. Elements of plant anatomy;. Botany -- Anatomy. Acer, sieve- plates in a X 150, in b x 400 times, a callous substance, p protoplasm. — (Th. Hartiy.) Fig. 30. Fragments of sieve-tubes, s sieve-plate in cross-sec- tion, s' seen from the sur- face, c callous substance. X 300. —{W^itsntr.) some instances, masses of this cal- lous substance are found, covering the sieve-plate on each side, leaving no indications of the openings or pores. This substance is easily dissolved, and it is believed that by its formation the function of the sieve- plate is arrested during the period of winter inactivity,
. Elements of plant anatomy;. Botany -- Anatomy. Acer, sieve- plates in a X 150, in b x 400 times, a callous substance, p protoplasm. — (Th. Hartiy.) Fig. 30. Fragments of sieve-tubes, s sieve-plate in cross-sec- tion, s' seen from the sur- face, c callous substance. X 300. —{W^itsntr.) some instances, masses of this cal- lous substance are found, covering the sieve-plate on each side, leaving no indications of the openings or pores. This substance is easily dissolved, and it is believed that by its formation the function of the sieve- plate is arrested during the period of winter inactivity, to be resumed again in summer, the callous substance being dis- solved away. The contents of the tubes are such as to support the opinion that their function is to conduct various in- soluble materials in masses from place to In their mature condition there is a thin layer of protoplasmic substance lining the wall. The remaining Fig. 29. Piece of sieve-tube of Vitls vinifera. S S sieve-tubes. g g accompanying cells, sp compound sieve-plates with eight sieve areas, x 400. — {Accd, to Wilhelm.) place in the 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 Gregory, Emily L. Boston, London, Ginn & Co.
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbotanya, bookyear1895
