No. 520] NOTES AND LITERATURE 



247 



sex-phenomena. The fact that in the gametes, particularly the 

 otrirs, besides certain phosphorus-containing proteins, lecithin is 

 abundantly present, suggested a series of experiments to deter- 

 mine whether the lecithin content of *\tr«rs could be artificially 

 increased and whether such accession could produce a significant 

 physiologic modification in the germ-cells. 



Russo finds that normally in rabbits and various other mam- 

 mals the lecithin content of eggs of the same ovary varies 

 greatly; some containing much, others little. This variable cell 

 condition indicates a shifting chemical state, expresed morpho- 

 logically in the form of "chromidial-bodies" (mitochondria, 

 chondriomites, pseudochromosomes, chromidial net, etc.). These 

 structures Russo has succeeded in producing by artificial means 

 (i. e., injection of lecithin), and he regards them as having "no 

 small influence on developmental phenomena." He does not 

 deny that the nuclear chromatin plays an important role in 

 development, but he refuses to regard it as alone the material 

 basis of heredity. The nuclei may assist in the process of hered- 

 ity, but the results of his investigations on rabbits indicate that 

 sex and other "unit characters" (e. g., pigmentation) are a func- 

 tion of the degree of cell metabolism. 



Russo believes that "contrary to the chromosome theory, the 

 characters of Mendelian hybrids in the first or dominant genera- 

 tion, especially as concerns the pigmentation and color of the 

 hybrid, do not bear any absolute relation to the chromosomes, 

 but that they depend in greatest part upon a specific metabo- 

 lism or chemical condition residing in the egg cytoplasm; that, 

 further, the sex of the offspring depends upon a special metabo- 

 lism (Stoffwechsel) of the germ-cells, and that by artificial 

 modification of the chemical or metabolic state (Metabolismus ) 

 of these elements the Mendelian law (i. e., of dominance) can be 

 modified in that one may fix this or that most recent variety, 

 as it is also possible at will to determine the sex" (p. 4). 



Lecithin was administered subcutaneously. int raperitoneally 

 and per os. The ovaries of lecithin-fed rabbits attained a size 

 three times as great as that of ordinary individuals and con- 

 tained much larger Graafian follicles. Under such treatment 

 the germ cells became markedly anabolic. Russo notes that in 

 normal ovaries some ova contain much deutoplasmic material 

 in the zona pellucida and the vitellus, and others little or none. 

 The artificially highly nourished eggs produce females; and the 

 lecithin-fed individuals give rise preponderatingly or even ex- 



