. The essentials of botany. Botany. sa BOTANY as the typical form, of the vessels of tracheary tissue. Ringed and reticulated vessels are opposite modifications of the spiral form; the first are due to an under-develop- ment of the thickening in the young vessels, resulting in the production here and there of isolated rings (Pig. 30, v); reticulated vessels are due, on the contrary, to an over-development, which gives rise to a complex branch- ing and anastomosing of the spirals (Fig. 20, v'""). 52. (3) Scalariform Vessels. — These are prismatic vessels whose walls are thickened in s
. The essentials of botany. Botany. sa BOTANY as the typical form, of the vessels of tracheary tissue. Ringed and reticulated vessels are opposite modifications of the spiral form; the first are due to an under-develop- ment of the thickening in the young vessels, resulting in the production here and there of isolated rings (Pig. 30, v); reticulated vessels are due, on the contrary, to an over-development, which gives rise to a complex branch- ing and anastomosing of the spirals (Fig. 20, v'""). 52. (3) Scalariform Vessels. — These are prismatic vessels whose walls are thickened in such a way as to form transverse ridges. They are wide in transverse diameter, and their extremities are fusiform or truncate (Pig. 31). 53. (3) Pitted Vessels.—Th& walls of these. Fig. 21. Fio. 22. FiQ. 21.—Scalariform vessels of the common Brake (Pteria'). ^P'**«"i J<=ssels of Dutchman's-pipe <Aristolochia'sipho1 frnm a longitudinal section of the stem; the vessel on the right is seen in seJ? tion, that on the left from without, a, a, rings, which are rlmSants of the original transverse partitions; b, 6, sections of the walls '*'™'^'^"^= °i. 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 Bessey, Charles E. (Charles Edwin), 1845-1915. New York : Holt
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbotany, bookyear1896
