol’o-gy [Gr. bios + logos] — The science of living organisms, including anne
and animals.
Bi-spo-ran’gi-ate [Gr. bi-+ sporos + aggeion] — Having both microsporangia and
megasporangia; having both stamens and carpels. |
Biv’a-lent chromosomes [L. bis + valens] — Chromosomes formed during the reduc- —
tion division by the synapsis of two simple or univalent chromosomes.
Bordered pits (of gymnosperms) — peculiar pits in the walls of the tracheids.
Bot’a-ny [Gr. botane] — The science which treats of plants.
Bract — A small, rudimentary, or imperfectly developed leaf.
Brood bud—A vegetative reproductive bud or structure.
Broken mother skein — A figure in nuclear division after the spirem has broken up
into distinct chromosomes.
Brownian movement [Pertaining to Robert Brown] — The peculiar, =v ibeatoee move-
ment exhibited by microscopic particles when observed in water or other
fluids under the microscope.

Bud — A small structure on the end or the sides of a stem, which may develop into
flowers or leafy shoots.

Budding — In plants like the yeast, the process by which new celle: are developed
by the gradual formation of a protuberance from the mother cell.

Bundle scar— A scar in a leaf scar produced by a vascular bundle.

Bundle sheat (of vascular bundle) —A definite layer of cells completely or par-
tially surrounding a vascular bundle.

Ca-lyp’tra [Gr. kaluptra] — The hood or cap covering the sporangium (of a moss)
and representing the enlargéd archegonium.

Ca-lyp’tro-gen [Gr. kaluptra + gignomai] — The layer of cells at the Hp of a root
from which the rootcap originates.

Ca’lyx [Gr. kalux] — The outer set of sterile floral leaves; the whole set of sepals.

Cam’‘bi-um [L. cambire] — The cylinder of growing cells in some stems.

Cam’py-lot’ro-pous [Gr. kamptlos + tropé] — An ovule curved like a horseshoe.

Cap‘il-li’tium [L. capillus] — The mass of threads in the sporangium of a slime-
mold or puffball.

_Car’po-stome ['Gr. karpos + stoma] — The opening in the tip of a cystocarp.

LABORATORY OUTLINES FOR GENERAL BOTANY. 111

Cap’sule (of flowering plant) [L. capsula] —A dry fruit of two or more carpels,

usually dehiscent by valves or teeth; sometimes applied to the sporangium
of a bryophyte.

Car’pel [Gr. karpos] — The megasporophyll of a seed plant; the modified leaf or
stem bearing the ovules.

Car’pel- Bi ee only carpels or carpellate flowers.

Car-po-go’ni-um [Gr. karpdos + gignesthai] — Sometimes applied to the oogonium
of the red algae.

Car’po-spore [Gr. karpos + sporos| —A kind of spore produced in the ecystocarps
or sporocarps of the red algae. ‘

Cat’kin [Cat+-kin] —The same as ament; a slender usually flexible spike of
flowers as in the willows; (so called from its resemblance to a cat’s tail).

Cell [L. cella] — The unit of plant and animal structure, usually consisting of a
small mass of protoplasm, containing a nucleus and with a cell wall.

Cell plate — The central disk or wall formed in the central spindle between the two
daughter nuclei in cell division, which finally divides the cell into two
daughter cells.

Cel‘lu-lose — The carbohydrate which constitutes the essential part of the ees:
cell wall of plants.

Cen’o-cyte [Gr. koinéds +kutos] —A mass of cells or protoplasts with a common
limiting wall but without walls separating the individual cells, the several or
numerous nuclei apparently imbedded indiscriminately in the cytoplasm.

Cen’o-cyt’ic — Having the nature or structure of a cenocyte.

Cen'tral spin’dle— The spindle of threads developed between the two sets of
daughter chromosomes in nuclear division.

Cen‘tral strand (of mosses) —A strand of narrow, elongated cells in the center of
a moss stem.

Cen’tro-some [Gr. kéntron + s6ma] — A minute body appearing beside the nucleus
or at the poles of the spindle during cell division.

Cen’'tro-spere— Same as centrosome, but including the attraction-sphere around
the central granule.

Cha-la’zal [Gr. chalaza] — Perainine to the base of an ovule.

Chlam’yd-o-sporé [Gr. chlamus + sporos] — A thick-walled, nonsexual spore as in
the smuts.

Chlo’ro-phyll [Gr. chlords + phullon|] — The green coloring matter of plants.

Chlo‘ro-plast [Gr. chlords + plastos] —A minute green, chlorophyll-bearing color
body in the cells of ordinary plants.

Chro’ma-tin granules [Gr. chro6matos] — The granules in the chromatin which stain

- prominently with various dyes.

Chro’ma-tin network — The network of threads with granules in the nucleus.

Chro'ma-to-phore [Gr. chroma - phérein] —A splastid containing some coloring
matter. ~

Chro’mo-plast [Gr. chroma + plastds] — A plastid containing some color other than
green.

Chro’mo-some ['Gr. chroma +soma]— One of the group of bodies formed from
the chromatin network during karyokinesis. The chromosomes are con-
sidered to be the special bearers of hereditary factors.

Cilt-a [L. cilium] — Slender protoplasmic lashes or projections, having the power
of movement, extending from certain cells.

Cir’ci-nate [L. circinatus] — Rolled inward from the apex.

o

112 LABORATORY OUTLINES FOR GENERAL BOTANY.

Class (of plants) —A group of plants in one of the seven subkingdoms or sub-
series having an evident relationship to each other.

Cla’vate [L. clava] — Club-shaped.

Cleav’age plane —A separation layer produced in leaves, stems, and other organs.
by means of which they are separated from the plant.’

Cheis’to-the’ci-um [Gr. kleisto6s + théke] — An ascocarp in which the asci are com-
pletely enclosed, the body having no ostiole.

Close daughter skein — A figure produced by the chromatin during karyokinesis, in
which the chromosome loops are more or less joined by connecting strands.

Close mother skein — An early stage in karyokinesis when a continuous spirem is
present which has not yet folded into definite loops nor broken apart.

Col-len’chy-ma [Gr. Kolla-+ égchuma]—A tissue of plant cells which have the
walls thickened at the angles.

Col’o-ny [L. colonia] —A group of unspecialized unicellular plants loosely con-
nected in the vegetative pnase.

Col’u-mel’la [L. columella] — A column-like axis in a sporangium.

Companion cells (in the bast) — Protoplasmic cells in and around the sieve tube
tissue of the phloem.

Com’ pound leaf —A leaf composed of several divisions or leaflets, the blades of
which are not continuous. :

Con-cen'tric vascular bundle [L. con-+centrum]—A vascular bundle with the
xylem in the center surrounded by phloem, as in certain ferns.

Con-cep’ta-cle [L. conceptaculum]— A cavity, in a fruiting body, opening to the
outside by an ostiole and containing either spermaries or ovaries, or both,
as in the brown alge.

Cone — A strobilus, a primitive flower as the carpellate cone of the pine.

Co-nid'i-o-phoré [Gr. kénis + phoéros] —A branch or organ which bears conidia.

Co-nid’i-um [Gr. konis] —A nonsexual spore formed by the cutting off and
specialization of cells from the tip of a conidiophore, or by division of
fungal hyphe. ‘

Con’ju-ga’tion [L. conjugatio] — Specifically the union of similar gametes, but
generally the union of egg and sperm in fertilization or the union of any
two bodies as univalent siapibosames into bivalent ones.

Con-tract’ile vac’u-ole [L. contractus vacuus] — A pulsating cavity in the interior
of a protozoan supposed to be excretory in function.

Cork — The suberized tissue produced in the outer bark by the cork cambium or
phellogen.

Cork cambium — The tissue of dividing cells in the bark which produces the cork
cells.

Co-rol'la [L. corolla] — The inner set of sterile, usually colored, floral leaves; the
whole set of petals.

Cor'tex [L. cortex] — The parenchymatous tissue in a young stem between the
epidermis and the phloem.

Cor’ti-cal — [L. cortex] — Pertaining to or consisting of the cortex.

Cos'ta [L. costa] — The midrib of a moss scale.

Cot'y-le’don [Gr. kotuledo’n] — A leaf-like organ or the embryo in the seed.

