PLANT ARCHEOLOGY. 275 



Upon the data in hand, now much extended, and on the 

 supposition that the same species of tree had not appreciably 

 altered meanwhile in its relations to temperature, Heer long 

 ago elaborately compared the miocene climates with those of 

 our time, and Saporta corroborates his conclusions. For the 

 northern regions the difference is said to be equivalent to 25 

 or 30 degrees of latitude — that is, we have now, say in Eu- 

 rope, in latitude 40° and 45°, and in Atlantic America, in 

 latitude 38° to 40°, the temperature and the vegetation which 

 then flourished at latitude 70° in Greenland. Grinnell Land, 

 in latitude 82°, only two hundred leagues from the pole, had 

 a forest of coniferous trees ; among them — associated with a 

 Poplar-tree, a Hazel, and a Birch — was the Silver Fir of 

 Europe, and the Bald Cypress of the swamps of the southern 

 United States. The same combination, minus the Cypress, 

 must now be sought in the more elevated parts of central and 

 southern Germany. The Sequoias and Magnolias and Per- 

 simmons of Greenland, in latitude 70°, mingled with Maples, 

 Oaks, and Grapevines, have their representatives partly in 

 Virginia and on the Ohio River, partly in California. The 

 miocene of the southern shore of the Baltic had Laurels, Ole- 

 anders, and Camphor-trees, but no Palms, so far as is known, 

 thus answering to the Mediterranean flora, but miocene Palms 

 reached to Belgium and Bohemia ; and Provence, on similar 

 data, had then about the climate of the coast of Zanzibar. 



Another conclusion which Saporta confidently reaches — 

 and which indeed is reached from all sides — is that of a very 

 moist quaternary climate. Looking back to this compara- 

 tively recent period from our own, everywhere the streams 

 have dwindled. Through great river-beds shrunken stream- 

 lets now meander in insignificant channels ; springs reach the 

 surface much lower down the valleys than of old ; and the 

 " rivers without water " of Egypt and Syria, and the reduced 

 level of the Dead Sea, are so many evidences of a dryness 

 supervening upon a general humidity greatly in excess of the 

 present. These fuller watercourses of themselves indicate a 

 more temperate or mean climate, a more equal distribution of 

 heat and cold through the year. Was this equable climate 



