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dream of answering it off-hand. It may be partially true or 
not, but the evidence at present available cannot be con- 
sidered as warranting a verdict that will satisfy everybody. 
The solution, if solution there be, must lie in the fossil-bearing 
strata. If the record of those strata be accepted as hopelessly 
imperfect, it seems almost useless even to discuss a problem 
for which sufficient data are wanting. But it may be ques- 
tioned whether the geological record can fairly be considered 
as uniformly imperfect,—at any rate, to such an extent as to. 
preclude any inferences for or against Evolution. Itis from 
this point of view that I propose briefly to set before the 
Institute the facts of Fossil Botany in their bearing upon the 
Theory of Descent. 
2. Divisions of the Vegetable Kingdom.—But before entering 
upon the subject it will be useful briefly to indicate the prin- 
ciples upon which the larger groups or sub-kingdoms of the 
vegetable world are constituted. It would be rash to take 
for granted any general acquaintance with the subject, as 
Botany has always had less attraction for the outside public 
than her zoological sister; and this assertion may be extended 
to Fossil Botany. The extinct races of plants have no sur- 
prises for the untrained eye so great as the monstrous Icthyo- 
saur or the weird Pterodactyl, no series of forms so splendid 
as the long array of Ammonites and KEncrinites. Some 
acquaintance with insignificant plants still living is required 
before the mind grasps the meaning of Club-mosses and 
Horse-tails, which reached the stature of forest trees, or 
understands that in their way they are as surprising as 
the giant Sloth or the Mastodon. 
Plants are divided, in the first place, into two vast series, 
those with and those without flowers,—Phanerogams and 
Cryptogams. Old and obvious as is this distinction, it 1s 
eminently natural. Not only does it still hold good, but 1s, if 
possible, only brought out into stronger relief by our merease 
of knowledge. A wide gulf still yawns between the seed- 
bearing Phanerogam and the spore-producing Cryptogam. 
The assertion that it is at all affected by modern research is at 
variance with obvious facts. True seeds, containing an embryo 
plant with rudimentary axis and appendages, are strictly con- 
fined to Phanerogams, and are exclusively the result of the 
fertilisation of ovules by pollen-grains through the immediate 
agency of the air. On the other hand, fertilisation, properly 
so called, in Cryptogams invariably demands the presence of 
water, and never results in a seed. Again, the asexual spore 
so frequent in Cryptogams is totally absent from Phanerogams; 
in the fern, for instance, itis the antherozoids of the prothallus 
VOL. XIX. N 
