212 MARSH PLANTS 



lipped structure. The corolla has also a short spur, 

 and often two yellow spots on the lower lip. But 

 there are only two stamens, and the ovary has only a 

 single compartment, in which the seeds are arranged 

 in much the same manner as in the Primroses and 

 Androsaces. 



But we are not concerned here so much with the 

 flower as with the leaves of this very interesting plant. 

 If we examine the pale, yellowish-green leaves of the 

 rosette, we shall find that they are sticky on the upper 

 surface. This stickiness results from the presence of 

 numerous glands, or secretory organs, arranged on the 

 upper surface of the leaf. These glands secrete a 

 viscid fluid, which plays an important part in the 

 economy of the plant, as we shall see. By their 

 means it obtains part of its food-supply. Many of 

 the leaves will be found to be concave, for the edges 

 curve somewhat inwards and upwards towards the 

 centre of the leaf. 



A cross-section of a leaf is shown in Text-fig. 

 XIX., 1. On the upper surface, two kinds of glands 

 will be seen, some which are stalked and others which 

 are stalkless, the latter being the more numerous. In 

 Text-fig. XIX., 3, a surface view of one of the stalk- 

 less glands is seen, while Text-fig. XIX., 2, shows a 

 side view of the same. Both of these are highly 

 magnified under the microscope. The glands them- 

 selves can, however, be made out by examining the 

 upper surface of a leaf with a powerful hand-lens. 



Kerner states that there may be as many as 25,000 



