^84, ' Baron Humboldt on the Laws wlmch are observed 
The increase toward the north is owing to the Juncese and 
Cyperace^ being very rare compared with the other Phaeno- 
gamous plants, in the temperate and torrid zones. On com- 
paring the species belonging to the three families, we find that 
the Gramine^, the Cyperaceae, and the Junceae, are under the 
tropics, as 25, 7, 1 ; in the temperate region of the Old Conti- 
nent, as 7, 5, 1 ; in the polar circle, as 2f, 1. In Lapland 
the Gramineae and Cyperaceae are equal; toward the equator 
the Cyperaceae and J unceae diminish much more than the Gra- 
mineae ; the junceal form disappears almost entirely under the 
tropics, {Nova Gen. vol. i. p. 240.). 
JuNCE.® alone. =:Trop., Temp., Frig., 
(Germany, ; France, /g.) 
Cyperace^ alone. =Trop. America, nearly ; Western 
Africa, ; India, Holland, {Congo^ p. 9). 
Temp,, probably (Germany, ; France, according to 
the works of M. Decandolle, ; Denmark, Frig. J. 
This is the proportion found in Lapland, and as far as Kamt- 
schatka. 
Gra^ine^ alone. Trop. I have allowed as much as 
Mr Brown found in Western Africa, ; in India, {Con- 
go, p. 41.) M. Hornemann fixed this pm't of Africa at 
{De Indole Plant Guineensium, 1819, p. 10.) Temp. Ger- 
France, Frig. 
C0MP0SIT.E. Qn blending the plants of the plains with those 
of the mountains, we have found in equinoctial America | and 
^ ; but, of 534 Compositse of our herbaries, there are only 94 
which grow to 500 toises above the plains, (the height at which 
the mean temperature is still 21°.8 ; equal to that of Cairo, of 
Algiers, and of the Island of Madeira.) From the equatorial 
plains to 1000 toises of height (where we have still the mean 
temperature of Naples), we have collected 265 Comppsita?. 
This last result gives the proportion of Compositfe, in the re- 
gions of equinoctial Anterica, beneath 1000 toises, from J to 
This result is very remarkable, because it proves, that between 
