OF THE ORGANS. 



33 



III. Buds, Leaves, and Parts connected with them. 



In most plants, especially of the lower kind, there are pro- 

 duced by a crowding together of the constituent parts, what 

 liave been named the germs {germma, gongyli). These are 

 small spheres, or opak« grains, which are collected together, 

 and from which new shoots or new individuals ai'ise. Wh«n 

 they have grown somewhat larger, they are Q,3i\{edi propagines, 

 propagida ; and their union into something like small plots 

 is named soroBdia. The layer of cellular texture in which 

 these germs lie, is called lamina proligei^a^ especially in the 

 Lichens. 



In higher plants the germs press so much upon one another, 

 that they commonly make their appearance enveloped by 

 scales, in the axes of the leaves. They are then called buds 

 (gemma) or ei/es, (Tab. IV. Fig. 2. 8.) 



73. 



The forms of buds are extremely various, (304.) Some of 

 them remain hidden under the epidermis, and are then only 

 small knots, composed of compact granular masses, or of 

 the substance of leaves, as in various tropical trees. Most 

 of the buds of trees belonging to the temperate zones, appear 

 as oval, pointed, or angular organs in the axes of the leaves. 

 In the Prunus depressa, Pursh, two flower-buds stand one on 

 each side of the leaf-buds. They often take the appearance 

 of actual tubers, and even of small bulbs, as in Dentaria huU 

 'bifera, and most plants of the same species, where they ap- 

 pear between the blossoms. They are in their simplest form 

 in the Tulip-tree (Tab. IV. Fig. 3. 4.), and consist merely of 

 two flat scales lying upon one another, between which the fu- 

 ture leaf appears. At the base of the leaf-stalk, we see the 

 two scales of the buds of the second generation, and w e thus 

 often see from three to four generations included. 



The scales of which buds are composed, lie commonly in 

 such a manner upon one anoflier, that one covei's the half of 



