WATER-POKES. 89 



The water-stomata are found in the upper side of the leaf, and 

 always over the ends of the principal veins. Here the edge of 

 the leaf tends to show r a small depression. A general idea of 

 the water-stomata can be obtained if a suitable piece of a 

 leaf in its entire thickness is brought into the field of the 

 microscope, under water, and covered with a cover-glass, though 

 the details are only observable on surface-sections taken from 

 a suitable part of the edge of the leaf. A water-stoma then 

 presents the appearance in Fig. 32. The dead contents of the 

 guard-cells are as a rule very greatly reduced. Several water- 

 stomata are usually found grouped at a short distance from one 

 another. 



Water-Pores of Fuchsia. Another favourable object for the 

 study of these water-pores is the Fuchsia 1 but preparation is 

 somewhat more difficult, as the stomata are only found at the 

 apex of the teeth on the leaf margin. The sections must there- 

 fore be taken 'through these. The guard-cells here show living 

 contents, and a fair number of chlorophyll bodies. Thick sec- 

 tions can be made transparent with potash. 



