Alphonso Wood.

The American botanist and florist: including lessons in the structure, life, and growth of plants; together with a simple analytical flora, descriptive of the native and cultivated plants growing in the Atlantic division of the American union online

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false partitions. Thus the pod of Thornapple (Datura) becomes 4-celled from a 2-celled
ovary; and the longer pods of some Leguminous plants have cross-partitions formed
between the seeds.

146. The Pericarp. The fruit consists of the pericarp and
the seed. The pericarp (wspi, around) is the envelope of the
seeds, consisting of the carpels and whatever other parts they
may be combined with. It varies greatly in texture and sub-
stance when mature, being then either dry, as the Pea-pod, or
succulent, as the Currant. Dry pericarps are membranous, or
coriaceous (leathery), or woody. Succulent pericarps may be
either wholly so, as the Grape, or partly so, as the Peach and
other stone fruit.

147. With very few exceptions the pericarp encloses the seed
while maturing. In Mignonette (1G5), however, it opens, ex-



posing the seed, immediately after flowering. The membranous
pericarp of Cohosh (Leontice) falls away early, leaving the seed
to ripen naked. In Yew (Taxus) the seed is never enclosed
wholly by its fleshy pericarp ; but in most of the other Coni-
ferse, the close-pressed, carpellary scales cover the seeds. One-
seeded fruits, like those of Butter-cups, etc., are liable to be
mistaken for naked seeds.



Capsule, 167, of Scroplmlaria, 2-colled; 168, of Datura Stramonium; 169, of Iris; 170, showing its mode
of dehiscence (loculicidal). 171, of Colchicum, 3-celled. 172, Regma, ripe fruit of Gerauium, the carpels
(cocci) separating from the axis and bending upward on the elastic styles.

148. Dehiscence. The fleshy pericarp is always indehiscent.
Its seeds are liberated only by its decay, or bursting in germi-
nation. So also in many cases the dry pericarp, as the acorn.
But more commonly the dry fruit, when arrived at maturity,
opens in some way, discharging its seeds. Such fruits are de-
hiscent. Dehiscence is either valvular, porous, or circumscissile ;
valvular, when the pericarp opens vertically along the sutures,
forming regular parts called valves. These valves may separate
quite to the base, or only at the top, forming teeth, as in Chick-
weed. We notice four modes of valvular dehiscence, viz. :

1, Suttiral, when it takes place at the sutures of any 1 -celled
pericarp, as Columbine, Pea, Violet.

2, Septlcidal (septum, partition, ccedo, to cut), when ft takes
place through the dissepiments (which are double, 132). The
carpels thus separated may open severally by sutures (Mallows),
or remain indehiscent, as in Vervain.

3, Loculicidal (loculus, a cell, ccedo, to cut), when each carpel


opens at its dorsal suture directly into the cell (Evening Prim-
rose, Lily). Here the dissepiments come away attached to the
middle of the valves.

4. Septtfragal (septum, suidfrango, to break), when the valves
separate from the dissepiments which remain still united in the
axis (Convolvulus.)


Dehisceuce; 173, septicidal; 174, ioculiddai, 175. septifragal.

149. Porous dehiscence is exemplified in the Poppy, where
the seeds escape by orifices near the top of the fruit. It is not
common. Circumscissile (circumscindo, to cut around), when
the top of the ovary opens or falls off like a lid, as in Jefferso-
nia, Henbane, Plantain. Some fruits, as the Gerania and Um-
belliferae, are furnished with a carpophore, that is, a slender col-
umn from the receptacle a fusiform torus, prolonged through
the axis of the fruit, supporting the carpels.

Jfeview. 143. Origin of the fruit. Death of the flower. What parts may survive ? In
Apple? Genm? Potato? Strawberry? 145. A rule and an exception. Instance in Oak-
Birch. What change in Thornapple ? 140. Constituents of the fruit. Etymology of
pericarp. Texture. 147. Open pericarps. 148. What is dehiscence and indehiscence.
Three general modes of dehiscence. Four modes of valvular dehiscence. 149. Define
Porous dehisceuce Circumscissile. What is a carpophore ? Illustrate by 172, 171.



