20 SALVIA. [CHAP. 



with them. The row of small hairs at the bottom of 

 the tube prevents small insects from creeping down 

 the tube and stealing the honey. Lastly, the small 

 processes on each side of the lower lip are the rudi- 

 mentary representatives of parts, formerly more largely 

 developed, but which, having become useless, have 

 almost disappeared. 



In the Deadnettle, it would appear that the pistil 

 matures as early as the stamens, and that cross-fertili- 

 sation is attained by the relative position of the stigma, 

 which, as will be seen in the figure, hangs down below 

 the stamens ; so that a bee, bearing pollen on its back 

 from a previous visit to another flower, would touch 

 the pistil and transfer to it some of the pollen, before 

 coming in contact with the stamens. In other species 

 belonging to the same great group (Labiatse) as La- 

 mium, the same object is secured by the fact that the 

 stamens come to maturity before the pistil ; they shed 

 their pollen, and shrivel up before the stigma is mature. 



Fig. 14 represents a young flower of Salvia officinalis 

 in which the stamens {a a) are mature, but not the 

 pistil (/), which, moreover, from its position, is un- 

 touched by bees visiting the flower ; as shown in 

 Fig. 15. The anthers, as they shed their pollen, 

 gradually shrivel up ; while, on the other hand, the 

 pistil increases in length and curves downwards, until 

 it assumes the position shown in Fig. 16, st, where, as 

 is evident, it must come in contact with any bee 

 visiting the flower, and would touch just that part of 

 the back on which pollen would be deposited by a 

 younger flower. In this manner cross-fertilisation is 

 effectually secured. 



