PRESENT TENDENCIES OF MORPHOLOGY 261 



raised to the rank of natural history, a title of honor which they 

 have borne for a long time, but which they merit only in our day. 

 If these same sciences still are often designated, and that even 

 officially as descriptive natural sciences in contrast with the ex- 

 planatory sciences, this proves that a false idea exists even at 

 present of their true significance. Since the natural system of 

 organisms is regarded as the expression of their genealogical tree, 

 taxonomy, so dry in its descriptions, makes a most vital place in 

 the history of the genealogy of classes and of species." l 



A still more important consequence resulted from these new 

 conceptions. The theory of descent introduced into the biological 

 sciences a unity of view, a community of end, which established 

 among them the closest relations of mutual dependence and sup- 

 pressed all futile questions of supremacy or of precedence. Indeed, 

 whatever were the methods employed, deduction or induction, ob- 

 servation or experiment, anatomy, physiology, ethnology, geonomy, 

 taxonomy, paleontology, all these parts of a whole thenceforth 

 indivisible should tend to the realization of the same programme: 

 to retrace in a manner as exact and as complete as possible the 

 history of the manifestations of life upon our planet, while leaving 

 to the metaphysicians and to the poets the business of seeking the 

 earliest origins or of celebrating the finalities. 



A hasty glance will permit us to appreciate what results have 

 already been obtained by this concourse of converging efforts and 

 what hopes we may conceive for the future, when, extending its 

 frontiers, biology shall benefit by the progress of science, with 

 which thus far it has had only too distant relations. Thus, while 

 the old branches of morphology rejuvenated and vivified will cover 

 themselves with a new foliation, we shall see develop about her 

 new branches swollen with an abundant and vigorous sap: cytology, 

 promorphology, tectology, experimental morphology (or the crea- 

 tion of forms by the action of primary factors), genesiology, bio- 

 metry, etc. 



But the very fact of the direct dependence of these different parts 

 of the science, their mutual interferences, the complex of causes 

 which have presided at their birth and over their evolution, fre- 

 quently render this exposition difficult and at times perhaps ob- 

 scure. 



I may be permitted to excuse myself in advance and to claim 

 all the indulgence of my audience if I have not always succeeded 

 in finding the lucidus ordo that the Latin poet claims. You will 

 kindly excuse me also for often having given a dogmatic and aphor- 



1 E. Haeckol, The Theory of Evolution in its Relations with Natural Philosophy, 

 Congress of German Naturalists in Munich (Revue Scientifique, December 8, 

 1877, p. 531). 



