SECT. 1. ORGANOGRAPHY AND GLOSSOLOGY. 95 



the petals, which are free, and project beyond the 

 margin. 



3. Irregular polypetalous Corollce. 

 One of the most prominent of 

 this class is the " papilionaceous" 

 flower (fig. 94.), composed of five pe- 

 tals ; which, however, are not always 

 free at their base ; but in a few cases 

 cohere by their claws into a tube. 

 The large single petal is termed the 

 ic standard" (a) ; the two lateral, the 

 "wings" (6); and the two others, 

 which often cohere into one, form the 

 " keel " (c). These flowers belong ex- 

 clusively to certain groups of the 

 extensive order " Leguminos*," of which beans and 

 peas are familiar examples. 



There is a vast variety among the irregular poly- 

 petalous corollae, originating in peculiarity of shape, 

 and in the proportion and numbering of the several parts. 



(96.) Glumaceous Flowers. The grasses ( Graminece) 

 and sedges (Cyperaceai) have their flowers constructed 

 in so peculiar a manner, that it will be necessary to 

 describe them somewhat more particularly. Their peri- 

 anth consists of membranous scales termed " glumes," 

 which are referable to a modification of bracteae, rather 

 than of those more or less 

 flaccid and foliaceous organs, 

 which we have described as 

 sepals and petals. In the 

 example selected for fig. 95., 

 there is a pistil (a), com- 

 posed of an ovarium which 

 contains a single ovule> and 

 is surmounted by two 

 stigmas. At the base are two 

 scales. There are three sta- 

 mens. These parts are in- 

 cluded between two glumes (6), one of which is towards 



