The science of life : fully illustrated in tone and line and including many diagrams

THE EVIDENCE

which, while progressive in respect of seedevolution, remained primitive in its general fern-like form and growth. But if the true link between ferns and seed plants must be sought in some type ancestral to both modern ferns and seed-ferns, none the less the seed-ferns decrease the gap (Fig. 130). Once more, examples could be multiplied ;

OF THE ROCKS

but these suffice, since all we are concerned with here is to show that missing links turn up in the most diverse groups of animals and plants, and from all periods of the earth’s long history. Steadily the gaps are filled and the ramifications of the tree of life mapped out with ever-increasing confidence and precision.

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