6 4 



Scientific Proceedings (97). 



Line Ohr after occurrence of endomixis in the 896TH generation in its 



BREAKING UP PROCESS; ONLY MEAN LENGTHS IN THREE SUBSEQUENT 

 ENDOMICTIC PERIODS ARE GIVEN IN UNITS. 



(One unit = 3.5 microns. 



Ohr 808 

 41.983 ± -293 



Ohr 896,0 

 39.625± .152 



Ohr 846 

 4i-700± .477 

 Ohr 896,6 Ohr 896,* 



39-941 ±-277 37. 708 ±.180 



Ohr 896^ 

 37-598 ± .380 



Ohr 896 vt 

 42.695 ± .176 



Ohr 932 „ 

 39-755± -234 



Ohr 978,0 

 39.866 ± .255 



not further 

 selected 



died 



died 



Ohr 93 5 v, 

 42.450 ± .12 



Ohr 98 1 re 9 



42.56o± .130 



period and the selection for a certain mean length repeated, it is 

 possible to isolate lines with different characters. The table 

 shows the measurements for two cultures, carried through three 

 subsequent endomict ; c periods, derived both at the 896th genera- 

 tion, these lines Ohr 896,,,, and Ohr 896„ e remain "constant." 

 The same phenomenon was unintentionally attained when during 

 our joint studies, Dr. Woodruff and I kept for a long sequence of 

 generations Line IE isolated from Line I, the famous Line already 

 under laboratory observation since 1 907. The breaking up in 

 "hereditarily diverse stocks" in this line could not be attributed 

 to the supposed effects of the culture methods that varied only 

 for about 800 in the total 2,200 observed generations, for both 

 lines. I cultivated Line O, either in hay infusion or bouillon, 

 either in room temperature or in constant temperature. The 

 dimensions in the beginning show a more or less marked decrease, 

 but later come nearly to the old standard. Such a considerable 

 difference as Lines I and IE or Lines Ohr 978^0 and Ohr 981,,, 

 show and maintain, can not be affected by environmental changes. 



