The style is not inserted perfectly perpendicularly upon the top of the ovary, but bends slightly downward from the longitudinal axis of the flower. Professor Todd has overlooked this point in his figure. Throughout the remainder of its course until near the tip it is almost straight. Thus it will be seen that the large stamen and the pistil are placed almost opposite each other on the lower side of the flower. The angle between their incurved ends, which approach within about three mm. of each other, is about seventy degrees, thus causing them to point toward opposite sides of the flower. Thus it will be seen that, since the flowers are arranged alternately on the opposite sides of a simple, bractless raceme, and the tip of the large stamen always points toward the axis of this raceme, the flowers on the opposite sides of the raceme have both the stigma and the pores of the large stamen turned in opposite directions.
Professor Todd says: “The flowers are arranged on simple, bractless racemes which extend in a horizontal position.” The material examined by the writers does not quite agree with this observation, the most of the racemes extending upward at a considerable angle. Ten racemes from different plants were selected at random and their angle above the horizontal taken. From the table, it will be noted that the nearest approach to the horizontal is fifteen degrees above, one raceme is vertical, and the average of the ten is fifty-seven degrees above the horizontal.
| TABLE A. | |
| I | 65° |
| II | 75° |
| III | 45° |
| IV | 90° |
| V | 15° |
| VI | 45° |
| VII | 60° |
| VIII | 80° |
| IX | 50° |
| X | 45° |
| Average | 57° |
The terminal portion of the raceme, bearing the buds, is strongly decurved, so that unopened buds obstruct in no way a clear view of the conspicuous flowers, which thus appear to be terminal. The racemes, when in flower, are so far to the outside that the flowers are very little screened by the foliage, whose dark green background renders them more conspicuous.
The fact that the racemes extend upward at some angle from the horizontal, by bringing the flowers above the foliage, renders them more conspicuous.
The terminology used throughout this paper is the same as that suggested by Professor Todd. Those flowers in which the pistil as a whole extends towards the right hand, facing in the same direction as the flower, will be called right-handed, and those in which the pistil as a whole extends toward the left, left-handed. It will be seen that, since the tips of pistil and large stamen approach each other, as above described, the tip of the pistil in a right-handed flower turns considerably toward the left, and vice versa. The flowers on the right-hand side of the raceme, as we pass out from the central axis of the plant, are always left-handed, and those on the left side, right-handed.
Professor Todd found from the examination of a small series of material that about an equal number of right-and left-handed flowers is produced. He also says: “It is also a fact of observation that the flowers of a cluster on any one branch and opening about the same time are either all right-handed or all left-handed. Any plant, however, if it is at all large, exhibits right-and left-handed flowers in about equal numbers.”
The regularity with which the flowers are divided into the two classes is very striking. Table B shows the condition of ten plants observed at the same time.
| TABLE B. | |||||
| Plant | I | 7 | pistils right-handed, | 7 | left-handed. |
| " | II | 6 | " " | 6 | " |
| " | III | 8 | " " | 9 | " |
| " | IV | 29 | " " | 31 | " |
| " | V | 11 | " " | 7 | " |
| " | VI | 10 | " " | 7 | " |
| " | VII | 10 | " " | 13 | " |
| " | VIII | 3 | " " | 3 | " |
| " | IX | 3 | " " | 2 | " |
| " | X | 6 | " " | 9 | " |
| Total | 10 | 93 | pistils right-handed, | 94 | left-handed. |
So in these ten plants the number of right-and left-handed flowers is practically equal. The greatest difference in the number of the two kinds is seen in number X, where forty per cent. are right-handed and sixty per cent. left-handed.