July 14, 1905.] 



SCIENCE. 



45 



to experimental questioning, to physiology. 

 Indeed, one may say that morphology is 

 that which is not yet understood physiolog- 

 ically. The separation of the different 

 tasks of botany is not in the nature of 

 things proper, but is only a preliminary 

 means at first to orientate ourselves with 

 reference to the maze of phenomena. The 

 barriers between these tasks must then in 

 the nature of the case fall with further 

 progress. I do not wish to deny the 

 value of phylogenetic investigation, but 

 the results w^hich it has brought forth 

 resemble more the product of creative 

 poetic imagination than that of exact 

 study, i. e., study capable of proof. If 

 the knowledge of the historical develop- 

 ment of plant forms hovers before us 

 as an ideal, we shall approach it only 

 when we attack the old problems of mor- 

 phology, not simply with the old method, 

 that of comparison, but experimentally, 

 and when we regard as the basal problem 

 of morphology not phylogenetic develop- 

 ment, but the essence of development in a 

 large sense. Even if we had the story of 

 development spread out clearly before us, 

 we could not content ourselves wath the 

 simple determination of the same ; for then 

 we should be constrained to ask ourselves, 

 how it has been brought about. But this 

 question brings us straight back to the pres-- 

 ent, to the problem of individual develop- 

 ment. For there is for natural science 

 hardly a more significant word than this of 

 Goethe's: 'was nicht mehr entsteht, konnen 

 wir uns als entstehend nicht denken. Das 

 Entstandene begreifen wir nicht.' It is 

 then the task of modern morphology to 

 learn more exactly the factors upon which 

 at this time the origin of structures de- 

 pends. To this task, for which there was 

 at that time but little preparatory work 

 consisting of a few important attempts by 

 the gifted Thomas Knight, Wilhelm Hof- 

 meister, who is known to most of us only 



as a comparative morphologist, did a too 

 little recognized service. For he pointed 

 out, even before this trend of study became 

 apparent in zoology, that the ill-designated 

 'Entwickelungsmechanik' pursues essen- 

 tially the same goal as the causal morphol- 

 ogy of botany. 



We may regard as a motto this sentence 

 from Hof meister 's 'allgemeiner Morphol- 

 ogic ' : ' es ist ein Bediirfnis des mensch- 

 lichen Geistes, eine Vorstellung sich zu 

 bilden fiber die Bedingungen der Form- 

 gestaltung wachsender Organismen im all- 

 gemeinen.' This is even now the problem 

 of present day morphology. Comparative 

 consideration, including, of course, the es- 

 pecially important history of development, 

 offers us valuable preparation for the in- 

 tellectual grasp of the problem, but, above 

 all, for the pursuit of the experimental 

 method. 



That the zoologists also have felt this 

 necessity to strike out into new ways be- 

 sides that of comparative morphological 

 observation shows anew that for all organ- 

 isms the problems are really the same. Let 

 us then take for our watchword develop- 

 ment, not only as a problem, but also for- 

 the methods with which we seek to bring- 

 ourselves nearer its solution. ...... 



SCIENTIFIC BOOKS. 

 Eesearch Metliods in Ecology. By Frederic 



E. Clements, Ph.D. Lincoln, Nebraska, 



The University Publishing Company. 1905, 



Pp. xvii + 334. 



This work by Professor Clements is intended 

 by the author as a handbook for investigators 

 and for advanced students of ecology, and not 

 as a text-book of the subject. It, therefore, 

 contains a somewhat elaborate account of 

 methods used by the author in his studies of 

 the last eight years during which a serious at- 

 tempt has been made by him to discover and 

 to correlate the fundamental points of view in 

 the vast field of vegetation. 



The book is presented in four chapters or 



