85, 86.] 



THE LEAF-BUD. 



with the lateral halves brought together face to face, 

 as in the Oak ; 'Plaited, or Plicate, each leaf folded 

 like a fan, as in Birch. 



255. Circinate implies that each leaf is rolled or 

 coiled downward from the apex, as in Sundew and 

 the Ferns. 



256. The Convolute leaf is wholly rolled up from 

 one of its sides, as in the Cherry ; while the Involute 

 has both its edges rolled inward, as in Apple, Violet ; 

 and the Revolute has both margins rolled outward and 

 backward, as in the 



Dock, Willow, Rosemary. 



Vernation, 283, of Birch leaf ; 284, of Lilac (imbricate) ; 285, Cheny leaves (convolute) ; 286, Dock bud 

 (revolute) ; 287, Balm of Gilead (involute). 



257. The general vernation is loosely distinguished 

 in descriptive botany as valvate (edges meeting), and 

 imbricate (edges overlapping), terms to be noticed 

 hereafter. The valvate more often occurs in plants 

 with opposite leaves ; as in the St. John's-wort family, 

 Hypericum Sarothra (275). 



258. Imbricate vernation is Equitant (riding astrad- 

 dle), when conduplicate leaves alternately embrace 

 the outer one the next inner by its unfolded margins, 

 as in the Privet and Iris (282). It is Obvolute when 

 it is half-equitant ; that is, the outer leaf embraces 

 only one of the margins of the inner, as in the Sage 

 (281). Again, it is Triquetrous where the bud is tri- 

 angular in section and the leaves equitant at each 

 angle, as in the Sedges (280). 