150. The morphology of the pericarp is exceedingly diversified ; but it will suffice the
learner at first to acquaint himself with the leading forms only, such as are indicated iu
the following synopsis and more definitely described afterward.

The following is a synopsis of the principal forms of Pericarps, for the blackboard.


1. Free Fruits (formed by a single Flower}.

* Pericarps iiideliiscent.

t With usually but one seed, and
Uniform, or 1-coated.

1. Separated from the seed.

2. Inflated, often breaking away.

3. Inseparable from the seed.

4. Invested with a cupule (involucre).

5. Having winged appendages.

$ Double or triple-coated, fleshy or fibrous.

6. Three-coated. Stone cell entire.

7. Two-coated. Stone cell 2-partcd.

8. Drupes aggregated.
t With two or more seeds,

Immersed in a fleshy or pulpy mass.

9. Kind membranous.

10. Rind leathery, separable.

11. Kind hard, crustaceous.

$ 12. Inclosed in distinct cells.

* Pericarps dehiscent.

t 13. Dehiscence circumscissile, seeds so .
t Dehiscence valvular or porous ;
% Simple, or 1-carpelled,

14. Opening by the ventral suture.

15. Opening by both sutures.
1(5. Legume jointed.

% Compound pericarps ;

17. Placentie parietal with two cells.

Silique short.

18. Placentie parietal only when 1-cclled.

19. Capsule with carpophore and elastic st;

Achenium (Buttercups).
Utricle (Pigweed).
Caryopsis (Grasses)
Glaus (Oak).
Samara (Ash).

Drupe (Cherry).
Tryma (Walnut).
Etaerio (Raspberry).

Berry (Gooseberry).
Hesperidium (Orange).
Pepo (Squash).
Pome (Apple).

Pyxis (Henbane).

Follicle (Columbine).
Legume (Pea).
Loment (Desmodium).

Silique (Mustard).
Silicle (Shepherd's Purse;.
Capsule (Flax).
les. Regma (Geranium).

2. Confluent Fruits (formed of an Inflorescence).

* 20. With open carpels aggregated into a cone.

* 21. With closed carpels aggregated into a mass.

Strobile (Pine).
Sorosis (Pineapple.)

151. The achenium is a small, dry, indehiscent pericarp, free
from the one seed which it contains, and tipped with the remains
of the style (Buttercups, Lithospermum).

The double achenium of the Umbcllifene, supported on a carpophore, is called cremo-
carp (177). The 2-carpelled achenium of the Composite, usually crowned with a pappus,
is called cypsela (178).

The achenia are often mistaken for seeds. In the Labiatte and Borrageworts they are
associated in fours (141). In Geum, Anemone, etc., they are collected in heads. The
rich pulp of the Strawberry consists wholly of the overgrown receptacle, which bears Ihe
dry achenia on its surface (184).

152. The utricle is a small, thin pericarp, fitting loosely upon
its one seed, and often opening transversely to discharge it
(Pigweed, Prince's Feather).



153. Caryopsis, the grain or fruit of the Grasses, is a thin, dry,
1-seeded pericarp, inseparable from the seed.

154. Samara; dry, 1-seeded, indehiscent, furnished with a
membranous wing or wings (Ash, Elm, Maple).



155. GlanSy or nut; hard, dry, indehiscent, commonly 1-seeded
by suppression (145), and invested with a persistent involucre
called a cupule, either solitary (Acorn, Hazelnut) or several
together. (Chestnut, Beechnut).

156. Drupe, stone-fruit; a 3- coated, 1-celled, indehiscent peri-
carp, exemplified in the Cherry and Peach. The outer coat
(epidermis) is called the epicarp ; the inner is the nucleus or
endocarp, hard and stony ; the* intervening pulp or fleshy coat
is the sarcocarp (tfap^, flesh). These coats are not distinguish-
able in the ovary.

157. Tryma, a kind of dryish drupe, 2-coated; the epicarp
fibro-fleshy (Butternut) or woody (Hickory) ; the nucleus bony,
with its cell often deeply 2-parted (Cocoanut).

