. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. TELEUTOSPORES 11 both (Fig. 12). The uredospore retains its capacity for germination for a longer time, even for more than three months; in fact, in certain foreign species, some of these spores acquire a thicker wall which enables them to act as a kind of resting-spore—these are called amphi- spores, but they are not formed by P. Caricis. It is found, generally, that if the spores of the Uredinales are dried gradually, they retain their power of germination for a longer time and in a better de
. The British rust fungi (Uredinales) their biology and classification. Rust fungi -- Great Britain. TELEUTOSPORES 11 both (Fig. 12). The uredospore retains its capacity for germination for a longer time, even for more than three months; in fact, in certain foreign species, some of these spores acquire a thicker wall which enables them to act as a kind of resting-spore—these are called amphi- spores, but they are not formed by P. Caricis. It is found, generally, that if the spores of the Uredinales are dried gradually, they retain their power of germination for a longer time and in a better degree than if dried quickly or not dried at all. Most likely a slow drying enables them to mature more Fig. 12. Two uredospores of P. Caricis, both germi- nating in distilled water. xl80. The Teleutospores. After a time, probably in response to the weather or other change of environment, the mycelium which has hitherto given rise only to uredospores begins to produce, at first in the same, afterwards in separate sori, the fourth kind of spore—the teleutospore. In the genus Puccinia this is almost always a compound body, formed of two superposed cells; each cell is really a spore, and is capable of independent germination. In many species of the genus the teleutospores readily break apart at the septum, in Puccinia fusca and P. Pruni- spinosae, and the lower half may be, and has been, mistaken for a uredospore. Those of P. Caricis do not easily break apart until they are old and dead. The teleutospores are formed on a pedicel, much in the same way as the uredospores, except that the uppermost cell is again divided, but apart from that they differ widely in their character. They have a thick dark-brown exospore, covered with a chitinous cuticle ; in this species the exospore. 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 perfe
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