RMRHYKM7–. Beginners botany. Botany. Fig. 256. — Common Polypode Fern. Polypodium vulgare. Fig. 257. —Sori and Spo- rangium of Polypode. A chain of cells lies along the top of the sporangium, which springs back elasti- cally on drying, thus dis- seminating the spores.. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.. Bailey, L. H. (Liberty Hyde), 1858-1954. Toronto : Macmillan
RF2HB8N94–Tubifera ferruginosa, known as raspberry slime mold
RMRDWEJX–. Nature and development of plants. Botany. 390 GAMETOPHYTE OF ANGIOSPERMS vided with walls and consist of a rather larger cell, the female gamete, and two nourishing cells, the synergids or helpers (Fig. 271). The inner group or antipodal cells usually have walls and they are either soon disorganized and absorbed by the enlarging gametophyte or they may remain as permanent features of the gametophyte for a long time and even increase greatly in number, serving to nourish the gametophyte by absorbing food from the sporangium. The endosperm nucleus plays a very important role in the development
RF2HB7MY1–Tubifera ferruginosa, known as raspberry slime mold
RMRDWG3A–. Nature and development of plants. Botany. 226 SPORANGIUM OF PHILOBOLUS in this mode of scattering the spores is seen in a related form, Pilobolus, which is of common occurrence upon horse dung. Here the wall of the sporangium, unlike Rhizopus, is quite firm and becomes mucilaginous only at the point of contacfwith the stalk that bears it. Owing to the accumulation of water in the stalk such a pressure is finally set up as to rupture it at the mucilaginous point and so the sporangium with its contained spores is hurled considerable distance^—often quite one meter. The sporangia bearing stalks
RMRE3D9J–. Introduction to cryptogamic botany. Cryptogams. INTRODXJCTION TO CRTPTOGAMIC BOTANY. 511 oblique. The strongest arguments in favour of the notion are derived from the production of bulbs or young plants upon the fronds, especially as sometimes happens in place of sori. It is true that the sporangium at first consists of a single cell, but so does the leaf of a PhsEnogam, and the spores are formed by cell-division, exactly like the pollen in an anther, which is confessedly a metamorphosed leaf I do not, therefore, see the same objection to the appHcation of the doctrine of me- tamorphosis in
RMRDA85B–. Beginners' botany. Botany. Fig. 274. — MucoR. , sporangium; 3, sporangium bursting; c', columella. delicate stalk, the sporangiophore. The stalk is separated from the sporangium by a wall which is formed at the base of the spo- rangium. This wall, however, does not extend straight across the thread, but it arches up into the sporangium like an inverted pear. It is known as the col- umella, c. When the sporangium is placed in water, the wall immediately dissolves and allows hundreds of spores, which were formed in the cavity within the sporangium, to escape, b. All that is left of the fruit i
RF2WDW4AX–Trichia varia, a slime mold from Finland, no common English name
RMRH83G8–. Botany of the living plant. Botany. 25^ BOTANY OF THE LIVING PLANT The ovule at the period when it is ready for fertihsation is more or less oval in form, and it is seated upon a stalk, the funiculus, which is usually short (Fig. 206). It consists of a central body of conical form, which is called-the nucellus. This is the actual mega-sporangium. It is invested by one, and frequently by two integuments^ which are attached to its base, and cover it closely, leaving only a very narrow channel. Fig. 206. Median longitudinal section of an ovule of Caltha, at the period of fertilisation. /=funicu
RF2T7B43Y–Tubifera ferruginosa, commonly known as raspberry slime mold
RMRDF1EC–. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. So8 MOSSES AND FERNS CHAP. oped vascular bundle, which is continued into the stem as a leaf-trace, and joins the axial cylinder. The Sporangium (Bower {15)) There has been much disagreement as to the morphological nature of the sporangiophores of the Psilotaceae. The two chief views are the following: (i) That the whole sporangio- phore is a single foHar member; (2) that it is a reduced axis. ^FiG. 294.—Tmesipteris tannensis. A, Radial section of the young sporanglophore, X112; sy, the young s
