PHYSIOLOGICAL BOTANY. 253 



definitely alluded to the fact that the Palm grows at the 

 summit only, and that the vascular bundles arise from 

 the interior solely at that part, and grow towards the 

 leaves. Hence I cannot agree with Gaudichaud's opinion, 

 that the vascular bundles arise from the leaves, although 

 he has often quoted me amongst a singularly-enough se- 

 lected series of authors who are of his opinion. Neither, 

 on the other hand, can I agree with Mirbel, in considering 

 that vascular bundles arise from the interior of the stem. 

 The growth takes place at the summit only, and there 

 the vascular bundles come out from the interior. 



Gaudichaud's "Memoirs against Mirbel," are in the 

 'Compt. rend./ 1845, i, 1375, 1436, and 1677, and 

 ii, 99, 20], and 261; the memoir upon the Stem of 

 Ravenala, in the same year (ii, 391), must also be 

 referred here. 



Dr. v. Martius has written a paper Upon the Process 

 of Growth in Palms, especially as regards the Course of 

 the Fibres in the 8tem, which was published in the 

 ' Gelehrte Anzeige' of the Royal Academy of Sciences of 

 Bavaria, for February, 1845. The author communicates 

 his results to the Academy of Sciences at Paris ; hence 

 they are given in the 'Compt. rend./ 1845, i, 1038. 

 Gaudichaud has expressed himself strongly upon and 

 against them (p. 1207). Mirbel also is dissatisfied with 

 them. This was to be expected; he who takes the 

 middle path is repulsed on both sides. The vascular 

 bundles, says the author, originate at the summit of the 

 growing point, in the nucleus of the bud or " pJiyllo- 

 phore" (according to Mirbel), in the substance of the 

 more recent cellular tissue which is in course of develop- 

 ment, and which here forms a peculiar layer, coating the 

 older and subjacent parts like a mantle ; the recent ones 

 being always formed externally to, and more or less above, 

 those already developed. This is explained in the sub- 

 sequent parts of the memoir as follows : As the young 

 plant, even in its first stage after germination, is furnished 



