of the Arctic and the Antarctic Faunas. 313 



Further, tliu supporters ot' the tlieory of tlie peruiaucucy of 

 climatic tauuas must reuiouibor that it is phiiuly irreconcil- 

 able with the modern doctrine of evolution. If the individual 

 climatic faunas had developed each for itself from the very 

 beginning of the world, tho typos, wherever arising, could 

 never have spread over the whole earth ; each faunistic region 

 would have had its own phylogom.'tic history from the oldest 

 pre-Cambrian times till now. This, however, docs not accord 

 with any paltcontological picture whatever, nor with that 

 aflbrdcd by recent zoology and botany. 



"We have hitherto based the theory of the universal cha- 

 racter of the Early Tertiary fauna on palajontological data, 

 and on the relations of that fauna to the present tropical surface- 

 water fauna. We now come to a third consideration. 



BiPOLARITY. 

 Nearly all authors who have worked at the fauna of the 

 higher southern latitudes speak of the great "habit-resem- 

 blance " of this fauna to that of the higher northern latitudes. 

 This likeness is, however, impaired by the fact that the 

 South- American and Australian faunas send their southern 

 stiagglers into these regions; further, the extraordinarily 

 slight development of circumpolarity renders the presentment 

 of a complete picture of the fauna as a zonally disposed whole 

 extremely difficult ; and, lastly, we know nothino- of the 

 fauna of the real antarctic. 



In the year 1890 I attempted a sketch of the surface-water 

 fauna of the higher soutiiern latitudes compared with that of 

 the higher northern latitudes, which, apart from the errors 

 and inaccuracies involved in statistics of that nature, presents 

 a fairly complete picture of the scientific data at that time for 

 it is based on the collected literature and on the works of 

 authoritative writers. 



This work brings out two points which are of essential 

 importance in judging of the resemblances — first, the resem- 

 blances in the various divisions of the animal kingdom are 

 very unequally expressed, being in some cases quite sur- 

 prising and in others hardly noticeable; secondly, even the 

 absence of many families and geuera distributed over the 

 warmer seas contributes to increase the habit-resemblance of 

 the two faunas of the higher latitudes. For the theory we 

 are now occujjied with, that all the climatic faunas have arisen 

 from a separaling-out of the Early Tertiary or i)re-Tertiary 

 fauna — that is, through a kind of selection— a negative 

 resemblance is quite as important as a positive one, thou"-h it 

 is less evident. 



