THE GEOLOGIST. 
OCTOBER, 1859. 
THE COMMON FOSSILS OF THE BRITISH ROCKS. 
Bv S. J. Mackie, F.G.S., F.S.A. 
(Continued from page 355.) 
CiiA?. 5. — First Traces of the Succession of Life. — The Lower Silurian 
Hochs. 
For the Vegetable Kingdom it is impossible to give any list composed 
with the same degree of elaboration as has been attained in the 
classification of animals. Modern plants arc, it is true, as well 
kno^^^l and as correctly grouped as modern animal life-forms ; but 
om' knowledge of fossil botany is not at all equal to our knowledge 
of fossil animals. The most minute divisions as well as the most 
important of botanical classifications are dependent upon the more 
fully developed and most perishable parts of vegetable organisms — 
the flowers and the fruits or seeds. Of these the foi-mer, the most 
essential of all, have rarely indeed, if ever, been preserved. One or 
two doubtful instances have been stated ; but these have been by 
others disputed as being only incipient buds or leaflets, or as 
accidental appearances, and the investigator of the extinct forms 
of the vegetable creations of past geological ages has, at the best, to 
infer from the remains of leaves, branches, or stems, usually more or 
less decayed, the probable class to which the originals — often, 
indeed generally, of very different structures and organic characters 
from his existing types — belong. Not uncommonly, indeed, his only 
guides are vague and indefinite resemblances of form. Still, how- 
ever, if it be essential for the attainment of a knowledge of the exact 
concatenation of past events in the sixcccssion of organic life on our 
VOL. II. 1 1 
