2 THE BOOK OF THE IRIS 



no cell divisions). Above the ovary is a tube, but this 

 is sometimes so short that it must be regarded as 

 obsolete. There are six perianth segments ; the three 

 outer, known as the "falls," are usually reflexed and 

 have often a very characteristic feature in the possession 

 of a beard, but this may be absent, or, in its place, there 

 may be a crest. The three inner segments differ in 

 form from the outer segments and are known as the 

 " standards " ; they have usually neither beard nor crest, 

 are usually erect, and have always a stalk. The stamens 

 are inserted at the base of the falls, the anthers are 

 attached by their bases, and, as already observed, they are 

 extrorse, i.e. they are turned outwards. This is some- 

 what unusual, but here there is a particular meaning in 

 the fact, which we shall presently notice. They are 

 situated below and sheltered by the arch of the style- 

 arm. There are three style-arms bearing each a lip-like, 

 transverse, terminal stigma, and there are two petaloid 

 crests or appendages to each. Succeeding the flower 

 we have a trigonal or hexagonal capsule, which is some- 

 times beaked, and it contains seeds that are more or less 

 globose. 



Leaving these dry details which, however, may not 

 be dry if the reader will examine the flower itself we 

 may turn to matters of great interest and importance. 

 Let us ask first of all, What is the meaning of a showy 

 flower like this ? As in the case of every other flower, 

 its object, of course, is to produce seed, but as to its 

 showiness we can only say that it has no meaning except 

 in connection with insects. Pollen must be carried from 

 one flower to another, and the insects must not only be 

 rewarded by the honey they get, but they must also be 

 attracted. About this necessity of cross-pollenation, as 

 it is called, there is much discussion, but, to prove the 

 point, we have only to observe that plants which have 

 any other means for the transference of pollen never 



