12 



We do not say that most of the genera are European, but in 

 each island there are some genera identical with those of 

 Europe. Our imaginary traveller would at once know the 

 species of Ranunculus 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 Epilobium 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 

 Epilobium}, and so on. It would be wearisome to go through 

 all the European genera that thus reappear in Antarctic lands. 

 I will briefly add two barberries, a ragwort, a cudweed, cur 

 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 algae. 



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 UmbeUiferce and Composites. 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 cycads and ferns, and they occur, moreover, 

 as representatives of the three great divisions, Apetalw, 



