FLORULA HONGKONGENSIS. $91 3 
tremely interesting, in regard to its vegetable geography, is its ex- 
treme inequality of surface, producing often the greatest differences of 
climate, at very short distances ; all the changes, from the most scorch- 
ing tropical lowland, to the region of perpetual snow, may be experienced 
within one single day’s journey. To note down the influence, which 
these different conditions exercise on such a large genus as the Oak, 
would be very instructive to the botanist. 
It is inexpedient to treat of the production of Oaks of Mexico as a 
whole; the best plan will be to divide the species into groups, accord- 
ing to the elevation at which they occur. When it is considered, that 
Oaks are found in Mexico, from the level of the ocean, to a height of 
12,000 feet, and to an amount at least of eighty known species, notwith- — 
standing that only one-half of its area has been investigated, it may be - 
easily understood, that such a division becomes necessary; although, 
on the other hand, the theme is too manifold, to admit of being ex- 
hausted in this place. Nor is this, perhaps, required, since our sole 
object is to exhibit, in large features, the geographical relations of a 
tribe of plants in one part of thé world, by explaining the changes 
which its species undergo from the north to the south, from the lowland 
to high localities. I deem it most suitable, therefore, to consider the 
Mexican Oaks as they exhibit themselves to the traveller, who proceeds 
right aeross from the eastern coast westward, until he descends on the 
opposite side, to the shores of the South Sea; which route will carry 
him across the loftiest mountains of the country. 
(To be continued.) — 
Fioruta HowakowGENsis: an Enumeration of the Plants collected 
in (he Island of Hong-Kong, by Major J. G. Champion, 954% Reg., 
the determinations revised and the new species described by GEORGE 
BENTHAM, Esa. 
: (Continued from p. 805.) 
AQUIFOLIACEÆ*. 
ce 1. Ilex cinerea, Champ., sp. n.; glabra, ramulis ol angulatis, 
foliis brevissime petiolatis oblongis paucidentatis basi obtusis sub- 
* Omitted among Polypetale, where it might have been better placed next to 
Celastraceæ, although gamopetalous. —— 
