Sarracenias with that of Their Parents 33 



Ovarian Gland Structure 



The above description applies to the glands present on all 

 the vegetative parts, as well as on the bract, sepals, the petals 

 and umbrelloid style. But over the tubercles on the surface of 

 the ovary are still more complex glands. Macfarlane (28) 

 gives the following description of the nectar secretion: 'The 

 epidermal cells of the ovarian surface have undergone repeated 

 divisions, and have swollen out into minute glassy beads or 

 tubercles from which a quantity of rich nectar exudes before, 

 during, and for some time after, blossoming. This, as we will 

 show, is evidently of great use in the pollination of the flower." 

 "When a flower has nearly opened the stamens begin to dehisce 

 and as the blossom has a pendulous position the pollen from the 

 stamens is showered down into the umbrelloid style-cavity below. 

 But about this time the warted bead-like ovarian surface exudes 

 large drops of sweet juice, which increases in quantity as the 

 stamens continue to dehisce, till it oozes down among the fila- 

 ments and anthers, washing with it the pollen-grains. It then 

 accumulates in the umbrelloid cavity, and forms there a nectar- 

 bath of pollen." 



When serial sections of the ovarian wall of an opened flower 

 are studied, the source of the abundant honey is seen to be in 

 the large nectar glands situated at the bases, and along the 

 sides, of the tubercles mentioned above by Macfarlane. The 

 glands are more numerous over the tubercles of the lower half 

 of the ovary. The tubercles over the upper surface of the ovary 

 are devoid of glands. Following is an account of the mode of 

 origin of the tubercles and glands: 



In a very young flower, where the anthers show the pollen 

 mother cell stage, the ovary is as yet very small, and its epi- 

 dermis smooth. The ovarian tissue is, however, growing rapidly 

 at this period, and division figures are frequent. They indicate 

 a longitudinal division for the epidermal cells invariably, while 

 in the subjacent tissue both longitudinal and transverse 

 divisions are common. At this time both petals and sepals 

 possess fully formed glands and stomata. The ovarian wall as 

 yet shows no trace of either. The epidermis continues to 

 divide more frequently than the tissue below. This excessive 

 division is somewhat localized along the ovarian wall, so that 

 there results here and there a slight swelling. The layer im- 



