1867.] Sir Charles Lxjell and Modern Geology. 15 



Now to what conclusion does the sum of the evidence at present 

 in our possession point? It cannot be denied that, as regards 

 animals, the Protozoa are those of which we have the earliest evi- 

 dence, in the Eozoon Canadense of the Laurentian rocks, if that 

 primaeval fossil be of organic origin. Whether the Coelenterata, 

 Echinoderniata, Mollusca, or Crustacea first appeared we have no 

 evidence to show, as it is extremely improbable that the Eozoon 

 was the solitary inhabitant of the seas during the Laurentian period. 

 Known facts are in favour of the Annulosa appearing before either 

 of the other great groups ; whereas, according to the successive 

 development theory, they ought to have appeared in the order in 

 which they have been mentioned. But this evidence is purely 

 negative, and therefore of little or no value. As regards the Ver- 

 tebrata it is certain that we are cognizant of Fishes older than any 

 Amphibia, and these again are older than any known Reptiles. The 

 oldest true Reptile is probably Triassic, and thus older than either 

 Birds or Mammals ; but with regard to the order of appearance of 

 these two classes, we meet with the same difficulty as before. Now the 

 Vertebrata as a whole form a group of equal value with the Mollusca, 

 Annulosa, &c, and should consequently be compared as a whole 

 with the latter, not, as is usual, in four or five separate groups. 

 From this point of view we should find that the present state of our 

 knowledge lends very little countenance to the theory of uniform 

 progression of animal life in time ; and if we base our comparison 

 on groups of smaller value the general result is much the same; 

 for, as was shown by Professor Huxley, " if the known geological 

 record is to be regarded as even any considerable fragment of the 

 whole, it is inconceivable that any theory of a necessarily progressive 

 development can stand, for the numerous families and orders cited 

 afford no trace of such a process."* Nevertheless Sir Charles Lyell 

 remarks, " It would be an easy task to multiply objections to the 

 theory now under consideration ; but from this I refrain, as I regard 

 it not only as a useful, but rather, in the present state of science, as 

 an indispensable hypothesis, and one which, though destined here- 

 after to undergo many and great modifications, will never be 

 overthrown."! 



This conviction was probably produced by the necessity which 

 Sir Charles Lyell felt of abandoning his old opposition to the theory 

 of the transmutation of species after caret ally weighing Mr. Darwin's 

 theory of Natural Selection. Sir Charles Lyell appears to think that 

 there is a necessary and direct connection between these theories; 

 but, on our part, we cannot see why a naturalist may not be an 

 advocate for " descent with modification," and still refuse to accept 

 the theory of progressive development. It is therefore rather sur- 

 prising to read in the concluding sentences of Chapter XX. of the 



* ' Ann. Address Gool. Soo.,' 1802. f 'Antiquity of Man.' p. 405. 



