Wild-Flower Study 



531 



yellow; pushing up be- 

 tween two of the sepals, 

 which clasp tips beyond 

 it, there appears a row 

 of petals. Then some 

 warm evening, usually 

 about sunset, but vary- 

 ing from four o'clock in 

 the afternoon to nine or 

 ten in the evening, the 

 petals begin to unfurl; 

 they are wrapped around 

 each other in the bud as 

 an umbrella is folded, 

 and thus one edge of 

 each petal becomes free 

 "first. The petal first in 

 freeing its edge seems to 

 be doing all the work,. 

 buc we may be sure that 

 all the others are push- 

 ing for freedom; little 

 by little the sepals are 

 pushed downward, until 

 their tips, still clasped, 

 are left beneath; and 

 the petals now free, sud- 

 denly flare open before 

 our delighted eyes, with 

 a movement so rapid 

 that it is difficult for us 

 not to attribute to them 

 consciousness of action. Three or four of these flowers may open on a 

 plant the same evening; and they, with their fellows on the neighboring 

 plants, form constellations of starry bloom that invite attention from the 

 winged creatures of the twilight and the night. There is a difference in 

 the time required for a primrose flower to unfold, probably depending 

 upon its vigor; once I watched for half an hour to see it accomplished, 

 and again I have seen it done in two or three minutes. The garden 

 species seems to unfold more rapidly than the wild species, and is much 

 more fragrant. The rapidity of the opening of the blossom depends upon 

 the petals getting free from the sepals, which seem to try to repress them. 

 The bud is long, conical, obscurely four-sided, and is completely covered 

 by the four sepals, the tips of which are cylindrical and twisted together; 

 this is an interesting habit, and one wonders if they hold the petals back 

 until the latter are obliged to burst out with the force of repressed 

 energy; after they let go of the petals, they drop below the flower 

 angularly, and finally their tips open and each sepal turns back length- 

 wise along the seed-tube. 



The four lemon-yellow petals are broad, with the outer margin 

 notched. The eight stamens are stout, and set one at the middle of each 

 petal and one between each two petals. The long, pale yellow anthers 



1 7 



I, Evening primrose, showing buds, one ready to open, 

 a flower just opened above at the left, an older 

 flower at the right, a fading flower and seed- 

 capsules below. 2, Seed-capsules. Cross section 

 of seed-capsule with seeds above. 