158. Etcerio, an aggregate fruit consisting of numerous little
drupes united to each other (Raspberry) or to the fleshy recep-
tacle (Blackberry).

159. Berry, a succulent, thin-skinned pericarp, holding the
seeds loosely imbedded in the pulp (Currant, Grape).

160. ffczperidium,) a succulent, many-carpelled fruit; the rind



thick, leathery, separable from the pulpy mass within (Orange,

161. Pepo, an indehiscent, compound, fleshy fruit, with a
hardened rind and parietal placenta (Melon).

162. The pome is a fleshy, indehiscent pericarp, formed of
the permanent calyx, containing several cartilaginous (Apple)
or bony (Haw) cells.

163. The pyxis is a many-seeded, dry fruit, opening like a lid
by a circumscissile dehiscence (Plantain, Henbane, JefFersonia).

164. The follicle is a single carpel, 1-celled, many-seeded,
opening at the ventral suture (Columbine, Larkspur, Silk-grass).



/VV*.-185. Etairio of Rubus strigosus (Blackberry). 186, Pcpo; section of Cucumber. 187, Berry
Grape. 188, Pome, Oata^us (Haw). 189, Pyxis of Jeffersonia. 190, Legume of Pea. 191, Loment of
Desmodium. 192, Silique of Mustard. 193, Silicic of Cupsella.

165. The legume, or pod, is a single carpel, 1-celled, usually
splitting into two valves, but bearing its 1 GO seeds along the
ventral suture only, in one row, as in the Bean and all the
Leguminosae. It is sometimes curved or coiled like a snail-shell
(Medicago). The loment is a jointed pod, separating across
into 1-seeded portions (Desmodium).

166. Silique. This is also a pod, linear, 2-carpelled, 2-valved,
2-celled by a false dissepiment extended between the two parie-
tal placenue. To this false dissepiment on both sides of both



edges the seeds are attached (Mustard). The silicic is a short
silique, nearly as wide as long (Shepherd's Purse). The silique
and silicle are the peculiar fruit of all the Crucifene.

167. Capsule (casket.) This term includes all other forms of
dry, dehiscent fruits, compound, opening by as many valves as
there are carpels (Iris), or by twice as many (Chickweed), or by
pores (Poppy).

168. The Regma is a kind of capsule like that of the Gera-
nium, whose dehiscent carpels separate elastically, but still
remain attached to the carpophore.

169. Strobile, or Cone; an aggregate fruit consisting of a
conical or oval mass of imbricated scales, each an open carpel
( $ flower), bearing seeds on its inner side at base, i. e., axillary
seeds (Pine and the Gymnosperms generally). The Cone (syn-
carpium, tfuv, together) of the Magnolia tribe is a mass of con-
fluent, closed pericarps on a lengthened torus (Cucumber Tree).


1W, Strobile of Finns. 195, The Tip: Csyconus). 196, Sorosis of Mulberry. 197, Hip of Kosa, aclienin
nearly enclosed in the leathery calyx tube.

170. The Fig (syconus) is an aggregate fruit, consisting of
numerous seed-like pericarps enclosed within a hollow, fleshy
receptacle, where the flowers were attached.

171. Other confluent fruits (Sorosis) consist of the entire in-
florescence developed into a mass of united pericarps, as in the
Mulberry, Osage-orange, Pineapple.

Eemew. 150. Name the first division of fruits. Free fruits, how subdivided ? Name
the five indehiscent, 1-seeded, 1-coated fruits. How do we distinguish them? Name the
three indehiscent, 1-seeded, several-coated fruits. Difference between drupe and tryma ?
Etserio? Name the four indehiscent, several-seeded fruits. How does pome differ
from the others ? Are the dehiscent pericarps fleshy or dry ? Distinguish the Pyxis.
Name three simple fruits which open by valves. Distinguish them. Name four com-
pound, opening fruits. What is the fruit of Mustard, etc. ? Find all the figures. The
subdivision of confluent fruit?, etc.., etc.




