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THE AMEBIC AN NATURALIST [Vol. XLIII 



matophores which develop in it to lose their power of assimilating 

 C0 2 . Subsequent cell division would occasionally throw off cells 

 of pure white, which would give rise to the white tissue. This is 

 only suggested as a mere possibility. That the condition can 

 hardly be caused by the male nucleus itself would seem to be 

 indicated by the fact that descendants of this nucleus must be 

 present in those cells which are pure green. If the white char- 

 acter were carried by the chromosomes, then it would appear that 

 all the green cells would necessarily be affected. There seems to 

 be no question that the white character is cytoplasmic in its 

 nature, and this would account for the fact that it does not fol- 

 low Mendel's law of segregation in the reduction division. The 

 segregation, in fact, occurs in somatic divisions. 



Professor Correns reports another inteivsting study of variega- 

 tion in a recent article, 3 of which the following is a summary. 



Plants deficient in chlorophyll have hitherto been called 

 "aureas." The author now restricts this term to plants which 

 are deficient in chlorophyll but which have the normal amount 

 of yellow-color materials, zanthophyll and carotin. Those defi- 

 cient in all three are termed "chlorinas." Those of the latter 

 type obtained in commerce were found to be dwarf as compared 

 with normal sorts. The leaves and flowers are also relatively 

 smaller. This smaller size is shown to be partly a consequence 

 of deficiency in chlorophyll and the consequent insufficient 

 nourishment of the plant. On the other hand, it is partly due 

 to a specific Mendelian character of dwarfness, and the Men- 

 delian dwarf habit is strictly correlated with small leaves and 

 small flowers. 



The chlorina races are fully constant. Variegated races have 

 spots of green on leaves otherwise of chlorina type. In some 

 cases these spots vary in number and size from leaf to leaf; in 

 others they are hereditarily fixed. Some of the variegated races, 

 on account of the smallness of the green spots, are difficult to 

 distinguish from the chlorina types. On some of the variegated 

 plants, especially those having much green, typical green 

 branches occur, and this phenomenon is characteristic of the 

 plants on which it occurs. That is, the same plant year after 

 year produces these green branches. Every possible gradation 



1 Investigations on Inheritance of Yellowish Green and Variegated Kaces 

 of MirabUis Jala,, a. Vrtira pihilifera and Lunaria amma. Z> itarh. f. Abst- 

 u. Yererb., 1, 1909, H. 4. 



