12 THE SUNKEN ISLAND OP ATL.VNTlS. 
perta instruclum. Venae polymorphs^, e centro uteri n caraem radia- 
tim dispersse. Sporangia subrotunda^ echinata; sporidia dilute fuli- 
ginea/* 
THE SUNKEN ISLAND OF ATLANTIS. 
A Lecture delivered by Dr. P. Unger, Professor of 
Botany in the Vienna University.* 
Although our knowledge of the former condition of our globe, be- 
fore man took possession of his inheritance, is but a recent acquisition, 
yet it is based upon such a solid foundation, that science, having fairly 
taken wing, already ventures to deal with the most difficult problems. 
A few decades have hardly elapsed since the playing with fossils as- 
sumed a serious character, and the geological structure of the solid land 
and the condition of the sea*s bottom began to be regarded as the result 
of vast previous revolutions. If at present tbis know^ledge is still in 
many points defective, and its shortcomings require to be supported b;^ 
h}7)otheses, these should not prevent us from placing confidence in it 
and regarding it as an important scientific basis. To man as lord of tlie 
globe, it is merely a matter of precaution to take notice of the structure 
r 
of the house w^hich he inhabits, the foundation upon which it rests, 
and the materials of which it is built. What he has to hope or to fear 
may be of slight importance to the single individual, but surely it 
cannot be a matter of indifference to the whole human race, destined, 
as it would seem to be, to a more prolonged existence than is usually 
supposed. T may be permitted to sketch a brief geological period, 
L 
not to show how unsafe is the ground we tread, and how changeable 
the condition under which we live, but how vast and incalculable r 
the final effect of even the most insignificant causes — causes from the 
sway of which neither the world nor we can emancipate ourselves. 
The sketch I am going to give refers to a remote, though not to the 
remotest period of our planet, — one which, if not immediately preceding, 
at all events is very near man's appearance on earth. It has been 
named the Tertiary period, and is distinguished by its supplying us 
* Translated from Dr. Unger*s *Versunkene Inael Atlantis,' 8vo, Wien, 
1860, Braunmiiller, and transferred to our pages by the kind permission of the 
author and publisher. 
