2 THE STRUCTUKE OF FLOWERS. 



Systematic botanists, however, have hitherto invariably 

 contented themselves with observing differences of structure 

 only; and paid little or no attention to the "why" and the 

 " wherefore " of the differences they seized upon as being 

 more or less important for the purpose of distinguishing 

 species. When, however, the desirability of a more thorough 

 knowledge of the origin of parts of plants as interpreting mor- 

 phological characters was felt, developmental history began 

 to be studied ; a method strongly insisted upon by Schleiden, 

 for example ; and the most elaborate result of this method of 

 investigation is undoubtedly Payer's Trait e d' Org anogenie Com- 

 parSe de la Fleur, published in 1857: but if it be thought 

 sufficient to limit the study of flowers to tracing their mor- 

 phological development alone, one soon begins to see that it 

 is far from being so, and, taken by itself, it may lead one into 

 false interpretations, so that to the study of development 

 must be added that of anatomy. To Ph. van Tieghem we 

 are indebted for an elaborate treatise, entitled RecJierclies sur 

 la Structure du Pifitil et sur V Anatomee Coniparee de la Fleur 

 (1871), dealing with the more minute details of floral struc- 

 tures. This treatise, however, still leaves much to be 

 desired. 



Besides these methods, analogy and especially teratology 

 furnish assistance of no mean value. Here we are especially 

 indebted to Dr. M. T. Masters for his standard work on 

 Teratology ,^ 



Now, any one of these methods taken alone would be 

 insufficient, and in many cases would be far from thoroughly 

 accounting for particular points under consideration. 



Hence to arrive at a complete interpretation of the origin 

 of every sort of structure to be found in floAvers, it can only 



* A Gerinan edition, Pflanzen Teratologic, ed. Tainmer, 1886, has 

 Euraerous additions. 



