80 



CARNEGIE INSTITUTION OF WASHINGTON. 



One of the two derivatives noted above had an F2 or second genera- 

 tion which was exactly identical with the Fi or first generation. The 

 other derivative presented a marked disturbance of correlations in the 

 Fi by which the leaves and flowers were irregular in many features, 

 such as shape, rate of growth, color-patterns, etc., in the first generation, 

 w^hich in the second generation gave way to balanced differences from 

 the parental type, and resulted in individuals not exactly identical 

 with the single parent of the first generation. Both types of departure 

 included a change in color-pat- 

 terns in flowers, in structure of 

 leaves and stems, and in develop- 

 mental velocities. 



(3) Colored solutions intro- 

 duced into the ovaries of Scrophu- 

 lariaweve taken up by the funicu- 

 lar stalks, carried to the nucellus 

 and antipodal regions, and then 

 difTused to the egg-apparatus. It 

 seems probable, therefore, that 

 the reagents producing the de- 

 partures noted above did so by 

 their action on the egg-nucleus 

 or upon the fertilized egg. The 

 difTerences between the two de- 

 rivatives may rest upon the two 

 possibilities noted. (Fig. 3.) 



(4) The colloidal complex of 

 living matter includes a great 

 number of closely relatedunstable 

 compounds giving a wide variety 

 of reactions or transformations. 

 Some of these may be checked or 

 stopped, others facilitated, or 

 new reactions set up by intru- 

 sive substances. The compound, 

 potassium iodide, used does not unite with, proteins, but exerts a neu- 

 tralizing or coagulatory action on them. Some departures might be 

 evaluated as losses of characters ; others, such as new incisions in corolla 

 limbs and new lateral veins in leaves, are increased differentiations. 



(5) The changes produced are not premutational or cumulative, but 

 are induced by direct physico-chemical action, and may be considered 

 profitably without recourse to the conceptions of a complicated genetic 

 terminology. 



(6) A necessary preparation for the accurate use of this method 

 consists in ascertaining the course of diffusion of the reagent, the time 



Fig. 4. — Longitudinal section of the basal portion 

 of the flower oi Scroplndaria, to illustrate me- 

 chanical features of importance in ovarial 

 treatments. The stippling shows the accu- 

 mulations of methylene blue in the placenta 

 and ovules, c, corolla; s., sepals; g., nectar 

 gland; p., placenta; st., style; ov., ovule; rec, 

 receptacle; n., tip of needle thrust through 

 the ovarial wall and penetrating the placenta. 

 (Drawn by F. E. Lloyd.) 



