12 EXPLANATION OF TERMS 



pass through this tube and unite with elements in the ovule, after which the 

 latter develops into a fertile seed. The element derived from the pollen is 

 the male element, while that in the ovule is the female element and, with 

 few exceptions, their fusion is essential if fertile seeds are to be formed. 

 Flowers which contain stamens but not pistils are staminate, or male 

 flowers; those which bear pistils but not stamens are pistillate, or female 

 flowers. Most flowers produce both stamens and pistils. 



Simple pistils are those composed of a single fundamental unit 

 (carpel). They always produce a one-celled fruit, and this may 

 contain a number of seeds, as in the Pea pod, or a single seed, as 

 in the Plum and Cherry. These simple pistils may occur singly 

 in each flower, as in the Pea, or they may be numerous and 

 heaped up in the middle, as in the Buttercup and Raspberry, but 

 so long as they do not actually fuse into one body they are distinct 

 pistils. When a simple pistil produces but one seed in a dry and 

 hard outer covering (ovary wall) which does not open at 

 maturity, it is called an akene. The seed-like bodies in the Com- 

 posite Family and in the Buttercup are akenes. A compound pistil 

 is formed by the fusion of several parts into one body, as may be 

 indicated by the several cells to the ovary or by the distinct styles 

 or stigmas. Most seed-vessels contain several cells and result 

 from a compound pistil, as in Flax, Azalea, and Grape. One- 

 celled ovaries with several distinct styles are less common. St. 

 Johnswort is an example. 



Superior ovaries are those which are entirely free from the 

 calyx, i. e., the calyx is not in any way adherent to the ovary, 

 which is attached to the receptacle. The Lily, Poppy, Mustard, 

 Pea, Pentstemon, and in fact most flowers have superior ovaries. 

 An inferior ovary is one to which the calyx is firmly united, so 

 that it cannot be pulled away without tearing the ovary, as in the 

 Orchid, Evening Primrose, and Godetia. The calyx in this case 

 surrounds the ovary and is also attached to it, while the ovary 

 itself is attached to the receptacle farther down and in this sense 

 is "inferior." As the inferior ovary ripens, the calyx matures 

 with it, forming an outer coat which often gives additional pro- 

 tection to the seeds. In some cases the calyx is attached only 

 part way up, giving us a half-inferior ovary, as in some members 

 of the Saxifrage Family. 



The Fruit and Seed. 

 The fruit consists of the ripened ovary and whatever other parts 

 persist until the seed is ripe. In this sense a fruit need not be 

 fleshy or pulpy. Pods, burs, capsules, etc., are botanical fruits. 

 The seed is the mature ovule. It contains an embryo, or young 

 plant, and often a mealy, oily, or albuminous substance which 

 supplies nourishment for the growing plantlet after germination. 



