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Show GEOGRAPHICAL DISTRIBUTION, [On..LP· XI. 324 d) b t find in every great clasa was formerly suppose , u we 1 · 1 mc:any forms which some naturalists rank as geogfraplucla ' di · t · · and a host o c ose y races and others as stinc spec~es ' k d b ll t allied or repres~~tative ~or.ms which are ran e y a na-uralists a.s specifically distinct. As on the land, so in the ·waters of t~e sea,. a s1 o w southern migration of a marine fa"?-na, W~lCh dur1ng the Pliocene or even a somewhat. earher :penod, was n~~rly ·.[! nn along the continuous shores of the Polar Cncle, un·nuo account on the theory of mo dI'f ic at 1' on, 1.[! 0r many cl~sely allied' forn1~ now living in areas completely sun-d d Thus I think we can understand the presence of Inearen y. existinO, ' and te' rtiary representati·v e .1[! orms on. the eastern and .:estern shores of temperate North Amer1~a ; d the still more striking case of mai~Y closely allied ~~ustaceans (as described in Dana's admn·a~le .work), of some fish and other Inarine animals, in the Mediterranean and in the seas of J apan,--areas now separat~d by a continent and by nearly a .hemi~phe~e of eq.uato:Ial ocean .. These cases of relationship, Without 1de~tity, of the Inhabitants of seas now disjoined, and likewise of the past and present inhabitants of the temperate lands of North America and Europe, are inexplicable on the theory of creation. We cannot say that . they hav~ ?een crea:ted alike, in correspondence with the nearly similar .physical conditions of the areas ; for if we compare, for Instanc~, certain parts of South An1erica with th~ southern continents of the Old World, we see countnes cl?sely c?r;esponding in all the~r vh¥sical conditions, but With thmr Ill-habitants utterly diSSimtlar. . . But we must return to our more immediate s~bJ~ct, the Glacial period. I am convinced that Forbess Vl~W may be largely extended. In Europe we have the plainest evidence of the cold period, from the western shores of Britain to the Oural range, and southward to the Pyrenees. We may infer, frorn the frozen. mn:mmals ~n~ nature of the mountain vegetation, that Sibena was Sl~Ilarly affected. Along the Himalaya, at po.ints 900 mll~ apart glaciers have left the marks of thmr . former l.o desce~t; and in Sikkim, Dr. Hooker saw maize grow1ng OBAP. XI.] DURING THE GLACIAL PERIOD. 325 on gigantic ~ncient _moraines. South of the equator, we have some duect evidence of former glacial action in New Zealan~; a~d t~e ~arne plants, found on widely separated roountam~ In this Island, tell the same story. If one account whiCh has been published can be trusted we have direct evidenc~ of glacial action in the south-e;stern corner of Austraha. Looking to America; in the northern half ice-borne fragments of rock have been observed on the e~stern side as far south as lat. 36°-37°, and on the shores of the Pacific, where the climate is now so different as far south as lat. 46° ; errati~ boulders have, also, be~n noticed on the rocky mountains. In the Cordillera of Equatorial South America, glaciers once extended far below their pres.ent level. In central Chile I was astonished at the str:ucture of .a vast mound of detritus, about 800 feet in height, crossing a valley of the Andes · and this I now fe~l ~onvince.d was a gigantic moraine, left far below any ex1stlng glacier. Further south on both sides of the continent, from lat. 41 o to the southernmost extremity we have the clearest evidence of former glacial actio~ in huge boulders transported far from their parent sourc~. . We do not know that the Glacial epoch was strictly s~ultaneous at these several far·distant points on opposite sides of the world. But we have good evidence in almost every ~ase, tha~ the epoch was included within the latest geolo~lCal period. We have, also, excellent evidence, that It endured for an enormous time as measured by hears, at each point. The cold may have come on or ave ceased, earlier at one point of the globe than at 'another_, but seeing that it endured for long at each, and that It was contemporaneous in a geological sense it seems to me probable that it was, during a part at' least of ~~ period, actually simultaneous throughout the world. 1 Itliout s?me distinct evidence to the contrary, we may at east admit as probable that the glacial action was simul~ ane?us on the eastern and western sides of North AmerIca, m the Cordillera under the equator and under the warmer teJ?perate zones, and ·on both sides of the southern extremity of the continent. If this be admitted, it is |