164 



BOTANY. 



(Apostasiece) , being a small one and unrepresented in the 

 United States. The orchids are in some respects the most 

 highly specialized of all flowers, and exhibit wonderful variety 

 in the shape and color of the flowers, which are often of 

 extraordinary beauty, and show special contrivances for cross- 

 fertilization that are without parallel among flowering plants. 



FIG. 89. Gynandrs&. A, inflorescence of the showy orchis (Orchis spectabilis) , 

 x 1 (Orchidese). B, a single flower, with the upper leaves of the perianth 

 turned back to show the column (x). sp. the spur attached to the lower 

 petal or lip. o, the ovary, x 1. C, the column seen from in front, an. the 

 stamen, gy. the stigmatic surface, x 1. D, the two pollen masses attached 

 to a straw, which was inserted into the flower, by means of the viscid disc (d) : 

 i, the masses immediately after their withdrawal ; n, in, the same a few 

 minutes later, showing the change in position. E, diagram of the flower ; 

 the position of the missing stamens indicated by small circles. 



The flowers are always more or less bilaterally symmetrical 

 (zygomorphic). The ovary is inferior, and usually twisted 

 so as to turn the flower completely around. There are two 

 sets of perigone leaves, three in each, and these are usually 

 much alike except the lower (through the twisting of the 