172. The seod is the perfected ovule, having an embryo
formed within, which is the rudiment of a new plant similar in
all respects to the original. The seed consists of a nucleus or
kernel invested with the integuments or coverings. The outer
covering is the testa, the inner the tegmeti, as in the ovule. The
latter is thin and delicate, often indistinguishable from the testa.

173. The testa is either membranous (papery), coriaceous
(leathery), crustaceous (horny), bony, woody, or fleshy. Its
surface is generally smooth, sometimes beautifully polished, as
m Columbine, Indian-shot (Canna), and often highly colored,
as in the Bean ; or it may be dull

and rough. It is sometimes winged,
as in Catalpa, and sometimes clothed
with long hairs, as in Silk-grass
(Asclepias). Such a vesture is called
the Coma. Cotton is the coma of
the Cotton-seed.


174. The coma must not be confounded with
the pappus (' 104), which is a modification of the
calyx, appended to the pericarp, and not to the
teed, as in the achenia of the Thistle, Dandelion,
and other Composite. Its intention in the econ-
omy of the plant cannot be mistaken ; serving
like the pappus to secure the dispersion of the
seed, while incidentally as it were, in the case of
the Cotton-seed, it furnishes clothing and em-
ployment to a large portion of the human race.

175. The aril is an occasional appendage, par-
tially or wholly investing the seed. It originates

after fertilization, at or near the hilum, where the OI U()Uon -
seed is attached to its stalk (funiculus). Fine ex-
amples are seen in the gashed covering of the Nutmeg, called mace, and in the scarlet
coat of the seed of Staff-tree. In the seed of Polygala, etr., it is but a small scale, entire
or 2-cleft, called caruncle.

170. The position of the seed in the pericarp is, like that of the ovule, (.reel, ascending.
jwndulouSi etc. ( 149). Likewise in respect to its inversions, it is orthbtropous, andtro-
pous, ampJiUropous, and campylotropous ( 141), terms already defined. The anatroppna
ie by far the most common condition.

198. Aril of Nutmeg dunce). 199, Seed of
ittalpa. 200, Seed of Willow. 201, Seed



177. The hilum is the scar or mark left in the testa of the
seed by its separation from the funiculus. It is commonly called
the eye, as in the Bean. In orthotropous and campylotropous
seeds, the hilum corresponds with the chalaza ( 140). In other
conditions it does not; and the raphe ( 141) extends between
the two points, as in the ovules. The foramen of the ovule is
closed up in the seed, leaving a slight mark the micropyle.

203 204




202, Seed of Water Lily (Nymphsea), enlarged section; alb., albumen; n, the embryo contained in tl.i
embryo-sac; ,, tegmen; p, testa; r, raphe; ar, aril; m, orifice; /, funiculus. 203, Seed of Bean. 204,
Same, one cotyledon with the leafy embryo. 205, Seed of Apple. 206, One cotyledon showing the
raphe and embryo. 207, Fruit of Mirabilis: embryo coiled into a ring. 208, Onion; embryo coiled.
209, Convolvulus; leafy embryo folded. 210, Embryo of Cuscuta. 211, Typha. 212, Ranunculus.
213, Hop.

178. The seed-kernel may consist of two parts, the embryo
and albumen, or of the embryo only. In the former case the
seeds are albuminous in the latter, exalbuminous a distinction
of great importance in systematic botany.

179. The albumen is a starchy or farinaceous substance
accompanying the embryo and serving as its first nourishment
in germination. Its qualities are wholesome and nutritious,
even in poisonous plants. Its quantity, when compared with
the embryo, varies in every possible degree ; being excessive
(Ranunculaceae), or about equal (Violacea3), or scanty (Convol
vulacere), or none at all (LeguminosaB). In texture it is mealy
in Wheat, mucilaginous in Mallows, oily in Ricirms, horny in
Coffee, ruminated in Nutmeg and Pawpaw, ivory-like in the
Ivory-palm (Phytelephas), fibrous in Cocoanut, where it is also
hollow, enclosing the milk.

