236 



The Mechanism of Evolution" in Leptinotaesa 



the characteristics, as do similar conditions produce like ranges in characters 

 of non-organized matter ; and (c) it is possible that the range is due to many 

 small actual differences in the constitution — "germinal variations" — ^which 

 the methods used or the criteria of the index used are not able to separate out 

 into the component groups. 



Tabui 29. 



No. of mating. 



Parents, 

 index. 



M. 



Progeny. 



Fraternity No. 



Range of index. 



Totals. 



l.gl 



2.gl 



S.gl 



4. g II 



5.gl 



6.gl 



7.gl 



S.gl 



9. gl 



10.gl 



U.gl 



12.gl 



13.gl 



14. gl 



16. gl 



16. gl 



17.gl 



M.2.gl 



M. 2. g 1(A) . 

 M. 2. g KB). 

 M. 2. gl(0 .. 



2.761 

 2.749 

 2.660 

 2.739 

 2.570 

 2.790 

 2.738 

 2.629 

 2.619 

 2.700 

 2.762 

 2.689 

 2.766 

 2.969 

 2.680 

 2.900 



2.600 



f2.951 



2.600 



L2.754 



2.630 

 2.694 

 2.786 



2.699 



2.931 



2.761 



2.760 



2.771 



2.870 



2.731 



2.700 



2.901 



2.791 



2.898 



2.894 



2.715 



2.769 



2.763 



2.715 



2.825 

 2 



2.911 

 2.716 

 2.826 



1. gll .... 



2. gn .... 



5. gn .... 



4. gn .... 



6. gn .... 



6. gll .... 



7.gn .... 



8. gn .... 



9.gn .... 



10. gn .... 



11. gu .... 



12. gn .... 



13. gn .... 

 14. gn .... 

 15. gn .... 



16. gn 



17. gn 



M. 2. gn ... 



M. 2. g 11(A) 



M. 2. gn(B) 

 M. 2. g n(0) 



{f: 



fM. 

 IF. 



(M. 



(P. 



1^: 



fM. 

 IF. 

 fM. 

 IF. 



{f. 

 fM. 

 IF. 

 (M. 

 IF. 

 fML 

 IF. 



{f"; 



fM. 

 [F. 

 fM. 

 (F. 

 fM. 



If. 



JM. 



If. 

 {f 

 if. 



fM. 

 IP. 



{^; 



6 



4 



11 



10 



8 



14 



17 



2 



11 



5 



4 



7 



1 



4 



7 



3 



6 



16 



8 



1 



6 



6 



5 



4 



1 



1 



17 



14 



15 



6 



3 



4 



6 



3 



46 



77 



1 

 12 

 6 

 6 

 3 

 1 



fl} "« 



%} 1« 



fe} ^^^ 

 ^} «= 

 11} "^ 



11} 



ill} «i= 



21) 

 31 J 



in "B 



fe} ^ 

 Vz} "^ 



^} '« 



Total 4113 



The first attack was made to determine whether the "environment" was 

 either primarily or even partly responsible for the condition found in the range 

 exhibited in the index. For this, therefore, I set up 13 breeding-tanks of the 

 construction and arrangement of control shown in figure 33 (Chap. I), and 

 arranged to give constant conditions of temperature and moisture, air-move- 



