This section is from the book "Commercial Gardening Vol1", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
A young seed before it has been fertilized is termed an ovule. A Buttercup or Strawberry contains only one ovule in each carpel; a Cherry or Peach contains two, but only one reaches maturity. The Pea may have from four or five to a dozen, arranged along the edges of the ventral suture, one of the two separable edges of the pod. The Pansy has numerous ovules, in three distinct rows on the side walls of the ovary, and defined as parietal. In the White Lily they are on the inner angles of the cells of the ovary, and therefore axile. The part to which they are attached is termed the placenta in each case. The placenta is free and central in the Chinese Primula, and the ovules are inserted all over it.
Fig. 52. - A Monoecious Plant.
1, Pistillate flowers on upper part of twig of Oak (Quercus pedunculate); staminate flowers in drooping catkins below (nat. size). 2, Single pistillate (female) flower. 3, Three staminate (male) flowers, x 4.