[25] “There is thus manifested in the formative force of the tubularia-stem a well-marked polarity, which is rendered very apparent if a segment be cut out from the centre of the stem.” Allman (’64).
[26] The same holds good for the basal hydranth if it arises near an oblique end.
[27] Although it is by no means certain that the results may not be due in part, at least, to injuries to the nervous system.
[28] In normal animals some have the right claw the larger and some the left.
[29] In other plants, fumaria, for example, non-nucleated pieces do not seem to be able to make new starch after using up that which they contain at first.
[30] I have found that the closing in takes place equally well when one per cent of KCl is added to the sea water. This salt has, as Loeb has shown, an inhibiting effect on muscular contractility,—not, however, on amœboid movements.
[31] Knight obtained similar results in 1809.
[32] Vöchting points out that a parallel case is found in certain conifers. In these there arise from a vertical many-sided main stem whorls of side branches that are symmetrical in one plane. These lateral branches, if cut off and planted, produce new roots and new branches, but the latter are always side-branches, like the parts from which they arise. They never produce a normal main axis. Nevertheless, although these branches cannot themselves produce a main shoot, a callus may be formed at the base of the piece, and from this a new main stem may arise.
[33] A piece suspended in ordinary air dries up without producing any new structures.
[34] Goebel, ’98, page 37.