164 



THE FLOWER. 



or pattern, and especially some one which is both complete and 

 morphologically simple. 



295. Such a flower consists of two kinds of organs, viz. the 

 Protecting Organs, leaves of the blossom, or floral envelopes, 

 which, when of two sets, are CALYX and COROLLA ; and the 

 Essential Reproductive Organs, which co-operate in the production 

 of seed, the STAMENS and PISTILS. 



296. Floral Envelopes, Perianth, or Perigone, the floral leaves 

 or coverings. The former is a proper English designation of 

 these parts, taken collectively. But in descriptive botany, 

 where a single word is preferable, sometimes the name perianth 

 (Lat. perianthium) , sometimes that of perigone (or perigonium) , 

 is used. Perianthium, 1 a Linnsean term, has been objected to, 

 because it etymologically denotes something around the flower ; 

 but it seems not inappropriate for the envelopes which surround 



the essential part of the flower. Perigonium, 

 a later term, has the advantage of meaning 

 something around the reproductive organs, 

 which is precisely what it is. Neither name 

 is much used, except where the perianth or 

 perigone is simple or in one set (when it is 

 almost always cah^) , or where it is of two 

 circles having the gen- 

 eral appearance of one 

 and needing descrip- 

 tive treatment as such, 

 as in the petaloideous 

 Monocotyledons. It is 

 also used where the 

 morphology is ambigu- 

 ous. Generally, the floral envelopes are treated distinctively as 

 calyx and corolla, one or the other of which (mostly the corolla) 

 may be wanting. 



297. The Calyx is the outer set of floral envelopes. That is 

 its only definition. Commonly it is more herbaceous or foliaceous 

 than the corolla, and more persistent, yet sometimes, as in the 

 Poppy family, it is the more deciduous of the two. Not rarely it 



1 Linnaeus (and about the same time Ludwig) used it in the sense of a 

 proper calyx, yet with some vagueness. Mirbel and Brown established it 

 in the sense of the collective floral covering. DeCandolle revived Ehrhart's 



PIG. 307. The complete flower of a Crassula. 308. Diagram of its cross-section in 

 the bud, showing the relative position of its parts. The five pieces of the exterior 

 circle are sections of the sepals; the next, of the petals; the third, of the stamens 

 through their anthers; the innermost, of the five pistils. 



FIG. 309. A sepal; 310, a petal; 311, a stamen; and 312, a pistil from the flower 

 represented in Fig. 307. 



