3 i 4 CHAPTERS ON EVOLUTION. 



than the circlets or whorls of leaves which, in the form of calyx and 

 corolla, surround and protect them. Yet the latter organs play their 

 own part in the production of seeds, and in some cases serve as the 

 actual means whereby special modes of fertilisation are primarily 

 induced and carried out. As the sequel may show, indeed, the 



FIG. 216. STAMENS 

 OF IRIS. 



FIG. 217. STAMEN OF 

 AMARYLLIS. 



FIG. 218. PISTIL OF 



CHINESE PRIMROSE. 



calyx and corolla which in previous years were deemed mere 

 "floral envelopes," being credited, as such, with a merely protective 

 function have largely risen in importance in the estimation of the 

 botanical world ; since on the form, colour, size, 

 &c., of the corolla especially, largely depend the 

 working of those mutual relations which have 

 been formed between the insect-world on the one 

 hand, and the world of flowers on the other. 

 Peculiarity of a corolla implies, botanically, as a 

 rule, peculiarity of fertilisation ; and the impor- 

 tance of the blossom becomes plainly apparent 

 to us when we discover that in place of the 

 somewhat limited function formerly assigned to 

 it by the unscientific philosopher namely, that of affording delight 

 to man by its beauty it subserves the truer and more logical mission 

 of aiding materially the increase of the race to which it belongs, and 

 of which it forms such a characteristic part. 



Turning to the primrose for practical illustration of the foregoing 



FIG. 219. STRAWBERRY. 



