In the early days the indusium is of a lead colour, but as the sporangia ripen underneath the brown colouring shows through the thin covering.
As a rule the bursting of the sporangia takes place during dry weather.
With a magnifying glass it is plainly seen that the margin of the cup-shaped receptacle into which the sporangia are gathered has not the toothed border to be found in the case of the Tunbridge Filmy Fern.
The stem does not start at once to produce leaves bearing thesporangia or spore cases.
During the early days the cluster of sporangia is covered with very distinct indusia, but as the capsules ripen, these disappear.
At first they are covered with scale-like indusia, but as the sporangia ripen the protecting shield is thrown aside.
In distinguishing the different families, the manner in which the collections of spore cases, known as sori, occur, as well as the features which the individual sporangia present, are important guides.
There is no proper indusium, but the leaf margin curls over and protects the sporangia to some extent.
In the case of Trichomanes the axis on which the sporangia are inserted often projects beyond the cup in which they are contained.
When the sporangia are mature the back of the Bracken frond, with its outline of bright brown, is very pretty.
These sporangia are seen to grow out from the sides of a mass of special tissue, known as the placenta, from which the indusium really arises.
It is along the margins of the lobes of the leaf that the sporangia are produced.
After removing the kidney-shaped cover (indusium) we shall be able to see the spore cases or sporangia quite clearly.
In some cases the sporangia are borne on distinct leaves, as in the case of the Hard Fern, or on special parts of the leaves, in the manner to be seen in the Royal Fern.
So large is the family that it has been divided into a number of sub-families; the members of these are chiefly characterized by the position of the sorus, the cluster of sporangia on the back of the frond.
The sporangia are borne on curious scales which are supported by stalks placed in the centre.
Sporangia closely packed and grown together; the walls a thin, violaceous membrane, rugulose, with a thin, closely adherent layer of granules of lime.
Sporangia cylindric, bent or flexuous and more or less inclined, growing close together on a conspicuous purplish-brown hypothallus.
Sporangia small, subcylindric, tapering and obtuse at the apex, tapering gradually downward, growing close together on a thin brown hypothallus.
Sporangia simple and subglobose, or plasmodiocarp, rarely combined into an æthalium.
Sporangia varying from globose to pyriform or turbinate, supported on a more or less elongated stipe.
Sporangia obovoid to oblong, sessile and closely crowded on a well-developed common hypothallus.
The sporangiaare dull brownish to the naked eye, but when magnified the green, purple, and blue metallic tints of the wall become apparent.
The fertile shoots terminate in cones, on the modified leaves of which the sporangia are produced.
For Apospory and Apogamy, see Lang "On Apogamy and the Development of Sporangiaupon Fern Prothalli," Phil.
The sporangia or cases which contained the microscopic spores or seeds were arranged around a central axis in a somewhat similar manner to that in which maize is found.
Pellàea Sporangia borne on the upper part of the free veins inside the margins, in dot-like masses, but may run together, as in the continuous fruiting line of the bracken.
Sporangia surrounded by vertical, elastic rings bursting transversely and scattering the spores.
Sporangia borne on an elevated, globular receptacle in a membranous, cup-shaped indusium which is open at the top.
Corresponding with these five families, the sporangia or spore cases of ferns have five quite distinct forms on which the families are founded.
Sporangia large, globular, short-stalked, borne on the margin of the divisions and opening into two valves by a longitudinal slit.
Sporangia borne in a continuous line along the lower margin of the ultimate divisions whose reflexed edges form the indusium.
In Ophioglóssum the leaf or sterile segment is entire, the veins reticulated and the sporangia in a simple spike.
A loose compound cluster of flowers or sporangia with irregular stems.
Sporangia clustered around the slender bristle, which is the prolongation of a vein, and surrounded by a vase-like, slightly two-lipped involucre.
Open sporangia close again and are flattened or of a lenticular form.
Here he spent much labour in considering the view, originally due to Hedwig, that the ramenta were male organs by the effect of which the sporangia developed.
Griffith saw that if this was so, since the sporangia are initiated very early, the only time to search for the male organs was in the very young stage of the leaf.
It seems to me very probable that these isolated sporangiaare identical with the hyaline coagula so accurately described by Frerichs, who has observed them in the blood of patients dying of intermittent fevers.
