. Fungi; their nature, influence, and uses;. Fungi. STBUCTURE. 45 less warted and brownish, the contents of which become dif- ferentiated into vivacious zoospores, capable, when expelled, of moving in water by the aid of vibratile cilia. A similar struc- ture has already been indicated in Oystopus, otherwise it is rare in fungi, if the Saprolegniei be excluded. In Botrytis and in Polyaciis, the flocci and spores are similar, but the branches of the threads are shorter and more compact, and the septa are more common and numerous ; the oogonia also are absent. De Bary has selected Polyactis cine
. Fungi; their nature, influence, and uses;. Fungi. STBUCTURE. 45 less warted and brownish, the contents of which become dif- ferentiated into vivacious zoospores, capable, when expelled, of moving in water by the aid of vibratile cilia. A similar struc- ture has already been indicated in Oystopus, otherwise it is rare in fungi, if the Saprolegniei be excluded. In Botrytis and in Polyaciis, the flocci and spores are similar, but the branches of the threads are shorter and more compact, and the septa are more common and numerous ; the oogonia also are absent. De Bary has selected Polyactis cinerea, as it occurs on dead vine leaves, to illustrate his views of the dual- ism which he believes himself to have discovered in this species. " It spreads its mycelium in the tissue which is becom- ing brown," he writes, " and this shows at first essentially the same construc- tion and growth as that of the mycelium filaments of Aspergillus.'' On the my- celium sooa appear, besides those which are spread over the tissue of the leaves, strong, thick, mostly fasciculate branches, which stand close to one another, break- ing forth from the leaf and rising up per- pendicularly, the conidia-bearers. They grow about 1 mm. long, divide them- selves, by successively rising partitions, into some prominent cylindrical linked cells, and then their growth is ended, and the upper cell produces near its point three to six branches almost stand- ing rectangularly. Of these the under ones are the longest, and they again shoot forth from under their ends one or more still shorter little branches. The nearer they are to the top, the shorter are the branches, and less divided; the upper ones are quite branchless, and their length scarcely exceeds the breadth of the principal stem. Thus a system of branches appears, upon which, on a small scale, a bunch of grapes is represented. All the twigs soon end their. Fia. 28.—Polyactis cinerea. a. Apex of Please note that these ima
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