GEOGRAPHICAL DISTRIBUTION. 335 
It is needless here to speculate either on the 
physical, or final causes, which produced these 
curious changes of species, in this highest order 
of the Molluscous inhabitants of the seas, during 
some of the early and the middle ages of geolo- 
gical chronology ; but the exquisite symmetry, 
beauty, and minute delicacy of structure, that 
pervade each variation of contrivance throughout 
several hundred species, leave no room to doubt 
the exercise of Design and Intelligence in their 
construction ; although we cannot always point 
out the specific uses of each minute variation, in 
the arrangement of parts fundamentally the 
same. 
The geographical distribution of Ammonites 
in the ancient world, seems to have partaken of 
that universality, we find so common in the ani- 
mals and vegetables of a former condition of our 
globe, and which differs so remarkably from 
the varied distribution that prevails among exist- 
ino; forms of oro-anic life. We find the same 
genera, and, in a few cases, the same species of 
Ammonites, in strata, apparently of the same 
age, not only throughout Europe, but also in 
distant regions of Asia, and of North and South 
America.* 
* Dr. Gerard has discovered at the elevation of sixteen thou- 
sand feet in the Himmalaya Mountains, species of Ammonites, 
e. g. A. Walcoti, and A. Communis, identical with those of the 
Lias at Whitby and Lyme Regis. He has also found in the same 
parts of the Himmalaya, several species of Belemnite, with Te- 
