Midrib Sentence Examples

The midrib has a strong band of stereom above and below.

The leaf consists of a central midrib, several cells thick, and two wings, one cell thick.

The leaf has a broadly sheathing base succeeded by a short stalk bearing the pitcher, which represents a much enlarged midrib with a winglike lamina.

The centre of the leaf is often occupied by a midrib consisting of several layers of cells.

In it no fruit is produced, and the pistil consists merely of sessile leaves, the limb of each being green and folded, with a narrow prolongation upwards, as if from the midrib, and ending in a thickened portion.

Or the thallus may have a leaf-like form, the branches from the central threads which form the midrib growing out mainly in one plane and forming a lamina, extended right and left of the midrib.

In three generaBlyttia, Symphyogyna and Hymenophytum there are one or more strands or bundles consisting of long thickwalled fibre-like (prosenchymatous) cells, pointed at the ends and running longitudinally through the thick midrib.

In the more highly developed series, the mosses, this last division of labor takes the form of the differentiation of special assimilative organs, the leaves, commonly with a midrib containing elongated cells for the ready removal of the products of assimilation; and in the typical forms with a localized absorptive region, a well-developed hydrom in the axis of the plant, as well as similar hydrom strands in the leaf-midribs, are constantly met with.

The stereom of the moss is found mainly in the outer cortex of the stem and in the midrib of the leaf.

In the larger veins of the leaf especially in the midrib, in the petiole, and in the young stem, a1 extremely frequent type of mechanical tissue is collenchyma.

The leaves of the foxglove, gathered from wild plants when about two-thirds of their flowers are expanded, deprived usually of the petiole and the thicker part of the midrib, and dried, constitute the drug digitalis or digitalis folia of the Pharmacopoeia.

A leaf with only a single midrib is said to be unicostate and the venation is described as pinnate or feather-veined.

The midrib, or petiole, has thus the appearance of a branch with FIG.

Similar turgescence changes, taking place with similar rapidity in the midrib of the leaf of Dionaea, explainthe closing of the lobes upon their hinge.

When uniformly damped, the leaves are separately opened out and smoothed, the midrib, if not already removed, is torn out, except when " bird'seye " cut is to be made, in which mixture the midrib gives the peculiar " bird's-eye " appearance.

The effect of the light falling upon them is to produce along the midrib of each a number of short white streaks of light, which contrast most strongly with the shadows cast by the leaves themselves, and with the general twilight gloom of the forest.

In this way two marked forms of leaf are produced - (I) Simple form, in which the segmentation, however deeply it extends into the lamina, does not separate portions of the lamina which become articulated with the midrib or petiole; and (2) Compound form, where portions of the lamina are separated as detached leaflets, which become articulated with the midrib or petiole.

Besides the midrib there are two intra-marginal ribs which converge to the apex.

Compound leaves are those in which the divisions extend to the midrib or petiole, and the sepa rated portions become each arti culated with it, and receive the name of leaflets.

Some petioles are long, slender and sensitive to contact, and function as tendrils by means of which the plant climbs; as in the l,' nasturtiums (Tropaeolum), clematis and c in others; and in compound leaves the midrib and some of the leaflets may similarly be transformed into tendrils, as in the pea and vetch.

A very finely made copper dagger (60) with deep midrib is dated to between 55 and 60 S.D.

In Iridaea the thallus is an entire lamina; in Callophyllis a lobed lamina; in Delesseria it is provided with midrib and veins, simulating the appearance of a leaf of the higher plants; in Constantinea the axis remains cylindrical, and the lateral branches assume the form of leaves.

The venation is strictly parallel, the midrib usually strong, and the other ribs more slender.

In dry-country grasses the blades are often folded on the midrib, or rolled up. The rolling is effected by bands of large wedge-shaped cells - motor-cells - between the nerves, the loss of turgescence by which, as the air dries, causes the blade to curl towards the face on which they occur.

The flowering glume has generally a more or less boat-shaped form, is of firm consistence, and possesses a well-marked central midrib and frequently several lateral ones.

The Cyas type of frond, except as regards the presence of a midrib in each pinna, characterizes the cycads generally, except Bowenia and Stangeria.

The sori are borne on the under surface of the pinnae, usually in a single row on either side of the midrib, but in Kaulfussia dotted over the expanded lamina.

In 1843 a German bee-keeper, Krechner by name, conceived the idea of first dipping fine linen into molten wax, then pressing the sheets so made between rollers, and thus forming a waxen midrib on which the bees would build their combs.

These sheets were readily accepted by the bees, and afterwards plates cast from metal were employed, with so good a result as to give to the bees as perfect a midrib as that of natural comb with the deep cell walls cut away.

Weed, a skilful American machinist, who, after some years of strenuous effort, succeeded in devising and perfecting special rollers and dies, by the use of which foundation was produced with a midrib so thin as to compare favourably with natural comb built by the bees.

In marginal placentation the part of the carpel bearing the placenta is the inner or ventral suture, corresponding to the margin of the folded carpellary leaf, while the outer or dorsal suture corresponds to the midrib of the carpellary leaf.

In the Lower Carboniferous of Scotland Mr Kidston has found several specimens of a large dichotomous thallus, with a very distinct midrib; the specimens, referred to the provisional genus Thallites, much resemble the larger thalloid Liverworts.

Associated with Glossopteris occurs another fern, Gangamopteris, usually recognized by the absence of a well marked midrib, though this character does not always afford a satisfactory distinguishing feature.

Professor Nathorst, as the result of a more recent examination of Heer's specimen, found that the segments of the frond are characterized by the presence of two parallel veins instead of a single midrib, with a row of stomata between them; for this type of Cycadean leaf he proposed the generic name Pseudocycas.

These support multitudes of large and glossy dark green narrow leaves which are silver gray beneath and have a yellow midrib.

Large fleshy leaves with a prominent midrib, tall woody stem, strings of green flowers turning to brown seedpods.

A study of the development of the pitcher, especially in the young pitchers of seedling plants, shows that the inflated portion is a development of the midrib of the leaf, while the wings, which are especially well represented in the terrestrial type of pitcher, represent the upper portion of the leaf-blade which has become separated from the lower portion by the tendril; the lid is regarded as representing two leaflets which have become fused.

The midrib bears above a series of closely set, vertical, longitudinally-running plates of green assimilative cells over which the wings close in dry air so as to protect the assimilative and transpiring plates from excessive evaporation of water.

America, its stout leathery fronds once cut to the midrib being 4 or 5 feet long, and produced on stout red stalks from a prostrate fleshy stem or trunk.

The midrib is prolonged into a stout wiry tendril, which holds on firmly to anything it once clasps.

The leaves are about 2 inches long, the margins spiny-toothed, the texture leathery, and the midrib extending beyond the blade, branching and forming a strong twining tendril.

The leaves average 1 1/2 inches to 2 inches in length, and are cut half-way to the midrib into several sharply-pointed lobes.

They are shrubby plants climbing over surrounding vegetation by means of tendrillike prolongations of the midrib of the leaf beyond the leaf-tip.