CH. XL] TWO OBJECTIONS CONSIDERED. 41 



more than seventy species there discovered, the gradation al 

 arrangement of forms was so strongly marked, that the great 

 palaeontologist, M. Gaudry, became a convert to Mr. Darwin s 

 theory in the course of the search. 1 Eeferring for many 

 more such examples to the last edition of Sir Charles Lyell s 

 &quot; Principles of Geology,&quot; let me further observe that there 

 has as yet been but little search for fossils save in Europe 

 and North America, and even these areas have by no means 

 been thoroughly explored. Concerning South America much 

 less is known, and the greater portions of Asia, Africa, and 

 Australia a.re just so much terra incognita to the palseon- 

 tologist. As M. Gaudry observes, a few strokes of the pick 

 axe at the foot of Mount Pentelikos have revealed to us the 

 closest connecting links between forms which seemed before 

 very widely separated : far closer will such links be drawn 

 when a considerable portion of the earth s surface shall have 

 been thoroughly investigated. 



The argument from &quot;missing links,&quot; therefore, in so far 

 as it has any validity at all, is an argument which rests en 

 tirely upon negative evidence. But negative evidence, as 

 everyone knows, is a very unsafe basis for argument. 2 A 



1 We may also profitably consider the toxodon, found by Mr. Darwin in 

 South America, which is &quot; one of the strangest animals ever discovered. In 

 size it equalled an elephant or megatherium, but the structure of its teeth, as 

 Mr. Owen states, proves indisputably that it was intimately related to the 

 Gnawers, the order which at the present day includes most of the smallest 

 quadrupeds : in many details it is allied to the pachydermata : judging from 

 the position of its eyes, ears, and nostrils, it was probably aquatic, like the 

 dugong and manatee, to which it is also allied. How wonderfully,&quot; says 

 Mr. Darwin, &quot; are ilie different orders, at the present time so well separated, 

 blended together in different points of the structure of the toxodon !&quot; 

 Darwin, Voyage of the Beagle, p. 82. Compare the remarks on the quaternary 

 fnnna of Western Europe in Sir John Lubbock s Prehistoric Times, 2nd 

 edition, pp. 296-298. 



3 &quot;For instance, the several species of the chthamalinae (a sub-family of 

 sessile cirrhipeds) coat the rocks all over the world in infinite numbers : they 

 are all strictly littoral, with the exception of a single Mediterranean species, 

 which inhabits deep water, and this has been found fossil in Sicily, whereas 

 not one other species has hitherto been found in any tertiary formation : yet 

 it is known that the genus chthamalus existed during the Chalk period.&quot; 

 Darwin, Origin of Species, 6th edit, p. 271. 



