322 



PLANT LIFE. 



bluish-white powder, which can be readily wiped off with the 



fingers, as from the surface 

 of fruits, such as plums or 

 grapes, the leaf of cab- 

 bage, or the stalk of sugar- 

 cane (fig. 366). The in- 

 terior layers of the wall of 

 the epidermis are some- 

 times converted into mu- 

 cilage, which retards the 

 evaporation of water. 

 The sinking of the sto- 

 mata below the general 



Fig. 364. 



Fig. 363. — Stellate hairs of Draba 

 Thomasii, seen from above. 

 Magnified about 50 diam. — 

 After Kerner. 



?IG. 364. — T-shaped hairs of Ar- 

 temisia mutellina. Magnified 

 about 50 diam. — After Kerner. 



FlG. 365. — Shieldlike scales of an 

 oleaster {Elteagnus a>igusti- 

 folia), seen from above. Mag- 

 nified about 50 diam. — After 

 Kerner. 



Fig. 365. 



level (fig. 367), their arrangement in pits (fig. 368) or in 

 grooves (fig. 357), and their restriction to the under side of 

 the leaf (fig. 359) may be looked upon as further epidermal 



