Corylus, _Tournefort_. Name from _korys_, a hood, helmet or bonnet, in reference to the form of the calyx or husk enclosing the nut. Order, _Corylaceæ_. Deciduous trees or low shrubs. Male flowers appearing in the autumn in pendulous cylindrical catkins two inches or more in length, with a two-cleft calyx partly united with the bracts or scales. These catkins remain on the plants all winter, becoming fully developed, and shedding their pollen early the following spring. Female flowers minute, entirely hidden within the buds during the winter, but early in spring their bright red, thread-like stigmas push out from the tips of the lateral or terminal buds. Ovary two-celled, with one ovule in each. Nut globular, ovoid or oblong, often in clusters, but each enclosed in a leafy, two- or three-valved husk, fringed or deeply notched at the upper end. Leaves broadly heart-shaped, serrate, with sturdy, short leaf-stalks. The filbert and hazel always bloom before the leaves appear in spring, and the male catkins usually open and begin to scatter their pollen in this latitude during warm days in March, the females soon following, their bright-red stigmas pushing out from the ends of the buds, but as soon as fertilization has been consummated they shrivel and disappear. The trees may then remain leafless for weeks following, and yet produce a heavy crop of fruit. [Illustration: FIG. 37. LARGE FILBERT.] The common English name, filbert, is from "full-beard." All the varieties with husks extending beyond the nut, and with fringed edges, are filberts (Fig. 37); while those with husks shorter than the nuts (Fig. 38) are hazels, from the old Anglo-Saxon word, _hæsel_, a hood or bonnet. The parentage, size, form or quality of the nut, is not to be considered in this classification, for when the nuts are ripe and fallen from the husks, there is nothing left to distinguish the hazelnuts from filberts, unless a person is sufficiently familiar with a variety to know to which group it belongs. In France these nuts are known under the general name of _Noysette_; while in Germany it is _Haselnuss_; in Holland _Hazelnoot_; and in Italy _Avellana_, from Avellana, a city of Naples, near which there is a valley where these nuts have been extensively cultivated for many centuries. [Illustration: FIG. 38. LARGE SEEDLING HAZELNUT.]