208 MAMMALS. 



seem to have proved that the habitat of the I3aljENA mysticetus is, and has ahvaj's been, exchi- 

 sively confined to the Polar Seas, and that it has therefore no claim to a place in the European 

 fauna. It would appear, however, from Von Baer's account of the mammals inhabiting the seas 

 of Nova Zcmbla, that the "Whale is not found there. The right "VVliales of the North Atlantic, 

 formerly chased by the Basque Whalers, belonged, according to Eschricht, to a species B. Biscay- 

 anus Eschricht, which has more affinity to the right Whale of the Southern hemisiDhere. At 

 all events, it has the characters which Mr. Flower uses as generic to distinguish the Southern 

 right "Whale from the mysticetxts. Whether a similar double series of species exists in the 

 Southern hemisphere, is not known, but there is some indication that it maj', for Dr. Gray 

 has described a second Southern species, B. antifodarum, from New Zealand. Which of these 

 Southerners, B. australis or B. antipodarum, is the more Antarctic, or whether there is one more 

 Polar than the other, is not known. 



The occui-rence in the opposite Polar regions of species so closel}' allied, and whose consti- 

 tutions are similarly adapted for life in the coldest regions of the earth, and apparently incomjjatiblo 

 with a residence in warmer latitudes, is a suggestive fact, which may throw some light upon 

 a much-disputed point, regarding the glacial epoch ; viz. whether the cold of that period was a 

 local refrigeration confined to the north, and due to the pecidiar distribution of land and water, 

 or to some cosmical cause, affecting only the northern hemisphere ; or whether it was a general 

 diminution of heat affecting the whole earth, and to be ascribed to some more imiversal cause. 

 There is plenty of proof that the glacial ice did not extend over the whole earth. Dr. Falconer 

 says, we have distinct proof that the glacial refrigeration which characterised the Alpine valleys, 

 and plains of Europe north of the Alps, was greatly modified in intensity on the southern side 

 of the chain. The enormous glacier of the Yalley of the Adige, after emerging from the ' Lago 

 di Garda,' melted away, leaving on the margin of the Valley of the Po a vast mass of moraine. 

 On the southern side of the Apennines, glacial phenomena have nowhere as yet been traced down 

 upon the plains on their flanks.* 



The glacial phenomena in North America come to an equally abrupt termination before they 

 reach the Gulf of Mexico, and from the general uniformity of the line of termination, and other 

 circumstances, there is reason to think that at the time when the glaciers, which have so left their 

 mark, were in existence, thej^ ran into the sea as the ice now does on the coasts of Greenland, which 

 may be a reason why no marks of glacial action are now found south of what may have been the 

 old line of coast. These facts, I believe, to be due to the greatest part of these southern plains in 

 Europe, and the whole of them in America, having been under water during the most part of the 

 glacial ejDOch ; but I do not the less arrive at the same conclusion as Dr. Falconer that the Arctic 

 Circle did not come much farther south than the seas which covered Italy in Europe, and Georgia 

 in North America ; and that the cold was, as it should have been, less intense in the tropics than 

 nearer the poles. 



We can hardly expect that evidences of glacial action similar to those left in the northern 

 hemisphere should be found in the southern, because all tlie land nearer the Pole than the latitudes 

 where in the north the action ceased, viz. (Italy in. Europe, and Georgia in America, in other words, 

 35° and 45° North hit.) was there imder water, except New Zealand and Tiei-ra del Fuego, and il 

 is precisely in these lands that glacial cold has been ascertained to exist — marks of its action ha\'ing 



* Palconer, iu "Nat. Hist. P.ov.," Jau. 1863, p. 111. 



