ALASSIO AND ITS FLORA 
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flower head surrounded by an involucrum 
of 4-5, rarely 6 subtrilobate, patent small 
leaves with very sharp thorns. 
Flower's head globular, of a bluish-white 
tint; flowers sessile oblong accompanied 
by a small 3-toothed bract longer than 
the flower; the 5 teeth of the calyx are 
linear, prickly. Petals 5, white, inflex op- 
posite to the sepals, and embracing in their 
fold the anther which is linear, vertical 
and has a groove in which the stamini- 
terous filament passes, rises, and then bends 
to insert itself in the middle of the anther. 
Columella divided in two, attached to the 
achenes. 
