The Marismas of Guadalquivir 89 
flat, and which vary in extent from a few yards to hundreds of 
acres. ‘The precise geological cause of these vetas we know not; 
but the calcareous matter of which they are composed—the debris 
of myriad disintegrated sea-shells, mostly bivalves—proves that 
the ocean at an earlier period held sway, till gradually driven 
backwards by the torrents of alluvial matter carried down by the 
river, and finally forced behind the vast sand-barrier now known 
as the Coto Dofiana—the buffer called into being whilst age-long 
struggles raged between these two opposing forces. The fact is 
further evidenced by the salt crust which yearly forms on the 
surface of the lower marisma when the summer sun has evaporated 
its waters. 
In summer the marisma is practically a sun-scorched mud-flat ; 
in winter a shallow inland sea, with the vetas standing out like 
islands. 
There are, as already stated, slight local variations in elevation. 
Naturally the lower-lying areas are the first to retain moisture 
so soon as the long torrid summer has passed away and autumn 
rains begin. Speedily these become shallow lagoons, termed 
luwctos—similar, we imagine, to the jheels of India—and a 
welcome haven they afford to the advance-guard of immigrant 
wildfowl from the north. 
Plant-life in the marismas is regulated by the relative saltness 
of the soil. In the deeper ducios no vegetation can subsist ; but 
where the level rises, though but a few inches, and the ground is 
less saline, the hardy samphire (in Spanish, armajo) appears, 
covering with its small isolated bushes vast stretches of the lower 
marisma. 
The armajo, which is formed of a congeries of fleshy twigs, 
leafless, and jointed more like the marine algae than a land-plant, 
belongs to three species as follows :— 
(1) Salecornea herbacea, marsh-samphire; in Spanish, Sapina. 
(2) Arthraenimum fruticosum 
(3) Suaeda fruticosa 
All three belong to the natural order Chenopodiaceae (or 
‘“ Goose-foot” family). 
The armajo is the typical plant of the marisma, flourishing 
even where there is a considerable percentage of salt in the soil. 
This aquatic shrub increases most in dry seasons, a series of wet 
winters having a disastrous effect on its growth. The Sapina, 
\in Spanish, Armayjo. 
