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ANIMAL PEDIGREES. 
May, 1891. 
Quaternary and 
Recent. 
Pleiocene. 
Meiocene. 
Eocene. 
Cretaceous. 
The animals, and for that matter the plants too, of the 
Meiocene age, did not come into existence irrespective of 
pre-existing animals and plants, but were the direct lineal 
descendants of the Eocene animals and plants; and the 
forefathers of those of Pleiocene and Recent times. 
Kainozoic. 
# # * * Mesozoic. 
Palaeozoic. 
So, too, were the animals of Mesozoic times the children 
of those of the Palaeozoic age, and the parents of the 
Kainozoic fauna. 
And so this idea of continuity of life from its earliest 
dawn on the earth, through age after age, down to the present 
time, forces itself upon us : an idea involving the further 
conception of the evolution of existing animals from unlike 
ancestors of former times : an idea constraining us to admit 
that animals, like men, have pedigrees, and that between 
the animals of all ages a kinship, a blood relationship, 
exists. 
The recognition of this kinship is the determining 
feature of the Natural History of to-day. The reconstruction 
of these pedigrees is the great work of the future : the 
rewriting of the past histories, not merely of one or two 
groups for a limited number of generations, but of all animals 
and for all time:—a formidable, but an entrancing, problem; and 
whatever misgivings I may have as to my power of presenting 
it aright, no apology is needed for asking your attention to a 
consideration of the means at our disposal for attacking it, of 
the evidence on which we rely in our attempts to reconstruct 
the past histories, to determine the pedigrees of animals. 
