vered as would give countenance to the idea that one species
had ever been transformed into another. And to nearly every one this
objection seemed insuperable.

But in 1859 appeared a book which, though not dealing primarily with
paleontology, yet contained a chapter that revealed the geological
record in an altogether new light. The book was Charles Darwin's Origin
of Species, the chapter that wonderful citation of the "Imperfections of
the Geological Record." In this epoch-making chapter Darwin shows what
conditions must prevail in any given place in order that fossils shall
be formed, how unusual such conditions are, and how probable it is that
fossils once imbedded in sediment of a sea-bed will be destroyed by
metamorphosis of the rocks, or by denudation when the strata are raised
above the water-level. Add to this the fact that only small territories
of the earth have been explored geologically, he says, and it becomes
clear that the paleontological record as we now possess it shows but
a mere fragment of the past history of organisms on the earth. It is
a history "imperfectly kept and written in a changing dialect. Of this
history we possess the last volume alone, relating only to two or three
countries. Of this volume only here and there a short chapter has been
preserved, and of each page only here and there a few lines." For a
paleontologist to dogmatize from such a record would be as rash, he
thinks, as "for a naturalist to land for five minutes on a barren point
of Australia and then discuss the number and range of its productions."

This citation of observations, which when once pointed out seemed almost
self-evident, came as a revelation to the geological world. In the
clarified view now possible old facts took on a new meaning. It was
recalled that Cuvier had been obliged to establish a new order for some
of the first fossil creatures he examined, and that Buckland had noted
that the nondescript forms were intermediate in structure between
allied existing orders. More recently such intermediate forms had been
discovered over and over; so that, to name but one example, Owen had
been able, with the aid of extinct species, to "dissolve by gradations
the apparently wide interval between the pig and the camel." Owen,
moreover, had been led to speak repeatedly of the "generalized forms"
of extinct animals, and Agassiz had called them "synthetic or prophetic
types," these terms clearly implying "that such forms a