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well known from the researches of CLarles I'arwin, a common 

 labnrnnm. We will let Darwin describe the case: "To 

 behold mingled on the same tree tnfts of dingy-red, bright 

 yellow, and pnrple flowers, borne on branches having widely 

 different leaves and manner of growth, is a surprising sight. 

 The same raceme sometimes bears two kinds of fl<iwers, and 

 I have seen a single flower exactly divided into halves, one 

 side being bright yellow and the other purple, so that one- 

 half of the standard petal was yellow and of larger size, and 

 and the other half pnrple and smaller. In another flower the 

 whole corolla was bright yellow but exactly half of the calyx 

 was purple. In another one of the dingy-red wing petals 

 had a narrow, bright yellow stripe on it; and lastly, in 

 another flower, one of the stamens, which had become 

 slightly foliaceons, was half yellow and half purple; so that 

 the tendency to segregation of character of reversion affiecto 

 even single parts and organs. The most remarkable fact 

 about this tree is that in its intermediate state, even when 

 growing near both parent species, it is quite sterile; but when 

 the flowers became pure yellow or purple they yield seed. I 

 believe that the pods from the yellow flowers yield a full 

 complement of seed; they certainly yield a larger number." 

 "On the other hand, we have a clear and distinct 

 account given to Poiteau by M. Adam, who raised the plant, 

 showing that C. Adami is not an ordinary hybrid; but is what 

 may be called a grafted hybrid, that is, one produced from 

 the united cellular tissue of two distinct species. M. Adam 

 inserted in the usual manner a shield of the bark of C. pur- 



pureus into a stock of C. laburnum; and the bud lay dormant, 

 as often happens, for a year; the sheld then produced many 

 buds and shoots, one of which grew more upright and 

 vigorous with larger leaves than the sh oots of C. purpureus 

 and was consequently propagated." 



