MALFORMATIONS AND THEIR 

 SIGNIFICANCE IN ORGANOGRAPHY 



INTRODUCTION. 



MALFORMATIONS have always been a fertile theme in botanical literature. 

 Not only does every deviation from what we are accustomed to regard 

 as the fixed and therefore apparently normal excite our interest 1 , but 

 endeavours have been made to obtain through the study of malformations 

 a deeper insight into the homology of organs, and especially of the repro- 

 ductive organs in the higher plants. We must admit that the investigation 

 of malformations has been of importance in this respect ; the transforma- 

 tion of the primordia of stamens into petals, which occurs so commonly 

 in double flowers, led to the first recognition of the ' foliar ' nature of 

 the stamen. In recent times through the influence of the theory of 

 descent many malformations, and especially those which have appeared 

 to be reversions to primitive relationships of configuration, have been 

 regarded as of special value. 



The first question we have to ask is What do we mean by a mal- 

 formation? It is impossible to give a sharp definition, for we cannot 

 fix the limit where the normal ceases and the abnormal begins, and the 

 ' normal ' itself is a variable quantity. Let us take a concrete example. 

 Anemone Hepatica has usually six perianth-leaves in its flowers, but the 

 number varies. In seventy-five flowers taken at random the following 

 were the numbers of the perianth-leaves : in thirty-five there were six, 

 in twenty-nine there were seven, in ten there were eight, in one there 

 were nine, and in four of the flowers examined there were intermediate 

 formations between perianth-leaves and stamens. The indication here is 



1 It is a frequent experience that people who have not the slightest interest in the normal form of 

 the organs of plants will bring one a malformation because it is ' so interesting.' 

 GOEBKL N 



