524 



SCIENCE. 



[N. S. Vol. XX. No. 512. 



of these three methods, since all of them 

 are needed for the investigation of his prob- 

 lems. No less must we demand that he has 

 a firm grasp of the general results of the 

 anthropological method as applied by vari- 

 ous sciences. It alone will give his work 

 that historic perspective Avhich constitutes 

 its higher scientific value. 



A last word as to the value that the an- 

 thropological method is assuming in the 

 general system of our culture and educa- 

 tion. I do not wish to refer to its prac- 

 tical value to those who have to deal with 

 foreign races or with national questions. 

 Of greater educational importance is its 

 power to make us understand the roots 

 from which our civilization has sprung, 

 that it impresses us with the relative value 

 of all forms of culture, and thus serves as 

 a cheek to an exaggerated valuation of the 

 standpoint of our own period, which we 

 are only too liable to consider the ultimate 

 goal of human evolution, thus depriving 

 ourselves of the benefits to be gained from 

 the teachings of other cultures and hinder- 

 ing an objective criticism of our own work. 



Feanz Boas. 



PLANT UORPnOLOGY* 

 Those who organized these congresses left 

 to the guests whom they honored with their 

 invitation a high degree of freedom in the 

 handling of their si;bject. In the exercise 

 of that freedom, which I gratefully ac- 

 knowledge, I have decided not to attempt 

 any general dissertation on the present 

 position of plant morphology as a whole, 

 but to discuss certain topics only in the 

 morphology of plants, which at present 

 take a prominent place in that branch of 

 the science of botany. These center round 

 the question of the relation of the axisto 

 the leaf in vascular plants. 



* Address delivered at the International Con- 

 gress of Arts and Science, St. Louis, September, 

 1904. The full text will be published in the 

 official proceedings. 



We may, I think, date the foundation of 

 a scientific comparative morphology of 

 plants from the publication of the 'Ver- 

 gleichende Untersuchungen ' of Hof meister, ■ 

 and his recognition of the fundamental 

 homologies between mosses, ferns and other 

 plants. But notwithstanding the sound- 

 ness of Hof meister 's comparisons for the 

 alternating generations as a whole, the 

 homologies of the parts remained unsatis- 

 factory; the chief reason for this was that 

 their grouping was not derived from the 

 comparison of nearly allied species; nor 

 does it seem to have been held as important 

 to consider critically whether such parts as 

 were grouped together were or were not 

 comparable as regards their descent. For 

 long years after the publication of the 

 'Origin of Species' homology had no evolu- 

 tionary significance in the practise of plant 

 morphology. But in the sister science of 

 zoology this matter was taken up by Ray 

 Lankester, in 1870, in his paper 'On the 

 Use of the Term Homology in Modern 

 Zoology, and the Distinction Between 

 Homogenetic and Homoplastic Agree- 

 ments.' (Many botanists of the present 

 day would be the better for a careful study 

 of that essay.) He pointed out that the 

 term homology, as then used by zoologists, 

 belonged to the Platonic school, and in- 

 volved reference to an ideal type. This 

 meaning lay at the back of Goethe 's theory 

 of metamorphosis in plants, and it seems 

 to have been somewhat in the same sense 

 that homologies were traced by Hofmeister. 

 Lankester showed that the zoologist's use 

 of the term 'homologous' included various 

 things; he suggested the introduction of a 

 new word to define strict homology by 

 descent; structures which are genetically 

 related in so far as they have a single repre- 

 sentative in a common ancestor, he styled 

 'homogeneous'; those which correspond in 

 form, but are not genetically related, he 

 termed 'homoplastic' 



