EESULTS OF PAL^EONTOLOGICAL RESEAKCH 47 



fins (paddles) and their hind limbs became entirely 

 useless. The tail became likewise transformed into 

 a rudder, which, indeed, is the case with the Fishes, etc. 

 Yet mammals they remain all the same, since the 

 mammalian nature is not in itself contradictory to 

 an aqueous existence ; but everything that was specially 

 adapted for a land life must be transformed to fit 

 the new water one and that only. 



Hence they converged ever more and more in ex- 

 ternal features towards the Fishes, with whom otherwise 

 they are not at all related. 



Naturally such evidence of convergence must be 

 established or rendered probable by exact comparison 

 of changes in both the converging groups. Of the 

 Whales there are lacking entirely fossil remains of any 

 kind whatever. 1 



In point of fact so far no evidence of convergence 

 has been palaeontologically determined, by which 

 even only the original generic characters have been 

 perfectly eliminated. 2 ' On the whole I think/ says 

 Deperet, ' that the evidences of convergence which 

 were asserted in connection with nearly all animal 

 groups were greatly overestimated. In the majority 



1 Steinmann (Die Geologischen Grundlagen, etc., p. 235) will not accept 

 the idea of descent of the Whales from quadrupedal ancestors. He 

 endeavours to explain their descent from definite groups of the great 

 Mesozoic Saurians. There is much to be said for his opinion, but ' very 

 convincing ' it is not. 



2 Deperet- Wegner : Die Umbildung der Tierwelt, p. 205. Professor 

 Fleischmann (Die Darivinische Theorie, Leipzig, 1903, p. 263) writes, 

 regarding the origin of the whale, a veritable satire, most delightful to read, 

 but which avoids all explanation. 



