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one of the earliest flowers of our gardens, not unfrequently blossoming in the neighbourhood of a snow bank. It has a bulbous root, long and narrow leaves, a spatha kind of calyx, and six petals. Besides the Crocus vernus or spring crocus, which often appears even in our own climate as early as March, there is, of this genus a very distinct species, the Crocus officinalis, or the true saffron, which appears among the late flowers of autumn. The following beautiful lines, respecting these flowers, are from the pen of the interesting Henry Kirke White, whose untimely death, in the spring time of his existence, has been deeply regretted, but his early and fervent piety, marked him as a fit inhabitant fór a purer sphere; a christian, and philosopher, he could see an invisible hand directing the operations of nature.
“Say, what impels amid surrounding snow
Or to each lingering bloom, enjoins delay.” The Iris, or Fleur-de-lis, (pronounced by a corruption of the French, Flower de luce,) is the national flower of France, as the Rose is of England. You will find on attentive examina. tion that this is a very curious flower. It has no proper calyx, but a spatha; its corolla consists of six parts, alternately reflected, or bent back ; the pistil has three stigmas, which appear at first view like petals. The Iris is so named from Iris, the rainbow, on account of the various colours which it reflects, varying from different shades of purple, into blue, orange, yellow, and white. We have several native species of Iris, one of which, the common Blue flag, is found in wet places. The flowers are purple, streaked with yellow; this is sometimes called Poison flag. The Crocus and Iris are found in the natural family of Jussieu called Irideæ; this family is in the class of monocotyledons, having stamens around the germ, or perigynous. Linnæus calls the same plants, Ensatæ from the Latin word ensis, a sword, on account of the shape of their leaves, being long, narrow and pointed.
In what family is the Iris found ?
Order Digynia. The Grasses. The 2d Order of the third class contains the family of the grasses (Gramina); they are distinguished by a strait, hollow, and jointed stem, or culm; the long and linear leaves are pla. ced at each joint of the stalk in alternate order, enclosing it like a sheath. The flowers of the grasses are found in what is called the ear, or head, and consist of two green husks, called a glume ; within this glume calyx is the blossom, con. sisting of a husk of two valves. These husks constitute the chaff, which is separated from the seed by an operation called threshing.
These little flowers, which are also furnished with a nectary, are green, like the rest of the plant, and you will need a microscope to view them accurately ; they are best observed in a mature stage of the plant, when their husks, expanded, discover their three filaments, containing each a large double anther; their two pistils have a kind of reflected, feathered stig
They have no seed vessel ; each seed is contained within the husks, which gradually open ; and unless the seed is gathered in season, it falls to the ground. This facility for the distribution of the seed is one cause of the very general diffusion of grasses.
The roots of grasses are fibrous, and increase in proportion as the leaves are trodden down, or consumed; and the stalks which support the flower are seldom eaten by cattle, so that the seeds are suffered to ripen. Some grasses which grow on very high mountains where the heat is not sufficient to ripen the seed, are propagated by suckers or shoots, which rise from the root, spread along the ground, and then take root them. selves; grasses of this kind are called stoloniferous, which
Explain Fig. 104—What family is found in the order Digyaia ?—Roots of
means bearing shoots. Some others are propagated in a man. ner not less wonderful; for the seeds begin to grow while in the flower itself, and new plants are there formed, with little leaves and roots; they then fall to the ground, where they take root., Such grasses are called viviparous, which signifies producing their offspring alive, either by bulbs instead of seeds, or by seeds germinating on the plant. The seeds of the grasses have but one lobe, or are not naturally divided into parts, like the apple seed and the bean ; therefore these are said to have but one cotyledon.
The stems of gramineous plants, like those of all the mono. cotyledons, are of that kind which grow internally, or from the centre outward, and are therefore called endogenous.
With regard to the duration of the grass-like plants, some are annual ; as, wheat, rye, and oats, whose roots die after the grain or seed is matured. The meadow grasses are perennial ; their herbage dying in autumn, and the roots sending out new leaves in the spring. The family of grasses is one of the most numerous, the most important and the most natural of all the vegetable tribes; the plants which compose it, seem, at the first glance, to be so similar that it would appear impossible to sepa. rate them into species, much less into genera; but scientific research, and close observation present us with differences, suffi. cient to form a basis, for the establishment of a great number of genera.
