THE ANIMATE WORLD A UNITY. 531 



THE ANIMATE WORLD A UNITY. 



By M. ALBEET GAUDEY. - 



THE aspect of paleontology has greatly changed since the time 

 of Cuvier, when species were supposed to be fixed, and the 

 curious monsters whose remains were unearthed from time to time 

 were believed to be unchangeable, isolated entities. Now it is 

 shown that fossil species are not thus independent, but are simply 

 phases of development of types which are carrying on their evo- 

 lution through the immensity of the ages. A plan has ruled in 

 the vast and magnificent history of this evolution, and I purpose 

 to tell what I believe I have discovered of it. I can not conceal 

 that in the present state of science such an essay will be very im- 

 perfect. When I Avas traveling in the East I found the horizons 

 in the morning veiled by the bluish mist which the poets are 

 so fond of, and tried to discover the silhouettes of the beautiful 

 marble mountains through them. So, in the morning of our 

 paleontological science, we look upon the distances of life vaguely 

 sketched, and try to distinguish a few lines of the plan that rules 

 it. We discern but little, but that little is enough to charm us, 

 as a glimpse of sunshine charms in a dark landscape. 



It seems to me, further, that besides its philosophical interest, 

 the inquiry into the plan of creation is of importance in practical 

 geology. Up to this time the determination of the age of the 

 earth has been empirical. It will become rational as soon as we 

 are in possession of the plan of creation. Geologists will recog- 

 nize that one of the best means of fixing the age of a formation 

 is to know the stage of development of the fossils it contains. 



The world of life is a grand unity, of which we can follow the 

 development as we do that of an individual. When we follow 

 the course of the immensity of geological times, we meet succes- 

 sive changes, and our mind goes on from surprise to surprise. 

 Each epoch has its own physiognomy, and each phase of each 

 epoch offers some variation ; the days of the world follow one 

 another and are not alike. Yet manifest as are the differences, 

 they are not radical. Paleontology has not discovered any new 

 branching or any new class or subclass. 



From the primary ages, animated nature has had general traits 

 of resemblance with existing nature. Sponges and polyps were 

 already forming colonies, echinoderms were divided into five parts, 

 insects were provided with three pairs of legs, arachnids had four, 

 and myriapods had a multitude. M. Bernard Renault found in a 

 coal bed an ostracode, the body of which is entirely preserved. 

 A study of it made by M. Charles Brongniart showed the same 

 details of organization as in our days. Numerous brachiopods 