Cross or transverse section — A section cut at right angles to the long axis of an
organ as the stem.

Crys’tal-loid (in aleurone grain [Gr. krustallos] —A minute crystal-like particle
present in some aleurone grains, ;

LABORATORY OUTLINES FOR GENERAL BOTANY. 113

Cu’ti-cle [L. cuticula] — The outermost tissue of cells, usually one layer thick, in
the higher multicellular plants. The cuticle is often destroyed at an early
stage as in dicotyl woody stems.

Cyclic [Gr. kuklos] — Having the floral organs arranged in cycles or whorls.

Cys’to-carp [Gr. kustis + karpés] — A form of sporocarp produced in the red alge,
having the carpospores surrounded by a thickened envelope.

Cys’to-lith [Gr. kustis + lithos] —A concretion of calcium carbonate deposited in
certain plant cells, usually on a projection from the cell wall.

Cy-tol’o-gy [Gr. kutos + logos] — The branch of biology which deals with the struc-
ture, functions, and activities of the cell and its various protoplasmic organs.

Cy’to-plasm ['Gr. kutos + plasma] — The more fluid part of the protoplasm ex-
clusive of the nucleus and plastids.

Daughter cell— A cell which has been derived from the division of a mother cell.

Daughter stars— The karyokinetic figure in the anaphase when the daughter
chromosomes are approaching the poles.

De-cid’u-ous [L. deciduus] — Falling away at the end of the growing period by a
separation layer or cleavage-plane.

De-fin’i-tive nucleus (cell) [L. definitivus] — The nucleus which is formed in the
female gametophyte of the anthophyta by the conjugation of the polar cells
(usually two) and which give rise to the endosperm, frequently after having
conjugated with a sperm nucleus.

Der-mat’o-gen [Gr. dérma-—+ gignomai] — The embryonic tissue from which the
epidermis is produced. Incipient epidermis.

Di-chot’o-mous [Gr. dichotomos] — Once or several times two-forked.

Di-cot’yl [Gr. di+kotule] — A plant belonging to the class of Dicotyle, or having
two cotyledons.

Di-e’cious [Gr. di+ oikos] —Having the microsporangiate or staminate flowers

and the megasporangiate or carpellate flowers on separate plants.
Dip-loid [Gr. diploos) — Having a double number (2x) of chromosomes.

Disk flower — One of the tubular flowers in such inflorescences as are present in

the sunflowers and related plants.

Dis-sem’i-na’tion [L. disseminatio] — The act of scattering seed.

Dom’i-nant character [L. dominans] —A character possessed by one of the parents
of a hybrid, which appears in the hybrid and prevents the corresponding re-
cessive character from the other parent from developing so long as their
factors are associated.

Dor’sal [L. dorsualis] — Pertaining to the back.

Dor’si-ven’tral [L. dorsum -—+venter] —Having a distinctly differentiated upper
and lower surface or part, usually lying flat on the substratum.

Drupe [Gr. druppa] —A simple, usually indehiscent fruit with fleshy exocarp and
bony endocarp.

Du-ra’men [L. durare] — The heart wood of a tree or shrub.

Dwarf branch—A highly specialized and reduced shoot bearing leaves, as in the
pine and larch.

Dwarf male—A very small male plant produced in some alge like CGidogonium.

Early wood — The first, often porous, wood of the annual ring produced by the

-cambium in the spring. Sometimes called spring wood.

E-col’o-gy [Gr. oikos + logos] — The study of all the relations of plants associated
and grouped together under definite conditions of life, or of the individyal
and its structures as related to or influenced by the environment,

Egg— The female reproductive cell or gamete,

8 :

114 LABORATORY OUTLINES FOR GENERAL res

Egg-apparatus — The two synergids and the egg or oosphere present in the tip of
the angiosperm female gametophyte.

F-la’ter [L. elatus] — An organ in the sporangium for Sp enmen the wall and aiding
in scattering the spores.

E-mar’gi-nate [L. emarginare] — With a notched apex.

Em’bry-o [Gr. émbruon] —An incipient plant. In the seed plants the term is
usually restricted to the young sporophyte in the seed. After SPrOune it is
a seedling or juvenile individual.

Em’bry-o-sac (sack) [L. saccus, Gr. sakkos] — The female gametophyte, contained
in the ovlue of seed plants.

Em-bry-on’ic — Pertaining to an embryo.

Emp’ty glume — One of the two glumes at the base of a grass spikelet.

En’do-carp [Gr. éndon +karpos] — The inner layer of the pericarp.

En-do-der'mis [Gr. éndon + dérma]— A limiting layer of cells inside of the corti-
cal tissue, often separating the parenchymatous from the vascular tssue; in
many monocotyls dividing the stem into a central and outer portion.

En-do-phyt’ic [Gr. éndon + phuton] — Applied to a plant growing within another
plant on which it may or may not be parasitic.

En’do-sperm [Gr. éndon-+ spérma] — The nutritive tissue developed around the
embryo in the female gametophyte of angiosperms. It is developed from
the definitive nucleus and typically has the triploid (3x) number of chro-
mosomes.

En-to-moph’i-lous |[Gr. éntomon + philos] — Said of plants in which pollination is
accomplished by the agency of insects.

En-vi'ron-ment — The external condition and influences surrounding the living
organism. The influence may be inside of the organism or even inside of
the cell.

Ep’i-der’mis [Gr. epi-++ dérma] — The external layer of. cells in plants.

E-pig’y-nous [Gr. epi guné] — Having the calyx, corolla and andrecium above
the ovulary. . 3 .

FE-qua-to’ri-al plane [L. equator] — The central plane of the cell, cutting the cell at ii
right angles to the direction of the nuclear division.

Eu-spo-ran’gi-ate [Gr. eu + sporos + aggeion|] — Having the essential part of the
sporangium produced from the sub-epidermal cells.

Ey-a-nes’cent [L. evanescens] — Disappearing early.

Ey-o-lu’tion (organic) [L. evolutio] —The process by which the members of the
organic kingdom have developed thru descent from each other. Evolution in
general tends from the undifferentiated to the specialized; from the simple
to the complex ;-from the low to the high; but the tendency may also be in
the opposite direction, resulting in. a simplification of the complex or a de- .
generation of the functional parts.

Ex’o-carp [Gr. éxo + karpés] — The outer layer of the pericarp.

Eye’spot — A small body containing pigment usually of a reddish color, present in
many unicellular plants and animals and especially in zoospores. It is sup-
posed to be sensitive to light.

Fam’i-ly (of plants) [L. familia] —A group of related plants, comprising one or
more genera and ranking below the order.

Fe’male — Any plant which produces directly (either following a reduction division
or not) eggs or female gametes.

Fe’male gam’ete |Gr. gameté] — The egg cell or oosphere.

Fern — Any plant belonging to the class Filices.

LABORATORY OUTLINES FOR GENERAL BOTANY. PADS)

Fer’tile [L. fertilis] — Applied to a plant or part which produces normal spores,
pollen, seeds, eggs, or sperms. .

Fer’ti-li-za’tion [L. fertilis] —In botany, the union of the two gametes; the con-
jugation of the egg and sperm.

Fil’a-ment [L. filum] — A thread-like plant body as in the alge and fungi; in the
flowering plants, the slender stalk of the stamen below the anther.

Fla-gel’‘lum [L. Flagellum] — A long whip-like protoplasmic mobile process, pro-
jecting from certain cells, especially zoospores and spermatozoids.

Flo’ral organ [L. floralis] — The organs of a flower, mainly sepals, petals, stamens,
and carpels.

Flow’er [L. flos] —The modified spore-bearing shoot or branch of the antho-
phyta; the various types of strobili or cones of the Calamophyta, Lepido-
phyta, Cycadophyta and Strobilophyta are primitive flowers to which the
term may be applied in a general way.

Flow’er-ing glumes [L. flos, gluma] — The two chaffy bracts enclosing the grass
flower.

Fluc-tu-a’tion [L. fluctuatio] —A variation due to the direct effect of the environ-
ment during the life time of the individual. :

Fo-li-a’ceous [L. foliaceus] — Belonging to a leaf; leaf-like.

Foliage leaf — A normal green leaf.

Foot (of sporophyte) — The basal part of the sporophyte of a liverwort or moss;
the absorbing organ of a pteridophyte embryo.

