122 CLOVER CULTURE. 



clear understanding of the parts of the flower. The clover flower con 

 sists of two kinds of organs, known as the essential and non-essential. 

 The F ssential are absolutely necessary in the production of seed. The 

 non-essential, which surround the former, consist of two sets of modified 

 leaves, the outer known as the calyx. This is green and made up of ar 

 enlarged lower portion which bears five bristle-shaped lobes. Next tc 

 the calyx is the colored part of the flower, known as the corolla, or, in 

 common language, the blossom. It is made up of five parts known as 

 petals. Flowers, like clover, in which the petals are unlike in size, are 

 known as irregular, and many irregular flowers need insects to carry 

 the pollen. In some flowers both calyx and corolla are absent, but in no 

 case can seed b produced where the stamens and pistil, the essential 

 parts of the flower, are absent The stamens occur next to the corolla, 

 while the pistil is found in the center. The corolla of the clover floret* 

 consists of the following parts: An upper, larger petal known as the 

 bearer, two lateral petals known as the wings, and two lower petals 

 resembling the keel of a boat, which are united and are commonly 

 known as the "keel." The keel contains the ten stamens, each seamen 

 consisting of an anther, at the end of which *s attached a thread-like 

 affair known as the filament. But in the case of clover the filaments 

 are united to form a tube, the anthers containing the pollen. The pistil 

 is also found in the keel. The expanded portion contains the unde- 

 veloped seeds. The narrow neck is known as a style, the tip is the 

 stigma. The color of the clover flower is especially attractive to insects. 

 The honey which the insect seeks is contained in the tube formed by the 

 union of the fine, thread-like bodies or filaments. 



When an insect like the bumbie-bee lights on the flower, it uses the 

 keel and wings (the latter being attached to the tube containing the 

 nectar) as a resting place, its weight pressing the keel down and causing 

 the pistil and stamens, the latter being somewhat shorter than the pistil. 

 to come in contact with the underside of the bee's head. The insect is 

 certain to leave some of the pollen from another flower on the stigma. 

 The honey is obtained by the insect thrusting its proboscis into the 

 united filaments of the stamens, which has a slit on the upper side to 

 give place for a free tenth stamen. Self-pollination, or pollination of 

 the flower from its own stamens, is not excluded, as the insect leaves th* 

 flowers. Does self-fertilization occur? Charles Darwin (Cross and 

 Self-Fertilization, page 361) says: "One hundred flower heads on 

 plants protected by a net did not produce a single seed, whilst one hun- 

 dred heads on plants growing outside, which were visited by bees, 

 yielded sixty-eight grains weight in seed," making a total of 2720 seeds 

 for the one hundred heads. Mr. Sirrine (Bulletin 13, Iowa Agricultural 

 Experiment Station, page 90) found that when pollea of the same flower 

 was used, no seed set. Prof. Cook (Bulletin 26, Division of Entomology 

 United States Department of Agriculture, page 87) found that in ten 

 heads of white clover from which insects were excluded, no seed set. 

 In a similar pot of ten heads not protected from insects by gauze, seeds 

 set. In ten heads of red clover covered, no seeds set ; in a similar pot 

 not covered, seed were produced. Prof. Beal, in Grasses of North 

 America, pages 325-328, inclusive, also shows the inability of clover to 

 self-fertilize. It is well known that before the introduction of the 

 bumble-bee into Australia and New Zealand, clover did not set seed, but 

 since the British Government introduced the bumble-bee in 18:4, clover 

 seeds are produced. They have since multiplied with remarkable 



* The heads of red and mammoth clover are made up of from twenty to sixty flower*. 

 n florets, each separate in their structure and together forming what is ordinarily 

 *nown as the clover blossom. 



