GEOLOGICAL ANTIQUITY OF FLOWERS AND INSECTS. 
39 
vegetable remains, as everywhere revealed by the studyof geology, 
renders it very probable that we have hit upon the true order 
of appearance on our globe. Such terms as were used by the 
older geologists, as the 44 age of fish,” the 44 age of reptiles,” and 
44 age of mammals,” roughly express this method of succession. 
And beyond modifications in the hard and fast lines where they 
made these animals to come in or disappear, nothing has been 
discovered to interfere with the arrangement. Corresponding to 
this was the classification of the vegetable kingdom, based on 
fossil remains, founded by Brongniart many years ago, of the 44 age 
of acrogens ” (or ferns), 44 age of gymnosperms ” (or conifers), and 
u age of angiosperms ” (true seeding-plants). In both kingdoms, 
animal and vegetable, there is the strongest evidence — evidence 
which every new discovery strengthens — that the lower preceded 
the higher, and the general the special forms. 
Brongniart/s simple classification of the geological order of 
succession of the three most prominent of vegetable types 
upon the earth, ought not to lead the student to infer that 
during the 44 age of acrogens ” or ferns, there were no conifers, 
or that, when the 44 age of gymnosperms ” prevailed, there ex- 
isted no true seeding or angiospermous plants. The classification 
indicates only the prevailing groups of vegetation. These can 
be again divided, so that we find the order of classification 
corresponds to that of palaeontological succession. Thus up 
to the conclusion of the Silurian period, sea-weeds or cdgce were 
the dominant types of vegetation ; from the upper Silurian to 
mid-Carboniferous times, ferns and club-mosses (Lycopodiacece) 
were most abundant. In the Permian and Triassic periods 
coniferous trees were in the ascendency ; then follow monocoty- 
ledonous plants, such as palms and grasses in the Oolite, and true 
flower-bearing plants in the Lower and Upper Cretaceous ; 
with abundance of them in the Eocene, a preponderance of 
them in the Miocene strata, and so onwards to our own time. 
Even among the true flower-bearing or phanerogamous plants, 
we find that the monocotyledonous preceded the dicotyledonous ; 
whilst the wind-fertilized ( anemophilous ) groups of dico- 
tyledons appeared before the insect-fertilized ( entomophilous ), 
certainly as orderly as the Acrogens came before the Grymno- 
sperms. For the occurrence of a few insect-fertilized plants 
among the first dicotyledonous flora no more invalidates this 
conclusion than does the fact that we find coniferous trees in 
the Devonian rocks interfere with their existing in the so- 
called 44 age of acrogens.” 
It has been recently shown that the colours of petalled or 
perianthed flowers exist in the first place because they are useful 
to plants in attracting insects ; and that the visits of insects thus 
secured, cause pollen to be carried from one plant to another, 
