116 ^fr. C. Iledley on Surviving Refugees 



Its relics are detected by Prof. Hutton in an abyssal area two 

 thoupand fatlioms deep, •which only in strained language can 

 be termed a " plateau." Of where he supposes that it lay 

 Geikie * writes : '' so abruptly does the continental plateau 

 rise from the ocean trough, that a depression of the sea-level 

 or an elevation of the plateau for ten thousand feet would add 

 only a narrow belt to the Pacific coast between Alaska and 

 Cape Horn." Much of the biological and geological data on 

 which Prof. Button's paper was based have since been refuted 

 or withdrawn. 



Another answer to the question at issue is tendered by 

 Dr. H. O. Forbes t- After a lucid summary of the kinship 

 of austral life observed by earlier naturalists and of facts 

 collected by himself in the Chatliam Islands, he constructs 

 an immense hypothetical Antarctic continent to explain these 

 problems. 



The impression left on my mind by a careful study of this 

 paper is that a foundation so slender is insufficient to bear a 

 superstructure so vast. No geological era is assigned for the 

 map of Ancient Antarctica accompanying the article. To 

 this area the Mascarene Islands appear to be attached chiefly 

 upon the strength of an extinct bird of dubious lineage. The 

 difficulties of the change from the climate of primeval Ant- 

 arctica and the change in the depth of circumpolar seas are 

 not explained, or, indeed, the changes proved. The Ant- 

 arctic fauna and flora, so far as surviving fragments allow us 

 to reconstruct them, do not suggest that wealth of forms 

 which so wide an extent of land should have developed. A 

 much harsher climate would have prevailed over Forbes's 

 broad continental area than over a chain of islands or a narrow 

 strip of land. Had the conditions indicated hy Dr. Forbes 

 ■once existed, then each of the southern land-masses should have 

 preserved an equal heritage of Antarctic life^ whicli is not the 

 case. A sharing of population may not be invariably cited 

 (as it is in this paper) as indicative of former land-passages, 

 for it has been clearly demonstrated in the case of the Azores 

 and Galapagos that considerable immigration may occur 

 across wide expanses of ocean. 



Mr. H. A. Pilsbry has remarked J that "the presence of 

 very similar forms in southern South America and Tasmania 

 and New Zealand has been accounted for by the hypothesis 

 of a ibrmer more extensive Austral continent or ' Ant- 



* Address Gecigraph. Sect. British Association, 1892, p. 796. 

 t "The Chatham Islands, their relation to a former Southern Con- 

 tinent," vol. iii. Supplementary Papei's, Royal Geographical Society, 1893. 

 I ' Guide to the Study of Helices,' p. xxxix (Philadelphia, 1805). 



