XXXIV INTRODUCTION. 



been already said to prove that there is no intrinsic 

 difference between the laws of growth in the two 

 cases. As our knowledge increases we shall be 

 enabled to ascertain approximately of what extent 

 of variation a given form is capable, under given con- 

 ditions, and to refer all formations now considered 

 anomalous to a few well-defined forms. Already 

 teratology has done much towards showing the 

 erroneous nature of many morphological statements 

 that still pass current in our text-books, though their 

 fallacy has been demonstrated again and again. Thus 

 organs are said to be fused which were never separate, 

 disjunctions and separations are assigned to parts that 

 were never joined, adhesions and cohesions are spoken 

 of in cases where, from the nature of things, neither 

 adhesion nor cohesion could have existed. Some organs 

 are said to be atrophied which were never larger and 

 more fully developed than they now are, and so on. 

 So long as these expressions are used in a merely 

 conventional sense and for purposes of artificial classi- 

 fication or convenience, well and good, but let us not 

 delude ourselves that we are thus contributing to 

 the philosophical study either of the conformation 

 of plants or of the afl&nities existing between them. 

 ^Vhat hope is there that we shall ever gain clear con- 

 ceptions as to the former, as long as we tie ourselves 

 down to formulas which are the expressions of facts as 

 they appear to be, rather than as they really are ? 

 Wliat chance is there of our attaining to comprehensive 

 and accurate views of the genealogy and affinities of 

 plants as long as we are restricted by false notions as 

 to the conformation and mutual relation of their parts ?' 



It is probable that many terms and expressions calculated to mislead 



