[118] Driesch’s figures seem to show, nevertheless, that the archenterons are proportionately too large. [119] These may be pieces that were cut obliquely, as Driesch suggests, so that they contain a part of the archenteric region. [120] Driesch, Hertwig, Roux, Weismann, Barfurth. For review see Driesch (’95). [121] Bunting (’94) also found that isolated blastomeres of hydractinia make whole embryos. [122] If the yolk of the dividing egg is partially withdrawn without disturbing the blastomeres, the form of the cleavage may be altered, but a normal whole embryo develops over the smaller yolk sphere. [123] We offered as a possible explanation in this case that the egg had been cut in two symmetrically with reference to the eccentric nucleus. [124] These experiments have been quite fully described in my book on _The Development of the Frog’s Egg_. [125] Not, however, the supposed action of gravity on the egg. [126] As stated in my article on “The Problem of Development,” 1900. [127] According to Roux. [128] According to E. B. Wilson. [129] 1897. [130] Unless it produces a physical change in the structure. [131] Stevens (’01) has found that this ball of red pigment is ejected from the mouth of the new hydranth. [132] The importance of this conception is, in my opinion, marred by the fiction of the ferment action of the nucleus; but it should not be overlooked that Driesch avowedly called this a pure fiction. [133] Not that Driesch supposes this would be the case. End of the Project Gutenberg EBook of Regeneration, by Thomas Hunt Morgan