From these I had in the following year the second hybrid generation, and in the same way I cultivated also the third and fourth. These were as imperfectly fertile as the first, and in [258] some years did not give any seed at all, so that the operation had to be repeated in order to continue the experiment. Last summer (1903) I had a nice lot of some 25 biennial specimens blooming abundantly. All in all I have grown some 500 hybrids, and of these about 150 specimens flowered. These plants were all of the same type, resembling in most points the pollen-parent, and in some others the pistil-parent of the original cross. The most obvious characteristic marks are afforded by the flowers, which in _O. muricata_ are not half so large as in _biennis_, though borne by a calyx-tube of the same length. In this respect the hybrid is like the _biennis_ bearing the larger flowers. These may at times seem to deviate a little in the direction of the other parent, being somewhat smaller and of a slightly paler color. But it is very difficult to distinguish between them, and if _biennis_ and hybrid flowers were separated from the plants and thrown together, it is very doubtful whether one would succeed in separating them. The next point is offered by the foliage. The leaves of _O. biennis_ are broad, those of _O. muricata_ narrow. The hybrid has the broad leaves of _O. biennis_ during most of its life and at the time of flowering. Yet small deviations in the [259] direction of the other parent are not wanting, and in winter the leaves of the hybrid rosettes are often much narrower than those of _O. biennis_, and easily distinguishable from both parents. A third distinction consists in the density of the spike. The distance between the insertion of the flowers of _O. biennis_ is great when compared with that of _O. muricata_. Hence the flowers of the latter species are more crowded and those of _O. biennis_ more dispersed, the spikes of the first being densely crowned with flowers and flower-buds while those of _O. biennis_ are more elongated and slender. As a further consequence the _O. biennis_ opens on the same evening only one, two or three flowers on the same spike, whereas _O. muricata_ bears often eight or ten or more flowers at a time. In this respect the hybrid is similar to the pistil-parent, and the crowding of the broad flowers at the top of the spikes causes the hybrids to be much more showy than either of the parent types. Other distinguishing marks are not recorded by the systematists, or are not so sharply separated as to allow of the corresponding qualities of the hybrids being compared with them.