RF2T7B449–Tubifera ferruginosa, commonly known as raspberry slime mold
RMRDY7X9–. Botany of the living plant. Botany. 258 BOTANY OF THE LIVING PLANT The ovule at the period when it is ready for fertihsation is more or less oval in form, and it is seated upon a stalk, the funiculus, which is usually short (Fig. 206). It consists of a central body of conical form, which is called the iiucellus. This is the actual mega-sporangium. It is invested by one, and frequently by two integuments, which are attached to its base, and cover it closely, leaving only a very narrow channel. Fig. zob. Median longitudinal section of an ovule of Caliha, at the period of fertilisation. /=funic
RF2WFDB17–Ceratiomyxa fruticulosa, commonly known as white coral, slime mold from Finland
RMRFR8MX–. Carnegie Institution of Washington publication. 110 THE OPHIOGLOSSALES sterile lamina. In the larger species, like B. virginianum, many hundred sporangia may be developed upon a single sporangiophore. In these larger and more special- ized forms the sporangium is usually smaller and is better differentiated, always having a more or less distinct pedicel. The form of the sporangiophore in Helminthostachys is to some extent inter- mediate between that of Ophioglossum and Botrychium, but on the whole comes nearer to Botrychium. The sporangia are densely crowded along the Hanks of the spike, thu
RF2P8AWKF–Reticularia lycoperdon, also called Enteridium lycoperdon, commonly known as the false puffball, slime mold from Finland
RMRE0PD3–. Nature and development of plants. Botany. 390 GAMETOPHYTE OF ANGIOSPERMS vided with walls and consist of a rather larger cell, the female gamete, and two nourishing cells, the synergids or helpers (Fig. 271). The inner group or antipodal cells usually have walls and they are either soon disorganized and absorbed by the enlarging gametophyte or they may remain as permanent features of the gametophyte for a long time and even increase greatly in number, serving to nourish the gametophyte by absorbing food from the sporangium. The endosperm nucleus plays a very important role in the development
RF2HAHM67–Lepidoderma tigrinum, known as spotted tiger slime mold, early development phase
RMRH8DHH–. Botany of the living plant. Botany; Plants. GREEN ALGAE 369 of their branches together, as in Codium, or by cementing those branches together, as in Halimeda. But these are concessions to an essentially weak construction. It is only possible to carry it to any considerable size when living in water, and all the larger forms are marine. Vaucheria is an exception : for though many of its. Fig. 27t. Vaucheria sessilis. A = young sporangium. B= zoospore, with the spor- angium from which it has escaped. C =a portion of the peripheral zone of a zoo- spore. D = a young plant, with rhizoids, develop
RF2HBNMR4–Lepidoderma tigrinum, known as spotted tiger slime mold, early development phase
RMRPWXPY–. Text-book of botany, morphological and physiological. Botany. TILICINEM. 479 sporangia, the inner ones only microsporangia, the former containing a large number of macrospores. Both kinds of sporangia are imperfectly chambered by bands of tissue {trabecules) which cross from the ventral to the dorsal side. The sporangia do not dehisce, but the spores escape by the decay of the wall. In the Selaginellece the sporangia are shortly stalked roundish capsules. The macrosporangia contain usually four, less often two or eight macrospores. In the division of Articulatse the lowermost sporangium only
RF2HAHM64–Lepidoderma tigrinum, known as spotted tiger slime mold, early development phase
RMRPXJJB–. Text-book of botany, morphological and physiological. Botany. FILICINFJE. 455. out beyond it into a pencil of delicate filaments; three (or three times three) large masses of it are attached at this point. The frothy mucilage with its cavities full of air thus forms a float for the macrospore, and bears on its surface the upper part of the ruptured sporangium. The sporocarps of the Marsiliaceae are much more complex and more firmly constructed than those of the preceding family. The sporocarp of Pilularia is a shortly-stalked spheroidal capsule, standing apparently by the side of a leaf towa
RF2H915B0–White coral slime mold, Ceratiomyxa fruticulosa, early development phase
