. The American florist : a weekly journal for the trade. Floriculture; Florists. Fig. 3. Uredospores, more highly ] they p;row very closely together, parallel to each other and perpendicular to the surface of the leaf. This constitutes what is termed the stroma. These parallel threads continue to elongate, at the same time broadening at their free ends until a rounded or oval body is developed which becomes light brown in color. S\r\ii\-'\ The color resides. germinating the protoplasm inside the stout wall pushes its way out through one of the three pores always present in the wall. Sometimes
. The American florist : a weekly journal for the trade. Floriculture; Florists. Fig. 3. Uredospores, more highly ] they p;row very closely together, parallel to each other and perpendicular to the surface of the leaf. This constitutes what is termed the stroma. These parallel threads continue to elongate, at the same time broadening at their free ends until a rounded or oval body is developed which becomes light brown in color. S\r\ii\-'\ The color resides. germinating the protoplasm inside the stout wall pushes its way out through one of the three pores always present in the wall. Sometimes the proto- plasm starts to push out at all three of the pores but soon ceases to extend in all but one, where it passes out into a long thread which eventually enters the plant again if the uredo- spore is properly located. A short time after the devel- opment of the uredospores the stroma of the same sorus, espe- cially on the stem, produces a second kind of spore, termed a teleutospore. These are also one-celled bodies and possess a stout brown wall, the wall, however, is smooth; at the apex there is usually a minute projec- .^ , . tion, or spicuhts, of a lighter agnified, germmatmg. ^^,^^^ ^j^;f^ ^^ ^^^ ^^^^ ^ f^^^_ ment of the long pedicel remains at- tached after the teleutospore becomes free. The teleutospores will not germinate immediately after they are developed. Like the teleutospore of many other uredinea: they probably must first pass through a period of rest. Thus they serve as resting bodies to tide the parasite over an unfavorable thick wall, period when the uredospores or the which surrounds vegetive threads are liable to perish, and protects the While the vegetive threads, or my- delicate living pro- celium,of the rust course almost exclu- toplasm within sively between the cells of the host and is covered with they of course derive their nourish- numerous minute ment from the protoplasm within the spines, and is said cells, thus bringing about the great to be e
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectfloriculture, bookyea
