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A TEXT-BOOK OF BOTANY 



feet) that swells at the end into a large globular float, to 

 which are attached leaves often ten or twelve feet long 

 (Fig. 109). The sea-palm has a thick erect stem that bears 

 a crown of large drooping leaves (Fig. 110). 



FlG. 109. A bladder kelp. After POSTELS and RUPRECHT. 



Another group of brown Algae is represented by the rock- 

 weeds (called also wrack) and the gulfweeds. The former 

 (mostly Fucus) cover the rocks between tide-marks, being 

 ribbon-like forms repeatedly forking at the swollen tips 