RMRFA3JH–. Catalogue of the fossil plants of the Glossopteris flora in the Department of geology. Paleobotany -- Carboniferous; Paleobotany -- Catalogs and collections; Plants, Fossil -- Catalogs and collections. Fig. 13.—Sporangium-like organs of Glossoptcris Browniana, Brong. V. 7202 and V. 7211. x 35. a number of considerations there is little doubt that they were of the nature of spores, and the sacs themselves sporangia.. Fig. 14.-—Sporangium-like organs of Glossoptcris Browniana, Brong., which have dehisced, viewed from the inner surface. 39,149. x 30. There can hardly be any hesitation in attrib
RF2HA477M–Tubifera ferruginosa, known as raspberry slime mold
RMRE0R68–. The Eusporangiatae; the comparative morphology of the Ophioglossaceae and Marattiaceae. Ophioglossaceae; Marattiaceae. no THE OPHIOGLOSSALES Sterile lamina. In the larger species, like B. virgtntanum, many hundred sporangia may be developed upon a single sporangiophore. In these larger and more special- ized forms the sporangium is usually smaller and is better differentiated, always having a more or less distinct pedicel. The form of the sporangiophore in Helminthostach s is to some extent inter- mediate between that of Ophioglossum and Botrychium, but on the whole comes nearer to Botrychi
RF2BF4PXK–Stemonitopsis typhina (prev. Comatricha typhoides), a slime mold of the order Stemonitida, early development phase
RMRDYDHH–. Plant life and plant uses; an elementary textbook, a foundation for the study of agriculture, domestic science or college botany. Botany. 420 THE VASCULAR PLANTS. Fig. 211. — Shows the method by which the sporangium, by means o( its an- nulus, discharges the spores. ture is produced by a spore, it is, of course, a gametophyte. The prbthallia of true ferns are small, heart-shaped, flat, green bodies. (See Figure 212.) They produce their archegonia and antheridia on the under surface. (See Figure 213.) The sperms of pteridophytes are larger than those of bryophytes and have many cilia. The arc
RF2A811PP–Didymium melanospermum, a slime mold growing on sphagnum moss in Filnad
RMRDXF7K–. The origin of a land flora, a theory based upon the facts of alternation. Plant morphology. 502 FILICALES this species that the incipient stages of germination have been observed within the sporangium, a fact held to show its Fern-nature, while its other characters relate it to the Botryopterideae. The sporangia have been successfully observed in Zygopteris by Renault (Fig. 272). They were borne in groups on the ends of the pinnules, and were pear-shaped and slightly curved. The stalk, though elongated, was fairly robust, and widened gradually into the sporangial head. The latter was compose
RF2A76A47–Didymium melanospermum, a slime mold growing on sphagnum moss in Filnad
RMRDW8DW–. An introduction to vegetable physiology. Plant physiology. 440 VEGETABLE PHYSIOLOGY opens a little at the apex when the archegonia are mature, in order that fertilisation may be possible. When we pass to the Spermophytes two further advances may be seen. The spore never escapes from the sporangium, and the prothallium does not emerge even in part from the spore, which does not open. In these plants the megaspore is represented by the cell known formerly as the emhryo-sac, the sporangium being the ovule. Among the Spermophytes we have two types of prothallium which are characteristic. Fia. 17
RF2A811PE–Didymium melanospermum, a slime mold growing on sphagnum moss in Filnad
RMRE2MAW–. Elementary botany. Botany. Fig. 337. Fig-33S. Base of leaf of isoetes, Section of plant of Isoetes engelmanii, showing cup- showing sporan,t<ium with shaped stem, and longitudinal sections of the sporan- macrospoi-cs. (Isoetes en- gia in the thickened bases of the leaves, gelmannii.) ure from the other portions of the leaf. This is a sporangium. Beside the spores on the inside of the sporangium, there are strands of sterile tissue which extend across the cavity. This is peculiar to isoetes of all the members of the class of jilants to which the ferns belong, but it will be remembered that
RF2A76A3Y–Didymium melanospermum, a slime mold growing on sphagnum moss in Filnad