Frond [L. frons] — A large or highly developed thallus or gametophyte: Sometimes
wrongly applied to fern leaves.

Fruit [L. fructus] — The spore-bearing parts of seedless plants; but especially in
the seed plants the ripe carpels or ovulary with the seeds and whatever
parts are modified or consolidated with these organs.

Fun’gus [L. fungus] — Any thallophyte without chlorophyll.

Fu-nic’u-lus [L. funiculus| — The little stalk by which the ovlue or seed is attached
to the placenta.

Gam’e-tan’gi-um [Gr. Gameté or gamétes + aggeion] — An organ which produces
gametes.

Gam’ete [Gr. gamein] — A sexual cell; an egg, sperm, or isogamete.

Ga-me’to-phore [Gr. gameté or gamétes + phérein] — A branch which bears sexual
organs. .

Ga-me’to-phyte [Gr. gameté or gamétes + phuton|— The sexual generation of
plants.

Gem’ma [L. gemma] — A brood-bud capable of reproducing the plant.

Gen’er-a-tive cell [L. generatus] — Sometimes applied to the sperm mother cell in
the pollengrain of Anthophyta. This cell by division, either in the pollen-
grain or in the pollentube, ae rise to two sperms.

Ge’nus [L. genus, 'Gr. génos] —A group of plants of lower rank than the family.
The generic name constitutes the first of the two words in the binomial name
of a species.

Ge-oph’i-lous [Gr. gé aie Farth-loving; growing under the ground, as
under-ground stems.

Ge-ot’ro-pism [Gr. gé + trépein] — The tendency of roots or other plant organs to
assume growth curvatures under the influence of gravity.

Ger’mi-na’tion [L. germinatus] — The division or budding of a spore or reproduc-
tive cell; the beginning of the growth of a new individual plant.

116 | LABORATORY OUTLINES FOR GENERAL BOTANY.

Gills [of toadstools] — The spore-bearing plates or lamellae on the pileus of one
of the Agaricacee.

Gir’dle view — The side of a diatom where the two valves overlap.

Glo’boid [L. globus] — A small globular body often found in aleurone grains.

Glume [L. gluma] — The scaly bracts of the flowers and spikelets of grasses and
sedges. |

Grain [L. granum]— Any minute particle; the seed-like fruit of plants belong
to the grass family.

Ground tissue— The general pith-like tissue in a stem thru which the vascular
bundles and sclerenchyma bundles pass as in the fern stem.

Guard cells — The bordering cells on either side of a stoma.

Gym’no-sperm [Gr. gumnos + spérma] —A plant having naked seeds; a plant be-
longing to the subkingdom Gymnosperme.

_Gy-ne’ci-um [Gr. guné + dikos] — The whole set of carpels in a flower.

Hab’i-tat [L. habitare] — The place where a plant grows.

Haem’‘a-to-chromé [Gr. haima-+ chroma] — A red coloring matter in some alge as
in Sphaerella.

Hap-loid [Gr. haploos] — Having the single or Se sates (X) a chromo-
somes.

Haus-to’ri-um [L. Lariat —JIn parasitic plants, a specialized outgrowth from the
stem or mycelium serving as an organ of absorption. :

Heart’ wood — The hard, central part of a woody stem, usually differing in color
from the younger outer sapwood. It is called duramen.

He’li-ot-ro-pism [Gr. hélios + trépein] — Same as phototropism.

He’lot-ism [Gr. hélios] — The condition of symbiosis in which one of the sym-
bionts, altho obtaining food from the other and giving none in return, causes
no special injury as in the relation between alga and fungus in a lichen.

Her-ba’ceous [L. herbaceus] — Leaf-like in texture and color; having the charac-
teristics of an herb.

Her-ba’ri-um [L. herba] — A collection of dried specimens of plants systematically
arranged.

He-red’i-ta-ry [L. hereditarius] — Capable of descending or of being transmitted ©

from parent to offspring.

Hereditary character — Any structure or peculiarity developed in an individual as
the result of the normal activity of one or more hereditary factors.

Hereditary factor — The property or ability possessed by a cell thru the activity of
which an hereditary character is developed, either independently by its own
activity or in connection with other properties or factors.

He-red’i-ty [L. hereditas] —The biological principle or law in accordance with
which an organism transmits its qualities and characteristics to its offspring.
The ability of an organism to transmit its peculiarities to its offspring

Her-maph’ro-dite [Gr. hermaphrdditos] —An individual having both male and
female sex organs.

Het-er-é-cism [Gr. héteros + oikia] — The condition in which a parasite passes thru
different stages of its life history on an alternation of hosts.

Het’er-o-cyst [Gr. héteros + kustis] —A large special type of cell occurring in the
filaments of certain blue-green alge. ) .

Het-er-os’por-ous [Gr, héteros + sporos] — Having two kinds of spores; having
megaspores and microspores.

His-to-log’ic-al [Gr. histos + logos] — Pertaining to the cellular structure of the
tissues.

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LABORATORY OUTLINES FOR GENERAL BOTANY. 117

Hold’fast — A disk-like or branching body by means of which certain algz are
attached to the substratum or support.

Ho’lo-phyte [Gr. holos + phuton] —A plant which produces all of its food from
inorganic substances.

- Ho-mol’o-gous organs [Gr. homdlogos] — Organs or parts similar in origin and

structure.

Ho-mos’por-ous [Gr. homds + sporos] — Having only one kind of spores on the
sporophyte generation.

Hor’mo-gone [Gr. hormos + goneia] —A chain of cits in certain alge separated
from the parent body and by which the plant is propagated.

Host [L. hostis] — The plant or animal on which a parasite lives.

Hy’a-line [Gr. hualinos] — Clear and translucent.

Hy’brid [L. hybrida] — The offspring of two parents which differ in one or more
hereditary factors or characters, especially the offspring of parents from
different races, varieties or species.

Hy’dro-phyte [Gr. hudor + phuton] —A water plant, or one growing in very wet
conditions.

Hy’gro-scop’ic [Gr. hugrdés + skopéin] — Readily absorbing and giving off water,
by which movements are produced.

Hy-me’ni-um [Gr. humén] — The spore-bearing surface of certain fungi.

Hy-pan’thi-um [Gr. hupd-+ anthos] — Any enlargement or special development of
the torus, in a flower, on which the sepals, petals, and stamens are borne; a
perigynous disk.

Hy’pha [Gr. huphé] — A branch or part of a filament of a fungus mycelium.

Hy’po-cot’yl [Gr. hupo + kotule] — That portion of the stem below the cotyledons
in the embryo of a seed plant.

Hyp’o-der’mal [Gr. hupo + dérma] — Pertaining to the tissue or parts beneath the
epidermis.

Hy-pog’y-nous [Gr. hupd-+ guné] — Having the calyx, corolla, and andrecium

below the gynecium.

Hy-poph’y-sis [Gr. hupo + phusis] — The expansion or part just below the sporan-
gium of a moss, often with stomata.

Hy-po-thal’lus [Gr. hupo + thallos] —A fleshy or membranous base bearing spor-
angia.

In’cept, in-cip’i-ent [L. incipere] — An organ or part in its first stages of develop-
ment in the individual, or in its embryonic condition.

In-du’si-um [L. indusium] — The membranous covering of the sori in. many species
of ferns. :

In-flo-res’cence [L. inflorescens] — The flower cluster of a plant and its mode of
arrangement. .

In-her’it-ance [L. inhereditare] — The act or state of transmitting hereditary fac-
tors from one generation to another. The set of hereditary factors possessed
by an organism which is or may be transmitted.

In- -i'tial cell [L. initialis] — The original cell from which a tissue is developed.

In’ner bark — The tissue between the stelar cambinum and the cork cambium.

In-teg’u-ment (of ovule). [L. integumentum] —One- or two covering envelopes
which invest the ovule and later become seed coats.

In’ter-cel’lu-lar spaces — The cavities between adjoining cells.

In’ter-nodé [L. internodium] — Part of a stem between two successive nodes.

