1 144 ^^ TEXTBOOK OF THEORETICAL BOTANY 



Fig. II20. — Anemone nemorosa. Whorl of 

 foliose bracts forming remote involucre. 

 (After Le Maoiit and Decaisne.) 



of five parts, which really belongs to the cyme but looks exactly like the 

 calyx of the flower. 



Another well-known example is the cupule or involucre of Coryliis, the 

 Hazel, which consists of a single enveloping leafy structure, developed from 

 the minute bracteole of the individual female flower. In Scabiosa there is a 

 double involucre, for not only is there a whorl of bracts around the inflores- 

 cence, but each individual flower is surrounded by a membranous cup, 

 which, although it arises from the top of the inferior ovary, can be nothing 

 else than an involucre (Fig. 1121). Finally there is the cupule of the Oak, 

 Oiierais, which is at least partly formed of closely imbricated bracts, although 

 we have shown above that it is basically receptacular in nature and not 

 distinguishable from the receptacular cupules found in Lauraceae. 



Perianth or perigone is the name applied collectively to the floral 

 envelope proper, which in the majority of flowers consists of sepals and 

 petals. There is a certain number of flowers, usually small in size, which 

 have no perianth and are called achlamydeous. At one time this condi- 

 tion of the flower was regarded as a mark of relationship and families thus 

 characterized were grouped by Bentham into the class Incompletae. It is, 

 however, fairly certain that the condition is one of reduction and that it has 

 been reached from more than one direction. The group has therefore been 

 broken up in recent classifications. Among families which are typically 