RMRDWFDG–. Elementary botany. Botany. Kig. 249. Base of leaf of isoetes, showing sporangium with macrospores. (isoetes en- gelmannii.). Fig. 250. Section of plant of Isoetes engelmanii, showing cup- shaped stem, and longitudinal sections of the sporan- gia in the thickened bases of the leaves. ure from the other portions of the leaf. This is a sporangium. Beside the spores on the inside of the sporangium, there are strands of sterile tissue which extend across the cavity. This is peculiar to isoetes of all the members of the class of plants to which the ferns belong, but it will be remembered that ster
RFH6D1T8–Dog vomit slime mold or mould, Fuligo septica
RMRF28RY–. Catalogue of the fossil plants of the Glossopteris flora in the Department of geology. Paleobotany -- Carboniferous; Paleobotany -- Catalogs and collections; Plants, Fossil -- Catalogs and collections. 42 GLOSSOrTElUS. These organs are sac-like structures, and dehisced longitudinally. Their contents have not, however, heen recognised, but from I Ills ill mill (its m. Fig. 13.—Sporangium-like organs of Glossoptcris Browniana, Brong. V. 7202 and V. 7211. x 35. a number of considerations there is little doubt that they were of the nature of spores, and the sacs themselves sporangia.. Please not
RFH96F21–Dog vomit slime mold or mould, Fuligo septica
RMRD64T0–. The cyclopædia of anatomy and physiology. Anatomy; Physiology; Zoology. REPRODUCTION, VEGETABLE (VEGETABLE OVUM). spore membrane, and consequently formed before it, line the inner surface of the parent Fig. 173.. Development of parent cells of the spores of the same- a, one of the nucleated cells which constitute the central mass of the young sporangium; b, the central nucleus has disappeared, and is replaced by four others, one of which is out of focus; c, the cell is divided by six septa into four somewhat tetrahedral compartments. This ob- ject has by mistake been represented relatively s
RFH6D1T5–Dog vomit slime mold or mould, Fuligo septica
RMRDXFA2–. The origin of a land flora, a theory based upon the facts of alternation. Plant morphology. SPORE-PRODUCING MEMBERS 455 simpler, or reduction from a more complex type, may be a question for discussion; but it is clear that the gradually transitional forms do exist. As regards the first appearance of the sporangium, the essential parts of it, though not the whole body, are normally referable to a single parent-cell, and the first periclinal division delimits the sporogenous tissue (see Figs. 43, 44, p. 88). It appears that here all the sporogenous cells undergo the tetrad-division, and the no
RF2P0MH2J–Stemonitopsis typhina, also called Comatricha typhoides, a slime mold of the order Stemonitida, immature specimen from Finland
RMRE1R4P–. Nature and development of plants. Botany. DEVELOPMENT OF PLANTS 225 and so become spores (Fig. 135). The numerous sporangia filled with dark spores are the principal cause of the black color of these fungi. During the development of the spores a wall is constructed over the central protoplasm, thus often forming a dome-like structure in the sporangium known as the columella (Fig. 135, E). The walls of the sporangia (save at the region in contact with the stalk) readily dissolve in the presence of moisture, owing to their mucilaginous character, and thus allow the spores to float off in the a
RF2HA477F–Tubifera ferruginosa, known as raspberry slime mold
RMRDFBGR–. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. 390 MOSSES AND FERNS CHAP. major part from the cap cell, which in all the forms becomes much more developed than in any other Ferns, and from it alone the apical annulus is derived. In Ancimia and Mohria the tissue of the tip of the leaf adjacent to the sporangia grows into a continuous indusium, which pushes them under to the lower side. In Lygodium (Fig. 224) each sporangium very evidently corresponds to a single lobe of the leaf segment, and has a vein corresponding to this. The pocket-like
RF2E3YRRT–Reticularia lycoperdon (Enteridium lycoperdon), the false puffball slime mold