In’vo-lu’cre [L. involucrum] —A whorl of bracts subtending a flower or flower
cluster.

i18 LABORATORY OUTLINES FOR GENERAL BOTANY. —

I’so-bi-lat’er-al [Gr. isos +L. bilateralis] —A flower or organ which can be cut)
into equal halves by two planes, the halves of the one being unlike those. of 2
the other. ae

I’so-carp’ic [Gr. isos + karpé6s] — Having as many carpels in, a set as there are
petals, or sepals. aw,

I-sog’am-ous [Gr. isos + gamos] — Having gametes of equal size and appearance, .

I-so-gam’ete [Gr. isos + gameté] — One of a pair of equal gametes.

Ju’ve-nile organ [L. juvenilis] — An organ which is normal and functional in the iM
early stages of the individual but which later disappears, as the juvenile
leaves of certain seedlings. :

Kar’y-o-ki-ne’sis [Gr. karuon + kinein] — The process of indirect nuclear dene Hotes

Lac-tif’er-ous duct [L. lac+ ferre] — Ducts present in some plants containing alee
milky sap or latex. Seer as cite

La-mel’la [L. lamella] — One of the gills of a toadstool; a thin plate or layer as aot
the middle lamella of certain thick cell walls. Rice.

Lam‘i-na [L. lamina] — The blade of a leaf. :

Late wood — The part of the annual ring of wood produced at the latter aad Of
the growing season.

Latex [L. latex] — The milky sap of certain plants:

Leaf — An expansion arising from the axis or ‘branch of a sporaphie usually a
specialized to carry on the functions of photosynthesis and transpiration.

Leaf’let — One of the divisions of a compound leaf.

Leaf scar — The scar or cicatrix formed where the petiole of a leaf separates foe
the stem or twig.

Leaf trace— One or more vascular bundles which may be traced down from the
base of the leaf into the stem, continuing distinct for some time before unit-
ing with the stele. ; ;

Lem’ma [Gr. lémma]— The outer of the two flowering glumes inclosing a grass
flower. |

Len’ti-cel [L. lens, lentis] — A small, usually oval or round spot on the bark of a
twig or stem, produced by a special tissue of cells under a stoma and break-
ing thru the epidermis.

Lep’to-spo-ran’gi-ate ['Gr. leptos’ + sporos + aggeion] — Having the sporangia de--
veloped from superficial cells. ' wot

Leu’co-plast [Gr. leukos + plast6s] —A colorless plastid.

Li’chen [Gr. leichén] — A lichen is a plant structure formed by the association of a —
fungus and numerous alge, forming a rather definite appearance which bei Pe
simulates an individual. The lichen fungus is a slave-holder, living sym- > Ban:
botically with the alge as slaves. By some the word “lichen” is restricted ~ ya
to the fungus part alone, but as here defined, the lichen fungus is regarded
as a true fungus and the peculiar appearance or body, which is readily —
recognized in typical forms,—caused by the symbiosis of the two Organisms,
—is called the “lichen.”

Lid cells (of archegonium) — The cells at the tip of the neck of an archegonium
which open up to permit of the entrance of the sperms. eee Sei

Life cy’cle— The succession of stages in the life history of an organism from a Sais
beginning in the fertilized egg or spore until it reproduces cells of a Baie!
sponding nature. s ;

Life history — The succession of stages in the life of an organism from its tes ke
ginning until it disappears thru natural death or by division gives rise toa
new organism similar to itself. | yaivt

LABORATORY OUTLINES FOR GENERAL BOTANY. 119

2 -Lig’nin [L. lignum] — The chemical substance composing the walls of woody cells.
Lig’u-late [L. ligula] — Provided with or resembling a ligule; as a ligulate flower.
Lig’ ule — A strap-shaped organ; a triangular or somewhat elongated stipule-like
organ on the leaves of Isoetes and Selaginella.
Limb — The expanded part of a petal, sepal, or sympetalous corolla.
Linin [L. linum] — The substance of the achromatic network or spirem on which
the chromatin granules are held. .
Lip cells (of fern sporangium) — Specialized cells where the sporangium will break
: open.
Lip’o-chrome [Gr. lipos-+ chroma]— Any of several pigments usually yellow,
orange, or yellowish-red, nonsoluble in water, found in various — plants.
Liv’er-wort — Any plant belonging to the class Hepatic.
Lod’i-cule [L. lodicula] —One of the two or three minute hyaline scales in the
flowers of grasses, representing a vestigial perianth.
ane gi-tu’di-nal [L. longitudo] — Extending in the direction of the length.
Looped mother skein — The stage in karyokinesis in which the spirem is arranged
ea in definite loops just before it breaks in pieces.
_ Loose daughter skein — The stage in karyokinesis in which the separate daughter
chromosomes are beginning to unite, after the daughter star.
Lu’men [L. lumen] — The cavity of a tubular cell; a passage within the walls.
Ly-si’ge-nous cavity [Gr. luisis + génesis] — An intercellular space formed by the
breaking down or dissolution of adjoining cells.
-Male— An individual that produces spermatozoids but not oospheres directly from
the cells of its own body.
Male gamete — The spermatozoid or sperm.
Mal’for-ma’tion [L. malus + formatio] —Such organs or parts as show abnormal
growths due directly to some external condition in the life of the individual,
as a bud developed into an insect gall. |
- Med’ul- la‘ry ray [L. medullaris] —A strip of cells passing radially thru the wood
| from the pith or the various annual rings to the bark.
Meg’a-spo-ran’gi-um [Gr. mégas + sporos + aggéion] — A sparangium which pro-
duces megaspores; the ovule in seed plants.
- Meg’a- -spore [Gr. mégas +sporos|] — The larger of the two kinds of nonsexual
- spores produced in heterosporous plants. The megaspore develops into the
female gametophyte.
Meg’a- -spo ro-cyte [Gr. mégas+spdros-+kutos]—One of the cells in the
megasporangium in which the reduction division takes place and which
normally gives rise to four megaspores.
_ Meg’a-spo’ro-phyll [Gr. mégas-+ spéros + phullon] —The modified leaf which
_ bears the megasporangia. In seed plants usually called a carpel.
fs. Mer’i-stem [Gr. merizein] — A tissue of dividing cells; embryonic tissue.
& ‘Mer’i-ste-mat’ic [Gr. merizein] — Pertaining to the meristem or dividing tissue.
ae _ Mes’o- phyll [Gr. mésos + phullon] — The parenchymatous tissue in a leaf between
ee the upper and lower epidermis.-
Mes’ o-phyte [Gr. mésos + phuton] —A land plant: growing in ordinary conditions
sae of moisture.
Met’ a-ki-ne’sis [Gr. meta oe kinesis] — The stage in nuclear division after the forma-
tion of the mother star.
Met’ splice [Gr. meta + phasis] — The second general stage in karyokinesis in
_ which the individual chromosomes pass from a scattered condition in the
nuclear cavity to a definitely arranged mother star in the equatorial plane.

120 LABORATORY OUTLINES FOR GENERAL BOTANY.

Mi‘cro-pyle [Gr. mikros + ptle] — The small opening or pore at the outer end of
the ovule where the integuments come together over the nucellus.

Mi'cro-spo-ran’gi-um [Gr. mikros + sporos + gggéion] — A sporangium which Pro-
duces microspores; the pollensacks in seed plants.

Mi'cro-spore [Gr. mikrdéds + spdros] — The smaller of the two kinds of nonsexual
spores produced in heterosporous plants. The microspore develops into the
male gametophyte, called a pollen grain in seed plants.

Mi'cro-spo’ro-cyte [Gr. mikrés-+ sporos + kutos] —One of the cells in the mi-
crosporangium in which the reduction takes place and which usually gives

_rise to four microspores.

Mi‘cro-spo’ro-phyll [Gr. mikros + sporos + phullon] — The modified leaf which
bears the microsporangia. In seed plants usually called a stamen.

Mid’rib — The central rib of a leaf or other organ.

Mil’dew— Any of the mold-like parasitic fungi, as the downy mildews and
powdery mildews.

Mi-to’sis [Gr. mi’tos] — Indirect nuclear division. Same as karyokinesis.

Mold — Any of the saprophytic fungi consisting of loose hyphee, as the common
bread mold and the common blue mold. z

Mo-ne’cious [Gr. monos + oikia] — Having stamiriate and carpellate flowers on
the same plant.

Mon’o-cot’yl [Gr. mo’nos +kottle] — A plant having one cotyledon.

