ABOUT THE PETAL. 225 



ages. But observe, these appendages, which generally affect 

 the form of a spur, have no character of generality, Thus, 

 for example, in the violet, a single petal is prolonged into a 

 spur below its point of attachment ; in larkspur, and the other 

 Delphiniums ', there are two which terminate in the same man- 

 ner; in the Aquilegia vulgaris, all the t petals are calcarate 

 (calcar, a spur). 



According as the veins of the petal proceed in a straight 

 or curved direction, its limb may be flat, or concave, or hol- 

 lowed like a boat i.e., cymbiform (cymba, a boat), or naviculate 

 (navis, a ship), or like a spoon, cochleariform (cochleare, a spoon). 

 When the spur is very short, as in Antirrhinum and Valerian, 

 the corolla or petal is termed gibbous (gibbus, a swelling), or 

 saccate at the base. 



If a petal continue narrow, so as to seem formed by the 

 prolongation of the claw, it is called linear', if the limb be 

 prolonged below, so as to form two lobes, it is cordate, as in 

 Genista caudicans ; or if the lobes be acute, it may be sagittate 

 or hastate. 



The number of petals varies from two to twelve, and more. 

 A corolla with a single petal, unipetalous, which we must not 

 confound with the monqpetalous corolla, is a monstrosity, created 

 by defective development; the other petals or foliola are 

 abortive. A corolla with two petals, or dipetalous, as in 

 Circcea Lutetiana, is rare. A tripetalous corolla occurs only 

 when the calyx has likewise three foliola. But in this in- 

 stance opinions are divided : the majority will not admit more 



p 



