TRANSACTIONS OF SECTION K. — PRESIDENTIAL ADDRESS. 701 



Section K.— BOTANY. 

 Prrsidknt of ttir Section: — Professor W. H. Lang, F.R.S. 



WEDNESDAY, SEPT EM BEE 8. 



The President delivered the following Address : — • 



Since I am not a visitor to our place of meeting it is my privilege to extend 

 to the members of this Section a special welcome on behalf of our Botanical 

 Department. 



The war has diminished for the time the number of those engaged in 

 botanical work. I shall not attempt any mention of those botanists who are 

 serving with the Forces, are assisting in the training of recruits, or are other- 

 wise playing their parts in the service of the country. Some have been 

 wounded, but, we rejoice to know, recovered. We have, however, to express 

 our sorrow, tempered with pride, at the cutting short of the promising botanical 

 careers of Mr. Laidlaw and jNIr. Lee, who have been killed at the Front. 



While we have no group of foreign guests, as at the last Manchester meeting, 

 we owe to the war the presence of a distinguished Belgian botanist. Professor 

 Julius MacLeod, and shall hear some of the results of investigations he has 

 made while in England. In welcoming him to this meeting we hope that he 

 may soon be able to return to his own Univer.^ity of Ghent when the invaders 

 are expelled from his country. 



Phyletic and Causal Morpliology. 



I propose to deal with some aspects of the study of plant-morphology. In 

 doing so I shall not accept any definition of morphology that would separate it 

 artificially from other departments of botany. I i-egard the aim of plant- 

 morphology as the study and scientific explanation of the form, structure, and 

 development of plants. This abandons any sharp separation of morphology and 

 physiology and claims for morphology a wider scope than has b^een customary 

 for the past fifty years. During this period the problem of morphology has 

 been recognised ae being 'a purely historical one,' 'perfectly distinct from any 

 of the questions with which physiology has to do,' its aim being 'to reconstruct 

 the evolutionary tree.' The limitation of the purpose of morphological study, 

 expressed in these phrases from the admirable addresses delivered to this Section 

 by Dr. Scott and Professor Bower some twenty years ago, was due to the 

 influence of the theory of descent. I fully recognise the interest of the phyletic 

 ideal, but am unable to regard it as the exclusive, or perhaps as the most impor- 

 tant, object of morphological investigation. To accept the limitation of 

 (norphology to genealogical problems is inconsistent with the progress of this 

 branch of study before the acceptance of the theory of descent, and leaves out 

 many of the most important problems that were raised and studied by the 

 earlier morphologists. 



