oi ih;ds. 285 



in their development, and are more or less completely 

 changed into scales. When we examine the structure 

 of a bud of the Ash or Sycamore in spring, we see the 

 external scales short, hard, of a reddish brown colour, 

 and slightly downy, and the inner rows gradually be- 

 come more membranous, paler, and longer; afterwards 

 they bear at their extremity the rudiments of leaflets ; 

 then they become small leaves, so that it is impossible 

 to doubt that the external pieces are of the same nature 

 as the internal. 



Buds have received particular names, according as 

 they are formed by different portions of the foliaceous 

 organs, and according to the degrees of their degenera- 

 tions and adhesions. 



1st. We say that buds are Foliaceous when the 

 leaves being sessile, their limb, reduced to the form of a 

 scale, forms the buds, as in Daphne Mezerewn. 



2d. Buds are said to be Petiolaceous when the 

 bases of the petioles, dilated into scales, form the co- 

 vering of the young shoot; this is seen in exstipulate 

 petiolate leaves, as the Walnut, the Ash, the Horse-chest- 

 nut. (PI. 12.) 



.'id. Stipulaceous buds are those which are formed, 

 not by the leaves, but by the stipules, which are not 

 united to the petiole. We distinguish two kinds of 

 stipulaceous buds: 1st, those which are formed by 

 the superposition of a great number of stipules which 

 together inclose an entire young shoot ; this hap- 

 pens in almost all the Amentaceae, as the Oak, Willow, 

 Elm, &c. ; 2d, those, the stipules of which, free 

 or united together by their outer margin, form the 

 peculiar envelope of each leaf, and are gradually de- 

 veloped with the branch itself; this is seen in Ficus, 

 (PI. 6) and the Magnoliaceae ; these kinds of mono- 

 pbyllous buds can be recognised at first sight by their 



