PRESENT TENDENCIES OF MORPHOLOGY 263 



The works of specification have a higher end, a r61e not only of 

 description but also of prediction and origination; they rise a step 

 in the scale of human knowledge. Their interest then becomes much 

 more important. 



And this interest is not limited to the science of beings actually 

 living, it extends to the study of extinct forms hidden, in a petrified 

 state, in the depths of the earth. 



Paleontology opens before us as a gigantic collection of archives, 

 and despite the regrettable gaps which the future undoubtedly 

 will more and more fill up, it furnishes us the most precious docu- 

 ments for the retracing of the ancestral lines of plants, of animals, 

 and of man himself. Veritable medailles de la creation, the fossils 

 enable us to reconstruct upon firm foundations the natural history 

 of living beings in the exact sense of the word by methods analogous 

 to those that brought into use history, properly so-called, as the 

 sociologists and philosophers understand it. 



From this moment paleontology forms with zoology an indis- 

 soluble whole and these two divisions of morphology reciprocally 

 furnish cooperation. But zoology is incomplete. Despite the efforts 

 of generations which preceded us we are still far from knowing all 

 the living beings which actually exist on the surface of the earth. 

 Paleontology has given us only very rare indications, if we consider 

 the great number of organisms which have disappeared without 

 leaving permanent traces (protoplasmic beings which lack a skele- 

 ton or which have a slightly resistant skeleton, etc.), especially if 

 we think of the difficult and rarely realized conditions which were 

 necessary to assure the fossilization and the preservation of animals 

 through all the vicissitudes of the earth's surface. Many of these 

 gaps in the morphological series are in course of disappearing or will 

 disappear little by little, thanks to the more effective methods of 

 investigation which we possess, thanks also to the progress of phys- 

 ical geography and to the more intensive study of the countries 

 thus far unexplored. 



Geonomy, or the study of geographical distribution, also, is 

 greatly illuminated and simplified by the doctrines of transforma- 

 tion. The actual distribution of animals and plants should no longer 

 be considered as the result of chance or of a directive principle which 

 replaces the old creations by new ones just as one sees the scene 

 change in the theatre each time the curtain rises. 



A causal connection exists between the past and the present. 

 Paleontology indicates to us those portions of the earth in which 

 we should seek forms with archaic characters, and geonomy in turn 

 enables us to divine the changes of the earth's surface and reveals 

 to us the distant causes for the suppression of animals which have 

 already disappeared. 