RMRDFBH4–. The structure and development of mosses and ferns (Archegoniatae). Plant morphology; Mosses; Ferns. FlG. 227.—Cibotium Memiesii. A, Pinnule with the sori is), X3; B, a single sorus showing the two-valved indusium, X9;- C, a single sporangium, X80; r, the annulus; D, a paraphysis, X8o. dium, less so in Schiscea, where the sporangia are smaller, and the mother cells project much more strongly. The early divi- sions correspond closely with those of the Hymenophyllaceas, and as there the tapetum is massive and two-layered, and the stalk of the sporangium very short. The wall is derived in The di
RF2E3YRT1–Reticularia lycoperdon (Enteridium lycoperdon, the False Puffball slime mold releasing its spores
RMRDYE4R–. A textbook of botany for colleges and universities ... Botany. SPERMATOPHYTES 259. Fig. 579. — Transverse section of a young anther of lily, showing the four sporangia well advanced. — After Coulter. spores of a sporangium cling together in one mass, called the pollinium. As the four sporangia of an anther increase in size (fig. 579), the sterile tissue separating the two sporangia on each side of the anther breaks. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may
RF2BX8CF6–Bartramia pomiformis, the common apple-moss, photographed in winter in Finland
RMRH93PB–. Botany for agricultural students. Plants. Fn;. 290. — Various Myxomycetes, showing various types of sporangia. The large sporangium at the left and the third one from the left, below, have shed the spores, and the capillitium, the lace-like framework of the sporangium, is i)lainly visible. The larger ones are larger than natural size, the smaller ones are reduced. From Kerner. the projections. The protoplasm filling the upper part of each projection forms numerous, small, globular spores with heavy 0 5 8. Fig. 291.—Spores of a My.xomycete germinating and producing motile animal-like bodies w
RF2BX8CEY–Bartramia pomiformis, the common apple-moss, photographed in winter in Finland
RMRDWY6E–. A general system of botany, descriptive and analytical. In two parts. Part I. Outlines of organography, anatomy, and physiology. Part II. Descriptions and illustrations of the orders. By Emm. Le Maout [and] J. Decaisne. With 5500 figures by L. Steinheil and A. Riocreux. Translated from the original by Mrs. Hooker. The orders arranged after the method followed in the universities and schools of Great Britain, its colonies, America, and India; with additions, an appendix on the natural method, and a synopsis of the orders, by J.D. Hooker. Botany. /. setacea. Vertical section of a sporangium, e
RF2BER5JX–Lepidoderma tigrinum, known as spotted tiger slime mold, maturing sporangia from Finland
RMRD2F9H–. Elementary botany. Botany. i68 MORPHOLOGY. is termed the annulus, which means a little ring. While this is not a complete ring, in some other ferns the ring is nearly complete. 350. In the front of the sporangium is another peculiar group. Fig. 205. Rhizome of sensitive fern (Onoclea sensibilis). of cells. Two of the longer ones resemble the lips of some crea- ture, and since the sporangium opens between them they are sometimes termed the lip cells. These lip cells are connected with the upper end of the annulus on one side and with the upper end of the stalk on the other side by thin-walled
RF2BER5JC–Lepidoderma tigrinum, known as spotted tiger slime mold, maturing sporangia from Finland
RMRE2F76–. Fundamentals of botany. Botany. 420 STRUCTURE AND LIFE HISTORIES that the ovuUferous scale represents two sporophylls fused together. 372. Megasporangia.^—As in Cycas, the megaspor- angium is an ovule, comprising a nucellus (sporangium proper), surrounded by an integument. At the apex the integument does not come quite together, so that a. Fig. 310.—Median longitudinal section of a pine cone, scale; 011, ovule at the base of a scale. o.s, ovuliferous tiny opening or pore (the micropyle) is left. The micropyle leads to^the pollen-chamber below (Figs. 309 and 311). The megaspores are more back
RF2HX7RGE–Golden slime mold, Physarum viride var. aurantiacum
RMRE2F4N–. Fundamentals of botany. Botany. SEED-BEARING PLANTS 453 403. Essentials of a Seed.—In the cycads and pines we have seen accomplished the first step necessary for the production of a true seed, namely, the retention within the sporangium of the megaspore and the female gameto- phyte to which it gives rise. The final step was the forma- tion of an embryo, which usually rests (before proceeding to develop into an adult sporophyte. With few excep- tions, the distinctive feature of a seed is a resting embryo. The embryo may or may not be surrounded by nourish-. FiG. 337.—John Ray (1628-1705). An
