as indicated in the Results of Geognosy. 115 
groups) however remotely connected in geographical position, 
contain the same petrifactions, it becomes necessary to state, 
that such an opinion is unsupported by observation, and incon- 
sistent with the laws which at present influence the distribution 
of animals. There is no proof of the same fossil species being 
found in the same formation at the equator, and in temperate 
and cold regions ; and when genera only are referred to, the 
reasoning becomes exceedingly vague, and apt to mislead. 
The celebrated Von Buch, a pupil of Werner, in his Travels 
through Norway, gives us an example of the Wernerian rule, 
by stating, that Orthoceratites characterise exclusively the tran- 
sition limestone formation. There is, however, no evidence,' 
that the species of Orthoceratites were here considered, nor that 
those which occur in the transition limestones of Norway, Ger- 
many, and Ireland, have been investigated with the view of de- 
termining the particular species : and I have demonstrated that 
the rule does not hold true, in reference to the genus , by the 
publication of figures and descriptions of ten species of Ortho- 
ceratites, from the beds of the independent coal formation. Un- 
til geologists form more accurate notions with regard to fossil 
species , no reliance can be placed on the observations which 
they offer respecting their geographical distribution, 
We have no reason to doubt, that the laws which now regu- 
late the geographical distribution of animals and plants, did ex- 
ercise their influence at the period when the transition and flcetz- 
rocks were forming. We may, accordingly, expect to find the 
fossil animals and plants of the temperate regions, differing as 
milch from those in tropical countries, as the recent kinds are 
known to do. Each region may be expected to exhibit a pecu- 
liar fossil Fauna and Flora. 
In reference to this view of the subject, we may add, that the 
laws which regulate the distribution of recent animals, have been, 
in a great measure, deduced from observations on those which 
inhabit the countries between the Tropic of Cancer and the 
Arctic Circle ; so that we have much to learn with regard 
to the characters of those which dwell between the Antarctic 
Circle and the Tropic of Capricorn. But the observations on 
the distribution of the fossil species, from having been chiefly 
carried on in the middle and south of Europe, are more con- 
