=Suppression of ovules,--abortion of seeds.=--The two cases are taken together, as the effects are similar, though it must be remembered that in the one case the ovules at any rate have been formed, but their development has been arrested, while in the other they have never existed. The precise cause that has determined the absence of seed cannot in all cases be ascertained in the adult condition, hence it is convenient to treat the two phenomena under one head. Many plants in other than their native climates either produce no fruit at all, or the fruits that are produced are destitute of seed, _e.g._ _Musa_, _Artocarpus_, &c. Some of the cultivated varieties of the grape and of the berberry produce no seeds. Suppression or abortion of the seed is frequently associated with the excessive development either in size or number of other portions of the plant, or with an altered condition, as when carpels become foliaceous and their margins detached. Hybridisation and cross fertilisation are also well-known agents in diminishing the number and size of seeds. =Meiotaxy of the parts of the flower in general.=--In the preceding sections suppression has been considered as it affected individual members of a whorl or separate whorls. It rarely happens, however, that the suppression is limited in this way. More generally several of the parts of the flower are simultaneously affected in the same manner. A few illustrations are all that is necessary to give as to this point. One of the most familiar instances is that of the cauliflower or broccoli, where the common flower-stalk is inordinately thickened and fleshy, while the corolla and inner parts of the flower are usually entirely suppressed; the four sepals can, however, generally be detected. Maximowicz describes a _Stellaria_ (_Kraschenikovia_) in which the upper flowers are male only, while the lower ones, which ultimately become buried in the soil, have neither petals, stamens, nor styles, but the walls of the capsule are fleshy, and enclose numerous seeds.[486] Kirschleger[487] mentions a variety of _Lonicera Caprifolium_, which was not only destitute of petals but of stamens also. In some species of _Muscari_ and _Bellevalia_ the uppermost flowers of the raceme show more or less complete suppression of almost all the part of which the flower normally consists. In those cases where an imperfect perianth exists, but in which the stamens and pistils are entirely suppressed, Morren applies the term Cenanthy, [Greek: kenos], empty.