RFH9EC96–Red raspberry slime mold or mold, Tubifera ferruginosa
RMRDYEE5–. A manual of poisonous plants, chiefly of eastern North America, with brief notes on economic and medicinal plants, and numerous illustrations. Poisonous plants. 160 MANUAL OF POISONOUS PLANTS a shorter or longer period the protoplasm contracts forming little heaps which contain the spores; the parts of the reproductive body are called the sporangium or spore case, the peridium or the wall of the case, the stipe or stalk, the columella or central axis in the spore case, the capillitium or fine threads, and the spores. The spores after absorbing water, germinate by breaking the wall and move a
RF2T97760–Physarum viride, a slime mold, microscope image of sporangia
RMRR278F–. Advanced biology. Biology; Physiology; Reproduction. '«d An aerial hypha develops a sporangium or fruiting body. This structure produces and disperses the spores. A sporangium some- times forms at one end of the hypha. The pro- toplasm within this end breaks into a great many tiny structures, spores. When ripe, this fruiting body or spore case, the sporangium, breaks open and the spores scatter. The spores can outlast unfavorable conditions. During unfavorable conditions, the mold is in a dormant or resting stage in the spore. If it settles on food and there are proper conditions of moisture
RF2NHXHG6–Trichia varia, a slime mold from Finland, no common English name
RMRDCY4P–. Botany for agricultural students . Botany. PINES (PINACEAE) 451 maining portion of the nucellus hardens, so that the seed when mature resembles some of the stone fruits, such as the Plum, although it is a seed and not a fruit. It is obvious that a seed is simply a transformed megaspo- rangium. In the Cycads a seed is a megasporangium which has its outer portions modified for protection and contains within a female gametophyte bearing a . young sporophyte. Thus the re- duction of the female gametophyte through the Pteridophytes and finally its retention in the mega- sporangium in the Cycads s
RF2NKXC5R–Stemonitopsis typhina, also called Comatricha typhoides, a slime mold of the order Stemonitida, immature specimen from Finland
RMRDBCGM–. Studies in fossil botany . Paleobotany. STAUROPTERIS 339 homosporous sporangia or microsporangia. A year previously a case had been observed in which spores were found germinating inside an isolated sporangium, the stages agreeing with those found in recent Ferns.1 Subsequently, similar stages of germination were de- tected in typical sporangia of Stauropteris oldhamia, establishing a strong presumption that this plant also was a true homosporous Fern.2 Some of the germinat-. Fig. 128.—Stauropteris oldhamia. Four germinating spores from the interior of a sporangium. All four are putting out
RF2HCKTBB–Reticularia lycoperdon, also called Enteridium lycoperdon, commonly known as the false puffball, slime mold from Finland
RMREK7RH–. The classification of flowering plants. Plants. IV] ANGIOSPERMS 147 and appears to contain longitudinal series of pollen-sacs. This occurs in many Leguminosae of the Mimosa section (fig. 68, L) and others, and recalls the segmentation by sterile tissue in the sporangium of Isoetes. Each of the spore-mother-cells divides to form four special mother-cells, in each of which a microspore is produced. In most Monocotyledons the process is one of successive cell-divi- sion. The first division of the spore-mother-cell is followed by the formation of a wall separating the daughter-cells, and the nex
RF2E4D48G–Metatrichia vesparium, commonly known as wasp nest slime mold
RMRDYFD4–. A textbook of botany for colleges and universities ... Botany. 140 MORPHOLOGY. cells contribute to the nutrition of 40-75 mother cells that function. These mother cells become relatively very large and produce large spores, the total output of megaspores being 150-300 (fig. 317). Both kinds of spores escape by the decay of the sporangium wall. Male gametophyte.—The male gametophyte is still more simple than that of Selaginella (figs. 318-320). It consists of a single vegetative cell and a single antheridium, as in Selaginella; but the sperm mother cells are only four in number. This is the l
