GEOLOGY. 67 



Chemical Geology, Sartorius von Walterhausen's Observations on the 

 occurrence of minerals in Amygdaloid. 



As a recent example of speculations concerning Botanical Palaetio- 

 logy, I may give Dr. Hooker's views of the probable history of the 

 Flora of the Pacific. 



In speculating upon this question, Dr. Hooker is led to the discus- 

 sion of geological doctrines concerning the former continuity of tracts of 

 land which are now separate, the elevation of low lands into mountain 

 ranges in the course of ages, and the like. We have already seen, in the 

 speculations of the late lamented Edward Forbes, (see Book xviii. chap, 

 vi. of this History,) an example of a hypothesis propounded to account 

 for the existing Flora of England : a hypothesis, namely, of a former 

 Connexion of the West of the British Isles with Portugal, of the Alps 

 of Scotland with those of Scandinavia, and of the plains of East Anglia 

 with those of Holland. In like manner Dr. Hooker says (p. xxi.) that 

 he was led to speculate on the possibility of the plants of the Southern 

 Ocean being the remains of a Flora that had once spread over a larger 

 and more continuous tract of land than now exists in the ocean ; and 

 that the peculiar Antarctic genera and species may be the vestiges of a 

 Flora characterized by the predominance of plants which are now scat- 

 tered throughout the Southern islands. He conceives this hypothesis 

 to be greatly supported by the observations and reasonings of Mr. Dar- 

 win, tending to show that such risings and sinkings are in active pro- 

 gress over large portions of the continents and islands of the Southern 

 hemisphere: and by the speculations of Sir C. Lyell respecting the 

 influence of climate on the migrations of plants and animals, and the 

 influence of geological changes upon climate. 



In Zoology I may notice (following Mr. Owen) 2 recent discoveries of 

 the remains of the animals which come nearest to man in their struc- 

 ture. At the time of Cuvier's death, in 1832, no evidence had been 

 obtained of fossil Quadruniana ; and he supposed that these, as well as 

 Bimana, were of very recent introduction. Soon after, in the oldest 

 (eocene) tertiary deposits of Suffolk, remains were found proving the 

 existence of a monkey of the genus Macacus. In the Himalayan ter- 

 tiaries were found petrified bones of a Semnopithecus; in Brazil, remains 

 of an extinct platyrhine monkey of great size ; and lastly, in the mid- 

 dle tertiary series of the South of France, was discovered a fragment of 

 the jaw of the long-armed ape (Hylobates). But no fossil human 



Brit. Asso. 1854, p. 112. 