With a linear magnitude of 480, the sporangia have a transverse diameter of one to five millimeters, or a little more in the larger specimens.
The sporangia are never spherical, but always flat.
The sporangia were very red and beautiful, but they showed no double cell wall.
It is not rare, however, to see the individual sporangia perfectly isolated and disembarrassed of their filament of mycelium floating in the water.
Now, it is these sporangia of the Lepidodendroid plant Flemingites which were identified by Mr. Carruthers with the free sporangiadescribed by Professor Morris, which are the same as the large sacs of which I have spoken.
There are four sporangia borne on the under-surface of the peltate leaves.
Microspores from sporangia of the upper part of the cone of Triplosporites Brownii, Brongn.
Carruthers has recently detected the separate sporangia of Ferns full of spores in calcareous nodules in coal (Plate I.
These sporangia have been found connected with the cone-like fructification called Flemingites, and resembling Lycopodium (woodcut 44, Fig.
The arrangement of the different parts comprising it is precisely similar to what occurs in Triplosporites; but the sporangia are filled with the minute triple spores throughout the whole cone (woodcut 44, 6 and 8).
Goldenberg has figured the fructification, which consists of small sporangia like those of Flemingites, borne on the basis of but slightly modified leaves.
The small round sporangia of Sigillaria are borne in a single patch on the somewhat enlarged bases of some of the leaves.
Better bed of Bradford, are composed almost entirely of these sporangia imbedded in their shed microspores, as has been recently shown by Huxley.
Transverse section of a Lepidostrobus, the fructification of Lepidodendron, showing scales andsporangia (Hooker).
Portion of a frond separated to show the linear sori or clusters of sporangia (spore-cases).
These sporangia occur in coal from different localities in England and Scotland.
The genus Sigillaria, as we have already said, has, according to the observation of Hooker, small sporangia exactly agreeing in size and form with those of Flemingites.
The large sporangia have a double wall, the outer composed of a compact layer of oblong cells placed endwise, or with the long diameter perpendicular to the surface; the inner is a delicate cellular membrane.
In habit the sporangia are widely scattered, much more than is common in the species of this genus.
Sporangia to which the peridium still adheres, although in 3 c in shreds.
Among various gatherings studied he found a black variety, a melanistic phase, so to say, and was able to follow the evolution of the sporangia from the yellow plasmodium.
Sporangia furnished with rigid, unpolished stipes, blending above with the substance of the thick unpolished walls; the operculum thin, delicate, membranaceous.
The fronds are very delicate and often translucent, and thesporangia are borne on threadlike receptacles rising from the middle of cup-shaped marginal involucres.
The sporangia of ferns are believed to be of the nature of trichomes.
On the lower side of each are borne two sporangia (pollen sacs) (C, sp.
This species sometimes bears clusters of very smallsporangia attached to the middle of the ordinary sporangial filament (Fig.
A section across the anther shows it to be composed of four sporangia or pollen sacs attached to a common central axis ("connective") (Fig.
In Botrychium the leaves are more or less deeply divided, and the sporangia distinct (Fig.
The leaflets bearing thesporangia are more or less contracted and covered completely with the sporangia, sometimes all the leaflets of the spore-bearing leaf being thus changed, sometimes only a few of them, as in the species figured.
C, a scale from a male flower, showing the two sporangia (sp.
Comparing this with the sporangia of the pteridophytes, the first difference that strikes us is the presence of an outer coat or integument (in.
J, the same, with the incurved edges of the leaflet partially raised so as to show the masses of sporangia beneath, × 2.
In the early stages of its growth the plant multiplies by zoöspores, produced in great numbers in sporangia at the ends of the branches.
In these the sporangia are large and the ring (r) rudimentary.
In Ophioglossum the sterile division of the leaf is usually smooth and undivided, and the spore-bearing division forms a sort of spike, and the sporangia are much less distinct.
On the other hand, propagation organs, differing from those of the sporangia and their products, belong to Mucor mucedo, which may be termed conidia.
Mr. Berkeley succeeded in developing up to a certain point the fungus of the Madura Foot, but though perfect sporangia were produced, the further development was masked by the outgrowth of other species.
In some species thesporangia contain two, in others four, in others eight, and in others numerous sporidia.
They here germinate and produce a mycelium which exactly resembles that of the Mucor mucedo, and, above all, they produce in profusion the typical sporangia of the same on its bearers.