Mon’o-po’di-al [Gr. monos + pots] — Having a single and continuous axis, as a

twig which grows from a persistent terminal bud.

Mon’o-spo-ran’gi-ate [Gr. monos -++ sporos + aggeion] — Having only one kind af

_ spores in the flower; a flower with only stamens or carpels.
Mor-pho-log’ic-al [Gr. morphé + logos] — Of or pertaining to the form eat struc-
ture of an organ.
Moss — Any of the bryophytes except the liverworts and hornworts, as the bog-
. mosses, granite-mosses and true mosses.
Mother cell—A cell which divides into two daughter cells; or the parent cell of
two cells. |
Mother star — The star-like figure appearing in karyokinesis when the chromosomes
are in the equatorial plane.
Mul'ti-cel’lu-lar [L. multus + cella] — Composed of more than one cell.
Mush’room — Any large fungus belonging to the Ascomycete or Basidiomycete,
whether edible or poisonous, fleshy or otherwise.

Mu-ta’tion [L. mutatio] —A variation due to the presence of a specific hereditary |

factor or set of factors in the organism inherited in a definite way. .A sud-
den variation as distinguished from a gradual variation, the offspring differ-
ing from the parents in some well-marked hereditary character or characters.

Mu’tu-al-ism [L. mutuus] —The condition of symbiosis in which each of the
symbionts is of benefit in obtaining the food supply.

My-cel’li-um [Gr. mikes] — The entire mass of hyphae or threads which Bu up 3

the body of a fungus.

My-co rhi’za [Gr. mikes + hriza] — The mutualistic, oan association of a
fungus mycelium with the roots or other underground parts of a plant.
Nas’cent organ [L. nascens] — An organ or part at the beginning of its evolution
or at the beginning of its development in the race; or in its first stages of

evolution as compared with other homologous organs.

Neck (of archegonium) — The upper part of an archegonium thru which the |

sperms enter to unite with the egg.

age Sa oS be
Fe all
Tt eae owt Na Nes ae Re ea.

LABORATORY OUTLINES FOR GENERAL BOTANY. 121

Neck canal (of archegonium) — The passage, or row of central cells in the neck

of an archegonium,

Nec’'tar gland [Gr. néktar] — A gland which secretes nectar.

Nec’tary — A nectar-secreting organ.

Node [L. nodus] — The place where two internodes join, normally with a single

leaf or more.

Non-sex’u-al [L. non + sexus] — Being without sex; not producing gametes but

spores which develop without conjugation.

Nu-cel’lus [L. dim. of nux]— The incipient ovule, or the outer bad of the ovule

exclusive of the integuments.

Nu’cle-ar membrane [L. nucleus] — The layer of protoplasmic material surround-
ing the nucleus. |

Nu’cle-us [L. dim. from nux] — The dense, more or less spherical, complex, proto-

plasmic body present in the cell.

Nu-cle’o-lus [L. dim. of nucleus] A small rounded body contained in the

nucleus; one or more may be present.

On-tog’e-ny [Gr. 6n, Ontos + gignomai] — The history of the development of the

individual organism; the development of the individual.

O’o-go/ni-um [Gr. 06n-+ gdnos] —A simple ovary, cst consisting of a single

cell containing one or more eggs.

O’o-sphere [Gr. 06n + sphaira] — The unfertilized egg; the female gamete.

O’o-spore [Gr. 06n + sporos| — The fertilized egg.

O-per’cu-lum [L. operculum] — The lid at the tip of the sporangium of a moss or

other plant. |

Or’'der [L. ordo] —A group of plants consisting of one or more families; the

first general group of lower rank than the class.

Or’gan [Gr. Organon] —A part or structure of a plant fitted for the performance

of a definite function or set of functions.

_ Or-thot’ro-pous [Gr. orthos-+trépein] —A_ straight ovule, having the hilum and

micropyle at opposite ends. |

Os-mo’sis [Gr. osmds] — Diffusion thru membranes or partitions. The specific

relation which exists between solutions and the material of the separating

membrane, determining variable selection and permeability.

Os’ti-ole [L. ostiolum |] — The orifice opening into the cavity of a conceptacle, peri-

thecium, or similar structure.

Outer bark — The rough corky tissue developed from the cork cambiums outside

of the inner bark which is developed from the stelar cambium.

O’va-ry [L. ovum] — The female organ of reproduction; an egg-producing organ.

O’vu-la’ry [L. ovum] — The ovule-bearing part of a closed carpel or set of carpels.

O’vule [L. ovum] — The megasporangium of a seed plant which later develeps into

We a seed.

he _O’vu-lif’er-ous scale [L. ovum + ferre] — The peculiar outgrowth from the carpels

of some conifers at the base of which the ovules are borne.

Pa‘let [L. palea] — The inner of the two glumes inclosing the flower of a grass.

_ Pali-sade pa-ren’chy-ma [L. palus. Gr. parégchuma] — The tissue of vertically

‘4 elongated cells in the upper side of a leaf below the epidermis.

~ Pan’i-cle [L. panicula] — A compound inflorescence of the racemose type usually of

pyramidal form.

Pap’pus [Gr. pappos] — The bristles, awns, teeth, etc., on the top of an achene,

representing a calyx, or having the position of a superior calyx.

a

“Per’i-stome (of a moss) [Gr. peri-+ stoma] — The fringe of tects surromnding

122. LABORATORY OUTLINES FOR GENERAL BOTANY.

Par’a-site [Gr. parasitos] — An organism growing upon cehee faise plants or
-mals and absorbing their juices and tissues as food and thus causing then
injury. ! i A ate

Pa-raph’y-sis [Gr. para + phtsis] —A hair or a cores a he
paeariie organs. rags een

of hii (led cahicl or polygonal cells rich in S weiapacuie: content Be
Par’ the-no-gen’e-sis [Gr. parthénos + gignomai] — The germination and de
ment of an egg or other gamete without being fertilized” ‘Obs aes?
another gamete.

the denier of the hie
Pen’‘ta-cy’clic [Gr. pénte + kuklos] — Having five cycles. LENA Ss AN
Pen-tam’er-ous [Gr. pénte + méros] — Five -parted. ~° ee fe
sets en “minal [1s eae — Growing for 1 more than: two years or for many years, ay

Per'1- aie [Gr. periblema] — The layer of meristematic tissue lying. Detween oh
dermatogen and the plerome. f
Per’i-carp ['Gr. peri ++ karpos] — The wall of.a fruit; he ovulary eae
Per’i-derm [Gr. peri + dérma] — The ae tissue of ne outer bark derived :
growth of the phellogen. Phe Raa
Pe-rid'i-um [Gr. peridion] — The wall of a aor case in various Fungi, or the wall
of the fruiting body as in a puffball. F
Per’i-gyn’i-um [Gr. peri-+ guné] — The sack-like envelope Sieroumaiees ‘ne, ee
gonia in liverworts. The sack-like envelope around the ovulary: of a Carex
flower. Darin:
Pe-rig’y-nous [Gr. peri + guné| — Having ihe sepals, petals, and stamens borne on
a disk or hypanthium surrounding the gynecium.

- the mouth of a moss sporangium when the operculum is removed, -
Per-i-thé-ci-um [Gr. peri +théke] — A flask-shaped body with an ostiole: contain
ing asci; a certain kind of ascocarp.
Pet’al [Gr. pétalon] — One of the leaves or segments of the corolla:
Pet’i- oe [L. petiolus] — The stalk of aleat:

tod eeihen? asia i aaeae or saprophyte. ct
Phel’lo-derm [Gr. phell6s + dérma] — A secondary cortical - tissue developed ¢ ‘
the inside of and from the phellogen.

Phel'lo- salt shee phellos + genés] — The cork cambium ; a ee _ me

and hee companion cells; in a dicotyl the phloem forms art oft
bark. 1
Pho-to-syn’the-sis [Gr. phos-—+ stinthesis] — The process of Bere oe

bolism by which carbohydrates are formed from water han:

Pho-tot’ro-pism [Gr. Shas een 2s response of plants to “ight, a
changes in growth and position [heliotropism]. “ cet eas
Phy-co-cy’an [Gr. phikos + kuanos] a blue coloring matter found 1
green algae.

oe QUTLINES FOR Cee BOTANY. 123

Phy: ae e- ny [Gr. eH e oisnestel — The ce of the development of the
_. race or phylum to which an organism belongs, in distinction from ontogeny.

