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.
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