. Plants; a text-book of botany. Botany. SI'ERMATOPHYTES : ANGIOSPERJIS 217 cotyledons, and the seed coat containing the cotyledons remains like a lateral appendage npon the straightened axis. It is also to be observed in many cases that the young root system, after gripping the soil, contracts, drawing the yonng plant deeper into the ground. 118. Summary from Angio- sperms.—At the beginning of this chapter (§ 107) the characters of the Gymnosperms were summar- ized which distinguished them from Angiosperrns, whose con- trasting characters may be stated as follows : (1) The microspore (pollen-
. Plants; a text-book of botany. Botany. SI'ERMATOPHYTES : ANGIOSPERJIS 217 cotyledons, and the seed coat containing the cotyledons remains like a lateral appendage npon the straightened axis. It is also to be observed in many cases that the young root system, after gripping the soil, contracts, drawing the yonng plant deeper into the ground. 118. Summary from Angio- sperms.—At the beginning of this chapter (§ 107) the characters of the Gymnosperms were summar- ized which distinguished them from Angiosperrns, whose con- trasting characters may be stated as follows : (1) The microspore (pollen- grain), chiefly by insect pollina- tion, is brought into contact with the stigma, which is a receptive region on the surface of the car- pel, and there develops the pollen- tube, which penetrates the style to reach the ovary cavity which contains the ovules (megasporan- gia). The impossibility of con- tact between pollen and ovule im- plies inclosed ovules and hence seeds, and therefore the name " ; (2) The female gametophyte is but slightly developed before fertilization, the egg appearing very early. (3) The female gametophyte produces no archegonia but a single naked Pig. 194. Seedling of hazel (Car- plnus), showing primary root {hw) bearing rootlets {$w) upon which are numerous root hairs (r), hypocolyl ihj, cotyledons (c), yonng stem (e), and first (/) and second (I') true leaves.—After Schim- 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 perfectly resemble the original Coulter, John Merle, 1851-1928. New York, D. Appleton and company
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