; paereie ae oS tructural and Ph Phy silo Hat Be of fany. 
to the: winter ; whe in Tasiania fou fale at ‘all's seasons. ine oa 
~ Most of the rivers are dried up for considerable periods, ~ 
and leave gradually diminishing ‘creeks’ of water only 
where their beds are deepest. Woody savannahs termed — 
‘orass-lands,’ and thickets of bushes known as ‘scrub,’ — 
occupy the greater part of Australia so far as it has been 
opened to colonisation. ‘The grass-land is a carpet ‘ok 
meadow interspersed with occasionai forests of Eucalyptus, 
and adorned in the rainy season with numerous bulbous —_ 
plants, Liliaceze, Orchides, &c., and ‘everlastings.” The ~~ 
scrub consists entirely of densely interwoven shrubs, ~~ 
Proteacex, Epacridez, Myrtacee, Leguminose, &c., among. a 
which rise sometimes lofty trees, Eucalypti and Acacias; © 
but is destitute of herbaceous plants and grasses. In the, <3 
_ valleys of the creeks there is only a dense scrub; and here, ~~ 
among other plants, are found the Casuarinas (she-oaks), 
palms, and the grass-tree, Xanthorrhea. In addition, 
Australia has also, like the Asiatic steppe-region, grass-, “4 
salt-, and sand-steppes. c seg! 
12. The North American Forest- Ree Fgh ea a 
The regions of vegetation of North America correspond 
to those of the eastern hemisphere. A’ broad forest-zone 
passes through the whole continent from Behring’s Strait to 
Newfoundland, and southwards as far as Florida and the _ 
mouths of the Mississippi. ‘The narrow strip of coast of 
~ California may be compared with the Mediterranean region 
im its rainless summer period ; and the Asiatic steppes.cor- 
_respond to the prairies between the Sierra Nevada and_ the 
Mississippi. ere 
AS compared with the Europzo-Siberian, the Ameneaa hg 
_ forest-region is colder in the same latitude, and the difference a 
may be estimated as, on an average, one of 10° of lat. ‘Thus, — 
for example, ne ies annual are at N ew York, in 
