164 



MANUAL OF BOTANY 



are produced in certain parts in the progress of their develop- 

 ment. Thus in the Foxglove {fig. 318), the general appearance 

 of the corolla is somewhat bell-shaped, but it is longer than 

 this form, and slightly irregular, and as it has been supposed 

 to resemble the finger of a glove, it has received the name of 

 digitaliform or finger-shaped. In the Speedvi^ell {fig. 319), the 

 coroUa is nearly rotate, but the divisions are of unequal size and 

 shape, hence it may be described as irregularly rotate ; and 

 in the Bed Valerian the corolla is irregularly salver-shamed 

 {fig. 321). 



Appendages op the Corolla. — The coroUa, like the calvx, 

 vifhether polypetalous or gamopetalous, is subject to various 

 irregularities, arising from the expansion or growing outwards 

 FiGf. 320. FrG. 321. 



Fig. 320. Flower of a species 

 ol Valerian (Valeriana), 

 c. Calj'x, adherent to tile 

 ovary, t. Limb o( the 

 calyx rolled inwards. The 

 corolla has a projection 

 towards its base, and is 

 hence said to be gibbous. 



Fig. 321. Plower of the 



Eed Valerian (Centran- 

 thus). The corolla is irre- 

 gularly salver-shaped and 

 spurred at its base. 



of one or more of the petals, or the tube, into processes or 

 appendages of different kinds. Thus in the Snapdragon 

 {fig. 314, 5) and Valerian {fig. 320), the lower part of the tube 

 of the corolla becomes dilated on one side, so as to form a little 

 pouch or sac ; it is then termed saccate or gibbous, this term 

 being used in the same sense as previously described when 

 speaking of the calyx. In other cases, one or more of the 

 petals, or the tube, becomes prolonged downwards and forms 

 a spur, when the petal or corolla is described as spurred 

 or calcarate. Examples of spurred petals or corollas may be 

 seen in the Heartsease, Columbine {fig. 323), Toadflax (;?^. 315), 

 and Bed Valerian {fig. 321). Only one spur may be present, as 

 in the Heartsease, or^ each of the petals may be spurred, as in 

 the Columbine {fig. 323). The Yellow Toadflax, which usually 

 produces only one spur, in rare instances is found with five. 



