THE LOWER DICOTYLEDONS. 



811 



Bean) ; the carpels contain each a single ovule, attached to 

 the bottom of the ovary. 



The flower is shallow, accessible to all kinds of insects, 

 which visit it for the abundant pollen as well as for the 

 honey (only slightly concealed by the outer stamens). 

 Examine flowers of different ages ; the outer stamens have 

 shed their pollen (the anthers open at the sides), while the 

 inner ones are still bent over the carpels, covering the 



ANTHER 



STIGMA 

 - STYLE 

 OVARY 



RECEPTACLE 



PETAL fZ^&ffi' NECTARY 



SEPAL 

 Fig. 121. The Parts of a Buttercup Flower. 



The points of insertion of the different parts are diagrammatically represented 

 on the receptacle. 



stigmas, which are not exposed until most of the stamens 

 have moved outwards and have set the pollen free to be 

 carried away by insects. The " male stage " and the 

 " female stage " thus overlap for some time, during which 

 self-pollination is possible, either because the innermost 

 stamens touch the stigmas or by means of small insects 

 crawling over the flowers. 



322. The Bulbous Buttercup (R. bulbostis) is easily distinguished 

 when in flower ; the sepals curve outwards and downwards. The stem 

 is swollen at the base, forming a kind of corm ; the lower leaves are 

 broad and many-lobed, the upper ones have only a few narrow lobes. 

 The Creeping 1 Buttercup (P. repens) has long creeping branches 

 (runners) which grow along the soil and at the "nodes" send roots 

 downwards and shoots upwards. The Meadow Buttercup (R. acris) 

 has neither runners nor a thickened stem -base, its flower-stalks are not 

 grooved (as are those of the other two species), and it is the tallest of 

 British Buttercups, being sometimes more than a yard in height ; the se- 

 pals are, like those of R. repens, spreading, not i eflexed as in R. bulbosv*. 



