NOMENCLATURE OF THE FLOWER. 75 



a. Perianth of the flower when it includes the stamens and not 

 the germen, as in the barren flowers of the perennial mercery. 



b. Perianth of the fruit if it includes the germen but not the 

 stamens, as in the fertile flowers of the perennial mercury. 



c. Perianth of the fructification when it includes both the ger- 

 men and stamens, as in the common bramble and others. 



10. Duration: From the time which a perianth 

 lasts, it is either caducous, deciduous, or permanent. 



a. Caducous when it falls off at the first opening of the flower, 

 as in the poppy. 



b. Deciduous when it falls off with the corolla, as in the ber- 

 berry. 



c. Permanent when it continues until the fruit is ripe, as in the 

 dead-nettle, betony, and others. 



FENCF OR JMVOLUCRUM. 



11. The fence or involucrum, is only characterized 

 according to the part of the umbel from which it is 

 placed, or from the number of leaves by which it is 

 constituted. In these respects, it is said to be universal, 

 partial, and dimidiate; and, one-leaved, two-leaved, 

 three-leaved &c. 



a. Universal when situated at the base of the whole umbel, as 

 in the coriander. (F. 14, a a.) 



b. Partial when placed under each smaller or partial stalk, as 

 in the carrot. (F. 14, b b.) 



c. Dimidiate when it is deficient on one side, as in the fool's 

 parsley. 



CATKIN OR AMENTUM. 



12. The catkin or amentum, differs only in two par- 

 ticulars ; iu form and nature. 



