66 Royal Institution :— ‘ 
Palestine would then be East African. Afterwards the glacial 
inroad would destroy the mass of preexisting life, excepting the few 
species most tenacious of existence, which survive in the still com- 
paratively warm depression of the Jordan valley, which thus became 
a tropical ‘outlier,”’ analogous to the boreal marine outliers of our 
own seas. The Indian types are explained by the former continuous 
miocene continent from India to Africa. The peculiar species may 
either yet be found in Arabia, or, if not, may be descendants of 
species which inhabited the country with a limited range, or may be 
variations stereotyped by isolation. 
The peculiar fishes of the Jordan are most important, dating 
probably from the earliest period after the elevation of the land. 
The genera of the peculiar species are exclusively African, while the 
Species are representative rather than identical. We may explain 
this by the miocene chain of freshwater lakes, extending from Galilee 
to the Nyanza, Nyassa, and Zambesi, when an ichthyological fauna 
was developed suited to the warm conditions that prevailed, part of 
which survives in the Jordan. 
During the glacial period Lebanon must have been similar in 
temperature to the present Alps, as the existing mammals and birds 
on the summits are identical with those of the Pyrenees and the 
Alps; not so the glacial flora, of which almost every trace has been 
lost. But the flora had not the same powers of vertical migration 
with the fauna, of which, however, the Elk, Red Deer, and Reindeer, 
found in the bone-caverns, have long since perished. 
During the present period the Mediterranean forms have over- 
spread the whole country, excepting the mountain-tops at an eleva- 
tion of 9000 feet and the Jordan depression. These two exceptions 
can be best explained by the fact that the traces of the glacial road 
are not yet wholly obliterated, and that the preceding warm period 
has left its yet stronger mark in the unique tropical “outlier’’ of the 
Dead-Sea basin, analogous to the boreal outliers of our mountain- 
tops, the concave depression in the one being the complement of the 
convex elevation in the other. 
ROYAL INSTITUTION OF GREAT BRITAIN, 
February 7, 1868. 
“Qn the Animals which are most nearly intermediate between 
Birds and Reptiles.” By Professor Huxrey, LL.D., F.R.S. 
Those who hold the doctrine of Evolution (and I am one of them) 
conceive that there are grounds for believing that the world, with all 
that is in it and on it, did not come into existence in the condition in 
which we now see it, nor in anything approaching that condition. 
On the contrary, they hold that the present conformation and com- 
position of the earth’s crust, the distribution of land and water, and 
the infinitely diversified forms of animals and plants which consti- 
tute its present population, are merely the final terms in an immense 
series of changes which haye been brought about, in the course of 
