29 



plant when the foliage dies down you will find, not a bulb, but 

 an irregular brown tuber, like 

 a small, hard, deformed po- 

 tato, the mass being often 

 made up of two, three, or 

 more parts joined together 

 like the fingers of a hand, or 

 perhaps more like a star-fish. 

 The change, however, from a 

 regularly formed to an irre- 

 gular tuber is not a great 

 one ; and, indeed, if you sow 

 the seed of /. tuberosa, you 

 will find that the product of 

 the first year's, and indeed of 

 the second year's growth, is a 

 small rounded nodule which 

 you would at once say is a 

 bulb; this Iris is a bulb (in 

 the loose sense of the word) 

 when it is a baby, and be- 

 comes a tuber as it grows old. 

 We may probably infer that, 

 though we must now speak of 

 it as a tuberous Iris, it has 

 descended from ancestors 

 which were undoubtedly what 

 we should call bulbous. 



The plant has one very 

 striking feature : the leaf is 

 four-sided, with a horny point, 

 like that of I. reticulata ; in- 

 deed the differences between 

 the leaves of the two plants 

 are relatively small, and a 

 casual observer might easily 

 confound the two. The 

 flower, again, in another fea- 

 ture draws near to a mem- 

 ber of the Eeticulata group, 



FIG. 19. IRIS*TUBEBOSA. (From the 

 Gardeners' Chronicle.) 



namely, I. Danjordia\ the inner segments or standards are 



