NIGER EXPÉDITION. 139 
= 
In many of their physical features, they form a continuation 
of the great Sahara desert; that mysterious blank on our 
maps, upon whose sea of sand so many of our venturesome 
countrymen have embarked, to be heard of no more. The 
hitherto unexplored mountains rise 8000 feet and upwards 
above the sea, in serried ridges and isolated peaks, promising 
a rich harvest to some Botanist, who may in these higher 
and cooler parts of the islands rely on immunity from disease 
and a temperate climate. There he may expect to find 
new types of plants; for the Mountain Flora of Western 
Tropical Africa is wholly unknown; and of its probable 
nature even we can form no guess. To conclude, the Lin- 
n&an axiom of “semper aliquid novi ex Africa" has never 
yet proved false. A Naturalist cannot see the shores of that 
continent without feeling that no other spur is required to 
exertion, in a field to which such a motto still applies with 
so much force. 
(The Plants of this Voyage have proved so numerous, that 
it has been deemed advisable to form a separate volume of 
them, which is now publishing by Mr. Baillière under the 
title of * The Botany of the Niga Expedition.” To : 
he 
Observations sur I’ AMOREUXIA, DC. (Euryanthe, C 21 
Schlecht.) et description des nouveaux genres. Roucner — 
et LosBiA: comme introduction à des mémo ET 
sur les CocnroseenMÉzs, Linées et ARISTOLOCHIÉRS, = 
(familles auxquelles ces genres seront respectivement. rattachés, P 
. 4r J.E. PLANCHON, Docteur-ès-Sciences. 
(Avec trois planches, Tan. I. H. IH Je: 
_ Visoirement, sous un méme titre, des fractions stricte: 
parables de troia mémoires qui nont entreu rien de 
x nici ies = égular 
