250 Notes on (Enothci'a. [zoe 



leaves ought to have no weight. They both have white shreddy 

 stems, CE. irichocalyx being more frequently red than white. The 

 flowers and capsules do not differ sufficiently to be marked. From 

 all these considerations I feel compelled to believe that there is but 

 one species instead of two. I have not had opportunities to observe 

 the habits of any of these forms, but all are white -flowered and of 

 course open in the evening. 



Oenothera coronopifolia Torr. & Gray. Next to CE. biewiis, this 

 seems most widely distributed. The flowers have a strong, sicken- 

 ing odor, and open before sunset. The style which is at first erect 

 and longer than the stamens becomes declined as in Epilobium 

 spicatum. It is not fertilized in the bud. The flowers remain open 

 until nearly noon the next day and seem to gradually wither, 

 changing from white to rose color. They are not quite an inch in 

 diameter, and often there are several in bloom at once on the low 

 but erect stem. There are two rows of seeds in each cell as in 

 those of CE. pinnatifida. 



CEnothera ccespitosa Nutt. , is the most variable of all the species, 

 especially in its manner of growth, seeming to change so as to 

 adapt itself to different conditions, or rather those that became best 

 adapted prevailed and transmitted their qualities to the new genera- 

 tions. The form from Steamboat Springs in Routt county, Colorado, 

 has pods on peduncles from a half-inch to an inch long. It is caes- 

 pitose. I have not seen the flower. The Mancosform is csespitose 

 from running root -stocks, with slightly angled sessile pods. The 

 petals are deeply obcordate. At Grand Junction there are three 

 forms: first, the typical caespitose form; second, that with simple erect 

 stem, the flowers in the axils and the dry stem of winter thickly 

 covered with large ridged- winged sessile pods; and third, the inter- 

 mediate, with stems branching from the base above ground, instead 

 of underground, as in the Mancos form. The first is the common 

 mountain form, the second is found at Pueblo and near Colorado 

 Springs in the same kind of adobe soil in which it lives at Grand 

 Junction. The axis of the two last forms is succulent, and doubt- 

 less holds a supply of moisture to ripen the fruit during the dry 

 season that always follows the spring rains. The capsules are 

 strongly winged and sessile. The flowers of this species are not 

 fertilized in the bud. I watched the Mancos form and found that 

 the flowers expanded almost at sunset, quite gradually but notice- 



