104 STRUCTURAL BOTANY 



The petals have no sooner appeared than their growth 

 ceases for a time. Hence we shall find that the next 

 inner whorl, that of the stamens, soon overtakes them. 



The stamens appear in the same order as the sepals, 

 opposite which they arise. First an outgrowth is 

 formed opposite the anterior sepal (Fig. 38, D, sf). 

 It immediately forks into two, and gives rise to the 

 anterior pair of long stamens (E, et a ). Next two 

 papillae are formed opposite the two lateral sepals. 

 These develop into the two short lateral stamens (D 

 and E, st l ). Finally a posterior papilla is formed, 

 which like the anterior one immediately branches and 

 produces the posterior pair of long stamens (D and E, 

 st p and et). 



The pistil is the last part of the flower to be formed. 

 The two carpels appear as two slightly elevated ridges 

 opposite the lateral sepals ; they are only distinct at 

 their very first origin. A zone of tissue underneath 

 their insertion begins to grow up immediately, carrying 

 the carpels up with it, and forming a tubular column 

 in the centre of the flower, on the upper edge of 

 which the original carpels can scarcely be distinguished 

 (Fig. 38, E, cp). On the inside of the carpellary tube 

 two longitudinal ridges arise; the position of these 

 ridges is posterior and anterior, i.e. they come midway 

 between the centre-lines of the two carpels (F and G). 

 These ridges are the placentas, on which the ovules or 

 unripe seeds are borne. Two elevations soon appear 

 on the edge of the carpellary tube just above the 

 placentas. These elevations become the stigmas (F 

 and H, sg), and ultimately close in over the top of the 



