HAIRS ON THE LEAF. 



17 



with a root-hair. They usually point to the apex of a leai or 

 stem, but in Leersia (rice-cut grass), they point downward, 

 and become stout supporting hooks. 



Tragus racemo- 

 s us, A mphicarp u m 

 Pursldi, P ani- 

 cum capillare 

 (hair grass) and 

 others, have stout 

 hairs on the mar- 

 gins of the leaf. 

 On some smooth 



Ipflvoc +Tio liairc FlG - 19. Part of a cross section of Melica strfcto, showing 

 leaves, tJ nairs, niany stiff hairs. 1x34. (Sudworth.) 



when young, drop off and leave scars which alternate with the 

 larger cells of the epidermis. 



Bulliform Cells. We will now consider more in detail the 

 bands of bulliform (blister) cells which are larger than other 

 cells of the epidermis, and have thinner walls. They have also 



