i8o 



GROWTH AND WORK OF PLANTS 



mental foliage, while in some others the spathe is brightly 

 colored, as in the calla lily (Richardia) , which is not a true 

 lily. Another very interesting member of this family is the 

 skunk cabbage, so called because of its peculiar odor and large 

 cabbage-like leaves. Both kinds of flowers are borne on the 

 same spadix, which is club-shaped. 



Gladiolus. 



287. The showy flowers of gladiolus arise in two ranks 

 on a long terminal shoot, but they bend to one side, giving 

 the appearance of a long unilateral spike, which sometimes has a 

 slight tendency to a spiral form. The base of the flower is 



Fig. 135- 



Flowers of Gladiolus; at right, 

 partly dissected. The six petal - 

 like parts form, the "perianth." 



covered by two leaf-like bracts. The showy part of the flower 

 is the perianth, but, unlike the lily, the six parts of the perianth 

 are united toward the base into a tube, which is attached to 

 the upper part of the ovary, and the lower part of the tube is 

 coalesced with the outer part of the ovary. The parts of the 

 perianth are somewhat irregular, so that it has in some varieties 

 a decidedly two-lipped appearance. The upper petal (upper lip) 

 is usually covered by the two lateral sepals, while the two 

 lower petals are covered by the lower sepal and the two lateral 

 ones. 



