S Transactions. — Misceltaneous. 



One of the first difficulties that suggests itself in the consideration of 

 this particular dogma, this narrow zone to which organic life had to 

 withdraw in post-pliocene times — is that during this epoch, which it 

 appears was subsequent to, if not coincident with, the time when 

 men first commenced to talk sense in Lemuria — i.e., 100,000 years ago — 

 although the circulation of the equatorial currents must have ceased, the 

 chilled waters from both polar regions continued their course with in- 

 creased force, until they had invaded all submarine depths, and all forms 

 of organic life unable to adapt themselves to the change, or unable to reach 

 the place of refuge, perished. 



It would be difficult, however, to prove that polar marine currents have 

 ever operated over greater areas or with more force than they do to-day, 

 and frost now stretches its rigid winding sheet over tracts of land not long 

 since, geologically speaking, teeming with animal life and covered with 

 luxuriant vegetation, whilst in the same latitudes it has relaxed its grasp 

 over others which for ages had been locked in its stern embrace. 



Ever varying m their direction during the lapse of years, mighty ocean 

 streams have borne along then islands of ice loaded with the debris of rocks 

 from glaciated regions, strewing the ocean floor as liberally now as in any 

 previous era, dro]Dping boulders to-day upon beds being laid down at the 

 bottom of the sea, to be the chalk hills of future continents, and at still 

 greater abysmal depths of red clay (both composed of exuvi^ of minute 

 organisms, falling to the bottom incessantly through countless centuries ; a 

 discovery the more astonishing when it is considered that this lifeless red 

 clay, identically the same as that of the dry land so familiar to us, and so 

 long a profound mystery, is seemingly chiefly derived from the insoluble 

 residue of these Foramini/era, which is estimated at about only two per 

 cent.) changing the climates of adjacent lands, and causing ever varying 

 migrations of their fauna and flora, as well as of the life beneath the waters, 

 in all time past. 



The glaciers in present elevated regions, the Cordilleras of South 

 America and New Zealand, the Himalayas, the Alps, the Caucasus, may 

 not be greater than those which descended from the lofty mountains, higher 

 perhaps than any of these that rose above the plams covered with the 

 forests of the carboniferous era. 



Under the pluvial conditions which then probably obtained, judging 

 from the climates in which analogous vegetation flourishes at the present 

 time, we may conclude they are not. At all events the marks of ice-action 

 are to be seen, proving that in those days, as well as in our own, certain 

 portions of the earth's surface had their share of giaciation, however much 

 the general aspect of the fauna and flora may suggest that the temperature 



