M. >on Martius on the Growth of the Stem of Palms. 415 



carefully traced, and some of the theories propounded on this 

 subject have been discussed on this occasion ; but we do not 

 think it necessary to consider them here, as the L. clandestina 

 does not offer anything peculiar in this respect. 



It is also to be regretted that M. Duchartre has not been able 

 to follow out the mode of formation of the embryo and its sub- 

 sequent germination. 



Notwithstanding these slight omissions, the investigation of 

 M. Duchartre is not less one of the most complete on the ana- 

 tomy and organogeny of a particular vegetable ; it has appeared 

 to us very exact in all the points which we have been able to ve- 

 rify, the author is quite conversant with the modern labours re- 

 lative to the different subjects which he has treated, and we are 

 of opinion that it would be desirable for the progress of botany 

 that the science should possess several anatomical monographs 

 made with the same care. For these reasons, we propose to the 

 Academy to give its approbation to the memoir of M. Duchartre, 

 and to insert it in the ^ Memoires des Savants Etrangers.' 



LXl. — On the Growth of the Stem of Palms, and on the Decur- 

 rence of the Leaves. By M. von Martius*. 



Permit me to present to you some pages of the Bulletin of our 

 Academy, in which I have stated the results of my researches on 

 the growth of the stem of Palms, and on the decurrence of the 

 fibres. These results may be reduced to the following points : — 



1. The stem of Palms does not contain more fibres than are 

 destined to enter sooner or later into the leaves. 



2. The fibres originate on the summit of the stem, in nucleo 

 gemma, vel in phyllophoro Mirbelii, between the new and plastic 

 parenchyma which there forms a peculiar conical layer, covering, 

 like a funnel, the more aged parts. They are always external with 

 relation to the others, which are already formed, and a little 

 higher. 



3. The points of origin of the fibres are organically predis- 

 posed j we find, in these points, the fibres situated obliquely, and 

 converging at their upper ends. They are elongated from the 

 two ends, that is to say, they grow from below upwards and from 

 above downwards. 



4. The upper extremity of these fibres is directed towards the 

 base of the young leaf; the latter originates in the form of a cel- 

 lular fold {plica, crista) in the centre of the bud, and is conducted 

 toward the periphery on becoming enlarged. 



* Being an extract of a letter to M. Flourens,. Comptes Rendus for 

 April?, 1845. 