180. The embryo is an organized body, the rudiment of
the future plant, consisting of root (radicle), stem-bud (plumule].



and leaves (cotyledons). But these parts are sometimes quite
undistinguishable until germination, as in the Orchis tribe.
The Radicle is the descending part of the embryo, always point-
ing toward the micropyle, the true vertex of the seed. The
Plumule is the germ of the ascending axis, the terminal bud,
located between or at the base of the Cotyledons. These are
the seed-lobes, the bulky farinaceous part of the embryo, des-
tined to become the first or seminal leaves of the young plant.
The nutritive matter deposited in the seed for the early suste-
nance of the germinating embryo, is found more abundant in the
cotyledons in proportion as there is less of it in the albumen
often wholly in the albumen (Wheat), again all absorbed in the
bulky cotyledons (Squash).

181. The number of the cotyledons is variable; and upon this
circumstance is founded the most important subdivision of the
Flowering Plants. THE MONOCOTYLEDONS are plants bearing
seeds with one cotyledon ; or if two are present, one is minute
or abortive. Such plants are also called ENDOGENS, because
their stems grow by internal accretions ( 421). Such are the
Grasses, the Palms and Lilies, whose leaves are mostly con-
structed with parallel veins.


214, Dicotyledonous (Bean). 215. Mnnocntyledonous (Wheat). 216, Polycotylednntus (Pine). 217,
Acotyledonous (.zoospore of one of the Cmifervse). (r, r, r, radicle; ;>, p, p, plumule; c, c, c, cotyledon;
a, albumen.)

182. THE DICOTYLEDONS are plants bearing seeds with two
cotyledons. These are also called EXOGENS, because their stems
grow by external accretions ; including the Bean tribe, Melon
tribe, all our forest trees, etc. These are also distinguished at a


glance by the structure of their leaves, which are ntt-veiiied
( 280). More than two cotyledons are found in the seeds of
Pine and Fir ; while the Dodder is almost the only known exam-
ple of an embryo with no cotyledon.

183. The position of the embryo, whether with or without
albumen, is singularly varied and interesting to study. It may
be straight, as in Cat-tail and Violet, or curved in various de-
grees (Moonseed and Pink), or coiled (Hop), or rolled (Spice-
bush), or bent angularly (Buckwheat), or folded (Cruciferse).
In the last case two modes are to be specially noticed. 1, In-
cumbent, when the cotyledons fold over so as to bring the back
of one against the radicle (Shepherd's Purse) ; 2, accumbent,
when the edges touch the radicle (Arabis).

184. A few plants, as the Onion, Orange, and Coniferae, occasionally have two or even
several embryos in a seed ; while all the Cryptogamia or flowerless plants have DO em-
bryo at all, nor even seeds, but are reproduced from spores bodies analogous to the pol-
len-grains of flowering plants (217).

185. Vitality of the seed. After the embryo has reached
its wonted growth in the ripened seed, it becomes suddenly inac-
tive and torpid, yet still alive. In this condition it is, in fact, a
living plant, safely packed and sealed up for transportation.
This suspended vitality of the seed may endure for years, or
even, in some species, for ages. The seeds of Maize and Rye
have been known to grow when 30 to 40 years old ; Kidney-
beans when 100; the Raspberry after 1700 years (Lindley).
Seeds of Mountain Potentilla (P. tridentata) were known to us
to germinate after a slumber of 60 years. On the other hand,
the seeds of some species are bhort-lived, retaining vitality hardly
a year (Coffee, Magnolia).

186. Tlie dispersion of seeds over wide, and often to distant regions, is effected
by special agencies, in which the highest Intelligence and Wisdom are clearly seen. Some
seeds made buoyant by means of the coma or pappus, already mentioned, are wafted afar
by the winds, beyond rivers, lakes, and seas : as the Thistle and Dandelion. Other seeds i
have wings for the same purpose. Others are provided with hooks or barbs, by which
they lay hold of men and animal;?, and are thus, by unwilling agents, scattered far and
wide (Burr-seed, Tick-seed). Again: some seeds, destitute of all such appendages, are
thrown to a distance by the sudden coiling of the elastic carpels (Touch-me-not). The
Squirting-cucumber becomes distended with water by absorption, and at length, when
ripe, bursts an aperture at the base by separating from the stem, and projects the mingled
seeds and water with amazing force.