: Phy'lum (of plants) [Gr. philon] —One of the great or fundamental natural

: groups of plants. The plant kingdom can be divided into fifteen phyla.

Phys -o-log’ic-al [Gr. phusis + logos] — Pertaining to the ‘functions and activities

of organisms.

Pi’ le-us [L. pileus] — The expanded upper portion or cap of many of the fungi.

Pi-liffer-ous layer [L. pilus-++ ferre] — The external layer of cells in a young

root, giving rise to the root hairs; the epidermis of a root from which root

hairs develop.

Pith — the soft parenchymatous oe in the center of a stem; the general ground

tissue thru which scattered vascular bundles pass.

Plank’ ton [Gr. plagkton] — The minute free floating or swimming plants and ani-

mals of a body of water; the secondary plankton includes the larger surface

floating plants and also such as are commonly torn loose and float in the

et water.

Plan’ ‘o-gam’ete [Gr. eee + gamein] — A motile gamete.

Plas- -mo di-um ['Gr. plasma] — A jelly-like mass of fused naked, ameboid cells, as

_ the plasmodium of a myxomcete.

Plas- Pie: sis [Gr. plasma —-+lusis] — The contraction or shrinkage of the proto-
plasm in a living cell due to the rapid loss of water by exosmosis. |

Pies tid [Gr, plastis] —One of the small granules or color bodies found in the

cytoplasm of plant cell. They are divided into chloroplasts, chromoplasts

_ and leucoplasts,

Ple’ rome [Gr. pleroma]— The central cylinder or column of tissue in an em-

aS, bryonic plant. _

Plu’ mule [L. plumula] — The bud or growing point of an embryo plant in the seed.

Plat T1- -loc’u- lar [L. plus, pluris + loculus | — Having several cavities or loculi; in
. algze, having many cells separated by walls = multicellular, as plurilocular

sporangia.

Po’ lar-nu’cle-i— The two nee nuclei present in most female gametophytes of the

_ Anthophyta which together with a spermatozoid conjugate to form the

: definitive nucleus which gives rise to the endosperm of the seed.

o Po'lar ra’di-a’tions — The radiations which surround the poles of the spindle during

_ karyokinesis and later, near the end of nuclear division, the daughter nuclei.

S ‘Poles of spin’dle — The two points in the karyokinetic figure to which the spindle

; fibers converge, and often surrounded by radiations.

Par len ae ber — The cavity in the tip of the ovule of certain ices gymnosperms,
into which the pollen is received after passing thru the micropyle.

~

he So ccule ob the ne
‘[Gr. poltis + stéle] — Having several steles.

"tex — The periblem or the tissue derived directly from it; the tissue
em between the vascular bundles and the epidermis.

\

124 LABORATORY OUTLINES FOR GENERAL BOTANY.

Pri-mor’di-um [L. primordius] —A nascent organ; an organ in its first stages of
evolution as compared with other similar organs.

Pro-cam’bi-um [L. pro + cambire] — The young tissue of a vascular bundle bette
tts cells have begun to be differentiated, or the tissue from which the original
vascular bundles are developed.

Pro-em’bry-o [Gr. pro’ +4 émbruon] — The early embryo before its differentiation.
It is usually differentiated into a suspensor and the embryo proper.
Pro-my-ce’li-um [Gr. préo-+mukes]—The short hyphal filament or basidium

produced by a germinating chlamydospore, as in the rusts and smuts.

Pro’phase [Gr. pro’ + phasis] — The first general stage in karyokinesis in which ON a
the chromatin network is transformed into a spirem and thrown into loops. __ ag Ae

Pro’to-ne’ma [Gr. protos + néma] — The filamentous green alga-like body or em- ¢
bryonic thread, which develops from the spores of certain ferns and
bryophytes or from some part of a moss plant. © Bi Be

Pro’to-plasm [Gr. protos + plasma] — The living substance found in the cells of Sheet ham
plants and animals. 3 ate

Pro’to-plas’mic con’ti-nu’i-ty — Having the protoplasts connected by BU .
strands which pass thru the cell wall.

Pro’to-plast [Gr. protos + plastis] — The protoplasmic cell contents, exclusive of
the cellulose wall.

Pro’'to-ste’le [Gr. protos + stéle — The solid stele characteristics of most roots, of eae
the earliest portions of stems and in some petriodophytes of the whole of ts

the axis. pe,

Pseu’do-po’di-um [Gr. pseudés + pous]—A scaleless branch of a moss bearing San
gemmae or a sessile sporangium. hc aed

Puff’ball— Any fungus belonging to the Lycoperdacee or similar related forms. ache

Pul’sa-ting vac’u-ole—A contractile cavity or cell organ present in some lower
organisms.

Pyc-nid’i-um [Gr. puknos] — A perithecum-like body bearing conidiospores, present
in certain fungi.

Pyc’ni-um [Gr. puknés] —A perithecium-like body or receptacle bearing pycno-
spores.

Py-re’noid [Gr. purenoeidés] — A transparent refractive proteid body found in the
chromotophores of certain alge. The pyrenoids serve as centers for the
deposition of starch.

Pyr’i-form [L. pyrum + forma] — Shaped like a pear.

Qual’i-ta-tive di-vi’sion — Nuclear division in which there is a segregation of
chromatin material of distinct kind or a segregation of entire chromosomes,
not merely the daughter parts.

Quan’ti-ta-tive di-vi’sion— Nuclear division in which daughter chromosomes, de- oe.
rived from mother chromosomes, are segregated. ae ita.”

Ra-chil’la [Gr. hrachis] — The axis of a spikelet on which the flowers are arranged.

Ra’chis [Gr. hrachis] — The axis of a spike, or raceme, on which flowers or spike-
lets are arranged; also the axis of a compound leaf.

Ra’di-al section [L. radius] —A section cut longitudinally thru the center of are ee
stem.

Rad’i-cle [L. radicula, dim. of radix] — The incipient stem and root in an embryonic
plant. Hae

Ra’phe [Gr. hraphé] — A ridge or seam along the side of a seed. . i

Raph’i-des [Gr. hraphis] — Minute, usually needle-shaped crystals often recurring |
in bundles in the cells of certain plants,

he

LABORATORY OUTLINES FOR GENERAL BOTANY. 125

Ray flower — One of the marginal or ligulate flowers in the head of a composite.

3 Re-cep’ta-cle [L. receptaculum] — The stem or axis which bears the floral organs;

Tks a special branch which bears the reproductive organs in certain alge.

Re-ces’sive character [L. recessio] —A character possessed by one of the parents

: of a hybrid which may not appear in the hybrid but is nevertheless transmit-
ted to the following or a later generation.

Re-duc’tion division— The division in a sporocyte, oocyte, or spermatocyte in
which the bivalent chromosomes are segregated into univalents, and in which
the reduction number appears during the development of the bivalents.

~Re-flexed’ [L. reflexus] — Bent backward abruptly.

Re-pro-duc’tion [L. re-+ producere] — The process by which organisms give rise

to offspring.

Resin duct [L. resina, ductus] — A passage or tube containing resin.

Res’-pi-ra’tion [L. respiratio] — The chemical changes taking place in all living
cells whereby organic constituents are decomposed largely as a result of the
action of enzymes, liberating energy, water, and carbon dioxide. In ordinary
respiration, the external manifestations are the taking into the cell of the
free oxygen of the air and the giving off of carbon dioxide.

Resting nucleus — A nucleus not in the stage of division.

-Re-tic’u-late [L. reticulatus[ — Arranged as a network.

Re’tro-gres’sive organ" [L. retrogressus] — An organ which is passing from a higher
to a lower or less perfectly deveioped condition or state of organization.

Rhi’zoid ['Gr. hriza] — A filamentous outgrowth from the thallus or gametophyte,
usually functioning as an organ of attachment.

Rhizome [Gr. hrizoma] — An underground stem.

_Root — An _ absorptive and supporting organ of the sporophyte usually under-
ground.

