The North American Slime-Moulds; A Descriptive List of All Species of Myxomycetes Hitherto Reported from the Continent of North America, with Notes on Some Extralimital Species (Paperback)

Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: THE NORTH AMERICAN SLIME-MOULDS THE MYXOMYCETES (Link) DeBary Chlorophyl-Iess organisms whose vegetative phase consists of a naked mass of multinuclear protoplasm, the plaimodium; reproduced by spores which are either free or more commonly enclosed in sporangia, and which on germinating produce ciliated or amoeboid zoospores, whose coalescence gives rise to the plasmodium. The Myxomycetes are,? A. Parasites, in the cells of living plants . . . Phytomyxin.k B. Saprophytes, developed in connection with decaying vegetable matter: a. With free spores Exosporeje b. With spores in receptacles or sporangia . . Myxogastres Sub-Class PHYTOMYXIN/E Schroeter 1889. Phytomyxinae Schroeter, Engl. a. Prantl., I., i., pp. 1 and 5. The parasitic Myxomycetes affecting plants include but few (four or five) species, distributed among four genera. All are parasites in the cells of particular hosts; their vegetative phase is plasmodial and their spores are formed by the simultaneous breaking up of the plasmodium into an indefinite number of independent cells. But a single genus need here concern us,? Plasmodiophora Woronin 1879. Plasmodiophora Woronin, Pringsh. Jahrb., XI., p. 548. Parasitic in the parenchymatous cells of the roots of living plants, causing noticeable enlargement of the affected organ, producing at length galls, knots, and various deformities and distortions. Spores spherical, smooth, colorless, 16 /t. I. Plasmodiophora Brassic Woronin. 1879. Plasmodiophora bratsicae Woronin, op. rit. This species, typical of forms so far reported in this country, infests the roots of cabbages,1 and produces a very serious disease of that vegetable. In England the malady has long been known under the names "clubbing," "fingers and toes," etc. The roots affected swel...