



*889-] BOTANICAL GAZETTE. 



ing a brief recapitulation, it can be said to consist of the fol- 

 lowing assumptions : The nucleus of every cell, used in propa- 

 gation, contains all sorts of pangens of the species of animal 

 or plant to which it belongs. As all other nuclei of the full- 

 grown being owe their origin to repeated divisions of the 

 first one, they all can be in possession of a complete set of 

 pangens, which can propagate themselves when a division 

 Jakes place. In the nucleus the greatest part of them remain 

 inactive through life, with the exception onlv of those pan- 

 gens which determine the visible characters of the nucleus 

 itself, such as its peculiar mode of division, etc. 



All other organs of the protoplast essentiallv contain only 

 pangens corresponding to the characters which they are ca- 

 pable of displaying. It is, however, by no means necessary 

 that they all are at all times in an active state, as, for in- 

 stance, plastids in some cases are known to exhibit alter- 

 nately their power of forming starch and that of forming col- 

 ored matter. But, no doubt, at most times these organs con- 

 tain a large amount of active pangens. 



Inactive pangens from the nucleus can migrate to those 

 other organs of the protoplast, whose characters they repre- 

 sent ; they can again propagate themselves here, and~in most 

 cases sooner or later become active, thus bringing to light 

 •certain characters. 



This migration, as shown by the facts of sexual reproduc- 

 tion, must occur soon after fecundation has taken place, but 

 there is no reason why it could not happen in many other 

 phases of development, perhaps even every time a cell- 

 division is achieved. The author is of opinion that the 

 migration of pangens from the nucleus to other parts 01 

 the protoplast may be effected by the movements of proto- 

 plasm, to which view there is the less objection as it has been 

 lately shown that these movements are by no means wanting, 

 even in the very youngest vegetable celfs. 



From the foregoing review it is obvious that on the as- 

 sumption of intracellular pangenesis the possibility of pan- 

 gens migrating from one part of the body into other parts is 

 not at all excluded. This will be readily assented to if it is 

 recollected that of late years many facts have been accumu- 

 lated proving that the protoplasts of neighboring cells are 

 connected together by fine protoplasmic filaments passing 

 through the cell-walls. Moreover, Prof, de Vries himself 

 has rendered it highly probable that the movements of pro- 