RF2E1PHG7–Metatrichia vesparium, commonly known as wasp nest slime mold
RMRDXY29–. Principles of modern biology. Biology. 204 - Multicellular Plants. Fig. 12-1. The familiar fern plant is the sporophyte generation, consisting of exposed leaves (fronds), an underground stem (the rhizome), and the roots. (From The Plant World, by Fuller and Carothers. Holt, Rine- hart and Winston, Inc.) cluster of spore capsules, or sporangia. At higher magnification one can see that each sporangium is a hollow structure, containing numerous spores (Fig. 12-3). While a spo- rangium is ripening, the spores are produced from spore mother cells, or sporocytes. The spore mother cell undergoes me
RF2E1PHFN–Stemonitopsis typhina, also called Comatricha typhoides, a slime mold of the order Stemonitida, immature specimen from Finland
RMRDD7WK–. Botany for agricultural students . Botany. SOME MYXOMYCETES OF ECONOMIC IMPORTANCE 339 After the spores are mature, the wall of the sporangium breaks open and the spores are scattered far and near by wind, animals, and other agencies. When the spores fall on a suitable object and conditions are right, the protoplasm breaks out of the heavy- wall and either grows directly into a new Plasmodium, or pro- duces cilia, swims about, and multiplies like the simple one-celled forms of animals {Fig. 291), the Plasmodium being formed later by the fusion of these animal-like bodies. Some Myxomycetes of
RF2E2GB20–Stemonitopsis typhina, also called Comatricha typhoides, a slime mold of the order Stemonitida, immature specimen from Finland
RMRE1PHX–. Nature and development of plants. Botany. FlG. 223. Section of a leaf of Woodwardia, showing two sori: i, indusiura; sp, sporangia arising from the epidermis and in various stages of develop- ment. Note the epidermis, stoma, s, palisade and spongy chlorenchyma and vascular bundles, as in higher plants. phyta, and it is evident that ample provision is made for the maintenance of the race notwithstanding the postponement and specialization in spore production. The sporangia vary considerably in structure in the various. Fig. 224. Character of sporangia: A, simple type of sporangium of Osmunda
RF2E1PHFA–Stemonitopsis typhina, also called Comatricha typhoides, a slime mold of the order Stemonitida, immature specimen from Finland
RMRDWYM8–. A general system of botany, descriptive and analytical. In two parts. Part I. Outlines of organography, anatomy, and physiology. Part II. Descriptions and illustrations of the orders. By Emm. Le Maout [and] J. Decaisne. With 5500 figures by L. Steinheil and A. Riocreux. Translated from the original by Mrs. Hooker. The orders arranged after the method followed in the universities and schools of Great Britain, its colonies, America, and India; with additions, an appendix on the natural method, and a synopsis of the orders, by J.D. Hooker. Botany. N^hrodium. Nephrodium. Sporangium Dehiscing spo
RF2E2GE6H–Stemonitopsis typhina, also called Comatricha typhoides, a slime mold of the order Stemonitida, immature specimen from Finland
RMRDC2GX–. Diseases of plants induced by cryptogamic parasites : introduction to the study of pathogenic Fungi, slime-Fungi, bacteria, & Algae . Plant diseases; Parasitic plants; Fungi. PROTOMYCES. 139 distributing itself through the intercellular spaces, stimulates the parenchyma-cells of the host to growth and cell-division. The. Fig. 45.—Trotomyces macrosporus on leaf-stalk of Aegopodium Podagraria. A, Mycelium and sporangium in the tissue xinder the epidermis. S, Sporangia in stages of development, (v. Tubeuf del.) latter is a secondary process and consists (see Fig. 9) in the formation of exce
RF2E1PHF9–Stemonitopsis typhina, also called Comatricha typhoides, a slime mold of the order Stemonitida, immature specimen from Finland
RMRHYKF0–. Beginners botany. Botany. STUDIES IN- CRYPTOGAMS 189. Fig. 274. — MucoR. I sporangium; bursting; c b, sporangium , columella. delicate stalk, the sporangiophore. The stalk is separated from the sporangium by a wall which is formed at the base of the spo- rangium. This wall, however, does not extend straight across the thread, but it arches up into the sporangium like an inverted pear. It is known as the col- umella, c. When the sporangium is placed in water, the wall immediately dissolves and allows hundreds of spores, which were formed in the cavity within the SDorangium, to escape, b. All
