OVOVIVIPAROUS, a term applied to animals of which the egg is hatched within the body of the mother, so that the young is excluded alive, although the fetus has been inclosed in an egg almost to the time of parturition. It is probable that the egg is often broken in parturition itself. Sonic fishes are ovoviviparous, and some reptiles; also tiro monolrentata. The common lizard and the viviparous lizard, both natives of Britain, are illuStrations of the near resemblance which may subsist between oviparous and ovoviviparous animals. The distiuction is much less important than might be supposed.
(Lat. a little egg), in botany, the rudimentary seed. The germen (q.v.) or ovary sometimes contains only one ovule, sometimes a small definite number, sometimes a large indefinite number. Ovules are to be regarded as metamorphosed buds. "Thu single ovule contained in the ovaries of compositte and grasses may be called a terminal bud, surrounded by a whorl of adhering leaves or carpels, in the aril of one of which it is prodnced."—flzdfour, Manual of Botany, The ovule is not always contained in an ovary. In gymnogens (q.v.) it is wanting, and the ovule is naked; but the plants pos. sessing this characterare comparatively few. The ovule is attached to the placenta (q.v.). and by it to the carpel (q.v.), from which it is developed. The attachment to the placenta is either immediate, when the ovule is said to be sessile, or by means of an umbhical cord (funicalus), which sometimes elongates very much after fecundation. The ovule is, in general, essentially formed of a cellular nucleus inclosed by two mem branes, the outer of which is called the priolinc, and the inner the secandine. At one
end of the nucleus there is mm opening of both membranes—the furamen—th•ough which the access of the pollen in fecundation (q.v.) takes place. The eltalaza (q.v.) unites the nucleus and these membranes at the base. When the ovule is so developed that the chaluza is at the base, and the foramen at the apex, it is said to be orthotropal(Gr. ortkos, straight, tropes, a mode). When the ovate is bent, so that the foramen is brought near to the base, it is called cautpylotropal (Gr, kamp?fios, curved). When by increasing on One side more rapidly than on the other, the ovule has its foramen close to the base, the chaliza being carried round to the opposite extremity, the ovule is anatropal (Gr. ana trepo, to turn upside down). Anatropal ovules are very common. When the ovule is attached to the placenta, so that the foramen and chalaza are at opposite ends, the base being in the middle, it is called amphitropal (Gr. antpki, around).—When the ovule arises from the base of the germen, it is said to be erect; when it harm from the apex df the cavity of the germen, it is pendulous; when it arises from the side of the germen above the base, it is ascending; when it hangs from the side of the germen below the apex, it is suspended. When two or more ovules are found, not only in the same ovary, but in the same cell, they generally exhibit different modes a attachment. See CIIALAZA, EMBRYO,