POLLINATION OF SOME CALIFORNIAN FLOWERS. 103 



of a large bee. Nectar is abundant in the incurved tips of 

 the spurs. The anthers are at first compactly arranged about 

 the column of carpels, but as the filaments lengthen the outer 

 ones recurve so that there is now a column ten lines or so 

 long of loosely arranged anthers, only those at the tip— i. e., 

 those farthest downward, since the flowers are pendent — 

 shedding pollen. The inner filaments gradually straighten 

 and lengthen so that the dehiscing anthers always occupy 

 the end position. During this process the styles also 

 lengthen, but in all the flowers I observed the minute stig- 

 mas at their tips did not mature until they were quite beyond 

 the anthers, and the pollen was nearly or quite gone, so that 

 self-pollination was impossible. Bombns Ccilifornicus visited 

 the flowers frequently for pollen, but would of course 

 only rarely visit those with mature stigmas. I have never 

 seen bees of any sort attempt to obtain the nectar in a legiti- 

 mate way but have seen a large species of Xyllocopa pierce 

 the spurs four or five lines above the tips and so steal the 

 nectar. So the pollination of these flowers by bees is very 

 uncertain. They seem adapted to agents with longer tongues, 

 and I was much gratified to have this theory supported on 

 three different occasions by the visits of humming birds to 

 the flowers. Where these plants grow in masses, judging 

 from experience with other scarlet flowers, I should expect 

 to see them frequently visited by humming birds. 



Argemone hispida, Gray. Very vigorous plants with 

 large, showy flowers are met occasionally in river washes 

 about the valley. I have observed them only in passing. 

 The large and numerous anthers are covered with pollen 

 when the flowers expand. The five stigmatic surfaces are 

 also mature and are not high enough to escape self-pollina- 

 tion, which is sure to occur. But the flowers, although pro- 

 viding no nectar, seem to be favorites with the bees — the 

 ubiquitous Bombus Californicus, particularly, fairly wallows 

 in the pollen and must effect cross pollination as he enters 

 the flowers. The flowers are of short duration, the anthers 

 often falling before noon of the first day. 



