114 



ever, must be very much restricted. He even states himself, 

 towards the conclusion of his work, that the bulb may be re- 

 garded as a symbol of immortality, just as much as the dying 

 seed might serve as a general proof of the continuance in death. 



M. Ohlert* has published some highly interesting obser- 

 vations on the position and farther development of the buds 

 of our common trees and shrubs. With the appearance of 

 the young leaves on the bursting of the bud, appear almost 

 contemporaneously in their axillae the young buds for the 

 next year, which are further developed in the summer and 

 autumn ; the scales of the buds are soon perfected, but the 

 inclosed leaves appear still to increase during the winter, which 

 as I have myself observed is at least the case in some plants. 

 The number of scales is quite constant for each species, and at 

 their opening in spring the buds have the same number of 

 leaves. There is a relative definiteness in the number of the in- 

 ternodes, which the annual shoot, i. e. the developed buds, ex- 

 hibits, the number of internodes in the different species never 

 exceeding a certain maximum ; moreover it often coincides 

 with the number of leaves or leaf-pairs which are formed ante- 

 riorly in the bud. M. Ohlert adduces in a table some excel- 

 lent proofs. Thus Fraxinus excelsior has two pairs of scales, 

 five leaf pairs, and at the utmost 3 internodes in the annual 

 shoot ; Msculus Hippocastanum seven pairs of scales, five of 

 leaves, five internodes ; Acer campestre six pairs of bracts, five 

 of leaves, ten internodes ; Sorbus aucuparia three pairs of 

 scales, five of leaves, eight internodes, &c. 



M. Ohlert then observes, that at times, as in Tilia, &c. the 

 axillary bud becomes apparently terminal, but that it is easily 

 recognized on dividing it. 



In the buds of some trees and shrubs more leaves are formed 

 than are to arrive at development, upon which the leaves at 

 the apex of the branch dry and fall off, for instance, in Sy- 

 ringa, &c., consequently no terminal buds originate in this 

 case. In other cases there are fewer leaves in the bud than 

 the young branch developes members, as in Ulmus campestris, 

 Tilia Europcea, &c., where also no terminal buds are formed ; 

 or as in Fraxinus, Acer, Cornus, Quercus, &c., where terminal 



* Einige Bemerkungen iiber die Knospen unserer Baume und Straucher. 

 Limuea, v. 1837, p. 632. 



