. Fungi; their nature and uses. Fungi. GERMINATION AND GROWTH. 145 production of cylindrical tubes, which start from the upper extremity of the wedge-shaped spores, or more rarely from the base. These tubes are straight or twisted, simple or bifurcated, and each of them very soon emits four monosporous spicules, at the same time that they become septate. The sporules are in this instance globose. In Uromyees germination follows precisely the same type as that of the upper cell of Puccinia; in fact, Tulasne states that it is very difficult to say in what they differ from the Puccinia which are
. Fungi; their nature and uses. Fungi. GERMINATION AND GROWTH. 145 production of cylindrical tubes, which start from the upper extremity of the wedge-shaped spores, or more rarely from the base. These tubes are straight or twisted, simple or bifurcated, and each of them very soon emits four monosporous spicules, at the same time that they become septate. The sporules are in this instance globose. In Uromyees germination follows precisely the same type as that of the upper cell of Puccinia; in fact, Tulasne states that it is very difficult to say in what they differ from the Puccinia which are accidentally unilo- cular. In Oystopus a more complex method pre- vails, which will be examined more closely hereafter. In Puccinia, as already observed when describing their structure, the pseudospores are two-celled. From the pores of each cell, which are near the central septum, springs a clavate tube, which attains two or three times the total length of the fruit, and of which the very obtuse extremity curves more or less in the manner of a crozier.* This tube, making a perfectly uncoloured transparent membrane, is filled with a granular and very pale plastic matter at ««>«"«"«""»• (Tulasne.) the expense of the generative cell, which is soon rendered vacant; then it gives rise to four spicules, usually on the same side, and at the summit of these produces a reni- form cellule. The four sporules so engendered exhaust all the protoplasm at first contained in the generative cell, so that their united capacity proves to be evidently much insufficient to con- tain it, the more so as it leads to the belief that this matter undergoes as it condenses an elaboration which diminishes its size. In all cases the spicule originates before the sporule which it carries, and also attains its full length when the sporule ap- * Tulasne, in his "Memoirs on the ;. Please note that these images are extracted from scanned page images that may hav
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