SECTION 8.] MODIFICATIONS OF THE TYPE. 



91 



Tubular ; when prolonged into a tube, with little or no spreading at the 

 border, as in the corolla of the Trumpet Honeysuckle, the calyx of Stra- 

 monium (Fig. 246), etc. 



261. Although sepals and petals are usually all blade or lamina (123), 

 1'ke a sessile leaf, yet they may have a contracted and stalk-like base, an- 

 swering to petiole. This 

 is called its CLAW, in 

 Latin Unguis. Unguicu- 

 late petals are universal 

 and strongly marked in 

 the Pink tribe, as in 

 Soapwort (Fig. 248). 



262. Such petals, and 

 various others, may have 

 260 an outgrowth of the in- 



ner face into, an appendage or fringe, as in Soapwort, and in Silene (Fig. 

 259), where it is at the junction of 

 claw and blade. This is called a 

 CROWN, or Corona. In Passion- 

 flowers (Fig. 260) the crown consists 

 of numerous threads on the base of 

 each petal. 



263. Irregular Flowers may be 

 polypetalous, or nearly so, as in the 

 papilionaceous corolla; but most of 

 them are irregular through coales- 

 cence, which often much disguises 

 the numerical symmetry also. As 

 affecting the corolla the following 

 forms have received particular names : 



264. Papilionaceous Corolla, 

 Fig. 261, 262. This is polypetalous, 

 except that two of the petals cohere, 

 usually but slightly. It belongs only 

 to the Leguminous or Pulse family. 

 The name means butterfly-like; but 

 the likeness is hardly obvious. The 

 names of the five petals of the 

 papilionaceous corolla are curiously 

 incongruous. They are, 



FIG. 259. Unguiculate (clawed) petal of a Silene; with a two-parted crown. 

 FIG. 260. A small Passion-flower, with crown of slender threads. 

 FIG. 261. Front view of a papilionaceous corolla. 262. The parts of the same, 

 displayed: s, Standard, or Vexillum; w, Wings, or Alae; k, Keel, or Carina. 



