OR APPENDAGES OF PLANTS. 169 



pale floral leaf, attached to the flower-stalk. The 

 Lavenders,/*. 118, see Curt. Mag. . 400 and 401, 

 have coloured bracteas, and the Purple-topped Clary, 

 Salvia Horminum, Ft. Gr&c. t. 20, exhibits a gra- 

 dation from the proper leaves to green bracteas, and 

 from them to coloured ones, which last are barren, 

 or unaccompanied by flowers. Hence I am induced 

 to believe this plant a mere variety of S. viridis, 

 t. 19, all whose bVacteas are green and fertile. 

 Bartsla alpina, Engl. Bot. t. 361, and Melam- 

 pyrum arvense, t. 53, display an elegant transition 

 from leaves to coloured bracteas. The Orchis tribe 

 have green leafy bracteas, different in size in diffe- 

 rent species. A most beautiful large and coloured 

 bractea is produced in Musscenda frondosa, Hort. 

 Mai. v. 2. t. 18, from one of the teeth of the calyx, 

 also in M. glabra of Willdenow, and two new 

 species brought from America by Mr. John Fraser. 

 Spinous bracteas of a curious construction guard the 

 calyx in Atract i/lls cancellated f. 119. Li nnieus ob- 

 serves that no bracteas are to be found in the class 

 Tetradynamia. 



The ocrea of Rottboll, JVilldenotvs Principles 

 of Botany, 50, which enfolds the flower-stalks in 

 Cyperus, see Engl. Bot. t. 1 309, seems to me a 

 species of bractea. 



3. Spina.f. 120. A Thorn. This proceeds from the 

 wood itself, and is either terminal like Hippophae 



