IRREGULAR FLOWERS 213 



In some cases the irregularity is due to a petal or a 

 sepal being projected downwards as a short or long tube. 

 If about as long as broad, this projecting tube is termed 

 a sac, if several times as long or broad, a spur. 



In TROP^OLUM the Garden-nasturtium, and in 

 IMPATIENS the Balsam, the lower sepal is spurred, 

 projecting downwards in a pointed tube an inch and 

 a half or so long. If the flower-stalk (pedicel) of 

 PELARGONIUM the Garden-geraneum be cut across, 

 a narrow tube will be found in it on the anterior 

 side. This is equivalent to the spur of TROPCLELUM 

 or IMPATIENS, the tubular part of the sepal having 

 become fused with or confluent with the pedicel. 



In VIOLA the Violet and Pansy, and in IONIDIUM, 

 the anterior petal is produced back as a short sac, 

 in which lie two backward projections from the two 

 anterior stamens (see Part II). In many Orchids 

 too, the lower petal is spurred or is saccate. 



5. But in most cases of irregular flowers there is 

 no spur or sac, only the lower petal sare of a different 

 shape to the upper. In some, the lower petals (or 

 the part of the monopetalous corolla which corre- 

 sponds to them) hang down broad and flat, like a 

 tongue, and is termed a lip. The upper petals are 

 generally arched, the whole flower being sometimes 

 like a mouth, with an upper and a lower lip. Such 

 flowers are termed two-lipped. There is one family 

 of plants, in which the flowers are mostly of this 

 kind i.e. distinctly two-lipped. It is therefore called 

 the LABIATE or 'lip-family'. 



The ordinary Sunflower again, consists of a num- 

 ber of small florets massed together in a head, most 



