For the dycotelodons vegetables one of the principal trunks or a perfectly healthy branch should be taken, and a portion of it 40 or 50 centimetres long preserved; the size best suited for samples is from 10 to 20 centimetres in diameter. Generally the age of the trunk or branch should be such as to have at the same time perfect wood and pulp; for the kinds of wood used for building, it is necessary that the samples should be taken from trunks large enough to give an idea of the physical qualities of the woods. The samples should be sent with the bark entire. If there is danger that they do not dry well and shrink, they should be sawed lengthwise, at some distance from the pith, so that it may remain perfect on one of the pieces, and even in that case, it is well to send, besides the two halves of wood sawed lengthwise, an entire round of from 5 to 6 centimetres thick. All these samples of trunks whether monocotyledons or dicotyledons, should not be boxed or sent off before they are perfectly dry. They should until then be kept as much as possible far from insects. It is indispensable to give interest to these samples of wood, to label them with numbers corresponding with samples of branches with leaves and flowers or fruits dried botanically, so that they can be determined with precision. These numbers should be written on the edge wood cut very plain, either with ink or black crayon, or, better, with paint. When the samples are few, they can be notched or marked with Roman characters cut deep in the wood. It is very important either in the catalogues or in the labels of the samples in the herbals to write the common names which the trees bear, in the country where the samples were gathered, as these names are more generally known for the great vegetables than for the little plants; and by this precaution new information can be more easily obtained concerning the trees. After having indicated the manner of making collections we shall now go on to particularise the vegetables whose trunks we especially desire to obtain. The collection of the museum is already rich in trunks of arborescent fern. Yet it possesses but very few of those which do not belong to the tribe of Cyathees, such as the Diplazium, Dicksonia, Lomaria, Angiopteris.