300 MR. J. BALL’S SPICILEGIUM FLORE MAROCCANS. 
bourhood of Tangier and Tetuan, and are not seen in the central 
or southern provinces of Marocco. 
The Algerian flora, so far as it offers special characteristics to 
distinguish it from the general Mediterranean type, owes its in- 
dividuality mainly to species endemic in the mountain region of 
the Lesser Atlas, or on the high plateaux that present such a pecu- 
liar feature in the geography of Southern Algeria. 
Jt is highly probable that most of these extend into Eastern and 
Central Marocco ; but in the limited region known to us these cha- 
racteristic species of the Algerian flora are for the most part 
wanting, and even in the Great Atlas but a small number of them 
have yet been seen. 
Although several of the species dhatactarinlio of the Desert 
flora extend beyond their original boundary, and a few of them 
are found even in the south-east of Spain, there are few better- 
marked botanical provinces than that of the desert regions of 
WesternAsia and Northern Africa. Considering the wide portion of 
the earth’s surface occupied by the hot stony or sandy plains that 
extend with unimportantinterruptions nearly from the banks of the 
Lower Indus to the Atlantic coast of Southern Marocco, the gene- 
ral uniformity of its scanty vegetable population is a fact very re- 
markable in botanical geography. Unfortunately our knowledge 
of the true desert-region of Southern Marocco, namely that which 
extends along the Southern side of the Great Atlas chain, is ex- 
tremely limited; but when the collections recently received by 
M. Cosson from his collector are fully enumerated, it will be seen 
that many species of this peculiar type extend to within a few 
leagues of the Atlantic coast. But even in the low country, 
on the northern side of the Great Atlas, traversed by us there are 
some considerable tracts closely approximating in their physical 
conditions to the northern skirts of the Sahara. Many of the 
characteristic desert-species there reappear, although they are 
separated by lofty mountain-ranges from what may be considered 
their natural home. 
The least-important element that goes to make up the Marocco 
flora, if we measure it by the number of representative species, 
but in some respects one of the most interesting, is that revealed 
by the presence of a small number of species common to the Ma- 
roccan and the Macaronesian* floras. Of these all but one are 
* T have ventured to use the name Macaronesia in a rather wider sense than 
some preceding writers, including under it Madeira with its dependent islets, 
