THE CARBONIFEROUS PERIOD. 
79 
growth is complete, but rolled up at first, like 
Fern-leaves before they expand. Their fruit re- 
sembles somewhat the Pine- Apple. 
The mode of growth of the Conifer as recalls a 
feature of the Equisetaceas also, in the tufts of 
little leaves which appear in whorls at regular in- 
tervals along the length of the stem in proportion 
as it elongates, reminding one of the articulations 
on the stem of the Equisetacese. The first cone 
also appears on the summit of the stem, like the 
terminal cone in the Equisetacese and the Club- 
Mosses. Thus in certain types of the vegetable, 
as well as the animal creation of earlier times, 
there was a combination of features, afterwards 
divided and presented in separate groups. In 
the present times, no one of these families of 
plants overlaps the others, but each has a distinct 
individual character of its own. 
At the close of the middle geological ages and 
the opening of the Tertiary periods, the Monoco- 
tyledons become abundant, the first plants with 
flower and enclosed seed, though with no true 
floral envelope ; but not until the two last epochs 
of the Tertiary age do we find in any number the 
Dicotyledonous plants, in which flower and fruit 
rise to their highest perfection, dlius there has 
been a procession of plants, from their earliest in- 
troduction to the present day, corresponding to 
their botanical rank as they now exist, so that the 