The method of diffusion agrees much with that of the Mucedines, the walls of the sporangia being usually so thin and delicate as to be easily ruptured.
On the other hand the sporangia of these plants were usually borne on special fertile fronds, a mark of rather high differentiation.
The classification of the Mucorini depends on the prevalence and characters of the conidia, and of the sporangia and zygospores--e.
Mycelium well developed; sexual reproduction by zygospores; asexual reproduction by sporangia and conidia.
In the formation of sporangia two cells fuse together by means of outgrowths, in a manner very similar to that of Spirogyra; sometimes, however, the wall between two cells merely breaks down.
Sexual reproduction as above, asexual bysporangia or conidia or both: Mucoraceae.
In addition tosporangia and the conidial spores referred to, some Mucorini show a peculiar mode of vegetative reproduction by means of gemmae or chlamydospores--i.
A remarkable feature of the plant is that there were also round those sporangia which bore the numerous small spores (corresponding to pollen grains) enclosing integument-like flaps similar to those shown in fig.
The fructifications were presumably fern sporangia of normal but rather massive type.
Its sporangia were borne on stalks similar to those of Sphenophyllum, but each stalk had two sporangia attached to it.
Other sporangia with small spores were developed which gave rise to the male organs.
These plants help in elucidating the nature of the stalked sporangia of Sphenophyllum, for they seem to indicate a direct comparison between them and the sporophylls of the Equisetales.
Other cones had sporangia similar in size and shape, but which produced spores of two kinds, large ones resulting from the ripening of only two or three tetrads in the lower sporangia, and numerous small ones in the sporangia above.
Some fossils have such sporangia with eight spores, or some other small number; living Selaginellas have four.
The pollen grains seem to have been produced in sacs very like fern sporangia developed on normal foliage leaves, each grain entered the cavity pc in the seed (see fig.
Cases of likeness are seen in the sporangia of ferns, some of which appear to have been practically identical with those now living.
From the later Mesozoic we have only material in the form of impressions, from which it is impossible to draw accurate conclusions unless the specimens have sporangia attached to them, and this is not often the case.
In the actual sections of Sphenophyllum cones the numerous sporangia seem massed together in confusion, but usually some are cut so as to show the attachment of the stalk, as in fig.
The sporangia have twenty-six or twenty-eight articulations of the ring.
The sporangia have a ring of from fifteen to twenty articulations.
The articulations of thesporangia are said by Fee to be twenty-eight to thirty-two, and more numerous than in any other fern.
The tips of the veinlets extend into these involucres, and bear the sporangiaon the under or inner surface.
The sporangia are comparatively scanty, and are fully covered by the involucre.
The sporangia have a ring of about twenty articulations: Fee says there are vittate or knotted hairs growing among them.
The sporangia are quite small and numerous, not attached by a funiculus to the peridium, enveloped in mucus.
The sporangia are blackish, frequently somewhat pale, even; covering rather thick, sprinkled with a grayish meal.
The sporangia are subrotund or discoidal in form, dark brown, smooth, shining.
Sporangia plane, umbilicate, attached to the wall by an elastic cord.
The sporangia are cylindrical and pointed at the apex, peridia fugacious, exposing the beautiful net-work of the capillitium.
These patches of sporangia are called sori or fruit-dots.
Fertile fronds unrolling at maturity, allowing the spores to escape, and remaining long after the sterile fronds have perished; sporangia stalked, ringed, bursting transversely.
Fertile fronds leaf-like below, sporangia in clusters at their summits.
In certain wild ravines of Central New York, at the foot of shaded limestone cliffs, the glossy leaves of the Hart's Tongue are actually weighed down by the brown, velvety rows of sporangia which emboss their lower surfaces.
Eventually it produces fronds which bear on their lower surfaces the sporangia containing the minute spores from which spring the prothallia.
The adult frustules are the smaller ones; it is from them that the sporangia are produced.
Hooker to be the sporangia of a cryptogamic land-plant, probably lycopodiaceous.
Portion of a section, showing the large sporangia in their natural position, and each supported by its bract or scale.
While this is in process of growth, peculiar oval capsules or sporangia (usually 2 to 5 in number) are formed in close proximity to the antheridium.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "sporangia" in a variety of sentences. We hope that you will now be able to make sentences using this word.