Root-cap — A special tissue covering the root tip, developed from the calyptrogen.
Root hairs — Slender thread-like epidermal absorbing cells or filaments develop-
ing on roots just back of the growing point, from the piliferous layer.
Ro-setté [L. rosa] —A closely crowded and symmetrically arranged cluster of

leaves at the end of a branch or stem, usually close to the ground.

Ru’di-ment — A rudimentary organ.

Ru’di-men’ta-ry (organ) [L. rudimentum] — An organ or part in the initial, incip-
ient, or incomplete stage of development; or one that has become reduced
either in the history of the race or of the individual.

Rust (plant rust) — Any parasitic fungus belonging to the order Uredinales.

Sap-ro-phyte [Gr. saprés-+ phuton|—-A plant which grows on dead organic
matter.

Sap’wood — The part of the wood, next to the cambium, thru which the water

mainly passes up the stem; the alburnum.

fSealat i form. [1. scalaris] —Resembling a ladder; having transverse bars or —

markings like the rounds of a ladder.

- Scale— A highly modified dry leaf as in a winter bud; a flat more or less mem-

_ braneous outgrowth from a leaf or stem. The leaf-like expansions on the

gametophytes of mosses and liverworts.

ni-zog’en-ous (cavity) [Gr. Schi’zein + génesis] — Produced by the splitting of

Ws cell walls as contrasted with Tee notes

a 2, eae eel Palle: as a fiber cells in the ale
el’-lum [L. Scutum] — A shield- like outgrowth at the side of the embryo as
‘in the embryo of Zea.

126 LABORATORY OUTLINES FOR GENERAL BOTANY.

Sec’ond-a-ry cor’tex [L. secundarius] — The tissue developed on the inner side
of the cork cambium, the phelloderm.

Seed — The ripened ovule with the sporophyte embryo and remains of the female
gametophyte in the anthophytes often with abundant endosperm. The seed
is not to be compared. with a spore. In the anthophytes it contains parts
of three generations —the parent sporophyte, the parent female gametophyte
and the embryonic sporophyte together with more or less endosperm.

Seed plant — Any plant belonging to the series Spermatophyta.
Self-fertilization — The union of a sperm with an egg produced by the same
hermaphrodite individual. :
Self-pollination — The pollination of a stigma or ovule by male gametophytes pro-

duced on the same sporophyte as the stigma.
Self-pru’ning — The process by which living buds and twigs are separated from a

plant.
Sep’al [NL. sepalum] — One of the leaves or divisions of a calyx.
Sep’tum [L. septum] — A partition or separating wall.

Se’ta [L. seta] — The stem or stalk of a moss sporophyte.

Sex’u-al’i-ty [L. sexus] — The quality or state of being distinguished by sex.

Sex’u-al organs [L. sexus] — The organs which produce the gametes or eggs and
sperms.

Sex’u-al re-pro-duc’tion — Reproduction by means of eggs and sperms or by iso-
gametes.

Sex’u-al spore — A spore formed by the union of two gametes.

Sheath (of a filament) (of a leaf) — A thickened outer wall as in some blue-green
alge; the hase of a leaf below the blade investing the stem as in grasses.

Shoot — A stem with its leaves as distinguished from the root.

Sieve-plate — The thin perforated wall between the adjacent cells of sieve tubes.

Sieve-tube — A tube of sieve cells placed end to end in rows and separated by
sieve plates.

Si-lic’i-fied [L. silex] — Impregnated with silica.

Si’pho-no-stéle [Gr. siphon + stéle] — A hollow cylindrical steel with or without
pith.

Slime-mold — A plant belonging to the Myxophyta.

Smut — A plant belonging te the orders Ustilaginales and Tilletiales.

So-re’di-um [Gr. sords] —A small granular body produced on the surface of a
lichen thallus.

So’rus [Gr. soros] —A cluster of sporangia in the ferns.

Spat’u-late [L. spatula] — Widened at the top like a spatula.

Spe’cies (of plants) [L. species] — A group of more or less similar individuals
having a common ancestry and interbreeding readily, with production of fer-
tile offspring. ‘

Sperm [Gr. spérma] —A male gamete; the spermatozoid.

Spermary [Gr. spérma]—An organ which produces spermatozoids; the male
reproductive organ.

Sper-ma’ti-um [Gr. spérma] —A non-motile spermatozoid, as in red alga, lichens ©
and fungi, ee

Sper’ma-tog’e-nous [Gr. spérma + gigomail] — Sperm-producing.

Sper’ma-to-zo’id [Gr. spérma -+ zoon + eidos] — The male gamete.

Sper’mo-go’ni-um [Gr, spérma + goné] — An organ which produces spermatia.

Spike — An elongated rigid inflorescence with sessile or nearly sessile flowers, ©

oo ee FOR GENERAL BOTANY. ‘aes WA:
i. Spike’ ieee small spike ; Paes oes ultimate flower-cluster of the inflorescence
: of grasses and sedges. | ; es
_ Spin’dle— The spindle-shaped figure of fibers of achromatic substance, “formed
as during karyokinesis, to which the chromosomes are attached.

‘Spi ral wood vess’el— An elongated wood cell containing one or more us
oe thickenings of lignin in the wall. 5 .

Spr’ rem [Gr. speirema] — The thread of chromatin formed in hee nucleus. from
Ae ‘the chromatin network during nuclear division.
_ Spon’gy pa-ren’chy-ma — The layer of loosely arranged parenchyma cells. in "the

under side of the leaf. ;

angia.
Spo-ran’gi-um [Gr. sporos + aggeion] — A spore-producing organ,
_ Spore [Gr. spdros] — A modified reproductive cell. : |
es _ Spore- ling ['Gr. sporos + A. S. ling] — A young plant or oe developing from
Bas a spore on the ground, not in a seed.
: Spore tetrad — The four spores resulting from the two reduction divisions, before
oy their separation. ‘ ve fs
: ‘Spo- rid‘i-um [L. Sporidium from Gr. spora]—A small spore ees on ie.
: promycelium or basidium coming from a teleutospore of one of the Telio- -
spore; probably a INE of basidiospore. : 7
Spo’ ro-carp ‘[Gr. sporos + karpos — A carpel-like, or enclosed, spore-bearing organ. |
Spo’ro-cyte- iG sporos + kutos] —In plants, any cell which undergoes the reduc-_
. tion division in producing non-sexual spores. Beau fe
Spo’ro-phore [Gr. sporos + phérein — An organ or structure ich deem spores.
-Spo’ro-phyll [Gr. spodros + phuillon] — A spore-bearing leaf. ihe
Spo’ro-phyte [Gr. sporos 4- phuton] — The nonsexual generation of plane
i Sprout (to) = To continue growth, as the sprouting of a bud; to break out of the
seed and continue growth, as the sprouting of a seed —to be distinguished
from germination, which see. eye
Stalk — The stem or main axis of a plant; the petiole or peduncle, or any similar
part ea
Stalk cell (of pollengrain) — The cell at the back of the spermatogenous ai and a
sister cell to it. .
Sta’ men [Gr. stémon, L. stamen]—the organ of a flower which produces micro-
sporangia, which contain the microspores which later develop into pollen
grains; the microsporophyll of seed plants.
ii Stam’i-nate [L. staminatus | — Containing or producing stamens; having stamens
only or staminate flowers only. .
a carbohydrate produced in plants and esl found in «the form of

‘Spo- -ran gi-o-phore [Gr. sporos + aggeion + phérein] — An organ Relea ‘spor- a ee

128 LABORATORY OUTLINES FOR GENERAL BOTANY.

Stip’u-lar scar [L. stipula]— The mark made on the bark by some deciduous
stipules.

Stip’ule [L. stipula] —A bract-like appendage at the base of the petiole of many
leaves. :

Stipe [L. stipes] — The stalk of a toadstool or similar structure.

Sto’lon [L. stolon] — A basal branch rooting at the nodes.

Sto’ma [Gr. st6ma, stomata] — The transpiring pores in the epidermis of the

higher plants.

Stro’bil-us [Gr. strobilos] —A primitive flower or cone, as in a horsetail or pine.

Style [L. stilus, Gr. sttilos] — The narrow elongated part of the carpel or of the
united carpels, between the ovulary and stigma.

Sub-merged’ [L. submergere] — Growing under water.

Sub’ter-ra’ne-an [L. sub-+terra] — Being or growing under the surface of the
ground.