187. Rivers, streams, and ocean currents, are agents for transporting seeds from coun-
try to country. Thus the Oucoa, and the Caehew-nut, and the seeds of Mahogany, have



been known to perfoim long voyages without injury to their vitality. Squirrels laying
up their winter stores in the earth ; birds migrating from clime to clime and from island
to island, in like manner conspire to effect the same important end.

Eeview. 172. What is the seed? Its two coverings. 173. The texture of the testa.
Its appendages. What is cotton? 174. Distinguish coma from pappus. 175. What is
the aril ? 176. Positions of the seed in the cell. When is a seed anatropous ? Orth6tro-
pous? etc. 177. Define hilum. When does a raphe exist ? What ia the micropyle? 178.
Constituents of an albuminous seed Exalbmninous. 179. Varying proportions of albu-
men. Various texture. 180. Distinguish the three parts of the embryo. Where is rhe
food for the embryo ? 181. Distinguish the Monocotyledonous Plants. 182. The Dicoty-
ledonous. 183. Position of the embryo in the seed of Violet? Of Pink? Hop? Shep-
herd's Purse ? Arabia ? 185. Vitality of the seed. 186. Special arrangements for their



188. The recommencement of growth in the seed is called
germination. It is the awakening of the embryo from its tor-
por, and the beginning of development in its parts already
formed, so as to become a plant like its parent.




Germintttinn of the Beec7niut.2lR, Cross-section, showing the folded cotyledons. 219, The radicle
only. 220. The ascending axis, above c, appears. 221, The cotyledons expand into the primordial
leaves. 222, The first true leaves.

189. All the stages of this interesting process may be conveniently observed, at. any
season, by an experiment. Let a few seeds, as of flax, cotton, wheat, pea, bs enveloped
in a lock of cotton resting upon water in a bulb-glass, and kept constantly at a proper tern
Or, in Spring, the garden-soil will give us examples of all kinds everywhere.



J 90. That the seed may begin to grow, or germinate, it is first
planted ; or, at least, placed in contact with warm, moist soil.
Concerning the proper depth of the planted seed, agriculturists
are not agreed ; but nature seems to indicate that no covering
is needed beyond what will secure the requisite moisture and
shade. Thus situated, the integuments gradually absorb water,
soften, and expand. The insoluble, starchy matter deposited in
the cotyledons, or in the albumen, or in both, undergoes a cer-
tain chemical change, becoming sweet
and soluble, capable of affording nour-
ishment to the embryo now beginning:


to dilate and develop its parts. First
(in the winged seed of the Maple,
scattered everywhere) the radicle is
seen protruding from the micropyle,
or the bursting coverings. A section
of this seed would now show the fold-
ed embryo, impatient of confinement

191. Soon after, the radicle has ex-
tended ; and, pale in color, has hidden
itself in the dark damp earth. Now
the cotyledons, unfolding and grad-
ually freed from the seed-coats, display
themselves at length as a pair of green
leaves. Lastly the plumule appears
in open air, a green bud, already show-
ing a lengthening base, its first inter-
node, and soon a pair of regular leaves, lobed as all Maple-leaves.
The embryo is now an embryo no longer, but a growing plant
descending by its lower axis, ascending and expanding by its

1 92. With equal advantage we may watch the germination of
the Beech, represented in the figures above ; or of the Oak, as
displayed in figures 1, 2, 3, 4 ; or the Pea, or Squash, and other
Dicotyledons ; and the chief difference observed among them
will be in the disposal of the cotyledons. In general, these arise
with the ascending axis, as in Maple and Bean, and act as the

Germination of Wheat. o, the grai.1,
containing the cotyledon; r, plumule;
r, radicle; s, rootlets (adventitious).


first pair of leaves. But sometimes when they are very thick, as
in Pea, Buckeye, and Oak, they never escape the seed-coats, but
remain and perish at the collum ( 199), neither ascending nor


Germination of the Maple. 225, Samara; section showing the folded cotyledons at c. 22&-230, l*ro>

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