98 Mr. H. H. Howorth on 



ponding to the glacial phenomena so conspicuous in the 

 northern one, and this fact is fatal to such theories as Dr. 

 Croll's, which are based upon the recurrence of similar 

 conditions in either hemisphere alternately. The only evi- 

 dence we have from the southern hemisphere, and of that 

 there is abundance, goes to show that local glaciers were 

 then developed on a much larger scale than now, and 

 coexisted alongside of a similar vegetation now prevailing, 

 proving anything but a critical change of climate. 



Again, the evidence of the local geologists is almost, 

 if not quite unanimous that these glaciers were the 

 immediate precursors of the present ones, and that 

 neither the remains of the fauna, nor the loose deposits, 

 justify any other conclusion than that the great develop- 

 ment of the southern glaciers was contemporaneous and 

 did not alternate with the great development of the northern 

 glaciers, and neither preceded nor was subsequent to it. 



On this point Agassiz is very emphatic — 



" I have not noticed anything to confirm the idea that 

 the glaciers of the northern hemisphere have alternated with 

 those of the southern hemisphere in their greatest extension, 

 as is assumed by those who connect with the precession of 

 the equinoxes, the difference of temperature required for 

 the change. The abrasions of the rocks seemed to me 

 neither more nor less fresh in one hemisphere than in the 

 other ; nor do the veins of molten rocks rising above the 

 surrounding disintegrating rocks stand out in a more or less 

 bold relief in either case. However astronomical causes 

 may have been connected with the climatic conditions of 

 the world, I see no reason for believing, from any facts I 

 have observed, that alternations of temperature in the 

 northern and southern hemispheres have ever been the 

 primary and efficient causes of glacial phenomena." {Nature, 

 vol. VI., p. 272.) 



Mr. Belt says : " I think it highly probable that the 