Sug’ar—A sweet, transparent, soluble, crystallizable carbohydrate produced in
plants thru photosynthesis.

Sus-pen’sor cells [L. sub + pendere] —The row of cells which attach the young

embryo, at the radicle, to the inner wall of the ovule.

Sym’bi-ont [Gr. sumbidn] — One of the two individuals or species which live to-
gether in the symbiotic relation or condition.

Sym-bi-o’sis [Gr. sumbidsis] — The living together of two or more dissimilar
organisms in more or less intimate association, including mutualism, helotism,
and parasitism.

Sym-met’ric-al [Gr. sun + métron] — Applied to an organ or part which can be
divided into equal halves by one or more planes.

Sym-po’di-al branching [Gr. sin + pots, podés] —A system of branching in which
the main axis is made up of a series of lateral branches because of the
self-pruning or withering of the terminal bud.

Syn-ap’sis ['Gr. su/napsis] — The fusion of simple chromosomes into multiple ones,
usually of a bivalent value.

Synaptic mates. The two corresponding univalent chromosomes which conjugate
to form bivalents in the prophase of the reduction division.

Syn-er’gid [Gr. sunergds] —One of the two cells lying above the egg in the
female gametophyte of Anthophyta. The two synergids and the egg con-
stitute the egg apparatus.

Syn’i-ze’sis [Gr. syni’zesis] — The unilateral or central contraction of the chro-

matin usually seen in the nucleus during the early stages of the reduction
division. )
Tan-gen’tial (section) [L. tangens] —A section cut near the surface of a stem or
other structure.
Tan’nin, Tannic acid— An astringent chemical substance widely diffused thru the
cells of plants, as in oak bark, oak galls and various leaves and fruits.

Te’li-o-spore [Gr. te’los + sporos] —One of the thick-walled chlamydospores or

winter spores developed in the final stage of the life cycle of a rust fungus.
Te’li-um [Gr. télos, téleos] — The sorus of the teliostage in the rust fungi.

ra
ee

Tel’o-phase [Gr. télos + phasis] — The last general stage of karyokinesis during — a ea

which the daughter chromosomes are transformed into a resting network. ©
Tet-ra-cy clic [Gr. téssares + kuiklos] — Having four cycles, as in certain flowers.

Tet’rad [Gr. tetras] —A collection of four things, as four spores produced from —

one grandmother cell.
Te-tram’er-ous [Gr. téssares + méros] — Four-parted.

pee OUTLINES FOR GENERAL BOTANY. © 129 aes

* a Tet’ ra-spo-ran’gi-um [Gr. téssares + sporos + aggeion] —A ee which Brey at
-——s duces tetraspores, as in the red alge. Che
Tet ra-spore [Gr. téssares + spdros}] — A nonsexual spore, one of a group of four nce
spores resulting from a reduction division as in the red alge.

hal’ lus [Gr. thallos] — The plant body of a thallophyte, or of the Soo of
the archegoniates.

tissue in which “he ene walls are not absorbed. Tracheids een have
bordered pits and are very characteristic of conifer wood.
| Trans- formed organ — One which shows a distinct change in the individual from >
one type of normal structure to another; as a stamen developing into a petal.

2 ‘Tran’ spi-ra’tion [L. trans + ee — The process of giving off water vapor thru
ies bie stomata,
Trans-verse’ septum [L. transversus, septum] — A crosswall or partition. i, euene
rans-verse’ sec ‘tion — A section cut at right angles to the long axis; a cross Ke
peersection;
ich’ o-gyne [Gr. thrix, trichos + guné] — The slender, hair-like prose at the tip
of the oogonium, as in fed alge. hire
Trich’o- phore [Gr. thrix, trichos + phérein] — The base of the type of oogonium — ES a)
which bears the trichogyne, as in the red alge. It contains the egg. es
aoe -cy clic [Gr. tri + kuklos] — Having three cycles. | es
‘Tri’mer-ous [Gr. tri+ méros] — Three parted.
Eri’ ple fu’sion [L. triplus, fusio] —The union of the two polar nuclei and a

sperm to form a definitive nucleus from which the endosperm is developed.
‘Trip- loid [Gr. tripl6os] — Having a triple or 3x number of chromosomes.
he _ Tube cell, tube nucleus — The cell in a pollengrain which develops into the pol-
2°) -ientube.
Aad ber- -ous [L. tuberosus] — Consisting of or bearing tubers, or thickened under-
ground stems.
Tu bu-lar flowers [L. tubulus] — The central disk flowers in a composite as dis:
_ tinguished from the ray flowers.
oe #0 os-cel lular [L. unus + cella] — Consisting of but one cell or protoplast. |
ay ‘ni-loc’u-lar [L. unus + loculus] — With one cavity.
_ U-nt-sex’u-al [L. unus-+sexus] — Having only ovaries: or spermaries on one
z individual; being purely male or female. . ;
: U-niv’a-lent (chromosome) [L. unus-—valens] —One of the double number of
fe rece pee their union into bivalents in the reduction chase

hich presents the end view of

»

ee oS,
S AS

130 LABORATORY OUTLINES FOR GENERAL BOTANY.

Ver-na’tion [L. vernatio| — The arrangement of the leaves in the bud.

Vas’cu-lar bun’dle [L.. vasculum]— A bundle of tissue in the higher plants con:
taining the xylem and phloem, or the wood cells and bast cells.

Vas’cu-lar pear ny plant having true vascular tissue in the sporophyte.

Veg’e-ta-tive prop’a-ga’tion [L. vegetatio, propagatio] — Reproduction by means of

organs or cells derived directly from the parent individual. eS
Vien [L. vena] —One of the branches of the vascular portion of leaves or other
organs. | te

Ve-na’'tion [L. vena] — The arrangement of the veins. - pee

Ven’ter [L. venter] — The base of an archegonium containing the egg. =

Ven'tral [L. ventralis] — Pertaining to the venter, or to the lower ae in a
dorsiventral organ.

Ve-sic'u-lar [L. vesicula] — Having the form or structure of a vesicle, or bladder-_ See
like body. oe
Ves’sel (xylem) [L. vas] —A long tube in the xylem formed of superposed cells —
which have lost their end walls and are usually marked with dots, Pitay
rings, or spirals. These vessels are often called trachee. A:

Ves'tige [L. vestigium]— An organ or part which was normally developed in te
past history of the race, but which has become rudimentary.

Wood — The xylem;; the lignified part of a stem.

Wood fiber — A slender cylindrical or prismatic cell in the xylem usually vite tHe
ends tapering to points.

Wood pa-ren’chy-ma — A thick walled parenchyma in the secondary xylem.

Xe’ni-a ['Gr. xénios] — The immediate influence of pollen on the endosperm in
hybridization caused by the union of the second sperm of the pollengrain
with the two polar nuclei of the female gametophyte and manifesting itself
as color, etc., in the grains of corn and various other plants.

Xéni-o-phyte [Gr. xénios + phuton] — The endosperm of Anthophyta, usually con-
sisting of cells with the 3x number of chromosomes because it results from

7 a triple fusion. The xeniophyte is, therefore, usually a triploid generation.

Xe’ro-phyte [Gr. xerds + phutén] —A plant growing in dry or desert conditions.

Xylem [Gr. xulon] — The part of the vascular bundle which contains the wood =
cells, as distinguished from the phloem.

Yeast —A plant belonging to the Saccharomycetales. -

Zo'o-gloe’a [Gr. zoon + gloios] —A mass of bacteria imbedded in a gelatinous
substance. ;

Zo’o-spo-ran’gi-um [Gr. zdon-+ sporos + aggeion] —A sporangium which pro-
duces es

Zo’o-spore [Gr. zOon + sporos] —A motile spore provided with one or more cilia af]
or flagella. iG

Zo'o-zyg’o-spore [Gr. zoon-+ zugon + sporos] — A zygospore procaine bY the
union of two similar zoospores. ae

Zyg’o-mor’phic [Gr, zug6n + morphé] — Applied to a flower or organ
be cut into similar halves by only one plane. Taek

Zyg’o-spore [Gr. zugon + sporos] —A spore formed by the union | of
nearly similar gametes. a

Zy’gote [Gr. zugotds] —A spore formed by the conjunction of two ) gamet
sexually formed spore.

e

aya coe

3

G