FLORA. 221 



really in the north that we find the cradle of this genus 

 also. There, after their birth, the Sequoias multiplied 

 themselves, and after a first diffusion of their cretaceous 

 species, the tertiary polar flora shows us, under forms 

 differing little from the preceding, that these spread 

 themselves in their turn, and invaded the whole northern 

 hemisphere, until the time when there began to be a 

 definite decline of the group. It is known that in our 

 days there do not exist any other indigenous Sequoia than 

 those of California, represented by two species reduced to 

 a most restricted area of habitation, the last vestiges of a 

 long train of forms and of subtypes.' 



Similar details are given in regard to representatives of 

 the several orders of pines, firs, cypresses, and poplars 

 found there in the lower cretaceous deposits; and in a 

 similar way are treated remains found in the upper 

 deposits, including a genus Dewalquea, which represents in 

 a prototypic state the Hellebores of the present. And 

 having given details of specimens found in Bohemia and 

 found in Dacota and Kansas, he goes on to say : 



1 If we transport ourselves into Greenland at the epoch 

 of the upper chalk, and look upon the collection of 

 dicotyledons, passing over the more uncertain forms, we 

 see that this large class comprises everywhere the poplars 

 with leathery leaves, Populus Bergreni and P. Byperborea, 

 Heer ; the Ficus, the fruit of which has been recognised, 

 and the leaves of which were thick; the galeworts, the 

 magnoliads, the Credneria, the arales, the diospyrads, the 

 rnyrtaseas (niyrtophyllum), and lastly, the leguminosae. 

 One sees also that certain families inevitably reappear at 

 this epoch. Let one place himself in Bohemia, in Kansas, 

 or in Greenland, &c., and the effects of latitude, so far as 

 they make themselves appreciable, find themselves still 

 restricted within the narrowest limits. The frequency of 

 poplars, the absence of laurineae with persistent leaves, 

 and the presence of one laurineae with caducous leaves, 

 still doubtful, it is true (Sassafras arctica, Heer) such are 