RF2E2GB0D–Stemonitopsis typhina, also called Comatricha typhoides, a slime mold of the order Stemonitida, immature specimen from Finland
RMRH8PCG–. Botany of the living plant. Botany; Plants. 49§ BOTANY OF THE LIVING PLANT are readily scattered. Since each of the 12 spore-mother-cells forms four spores, their number is 48 in each sporangium. Each mature spore consists of a nucleated protoplast, bounded by a colourless inner wall, and a brown epispore bearing irregular projecting folds. Meanwhile the wall of the sporangium has differentiated into the thinner lateral walls of the lens-shaped head, and the annulus, which is a chain of about 16 indurated cells surrounding its margin (Fig. 389, 4a, 46). These form a mechanical spring, which
RF2E2GE6C–Stemonitopsis typhina, also called Comatricha typhoides, a slime mold of the order Stemonitida, immature specimen from Finland
RMRDBCEA–. Fossil plants : for students of botany and geology . Paleobotany. xiv] LYCOPODIUM 47 (fig. 126, A) to afford protection to the lower sporangia, their efficiency being increased by the lignified and thicker walls (A, a) of the cells in the lower portion of the laminar expansion. The cells of the sporangial wall are provided with strengthening bands which in surface-view (fig. 126, B) present the appearance of prominent pegs. Since the appearance of Miss Sykes's paper on the sporangium-bearing organs of the Lycopodiaceae, Dr Lang* has published a more complete account of the structure of the s
RF2ANJ9XB–Stemonitopsis typhina (prev. Comatricha typhoides), a slime mold of the order Stemonitida, early development phase
RMRDXF49–. The origin of a land flora, a theory based upon the facts of alternation. Plant morphology. OSMUNDACEAE S35 is believed to be truly comparable to the "central cell" of the Marattiaceous sporangium. The archesporial cell thus surrounded by the tissue which will form the sporangial wall undergoes segmentation to form the tapetum (Fig. 296 e and f), and the irregularity seen in other segmentations is fully maintained in this also. From a comparison of Figs. 296 f and G it will be seen that sometimes the segmentation of the tapetum is almost according to the ordinary Leptosporangiate t
RMRH84PA–. Botany for agricultural students. Plants. FEMALE GAMETOPHYTE 449 sporangium as in Selaginella, but a new feature of the Cyeads is that the megasporangiuni does not open to allow the megaspore to be exposed, and therefore the female gametophyte remains permanently enclosed in the sporangium. The developing female gametophyte uses most of the nucellus for food and thereby makes room for itself. When the gametophyte is mature the. Fig. 399. — Section through a Cycad ovule containing a mature gameto- phyte. /, female gametophyte with two archegonia (a) shown; m, micro- spores developing tubes, a
RMRDTRAC–. A monograph of the Mycetozoa, being a descriptive catalogue of the species in the herbarium of the British Museum. Illustrated with seventy-eight plates and fifty-one woodcuts. Myxomycetes. 108 ENDOSPORE^. [STEMONITACEiE. Subcohort 11.—AMAUROOH^TINE^. Sporangia single, or combined into an sethalium, without deposits of lime; capil- litium and spores dark-brown or violet-brown, rarely pale. Order I.—STBMONiTACBiE. Sporangia stipitate; sporangium- wall a simple delicate membrane, often evanescent; stalk ex- tending within the sporangium as a columella from which the branching threads of the ca
RMREF9DX–. Comparative morphology of Fungi. Fungi. 48 COMPARATIVE MORPHOLOGY OF FUNGI they come to rest on the young leaves, make a few amoeboid movements and put a short rhizoid into the epidermis. The zoospore body develops shortly into an irregularly indented sporangium, sessile as in Rhizo- phidium. At maturity its content breaks up into numerous zoospores. A part of the walls swells, bursts open and liberates the zoospores. Under favorable conditions, a new sporangium may grow five or six times from the rhizoid into the emptied sheath. In the formation of hypnospores the content of the zoospores p