"Prof, Schouw on the Geographic Distribution (^ Grasses. 13S 
than that of the extra-tropical plants. Although^ however^ the 
quotients in the torrid and temperate zones may be nearly 
equal upon the whole, when taken in subdivisions there will be 
an inequality. In the warm regions of South America, the 
grasses, under 200 toises elevation, form from 1-1 5th to 1-1 6th of 
the whole ; in the West Indies 1-1 7th; on the river Esquibo, in 
‘Zugana, l-12th to l-15th ; on the river Congo, 1-I2th to l-13th ; 
in Guyana, 1-lOth ; (in the three last the local circumstances are 
particularly favourable for the grasses) ; in the East Indies, ac- 
cording to Brown, l-12th ; in Arabia, l-15th ; and in tropical 
New Holland, 1-lOth to 1-11 th. Now, attending to the circum- 
stance, that the tropical are scarcely so well known as the other 
phaenerogamic plants, it is not improbable that the true quotient 
for the torrid zone is 1-1 0th to l-12th. In the warmer parts of the 
temperate zone, the grasses appear to form a smaller proportion 
of the vegetation ; for, in the extra-tropical parts ©f New Holland 
they form l-24th to l-25th, at the Cape l-35th, in Greece 1-1 5th 
to l-iOth, in the Canary Islands l-12th to I-13th, in the Crimea 
and Caucasus l-14th to l-15th, in Naples 1-1 1th to l-12th, in 
France 1-1 3th, in Harberg 1-Mth, and in Egypt (where, how- 
ever, the circumstances are peculiarly favourable) l-8th. Farther 
north, the relative numbers seem to rise somewhat higher; in Ger- 
many 1-1 3th, in Great Britain 1-1 1th to 1-1 2th, in Denmark 1- 10th 
to 1-1 1th, in Scandinavia 1-lOth to 1-1 1th, in Kamschatka l-7th 
to l-8th, Lapland 1-lOth, Iceland l-8th to 1 -9th, Greenland l-8th 
to l-9th, and in North America, according to Pursh, l-14th to 
1-1 5th. We may assume, perhaps, as a medium for the warmer 
parts of the temperate zone, l-12th to l-14th ; for the colder, to- 
gether with the polar regions, 1-8th to 1-1 0th. That almost in 
every Flora, the quotient is considerably higher than in the works 
of Persoon, and of Rgemer and Schultes, affords another proof, 
that, in the rule, the distribution of the grasses is more extensive 
than that of the other phsenerogamic plants. 
In Southern Europe, the number of the grasses seems to di- 
minish according to the elevation, for, in the Alpine Flora, they 
are only l-18th. The distribution according to the elevation 
does not, therefore, accord with that according to the latitude; 
in South America the agreement is greater, for the relative num- 
bers are, 0 to 200 toises, l-15th to 1-1 6th ; 200 to 1100 toises^ 
