SECT. 1. ORGANOGRAPHY AND GLOSSOLOGY. 



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axes, may be reduced to a general mode of expres- 

 sion, by a method proposed by M. Schimper, and 

 subsequently elucidated by M. Braun. Even in those 

 cases where their distribution does not seem to be 

 regulated by any law of symmetry, this may be con- 

 sidered to be owing to the various disturbing causes 

 which are perpetually modifying the conditions under 

 which their arrangement would otherwise have taken 

 place. As the mineralogist refers the crystalline 

 forms of his minerals, to certain geometric solids, 

 whose angles at least are the same as those on the 

 crystal; so we must here neglect the accidental displace- 

 ments, produced by the unequal development of those 

 parts to which the foliaceous appendages are at- 

 tached, or some other circumstances, and look only to 

 the primary conditions upon which their distribution 

 depends. If in those cases, even, where the leaves are 

 most scattered on the plant, we were to draw a line 

 from any one which is seated lower down the stem 

 or branches, to another next above it, and so on, 

 this line will be found to follow a spiral direction ; and 

 thus we ultimately arrive at a leaf, which is seated ver- 



tically above that from which we started. The usual 

 mode of expressing this, is to name the number of the 



