272 MEUE LEAVES PEOPAGATE. 



little, so that at last nothing was left but the stems; but it having 

 been observed since, that from the callous matter that came forth at 

 the bottom, both roots and branches shot out, it appears that all exotic 

 leaves may at any time be converted into trees. For this operation I 

 make choice of the months of July, August, and November ; but those 

 who have stoves and greentiouses may perform it even in winter, and 

 in that case they shoot the better in the spring. Those who have a 

 mind to do it in the spring will have some success ; but it is not so 

 very sure, which ought to be chiefly ascribed to the inconstancy of 

 that season.' " 



Although this work was absurd, yet it originated in the 

 discovery that the mere leaves of some plants will grow under 

 special circumstances ; a fact often supposed to be much more 

 rare than it really is. In Professor Morren's French translation 

 of my Outlines of the First Principles of Horticulture, Eochea 

 falcata* is named as producing adventitious buds from the 

 upper side of its leaves ; and the Orange, the Aucuba, and the 

 Fig, as other instances of leaves \yhich will midtiply their 

 species : the power of Bryophyllum to do the same thing is 

 familiar to every one. Echeverias have been remarked to grow 

 immediately from the leaves that naturally fall off even its 

 flower-stalks. Hedwig found the leaves of the Crown Imperial, 

 put into a plant press, produce bulbs from their surface. 

 There is a well-known case of the same effect having been 

 observed in Omithogalum thyrsoideum. Mr. Auguste de 

 St. Hilaire mentions an instance of leaf-buds generated by 

 fragments of the leaves of " Theophrasta," which had been 

 buried by M. Neumann, chief gardener at the Garden of Plants 

 at Paris, and of young Drosera intermedia. Mr. Henry Cassini 

 is said to have seen young plants produced by the leaves of 

 Cardamine pratensis; English botanists know that offsets 

 spring from the margins of the leaves of Malaxis paludosa ; in 

 our stoves we see Ferns of many kinds, especially Woodwardia 

 radicans, propagating themselves by offsets from the leaves ; 

 Mr. Turpin tells us that floating fragments of "Watercress 

 leaves, cut up by a species of Phryganea for its nest, " produce 

 presently from their base, and below the common petiole, at 

 first two or three colourless roots, then in their centre a small 



* See, also, De Candolle's Physiologie Vfig^tale, ii. 672. 



