CHAPTER XIV. 



EEPRODUCTION. 



1101. In scientific as well as popular language the term indi- 

 vidual is commonlj- applied to each anrl eveiy plant ; but if by 

 individual is meant an organism incapable of subdivision with- 

 out loss of its identitj-, the term as applied thus to the higher 

 plants is obviouslj' a misnomer. It has been shown both in Vol- 

 ume I. of this series,^ and in Fart I. of the present volume,^ that 

 under certain circumstances an}' of the higher plants may be 

 separated into parts, each of which may afterwards lead an inde- 

 pendent existence. Thus buds maj- be severed from the parent 

 plant and soon establish themselves as independent organisms, 

 capable of increase in size, and becoming sooner or later dis- 

 tinguishable in no wise from the stock from which they came. 

 But there are serious difficulties in the way of regarding these 

 separable buds as true individuals : ' each bud is the promise of 

 a branch, and consists of parts which, under certain conditions, 

 may be separated from each otlier. In fact, the vegetable indi- 

 vidual is not reached in such mechanical subdivision until we 

 come to the cells of which all the parts are composed. Nor do 

 these satisfy completely the definition of an individual, since in 

 exceptional cases the cell itself may spontaneoush' divide into 

 viable parts.* 



1102. In plants, individuality is more or less completely merged 

 in community. Under normal conditions the separable parts, 

 while still attached to their common stock, co-operate for the 

 common good. If separated under favorable conditions they 

 in their turn become stocks in which are combined congeries of 

 similar separable parts, or, in other words, become individual 

 plants, in the ordinary acceptation of the term. For instance, 

 the tuber of the potato, which is the thickened extremity of an 

 underground branch, possesses a certai'n number of buds, each 



■ 1 Page 31(j. 2 Pages 152, 162. ^ Volume i. p. 316. 



* Such a phenomenon is seen in the formation of swarm-spores (or zoogo- 

 nidia) from a terminal cell of Achlya. 



