34G INCREASED NUMliEl?. 



a repetition or renewed development of organs. When 

 the increased number arises from multiplication proper, 

 or from repetition, the ordinary laws of alternation are 

 not interfered with, but if from chorisis or *' d(5double- 

 raent," it may happen that the normal an-angement is 

 disturbed. 



Without studying the mode of development, it is 

 not in all cases possible to tell under which of the 

 above categories any particular instance should be 

 placed ; hence, in the following sections, except where 

 otherwise stated, the cases are grouped according to 

 the appearance presented in the adult condition, rather 

 than to the way in which the changes from the typical 

 condition are brought about. With reference to the 

 foliar organs it is necessary to distinguish those cases 

 in w^iich there is, from any cause, an augmentation in 

 the number of component parts of a whorl, from those 

 in which the increase takes place in the numbers of the 

 whorls themselves. * , 



CHAPTER I. 



MULTIPLICATION OP AXILE ORGANS, INFLORESCENCE, ETC. 



By Linne an undue number of branches was desig- 

 nated as " plica," from the analogy with the disease of 

 the hair known as plica polonica : " Plicata dicitur 

 plantay cum arbor vel ramus excrescit "minimis intertextis 

 rammlis, tanquam plica polonica ex pilis, ceu instar nidi 

 Piece, quod vulgo a genio ortum arhitratur ; frequens 

 apud nos in Betula, prcesertim Norlandice, in Carpino 

 Scanice, nee infrequens in Pinuy^ 



By some of the older authors this condition was 

 called polyclady. In some cases, it woidd seem to 



' Phil But.,' 274. 



