Botany and Zoology. 233 



several years ago brought forward his doctrine of the very high 

 antiquity of our actual temperate and alpine floras, of their 

 co-existence in highly elevated regions of low latitudes even in 

 early times. So now, applying his former conclusions to the 

 southern hemisphere, and to " a period remote even in geological 

 language," he notes that " the special generic types of the antarc- 

 tic flora " " belong without exception to the great groups or nat- 

 ural orders which are now almost universally diffused throughout 

 the world ; and the ancestral types from which they originated 

 were probably carried to that region at a remote period, when the 

 physical conditions of the earth's surface were widely different 

 from those now prevailing." " Various considerations tend to the 

 conclusion that the dispersal of the chief cosmopolitan genera of 

 plants may have coincided with the period of the older secondary 

 rocks ; and at that period physical agencies far transcending those 

 of our experience prevailed throughout the earth. If the ances- 

 tors of the antarctic types of vegetation were then established in 

 a, south polar continental area, and were developed from them by 

 gradual modification, I see no difficulty in believing that they may 

 have maintained themselves through successive gradual changes 

 of physical conditions within the same region, and even that some 

 may still survive within the Antartic Circle." 



Whether or not one accepts the idea of such high geological 

 antiquity which Mr. Ball claims for what he calls Cosmopolitan 

 types, we must wholly agree with him in his use of this name for 

 them, in preference to that of Scandinavian. The latter term 

 was used by Hooker before the relation of the present flora of 

 our temperate zone to a former high-northern vegetation was made 

 olear, and before the types in question could "with more reason 

 be referred to North America than to Scandinavia." Mr. Ball's 

 remark that, as to many of them, "the balance of evidence points 

 to an original home in the high mountains of lower latitudes " 

 chimes in with his favorite and original doctrine. And this indeed 

 seems likely to gain ground the more it is considered and applied, 

 as he is applying it, to the explanation of actual distribution. 



The interesting problem is to discriminate, as well as may be, 

 the two commingled elements of the northern temperate floras, 

 one of arctic, the other of more endemic mountain origin. An 

 interesting presentation, as concerns Central Europe, is made in 

 Heer's Nival Flora of Switzerland, a posthumous work, published 

 by the Societe Helvetique des Sciences Naturelles, of which a 

 summary is given in Nature for Dec. 31. 



The following idea is extremely suggestive. " In a zoological 

 a,s well as a botanical sense Brazil is one of the most distinct and 

 separate regions of the earth. It is in large part a granitic re- 

 gion, from which vast masses of superincumbent strata have been 

 denuded, and where the granite itself has undergone a great 

 amount of decay and ablation. We there see the ruins of one of 

 the greatest mountain masses of the earth, where a very ancient 

 flora and fauna were developed, of which portions were able to 



