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We do not say that most of the genera are Huropean, but in 
each island there are some genera identical with those of 
Europe. Our imaginary traveller would at once know the 
species of Ranwnculus from their leaves, flowers, fruit, and 
general habit. He would find Cardamine hirsuta, var. sub- 
 carnosa, only differing from our common hairy Bitter Cress, to 
be found on any old walls, by its very fleshy leaves. He 
would see a Geranium (microphyllum), extremely like our G. 
lucidum, two or three kinds of Hpilobiwm or willow-herb, two 
_ lovely kinds of scorpion-grass (Myosotis), all of which would 
be familiar to him in a moment as new forms of well-known 
types. 
It does not require a botanist to detect them: any sharp, 
country-bred lad would say in a moment, “This is a butter- 
cup, that is codlins-and-cream” (the provincial name of 
Hpilobium), and so on. It would be wearisome to go through 
all the Huropean genera that thus reappear in Antarctic lands. 
I will briefly add two barberries, a ragwort, a cudweed, our 
own dandelion identical in species, lovely gentians, a butter- 
wort in the Falkland Islands scarcely to be distinguished from 
Pinguicula lusitanica, our own pale butterwort, a great many 
grasses, some ferns, very many mosses, fungi, and algze. 
This is merely introduced as a single instance of a pheno- 
menon that must be taken into account, the extension of many 
genera through widely-separated areas, and their astonishing 
constancy to their type. Let this fact be remembered as well 
as those of the variability of species. We have, in reality, 
two series of facts in living nature, some pointing to change 
and some to persistence, and our task is to reconcile them. It 
is certainly singular that often where the species are most 
unsatisfactory, as in the willows, the genus is, on the contrary, 
eminently natural; and, as we know in this case, it is also a 
very ancient one, descended from the chalk. Again, where 
the genera are intricate, the order is wonderfully natural, as 
in the Umbellifere and Composite. However, enough, perhaps, 
has been said about this subject, and we will proceed to the 
Chalk flora. 
7. Cretaceous Flora. — We have already spoken of the 
antiquity of the genera of dicotyledonous trees which first 
occur in these beds. We will now confine ourselves to one 
single point,—their abrupt appearance. It is generally ad- 
mitted that, as far as our knowledge goes, the Dicotyledons 
emerge suddenly in the upper chalk, without any previous 
hint of them in the preceding Jurassic beds, which were 
especially rich in eycads and ferns, and they occur, moreover, 
as representatives of the three great divisions,—Apetale, 
