STRUCTURAL BOTANY. 



[35. 



six-leaved perianth ; each leaf gradually spreading so 

 as to resemble, as a whole, the funnel-form (58). 



101. Polypetalous-irregular forms (59, 71) may gen- 

 erally be referred to these two types the papiliona- 

 ceous and the orchidaceous. The Papilionaceous (pa- 

 pilio, butterfly) corolla or flower may consist of five 

 dissimilar petals, designated thus : the upper, largest, 

 and exterior petal is the banner (vexillum) ; the two 

 lateral, half-exterior, are the wings (alee) ; the two 

 lower, interior petals, often united at their lower mar- 

 gin, are the keel (carina). The flowers of the Pea, 



59, Papilionaceous flower of the Pea, 60, Displayed: v, the vexillum; a, a, the alae; c, c, the carina. 

 61, Section of flower of Dicentra Cucullaria. 



Locust, Clover, and of the great family of the Legu- 

 minosse in general are examples. The Orchidaceous 

 is a form of the perianth peculiar to the Orchis, and 

 to that large and singular tribe in general. It is a 

 6 -parted double perianth, very irregular, characterized 

 chiefly by its lip, which is the upper petal (lower by 

 the twisting of the ovary) enlarged and variously 

 deformed. 



102. Gamopetalous-regular perianths (62-67) may 

 include mainly the following forms, although some of 

 them may become irregular. First, Rotate, wheel- 

 shaped ; or star-shaped, is a form with tube very short, 



