1890.] NATL'UAL SCIKNCKS OF PIirLADKLl'IIIA. 271 



There i.s one salient point in connection with the whole subject 

 worth placing prominently before the student, and which will be 

 found sustained by the most superficial examination, namely : All 

 plants that are arranged for self-pollination are abundantly fertile, 

 and have a great advantage of numbers in the struggle for life, 

 while those that have to depend on external agencies are usually 

 nuich less productive, and even though the progeny may be found 

 to have greater vegetative vigor, or some other element of strength. 

 The influence of numbers is certainly with those which self-fertilize. 

 If Providence is on the side of the strongest battalions, the argu- 

 ment of nature is on the side of self-fertilization. 



It has come to be a rule with the author of this paper, whenever 

 any plant is unanimously productive, to look for and to find arrange- 

 ments for self-fertilization. A few instances of more than usual in- 

 terest, drawn from last summer's experience, are herewith offered. 



Trichostema dichotomuni. — This pretty blue flowered Labiate is 

 well known as " Blue Curls," and is common in sandy places along 

 the Atlantic Sea-board. In man}' Labiates the lips of the cloven 

 stigma remain closed till after protrusion from the flower. Such 

 cases are commonly with those that are classed as arranged for cross- 

 fertilization. In many, however, the lips expand before the flowers 

 are open and receive pollen from their own anthers, which mature 

 simultaneously. In this plant this is the case, and the inner face of 

 the stigma lobes are so bent that they come in close contact with 

 the anthers from the curved up filaments and finally emerge from 

 the flower, as it expands, covered with own-pollen. 



Buddleia curviflora. — Noting that this pretty Japan shrub 

 was enormously fertile, evidences of self fertilization were at once 

 looked for. The narrow tube of the flower is nearly an inch long, 

 the anthers being inserted about the middle, or at half an inch. The 

 ovarium with the pistil occupies about a quai'ter of an inch. The 

 half inch above the anthers is densely clothed with stiff hair, com- 

 j)letely closing the narrow tube. The brush would effectually cleanse 

 an entering proboscis of foreign pollen, or a withdrawing one of the 

 flower's own pollen. But it is not necessary to speculate on what 

 an insect could or might do, for the anthers burst before the flowers 

 open, and cover the whole stigma with abundant pollen. No one 

 examining these flowers can fail to be convinced that they are in- 

 geniously arranged for self-fertilization. As in all cases of flowers 

 with tubular corollas, the humble bees in this region rifle the flower 



