334 



HUTCHINSON'S POPULAR BOTANY 



FIG. 406. 

 CROCUS. 



Transverse section 



of ovary showing 



three separate 



chambers. 



which they appear as prominent ridges. Adhesion between 

 stamen (or stamens) and pistil is comparatively rare, but 

 when this consolidation of male with female organs takes 

 place they are called gynandrous, from the Greek gune, a 

 female, and andros, male. 



The fourth and last subject of variation is form. The 

 old idea that the beautiful and oftentimes singular shapes 

 of flowers were designed by the Creator chiefly if not ex- 

 clusively for the pleasure of man has been long discarded 

 by thoughtful minds ; and in the present day one hardly 

 needs to be told that the manifold varieties of floral form 

 are, in the vast majority of cases, so many adaptations for 

 the admission or exclusion of insect visitors, and for facilitating the disper- 

 sion of the pollen. In the zest of what is still, in effect, but a new discovery, 

 many facts relating to this subject have doubtless been distorted, and theories 

 built upon them which will have to be modified or withdrawn ; yet the 

 great central fact remains, and it is one of wide-reaching importance. In 

 succeeding chapters some account will be given of the peculiar contriv- 

 ances by means of which insects are lured to certain flowers and are made 

 the unconscious instruments of pollination ; but at present it is better to 

 direct our attention to typical rather than to special forms. 



It should be further remarked that the subject of Form has particular, 

 though by no means exclusive, reference to the calyx and corolla. Many 

 uses have been enumerated for these floral envelopes. In the earlier stages 

 of the flower they serve as a protection to the delicate cells of the immature 

 stamens and pistil; and at a later period they perform the same kindly 

 offices for the pollen, which might otherwise be blown away prematurely by 

 the wind, or be stolen by unbidden insect guests, or rendered abortive in 

 consequence of injuries from rain and dew. In many plants, again, they 

 assist in bringing about autogamy that is, the fecundation of the flower by 

 its own pollen ; while in others, their powerful odours and vivid colours, 

 by attracting pollen-dusted insects, are instrumental in effecting a precisely 

 opposite result namely, allogamy or fecundation by pollen from another 

 flower. Lastly, the floral envelopes may act as a protec- 

 tion to the nectar, which, though oftenest secreted at 

 the base of those organs, is not infrequently found in 

 hollows and warty projections of the stamens and pistil. 

 Beginning with the outermost floral whorl or calyx, 



let us try to realize, by means of a few examples drawn 

 from familiar flowers, some of the facts to which we have 

 been referring. We can conceive of no easier or more 

 interesting way of acquiring a knowledge of the mor- 

 phology of floral organs than by considering them in 

 relation to the functions which they fulfil. 



FIG. 407. 

 BUTTERCUP. 



Apocarpous fruits. 



