ECOLOGY OF FLOWERS 



369 



III 



25. Yarrow Achillea millefolium Mull. 



26. Oxeye daisy . . . Chrysanthemum Leucanthemum . . . Miill. 



27. Dandelion . . . Taraxacum officinale . . . Mull., Newell. 



IV 



28. Barberry .... Berberis vulgaris Lubbock. 



29. Mountain laurel . Kalmia latifolia Gray. 



30. White clover . 



31. Ked clover . 



32. Locust. 



33. Wistaria . . 



34. Vetch . . . 



35. Pea. . . . 



36. Bean . . . 



37. Ground-nut . 



38. Partridge-berry . 



39. Primrose . * . 



40. Loosestrife . 



41. Milkweed. 



42. Lady's-slipper . 



Trifolium repens Mull. 



Trifolium pratense Mull. 



Robinia Pseudacacia Gray. 



Wistaria sinensis Gray. 



Vicia cracca Miill. 



Pisum sativum Miill. 



Phaseolus vulgaris Gray. 



Apios tuber osa Gray. 



VI 



Mitchella repens Gray. 



Primula grandiflora, P. ojficinalis . Lubbock. 



Ly thrum Salicaria Gray. 



VII 



Asclepias Cornuti , 



VIII 



Cypripedium acaule 



. . Miill., Newell. 



Newell. 



439. Cleistogamous Flowers. In marked contrast with 

 such flowers as those discussed in the preceding sections, 

 which bid for insect visitors or expose their pollen to be 

 blown about by the wind, are certain flowers which remain 

 closed even during the pollination of the stigma. These 

 flowers are called cleistogamous and of course are not 



