. The mechanistic conception of life; biological essays. Life; Biology. The Mechanistic Conception op Life of the aquarium, while the stems never show such a reaction. These new parts growing out from the branches of the imder side of the stem attached themselves to the solid bodies with which they came in coiitact. Moreover, they were positively geotropic (that is, they grew toward the center of the earth), while the branches never showed any positive geo- tropism. The branches on the upper side were not transformed into roots. They either per- ished or gave rise to long, slender, perfectly s
. The mechanistic conception of life; biological essays. Life; Biology. The Mechanistic Conception op Life of the aquarium, while the stems never show such a reaction. These new parts growing out from the branches of the imder side of the stem attached themselves to the solid bodies with which they came in coiitact. Moreover, they were positively geotropic (that is, they grew toward the center of the earth), while the branches never showed any positive geo- tropism. The branches on the upper side were not transformed into roots. They either per- ished or gave rise to long, slender, perfectly straight stems, which grew ver- tically upward. These stems, as a rule, were too slender to bear branches, but at parts of the upper surface of the main stem there origi- nated new stems (c d, Fig. 25), which grew vertically upward and produced the typical little branches bearing polyps. If we brought the stem into an oblique position (Fig. 26), with the apex a upward, from every element of the main stem new stems and roots originated, but with this difference, that stems always originated from the upper side of an element and roots from its lower side. If the stem were placed in an oblique position, with the root end above, the branches on the under side grew out as roots, and at the upper end a stem arose as Fig. 26.—Diagrammatic regeneration in a piece a 6 of a stem of Antennularia put ob- liquely into the water. On the upper side of the stem a b new stems S, S,, S^„ grow verti- cally upward, while at the lower end of the piece a b opposite the new stems roots W, W,. W„, grow out. This influence of gravitation is found only in Antennularia antennina, not in other forms of Antennularia,. 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 Loeb, Jacques, 1859-1924. Chicago, University of Chicago Pr
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbiology, bookyear1912
