A "SIAMKSK TWIN" l*M;WKKIi 



Three plants like this were found jjrowinK in a hack yard. Investigation shows that tliey are 

 sectorial chimeras — plants made up of two kinds of tissue (green and white) which remain 

 perfectly distinct, so that one may describe the i)igwecd as consisting of a white plant and 

 a green plant, each forming part of the whole individual. A streak cm he seen running 

 down tlic main stem of the plant, composed of white tissue like that in the leaves. Many 

 plants with variegated leaves have been studied in recent years, and their surprising 

 manner of heredity exf)lained, partly by mathematical formulas. (Frontispiece.) 



