PAPAVERACEAE 



73 



Kirchner, 'Flora v. Sluttgart,' p. 281; Knuth, 'Bl. u. Insekt. a. d. nordfr. Ins.,' 

 !'• 23.) — The dull purple flowers are coloured blackish-red at the tip. The flower 

 mechanism agrees with that of Corydalis cava. "Owing to the smallness of the 

 flowers, the lateness of the flowering time, and the concealed habitat, insect-visits 

 are few. Warnstorf (Verb. bot. Ver., Berlin, xxxviii, 1896) believes that cross- 

 pollination by bees or humble-bees is barely possible, as forcible removal of the 

 upper petal from the two Lateral ones — which are united at their tip, and enclose 

 the sexual organs — very easily breaks off the style at its base, for it is not elastic 

 and yielding as in Corydalis. According to the same authority (op. cit., xxxvi ; 

 1895), the pollen-grains are whitish, spheroidal, and smooth, with large projecting 

 germinating processes, and 56-62 /x, in diameter. As the flowers, in spite of the 

 scarcity of insect-visits, almost all set fruits even in continuously rainy weather, which 



Fig. 25. Pitinaria officinalis^ L. (after Hildebrand). (l) Flower seen from the side (enlarged). 

 (2) The same after removal of half the upper petal, and depression of the inner ones. 



entirely prevents visits from bees, there can be no doubt that the inevitable automatic 

 self-pollination is effective. 



Visitors. — Herm. Miiller in Westphalia, and myself at Kiel and Fohr, observed 

 the honey-bee visiting the flower and transferring pollen : Warnstorf noticed a humble- 

 bee, but does not mention the species. In Dumfriesshire (Scott-Elliot, 'Flora of 

 Dumfriesshire,' p. 9) a butterfly was observed. 



165. F. capreolata L., and 166. F. parviflora Lam. — Hildebrand (op. cit.) 

 states that the flower mechanism is quite similar to that of F. officinalis, except 

 that the hood is so feebly elastic that after pressure from above, it either does 

 not regain its original position above the sexual organs or does so but slowly. 

 Both species are capable of autogamy. Moggridge noticed a long-tongued bee 

 (Osmia) visiting the variety pallidiflora of F. capreolata Z., which is indigenous 

 in the west and south of Europe. In this case the flowers are white before fertilization, 

 but afterwards become rose-red or even carmine-red. This remarkable change of 

 colour in the fertilized flowers may probably be explained as an adaptation for 

 increasing the conspicuousness of the whole inflorescence, and for enabling the 

 highly specialized visitors to recognize and avoid such flowers as being devoid of 

 nectar. Similar phenomena are met with in Ribes aureum and R. sanguineum, 

 Weigelia rosea, Melampyrum pratense, and others (cf. vol. i, pp. 85-6). 



167. F. spicata DC. — According to Hildebrand (op. cit.), the flower mechanism 

 of this species agrees with those of Corydalis lutea and C. ochroleuca. The column 

 formed by stamens and pistil when liberated from the hood, springs up by the 

 elasticity of the upper filament, and places itself in the sheltering excavation in 

 the upper petal. This species is also fertile with its own pollen. 



