PART III. 



ALTERATIONS OF POSITION. 



Necessarily connected with changes in the arrange- 

 ment of organs are similar alterations in their position ; 

 so closely, indeed, that but for convenience sake, it 

 would be unnecessary to treat them separately. There 

 are, however, some anomalous developments affecting 

 the relative position of organs that could hardly be 

 treated of under any of the preceding paragraphs. 

 There are, also, certain rare instances where an organ 

 is not so much displaced as misplaced ; that is to say, 

 it is developed on or from a portion of the plant, which 

 under usual circumstances does not produce such an 

 organ. In the former instance, the altered position is 

 due to or coexistent with other changes ^ but in the 

 latter case the new growth may spring from organs 

 otherwise in nowise different from ordinary. The word 

 Displacement is here used to signify the unusual posi- 

 tion of an organ ; while Heterotaxy may serve to in- 

 clude those cases where a new growth makes its 

 appearance in an unwonted situation, as, for instance, 

 a leaf-bud on a root, &c. ProHfication is also included 

 under this heading, the unusual position of the buds 

 in these cases being of graver import than the mere 

 increase in number. Alterations in the position of 

 the sexual organs are spoken of under the head of 

 Heterogamy. 