The essential character of the oat (Avena), consists in the jointed, twisted awn or beard which grows from the back of the blossom; the oat is also remarkable for its graceful pannicle, or the manner in which its flowers grow upon their stalks.
The rye (Secale), has two flowers within the same husk. The wheat (Triticum), has three flowers within the same husk; the interior valve of the corolla of the wheat is usually beard. ed. The filaments in the rye and wheat are exsert, that is, they. hang out beyond the corolla ; from which circumstance, these grains are more exposed to injury from heavy rains than those whose filaments are shorter.
Perhaps, in the whole of the vegetable kingdom, although there are many plants of much greater brilliancy of appearance, there are none which are so important to man as the grass family. Linnæus, who was distinguished for the liveliness of his fancy, no less than the clearness of his reasoning powers, seemed to delight in tracing analogies between plants and mankind; establishing among the former a kind of aristocracy; he called grasses the plebeians of the vegetable kingdom. To them, indeed, belong neither brilliancy of appear.
Comparison of Linnæus.
ance nor delicacy of constitution; numerous, humble and rustic, and and at the same time, giving to man and beast the sus. tenance necessary to preserve life, the grasses may well be compared to the unassuming farmer and mechanic, to whom society is indebted far more than to the statesman and orator for its existence and prosperity.
The grasses are supposed to include nearly one sixth part of the whole vegetable world ; they cover the earth as with a green carpet, and furnish food for man and beast. Some of the grasses most valuable as furnishing food for cattle, are herds-grass (Phleum pratense); and meadow grass (Poa); orchard grass (dactylis); and oats.
Those which are used in various ways as food for man, are wheat, rye, barley, and indian corn; this latter, botanically called Zea mays, although of the natural family of the grasses, having a culm-like stalk and other distinguishing characteristics of grass-like plants, is placed in the class Monccia, because the stamens and pistils are sepa. rated in different flowers, growing from the same root.
The styles, long, slender, and exserted, form what is called the silk : they are thus favourably situated for receiving the fertilizing pollen which is showered down from the staminate flowers.
The fruit of corn, wheat, rye, &c. is called grain. Grain, then, consists of the seed with its pericarp; these are not easily distinguished from each other till the grain is ground in. to flour; the pericarp separating from the seed then forms what is called the bran; and the seed, the flour or meal.
The sugar cane (SACCHARUM officinarum), is of the grass family; it is supposed to have been brought from the South of Europe to the West Indies. The stem or culm, which sometimes
grows to the height of twenty feet, affords the juice from which the sugar is made.
The Bamboo (Arundo bambos), of the East Indies, a spe. cies of reed which is said to attain, in some situations, the height of sixty feet, is also of this class.
The Sedge (Carex), is a gramineous plant, but it bears staminate and pistillate flowers, and is therefore placed in the class Monæcia. The carexes* constitute a very numerous family of plants.
* The plural of carex, according to the Latin termination, is carices.
Grasses used as food for cattle and man—Zea mays--Sugar cane- -Bamboo -Carex.
Fig. 105 repre. sents two magnified flowers of the orchard grass (Dactylis glo. merata*); at a, is a calyx,t composed of two valves; these are compressed, keeled, acute; one valve is shorter than the parts
of the flowers, the other longer ; this calyx is common to the two flowers: shews the valves or parts of the corollas; they are oblong and acute : c represents the stamens, which are three in each flower; the filaments are of the length of the corolla ; the anthers are two forked or bifid : d is the pistil, having an egg-shaped germ, and two spreading and feathery styles : at e, is the seed, not hav. ing any proper pericarp, but enclosed by the two scales of the corolla ; it is single and naked.
Glomerata signifies a cluster, alluding to the crowded panicles of flowers. + The parts of the calyx, and also of the corolla, are called glumes ; they are all much alike in appearance, being merely a set of sheaths, for the purpose of protecting the stamens; they are not distinguished by any difference in colour from the leaves or stem. The anthers, which are usually yellow, are the only part of the blossom of the grasses which is coloured. | Resembling the keel of a boat.