Arctic Exploration. 289 



The separation of the terrestrial lines from the truly solar 

 ones in the solar spectrum, as seen from the earth's surface, is 

 another important desideratum, inquiry into which can only 

 be well pursued in high latitudes, where the path of the sun 

 at low altitudes above the horizon gives opportunities for the 

 necessary observations not to be secured elsewhere. 



Geology. — A more complete investigation of the geology of 

 the Arctic regions is extremely desirable, both for its scientific 

 importance and the value of its practical results. The exist- 

 ence of Carboniferous, Jurassic, and Miocene rocks is known, 

 but much is needed to be done to obtain complete collections 

 of their organic remains. The existence of a true palaeozoic 

 coal formation has been determined, but we require to know 

 its extent and composition. 



One of the most interesting facts of late years acquired to 

 geological science has been that of a luxuriant and highly 

 organized vegetation, of the Miocene age, on the east coast 

 of Greenland ; a fact alluded to further on under the head of 

 Botany. It is of great importance that some determinations 

 based on fragments of leaves should be confirmed by the 

 acquisition of more perfect foliage, as well as of seeds and 

 fruits ; such materials would be of great value in illustrating 

 a flora which is in itself of much interest, but this interest is 

 vastly increased when one realizes the important inquiries 

 on which such knowledge would throw light. These inquiries 

 are: — 



1. The geographical distribution of the Miocene flora, as 



indicated by the agreements and differences between 

 the Miocene plants of Arctic regions and of Central 

 and Southern Europe. 



2. The relation of the Miocene flora to previous and sub- 



sequent vegetations, and its bearings on the present 

 geographical distribution of plants on the globe. 



3. The evidence derived from these plants as to the physical 



conditions of the globe in past geological epochs. 

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