126 BOTANY. [chap. iv. 



agency of insects, is due the evolution of those parts of 

 the reproductive structure possessing colour — usually 

 the corolla— ^scent, and nectar. 



The typical flower of a phanerogamic plant, as shown 



Fig. 34. Fuchsia glohosa, a Phanerogamic plant with a complete 

 flower, that is, having the four whorls, calyx, corolla, stamens, and 

 pistil present. (Natural size.) 



in the diagramic representation on p, 31, consists of four 

 whorls or verticils, the lowest on the axis or flower-stalk, 

 and outermost is the calyx, function protective; next the 

 corolla, function attractive, in the sense of acting as a 

 coloured advertisement indicating to insects the where- 



