RECORDS DESTROYED BY FIRE. s 
the new territory, in the struggle for life, abundant oppor- 
tunity of developing themselves peculiarly, and of forming 
new species. This formation of new species has evidently 
taken place pre-eminently during these intermediate 
periods, of which, unfortunately, no petrifactions could 
be preserved, whereas, on the contrary, during the slow 
sinking of the ground there was more chance of nume- 
rous species dying out, and of a retrogression into 
fewer specific forms. The intermediate forms between the 
old and the newly-forming species must also have lived 
during the periods of elevation, and consequently could 
likewise leave no fossil remains. 
In addition to the great and deplorable gaps in the pale- 
ontological records of creation—which are caused by the 
periods of elevation—there are, unfortunately, many other 
circumstances which immensely diminish their value. I 
must mention here especially the metamorphic state of the 
most ancient formations, of those strata which contain the 
remains of the most ancient flora and fauna, the original 
forms of all subsequent organisms, and which, therefore, 
would be of especial interest. It is just these rocks—and, 
indeed, the greater part of the primordial, or archilithic 
strata, almost the whole of the Laurentian, and a large part 
of the Cambrian systems—which no longer contain any 
recognizable remains, and for the simple reason that these 
strata have been subsequently changed or metamorphosed 
by the influence of the fiery fluid interior of the earth. 
These deepest neptunic strata of the crust have been com- 
pletely changed from their original condition by the heat 
of the glowing nucleus of the earth, and have assumed 
a crystalline state. In this process, however, the form of 
