92 



FLOWERS. 



[SECTION 8. 



The Standard or Banner (Vexillum), the large upper petal which is 

 external in the bud and wrapped around the others. 



The Wings (Ala), the pair of side petals, of quite different shape from 

 the standard. 



The Keel (Carina), the two lower and usually smallest petals ; these are 

 lightly coalescent into a body which bears some likeness, not to the keel, 

 but to the prow of a boat ; and this encloses the stamens and pistil. A 

 Pea-blossom is a typical example ; the present illustration is from a species 

 of Locust, Robinia hispida. 



265. Labiate Corolla (Fig. 256-258), which would more properly have 

 been called Bilabiate, that is, two-lipped. 

 This is a common form of gamopetalous co- 

 rolla ; and the calyx is often bilabiate also. 

 These flowers are all on the plan of five ; 

 and the irregularity in the corolla is owing 

 to unequal union of the petals as well as to 

 diversity of form. The two petals of the 

 upper or posterior side of the flower unite 

 with each other higher up than with the 

 lateral petals (in Fig. 256, quite to the top), 

 forming the Upper lip : the lateral and the 

 lower similarly unite to form the Lower lip. 

 The single notch which is generally found 

 at the summit of the upper lip, and the two 

 notches of the lower lip, or in other words 

 the two lobes of the upper and the three of 

 the lower lip, reveal the real composition. 

 So also does the alternation of these five 

 parts with those of the calyx outside. When 

 the calyx is also bilabiate, as in the Sage, 

 this alternation gives three lobes or sepals 

 to the upper and two to the lower lip. Two 

 forms of the labiate corolla have been desig- 

 nated, viz. : — 



Bingent or Gaping, when the orifice is 

 wide open, as in Fig. 256. 



Personate or Mashed, when a protube- 

 rance or intrusion of the base of the lower 

 lip (called a Palate) projects over or closes 

 the orifice, as in Snapdragon and Toad-Flax, Fig. 25 7, 258. 



Fig. 263. Corolla of a purple Gerardia laid open, showing the four stamens ; the 

 cross shows where the fifth stamen would be, if present. 



Flo. 264. Corolla, laid open, and stamens of Pentstemon grandiflorus, with a 

 sterile filament in the place of the fifth stamen, and representing it. 



Fig. 265. Corolla of Catalpa laid open, displaying two enod stamens and three 

 abortive ones or vestiges. 



