. The propagation of plants ; giving the principles which govern the development and growth of plants, their botanical affinities and peculiar properties; also, descriptions of the process by which varieties and species are crossed or hybridized, and the many different methods by which cultivated plants may be propagated and multiplied . Plant propagation. MOTEMENT AKD EEOEGAmzATION OF CELLS. 25 ripened parent stem. That these stem bulbs are the pro- duct of reorganized cell-matter, which, under other con- ditions, would hare spread out into long, thin, aerial and true leaves, is quite evident
. The propagation of plants ; giving the principles which govern the development and growth of plants, their botanical affinities and peculiar properties; also, descriptions of the process by which varieties and species are crossed or hybridized, and the many different methods by which cultivated plants may be propagated and multiplied . Plant propagation. MOTEMENT AKD EEOEGAmzATION OF CELLS. 25 ripened parent stem. That these stem bulbs are the pro- duct of reorganized cell-matter, which, under other con- ditions, would hare spread out into long, thin, aerial and true leaves, is quite evident from the fact that they are only produced at the point where an embryo leaf-bud had formed a junction with the stem. It is not only in the propagation of plants under artificial conditions that we find great uniform- ity in the movement of cell- matter proceeding from uniform causes, but it is also observable in the re- sults of attacks and injuries inflicted by insects. In the growth of what are called galls on plants, produced, so far as known, by the irri- tation caused in depositing eggs, or the presence of the larvse hatched therefrom, the results are so uniform that the entomologist is enabled, at a glance, to Pig. gaix. identify the inhabitants of galls by the structure and outward appearance of their dwellings. Why the irritation caused by the depositing of a few minute eggs by a small four-winged black fly (Gynips spongifica), on the leaf-stalk of the Black Oak should cause cell-matter to rush to that part, and form a large puffy gall an inch or more in diameter, and of a speci- fic structure, differing Avidely from those produced by a closely-related insect upon other species of the Oak, we do not know ; but the fact that every distinct species of Gynips produces a different gall is well known to every entomologist. (Figure 7—a, larva in center; b, hole where the fly escaped.). Please note that these images are extracted from scanned page images that may hav
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Keywords: ., boo, bookcentury1900, bookdecade1910, booksubjectplantpropagation
