GREAT STEPS IN ORGANIC EVOLUTION 907 



have preceded and prepared the present. And next they see this 

 present world and its forms of life as but in their turn dominant, 

 yet already partly fading into the past, as its rarer species disappear. 

 Yet also so far preparing the future, as its commoner forms spread 

 and vary. 



The animal palaeontologist has not a few Uving fossils, but more 

 conspicuous are the long-surviving species of the plant world. 

 Various Cycads and ferns give conspicuous examples of this, but 

 perhaps plainest of all are the survivals of the Tertiary flora upon 

 the vast heath-formations or upon their margins, over the Mediter- 

 ranean uplands, such as Pistacia lentiscus, and often also exuberant 

 in cultivation; witness walnut, pomegranate, oleander, Judas-tree, 

 laurel, and that commonest and hardiest of palms, Chamcerops 

 humilis. Most curious is the survival of Gingko biloba, now familiar 

 beyond botanic gardens, but imported from Japanese temple- 

 gardens, and not yet found in nature. 



Palaeontology has thus got far beyond that simple searching and 

 gathering, listing and classing of fossils as curious natural antiquities, 

 which is all that some still see in it. From this indispensable material 

 — fragmentary and broken though it so largely is, and still after a 

 century and more of increasing quest a woefully imperfect record, 

 and one we see no hope of completing as we would desire, since 

 practically only organisms with hard parts could bequeath us any 

 record of their existence — the past of life, even to our own, has 

 now to no small extent arisen from the dead. And this so surely, 

 so vividly, that we can now call in the painter, the modeller, or 

 sculptor to our aid, so that the great museums of palaeontology, 

 especially in America, yet increasingly in other countries as well, 

 are already becoming wonder-houses second to none. Yet even 

 these are but sketches and studies towards the museums of the 

 future, with their panoramic halls for the successive phases of the 

 past, with their long- vanished world-landscapes renewed, and each 

 with the vegetation and animal life characteristic of its time. Nor 

 will all this be a "mere popularisation" of science, but its freshening 

 aid and stimulus. For each such scene, incomplete as it still must be, 

 must stimulate more than ever the questions of all the sciences con- 

 cerned. Thus, how did this distinctive geologic scene come about? 

 How did it become peopled with these leading actors, so largely 

 new? And how did these in their turn so largely disappear? And 

 was this with or without some new type of offspring in their turn ? 

 All these questions and more will be increasingly obvious and 

 insistent; so recruiting by fresh youth the ever-thinning ranks of 

 geologists and palaeontologists, of botanists and zoologists, at once 

 evolutionists and physiologists, and sending these out as inquirers 

 anew. In 1926 the exploring expeditions, naturalistic and humanistic 

 together, were reckoned as many as two hundred; and even at an 



