156 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



occurs in a separate flower from the pistillate or female element 

 but both kinds are produced on one and the same plant. Now this 

 arrangement, of course, necessitates fertilisation by subsidiary 

 means, and this is doubtless accomplished in nature chiefly by 

 insect agency. In glass houses it is mostly effected by hand, 

 and, let it be noted, that this monoecious character of the 

 Begonia has undoubtedly been of immense advantage to the 

 horticulturist, for the fertilisation of the flowers (especially of 

 closely allied species, or of varieties derived from a similar 

 origin) can be effected with certainty, and with such prolific 

 results that not only are progenies obtained very varied in their 

 colours, but a sturdy race has been produced capable of with- 

 standing the vicissitudes of our climate when fully exposed to it 

 for several months in succession. 



The staminiferous and pistillate flowers are also distinguished 

 from each other by the number of their perianth segments, and 

 still more so by the remarkable trigonal and prominently winged 

 ovary of the latter. In the staminiferous flowers the segments 

 in the cultivated forms are usually four, in two pairs arranged in 

 the form of a cross, one pair often smaller than the other ; but 

 exceptions occur even among the cultivated forms, and especially 

 in the small-blooming varieties, in which the staminiferous flowers 

 have sometimes but two opposite petals, and in others the second 

 pair is much reduced in size, and sometimes almost obsolete. 

 The pistillate flowers, on the other hand, have, in the cultivated, 

 species and their hybrids, nearly always five segments of equal 

 size. Eemarkable deviations in the number of floral segments 

 occur in B. octopetala and B. polypetala, two species from the 

 Andes of Peru. 



The effects of cross-breeding or of cultivation, or perhaps of 

 the two causes combined, on the production of male and female^ 

 flowers in Begonias have become evident in recent experience. 

 In the absence of direct observation, w T e may assume that in the 

 wild state the flowers of both sexes are produced in such a pro- 

 portion as to ensure the perpetuation of the plant. Now some 

 remarkable exceptions to this law have recently occurred among 

 the late-flowering hybrids between B. socotrana and varieties of 

 the tuberous group derived from the Peruvian alpine species ; 

 thus the varieties we raised called " John Heal " and " Winter 

 Gem " have not yet been observed to produce female flowers at 



