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JOURNAL OF THE 110 YAL HORTICULTURAL SOCIETY. 



and colour so that the whorl is irregular. The former was the primitive 

 form of flowers, and the latter is derived from them in special adaptation 

 to some particular insect or insects which have habitually visited the 

 flowers. 



Floral Degradations. — These are evident in the loss of parts of 

 flowers, in the presence of rudimentary organs, kc. Such imply adapta- 

 tions to wind-pollination or to s elf -pollination, from a previous condition 

 of insect-pollination. 



IV. Pollination of Flowees. 



The meaning of the structures of flowers described in the last lecture 

 is pollination. Everything conspires to secure that " end." 



Flowers are pollinated by means of insects, occasionally birds or water, 

 by " self," i.e. by the pollen of the same flower, and by the wind. 



Flowers pollinated by insects require some attractiveness ; such is 

 usually secured by their being white or coloured (other than green), or by 

 scent. 



The colour is usually situated in the corolla, but it may be in the 

 bracts, as in the scarlet flowers of some of the Cactacece, Salvias, 

 Darwinia, ' Everlastings,' and in the white ones of Cornus. 



The sepals may be white or coloured as in Clematis, Hellebores, 

 Marsh Marigold, Aconite, Anemone, and Larkspur. 



Occasionally the stamens render the flower conspicuous, as of Tha- 

 Uctrum and the catkins of the Sallow Willow. 



Following the order of headings in the last lecture as examples of 

 freedom among the parts of flowers, one may compare the Buttercup, 

 having a regular flower, with Aconite, which has an irregular one. Or, 

 again, Geranium with Pelargonium. 



In the first pair, of the family Banunculacece, it is the petals in 

 which "nectaries" with honey are formed. In the latter, it is the 

 receptacle which has glands (five in Geranium, and one, a long tube, in the 

 floral receptacle).* 



Of flow T ers with coherent petals, there are many regular, as the Heath, 

 while others, as all of the orders Scrophularinece and Labiatce, are 

 irregular. 



Of flowers with " inferior " ovaries, i.e. such as are included in adherent 

 receptacular tubes, the Canterbury Bell with its regular flower may be 

 compared with Lobelia of the same family, which is irregular, or the 

 Daffodil with Orchis. 



In all irregular flowers a number of special structures occur which 

 will soon be observed to be all "additions," so to say, with the object of 

 adapting the (lower more specially than is the case of regular flowers. t 

 Regular flowers are almost always "terminal" at the ends of shoots, so 

 thai they can be visited from all points of their circumference. This 



* I have illustrated the distribution of the fibro-vascular cords, showing the origin 

 of this "axial nectary," Journ. Lmn. Sue, Hot. xxviii. pi. 20, fig. 17 (3). 



f Tin- special peculiarities both oi' regular and irregular Mowers in adaptations to 

 injects have been so abundantly described that it would be needless to repeat them 

 here. The reader is referred to Darwin's Fertilisation of Orchids, Forms of 

 l-'lmn , s. and Cross and Self- Fertilisation of Plants, Midler's Fertilisation of J'lan's, 

 and the writer's Origin of Floral Structures. 



