Examples of punctures more or less entirely grown over on the trees whose wood is very different from that of indigenous trees, such as the very soft woods of Baobab, the Papayers, and on the very hard woods as iron wood, ebon, etc.
2o The excrescences and other anomalies of the developement of these woods, by knowing exactly the tree on which they have been observed or gathered.
3o The parasitical plants inserted on the trunks or roots, which bear them, such as the loranthus, viscum, and other parasites on the branches, the Rafflesia hyduora, balanophara on the roots; these samples, showing the parasitical plants still fixed on a portion of the plant which nourishes them, ought to be preserved dry for the ligneous species, in alcohol, for the herbaceous or pulpy species.
4o Monstruosities or anomalies of structure of flowers or exotic fruits, preserved in alcohol.
Fossil vegetables.—The collections of this kind at the museum (for several years) have greatly increased, and the researches of travellers and correspondents of the establishments will soon give them still more importance. Up to this present time, these collections comprehend, almost entirely, the fossil vegetables of Europe; yet it is known that the soils that produce them are found in the most remote parts of the world, and the comparison of fossils coming from great distance would be of great interest for geological theories. Thus, coal-land, so rich in fossil plants in Europe, is excavated at a great number of points in North America, in the East Indies, in China, and New-Holland, and is found, without doubt, in other places; the mines of the United States have been worked with care for the fossils which they contain, and have already supplied our galleries with numerous specimens.
It must not be forgotten that to classify exactly these fossils considerable number of specimens is frequently necessary and that a collection of the varieties found together in the same soil is often one of the most important results; that consequently, especially in distant localities, the greatest number of specimens possible should be collected and sent.
Specimens should especially be procured which present the stamps of leaves entire and perfectly marked, the trunks which show still the carbonised bark which covered them, and the impression of the insertions of the leaves that it bore, besides characterised fruits, such as those analogous to the cones of the pines, the fruits of the palm trees, etc.
Coal-land, although more rich, in general, than any other in vegetable fossils, is not the only one which contains them; the secondary formation, and the tertiary present also numerous impressions of leaves, of branches, of flowers even and of fruits, whose succession at different epochs of formation, and comparative structure in various countries of the world is not less interesting. Their acquisitions cannot be too strongly recommended; but it is necessary, as much as possible, to join to these fossils, the animal fossils which may accompany them, which will better tend to determine the epoch of the formation of the deposit which contains them.
There is still another class of vegetable fossils which, in later times, has acquired more importance than has been given to them before; they are petrified woods which by a new process of preparation, permit to study their interior organisation, and to compare them to living woods; these woods are found in the deposits of every epoch, and in countries the farthest separated. They belong to families and classes very different; thus their examination is very important. It should be recommended to persons, who encounter them, to collect them with great care, in choosing pieces which appear to differ, not so much by their exterior form as by their interior structure.
It is not necessary to send large samples of the characteristics which distinguish them as regards their interior structure and especially for the dicotyledonous woods with concentric layers; it is best, on the contrary, to break them neatly with the hammer and to reduce them about 1 decimetre cube. The only large pieces which ought to be preserved are those of the monocotyledons, which as the woods of palms and the woods which would be analogous to the trunks of the tree ferns, for there it is necessary, as much as possible, to have the trunk entire from the centre to the surface and in length of 2 to 3 decimetres. Among places where the most remarkable and varied fossil woods have been found, we would cite the little Antilles, above all Antigua, Saint-Lucy and the Martinique. The museum possesses but few specimens from these places.