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 shape. By a selection of this kind the quality of the crop can be greater improved.

One of the peculiarities of the peanut is that it is an underground legume. All other leguminous fruits mature above the soil. Its underground habitat is the reason for its botanical name, hypogæa. If the stem carrying the small, yellow, butterfly-shaped flowers and which springs from the axis of the branch above the ground fails to reach the soil no fruit is formed. If the soil is properly cultivated the germ may penetrate of its own accord. However, art assists nature in this matter and covers up the pods so as to give them a better start. The peanut, like some other leguminous crops, develops nodules upon its roots in which the bacteria that assimilate free nitrogen live in symbiotic union with the plant itself.

Pecan-nut (Hicoria pecan (Marsh.) Britton; Carya olivæformis Nuttall).—The pecan is a nut which is very much valued and grows, with a most excellent flavor, in the southern part of the United States. Texas, Louisiana, southern Alabama, Mississippi, Georgia, and Florida are the principal regions where the pecan grows, although it is cultivated in some instances much further north.

The pecan belongs to the same family as the hickory-nut and is indigenous to the United States. It grows wild over a large area, extending from southern Illinois and Indiana to the Gulf. It often forms very large trees in the forests. There are several species of Hicoria. The fruit of the pecan is especially valued on account of the thinness of the shell and its extremely pleasant and aromatic flavor. As is the case with most nuts, it is composed chiefly of oil and proteids, the sugar and starch being in minute proportions. The composition of the fruit of the pecan, when divested of its hard shell, is given in the following table:

Water,                    2.9 percent Protein,                 10.3 " Fat,                      70.8 " Sugar, starch, etc.,     14.3 " Ash,                       1.7 " Calories per pound,     3,445

For marketing purposes the pecans are now largely grown in orchards, as the supply of the wild nut is uncertain, and its texture and flavor are not so fine as the cultivated variety. The cultivated variety may also be grafted upon the wild tree with good effects. The tree begins to bear at four or five years of age. A comparative appearance of the wild and cultivated nut is shown in the accompanying Fig. 59. The tree, when full grown, is handsome in appearance, and is valued as a shade tree as well as a fruit producer. The full grown tree is shown in the accompanying Figs. 58 and 60.

Pine-nuts.—In many portions of the western part of our country pine-