352 Miscellaneous. 



last of an old race is as conceivable as that it is the first of a new 

 one. An attentive study of the Begonia and a careful perusal of 

 Darwin's book will, I am sure, convince your readers that this varia- 

 tion is a fact after that author's own heart. The fact of a meta- 

 morphosis so simple and common as that of stamens into carpels, 

 suggesting to a first-rate botanist a new view of the affinity of the 

 plant in which it occurs, is a very frequent one, and shows the im- 

 perfection of our knowledge and systems, not the magnitude or im- 

 portance in the abstract of the changes that affect them. Instead 

 of this being a case which (according to Dr. Harvey) " was not con- 

 templated by Mr. Darwin's hypothesis," it is one of a class which 

 he had specially in view ; it is a beautiful illustration of the truth 

 and wisdom of his chapter on classification, in which he shows how 

 false are often the standards by which we estimate the value of cha- 

 racters ; how loaded by preconceived ideas is the balance in which 

 we weigh them ; how prone, in short, we are to assume that a change 

 is in itself fundamental, because it shakes our systems to the foun- 

 dation. The differences between the extreme forms of the Begonia 

 flowers are in no way comparable to those between " an elephant 

 and a rhinoceros ; " nor do they lead us to imagine that the latter 

 could ever be the progeny of the former. According to Darwin's 

 hypothesis, the change from species to species must be slow, and is 

 effected by the accumulation of small differences ; this Begonia, as- 

 suming it to be the herald of a new type of Begoniacese, is a good 

 instance of how slow and partial such a change is at the commence- 

 ment ; for it is confined to one set of organs in a very few flowers of 

 one sex only, is conducted with the least possible disturbance of the 

 functions of the plant, and there are prodigious odds against its ulti- 

 mate success. We cannot indeed conceive the new form replacing 

 the old till after the lapse of many generations, and a long course of 

 that operation of natural selection which my friend thinks his forth- 

 coming new type of Begoniaceae has already dispensed with. Lastly, 

 Dr. Harvey makes a most ingenious use of the abnormal flowers of 

 the Begonia in seeking the affinity of the curious order to which it 

 belongs ; and assumes that it tends to place Begoniacese in the 

 same alliance with Aristolochieee and others, because it too includes 

 genera with a superior and an inferior fruit ; but amongst the many 

 orders that share this peculiarity of the Begonia there is one much 

 nearer to the position assigned to it (by Lindley first and by common 

 consent since), and that is the alliance of Saxifrages : in these, and 

 often in the same genus, we have superior and inferior ovaries *, free 

 and connate carpels, with several modifications of placentation, 

 epigynous, perigynous, and hypogynous stamens, the peculiar 

 ovules of Begonia, its remarkable seeds, and its reticulated testa. 

 Finally, to the same group also belongs Sempervivum, which offers 

 another most curious instance of the conversion of stamens into 

 carpels. Gardeners' Chronicle, Feb. 25, 1860. 



* I need hardly remind the botanical reader that the conversion of stamini- 

 ferous into pistilliferous flowers in unisexual trees is not uncommon, and that 

 free superior carpels occur in species whose ovaries are normally inferior. 



