A quantitative Study of Variation, Natural and Induced, etc. 189 
balance. It is possible too that a test of the plants in a second 
generation may show residual effects from the injection treatments. 
In order to show that the injections did affect the plants to a 
great degree even though not sufficiently to produce mutations, the 
statistical method was adopted. The data obtained are shown in 
the tables of constants under ‘‘Materials and Methods’. Since, as 
will be shown in chapter II, the plants in the whole experimental 
plat varied by lines, each line from an injected capsule is compared 
with a correspondling line from a capsule not injected. Which is to 
say that any comparison to be of value must concern the same 
mother- (second generation) plant. To group all plants from injected 
capsules together and compare them with all plants from capsules 
not injected would be of little value. 
Let us compare then the treated and untreated capsuleprogeny 
of each of the mother plants. 
Plant No. 250—1. 
Height 
Pedigree Chem. St. Dev. Coef. of Var. 
250—I c 596 Ca(NO,); 4.210 + 224 6.33 + 337 
» C581 ZnSO4 4-954 324 7-77 & 509 
resol H,O 5.9I2 + 279 8.98 + 424 
» 165098 Ca(NOs3)o 4.125 + 227 6.05 + 333 
1a — 5.501 + 185 8.58 + 289 
Width 
» 1596 Ca(NO;), 3-437 + 183 959+ 511 
is 1c 581 ZnSO, 3-851 + 252 11.44 + 759 
Ic sol H,O 3-161 + 149 8.87 + 419 
» 1598 Ca(NO3)o 3-123 + 172 8.20 + 452 
1a —_ 3-698 + 125 10.87 + 367 
Number of Branches 
” Ic 596 Ca(NO,); 2.122+ 113 10.53 + 567 
ny) TICHHEL ZnSO, 2.386 + 156 13.08 + 871 
= Ic 591 H,O 2.041 + 096 9.80+ 463 
Pe LeCusgS Ca(NOs)o 2.120 + 116 10.61 + 590 
» 1a — 1.653 + 05 8.56 + 289 
Number of Seed Pods 
A 1 C 595 Ca(NO,), 43.278 + 2.308 18.10 + 996 
é Ic 581 ZnSO, 47-547 + 3.115 18.04 4 1.219 
; Ic 59! H,O 52.693 + 2.488 19.244 941 
5 1c 598 Ca(NO;); 50.460 + 2.779 18.52 + 1.054 
» 1a = 47-243 + 1.593 20.35 + 713 
