524 



The Journal of Heredity 



PROBABLE CHIMERA OF RECENT ORIGIN 



Grapefruit from Florida which has apparently thrown out a section of 

 orange. Such freaks are fairly common in all kinds of citrous fruits, 

 and are sometimes explained as sectorial bud sports or variations. 

 Ajij^arently this fruit is made partly of grapefruit tissue and partly 

 of orange tissue. How did the orange tissue get there? If it was in 

 the bud to start with, having survived from the graft, then this is a 

 real secttjrial chimera. But if part of the grapefruit tissue suddenly 

 changed into orange tissue, then this is not a chimera, in the usual 

 sense of the word, but merely a bud sport or variation. It has 

 frequently been explained as such, although there is not sufficient 

 evidence that grapefruit tissue really can turn into orange tissue, 

 in that way. Granted that it does, the fruit might be considered 

 a spontaneous chimera. (Fig. 3.) 



and some j;rc\v on the lines where these 

 two kinds of tissue came together. 



PRODUCTION OF BLEND. 



The sprouts from tomato tissue j^ro- 

 duccd tomato yilants. The sprouts 

 from nightshade tissue i^roduced night- 

 shade i)lants. But the sprouts which 

 grew from ])oints of union of the two 

 kinds of tissue were neither the one nor 

 the other; they were both! For the 

 first time, graft-hybrids of this type had 

 been exjjcrimentally ]jroduccd. 



In these first chimeras, the glove-and- 

 hand relationshijj (Hd not exist. The 



relationship was like that of the Siamese 

 twins, the two plants existing side by 

 side in the .same stem and leaves, and 

 yet retaining their identity. One side 

 of the stem, with the leaves and flowers 

 a])])ertaining to it, was characteri.sti- 

 cally tomato, the other side was just as 

 indisjjutably nightshade (sec fig. 4, 

 D.MF. and G.). In a cross section of 

 the main stem, each kind of tissue 

 occupies a distinct scginent or sector; 

 these graft-hybrids, therefore, arc known 

 as sectorial chimeras. 



This success did not satisfy Dr. 

 Winkler, and he continued with his 



