NOVEMBEK 11, 1904.] 



SCIENCE. 



619 



bered that the earlier botanists were either 

 ecclesiastically trained or not trained at 

 all, and to them it was entirely satisfying 

 to explain all metamorphoses upon teleo- 

 logical grounds. It is a matter of great 

 surprise, however, to note how this point 

 of view is still maintained by some investi- 

 gators who have abandoned the doctrine of 

 types, and in every other respect are inha- 

 ling a modern atmosphere. 



One serious result of belief in the doc- 

 trine of types was the use of the most com- 

 plex structures to explain the simpler ones ; 

 the reading of complexity into simplicity. 

 For example, the type flower selected was 

 one that had become completely differen- 

 tiated ; in short, a highly organized flower. 

 This was read into all simpler flowers, and 

 was even carried over the boundary of 

 angiosperms and applied among gymno- 

 sperms, to the utter confusion of terminol- 

 ogy and understanding. Fortunately for 

 the students of cryptogams, a great gulf 

 was thought to be fixed between plants 

 with seeds and those without, and this the 

 flower did not cross. 



It is safe to say that this phase of mor- 

 phology, with its types, and teleology, and 

 simplification of complex structures, is now 

 in its decline. 



2. THE PHASE OE THE STEUCTUEE OF THE 

 DEVELOPING OEGAN. 



This tj^e of morphology has chiefly 

 characterized the period under considera- 

 tion. Its fundamental conception is evolu- 

 tion; its purpose is to discover phylogeny; 

 and its method is based upon the belief 

 that ontogeny recapitulates phylogeny. As 

 a consequence, there was developed for the 

 first time what may be called a philosophy 

 of the plant kingdom, organizing the de- 

 tails of morphology into one coherent whole 

 about such central facts as alternation of 

 generations and heterospory. Study of the 

 metamorphoses of plant organs was re- 



placed by a study of their development and 

 of 'life-histories,' and the earliest stages 

 of gametophyte and sporophyte and repro- 

 ductive organs were scrutinized and re- 

 corded in the greatest detail in the search 

 for relationships. Shifting its center of 

 gravity from the mature organ to the nas- 

 cent organ, morphology departed very far 

 from special taxonomy, while at the same 

 time it was laying the solid foundation for 

 general taxonomy. The reversal of old 

 ideas was conspicuous, and much of the 

 old terminology was found to be false in 

 suggestion and almost impossible to shake 

 off. For example, it has been a constant 

 surprise to me to see the persistent use of a 

 sex terminology in connection with flowers 

 by those who must know better, and who 

 must know also that they are helping to 

 perpetuate a radical misconception. 



A still more important result of this 

 change of front in the morphological attack 

 was the necessary reversal of the method of 

 interpretation. No longer was the flower 

 of highly organized angiosperms read down 

 into the structures of the lower groups ; but 

 from the simplest beginnings structures 

 were traced through increasing complexity 

 and seen to end in the flower, explaining 

 what it is. This meant that evolution had 

 replaced the old idea of types and meta- 

 moi-phosis, and was building facts into a 

 structure rather than cataloguing them. 

 This spirit of modern morphology has not 

 as yet dominated instruction. Its facts are 

 developed in all their detail, abundantly 

 and skilfully, but very seldom do the facts 

 seem to be coordinated. The old spirit of 

 accumulating unrelated material still dom- 

 inates teaching, and crams the memory 

 M'ithout developing permanent tissue. 



The detailed developmental study of 

 plants and their organs gave rise to what 

 has been called morphological cytology, but 

 it is an unfortunate differentiation, for 

 cytology merely pushes the search for 



