80 



PLANT RELATIONS. 



Fig. 73. A flower of the tobacco plant : a,, a complete flower, showing the calyx with 

 its sepals blended below, the funuelform corolla made up of united petals, and the 

 stamens just showing at the mouth of the corolla tube ; 6, a corolla tube split open 

 and showing the five stamens attached to it near the base ; c, a pistil made up of 

 two blended carpels, the bulbous base (containing the ovules) being the ovary, the 

 long stalk-like portion the style, and the knob at the top the stigma.— After 

 Straseukger. 



last set of floral leaves {carpels) appear, the growth of the 

 stem in length is checked and the cluster of floral leaves 



Fig. 74. A group of flower forms : a, a flower of harebell, showing a bell-shaped 

 corolla composed of five petals ; 6, a flower of phlox, showing a tubular corolla 

 with its five petals distinct above and sharply spreading ; c, a flower of dead-nettle, 

 showing an irregular corolla with its Ave petals forming two lips above the funnel- 

 form base ; t?, a flower of toad-flax, showing a two-lipped corolla, and also a spur 

 formed by the base of the corolla ; e, a flower of the snapdragon, sho'vi^t; the two 

 lips of the corolla closed.— After Gray. 



