LEAVES. 



[SECTION 7. 



by sticking fast to very viscid glands at the tip of strong bristles, aided 

 by adjacent gland-tipped bristles which bend slowly toward the captive. 

 The use of such adaptations aud operations may be explained in another 

 place. 



3. STIPULES. 



174. A leaf complete in its parts consists of blade, leaf-stalk or petiole, 

 and a pair of stipules. But most leaves have either fugacious or minute 

 stipules or none at all; many have no petiole (the blade being sessile or 

 stalkless) ; some have no clear distinction of blade and petiole ; and many 



of these, such as those of the Onion aud 

 all phyllodia (1 66), consist of petiole only, 

 175. The base of the petiole is apt to 

 be broadened and flattened, sometimes 

 into thin margins, sometimes into a sheath 

 which embraces the stem at the point of 

 '} attachment. 



178 



180 



170. Stipules are such appendages, cither wholly or partly separated 

 from the, petiole. When quite separate they arc said to be free, as in Fiu r - 

 1 1 2. AVhen attached to the base of the petiole, as in the Rose and in 



Fiu. 1 77. Leaf of Red Clover: st, stipules, adhering to the base of p, the petiole; 

 b, lilade of three leaflets. 



KM;. 17*. Part of stein and leaf of Frince's-Feather (Polygonum orii-ntaK') with 

 the united sheathing stipules forming a sheath or ocrca. 



Flo. 179. Terminal winter hud of Magnolia Umbrella, natural size. 180. Outer- 

 most bud-scale (pair of stipules) detached. 



