Miscellaneous. 377 



that numerous Tertiary species have continued down into the qua- 

 ternary, and many of them to the present time. A goodly per- 

 centage of the earlier and nearly half of the later Tertiary Mol- 

 lusca, according to Deshayes, Lyell, and, if we mistake not, Bronn, 

 still live. This identification, however, is now questioned by a 

 naturalist of the very highest authority. But, in its bearings on 

 the new theory, the point here turns not upon absolute identity so 

 much as upon close resemblance. For those who, with Agassiz, 

 doubt the specific identity in any of these cases, and those who 

 say, with Pictet, that "the later Tertiary deposits contain in ge- 

 neral the debris of species very nearly related to those which still 

 exist, belonging to the same genera, but specifically different," may 

 also agree with Pictet that the nearly related species of successive 

 faunas must or may have had " a material connexion." Now the 

 only material connexion that we have an idea of in such a case is a 

 genealogical one. And the supposition of a genealogical connexion 

 is surely not unnatural in such cases — is demonstrably the natural 

 one as respects all those Tertiary species which experienced natu- 

 ralists have pronounced to be identical with existing ones, but which 

 others now deem distinct ; for to identify the two is the same thing 

 as to conclude the one to be ancestors of the other. No doubt there 

 are differences between the Tertiary and the present individuals — 

 differences equally noted by both classes of naturalists, but differently 

 estimated. By the one these are deemed quite compatible, by 

 the other incompatible with community of origin. Bat who can 

 tell us what amount of difference is compatible with community of 

 origin ? This is the very question at issue, and one to be settled by 

 observation alone. "Who would have thought that the peach and the 

 nectarine came from one stock ? But this being proved, is it now 

 very improbable that both were derived from the almond, or from 

 some common amygdaline progenitor? Who would have thought 

 that the cabbage, cauliflower, broccoli, kale, and kohlrabi are deriva- 

 tives of one species, and rape or colza, turnip, and probably rutabaga, 

 of another species ? And who that is convinced of this can long 

 undoubtingly hold the original distinctness of turnips from cabbages 

 as an article of faith ? On scientific grounds, may not a primordial 

 cabbage or rape be assumed as the ancestor of all the cabbage races, 

 on much the same ground that we assume a common ancestry for 

 the diversified human races ? If all our breeds of cattle came from 

 one stock, why not this stock from the Aurochs, which has had all the 

 time between the diluvial and the historic periods in which to set off 

 a variation perhaps no greater than the difference between some sorts 

 of cattle ? 



That considerable differences are often discernible between Tertiary 

 individuals and their supposed descendants of the present day affords 

 no argument against Darwin's theory, as has been rashly thought, 

 but is decidedly in its favour. If the identification were so perfect 

 that no more differences were observable between the Tertiary and 

 the recent shells than between various individuals of either, then 

 Darwin's opponents, who argue the immutability of species from the 



Ann. # Mag. N. Hist. Ser. 3. Vol vi. 25 



