PROFESSOR K. PEARSOX AXD OTHERS ON 
S16 
So that the variability of both may be expressed in round numbers as 16. It is 
clearly not a constant for the whole vegetable kingdom, but 16 enables us to 
form some rough appreciation of the jolasticity of vegetable forms, and may be 
compared with values obtained from other series later. 
Comparing again the ratio of the racial and individual variabilities, we see that 
the latter reaches, on an average, over 85 per cent, of the former, the minimum value 
being 79 and the maximum 91. It is difficult to test this point directly, for the 
very simple reason that a single plant will, as a rule, have very few flowers; and upon 
small numbers it is impossible to test satisfactorily the full variability of the plant. The 
probable error becomes enormous if we have only four or five capsules to determine 
the standard deviation from. The method adopted has been that which arises in 
the treatment of parental inheritance ; all the offspring of parents of a given 
stature are clubbed together and form an array. This array has a certain varia¬ 
bility, and this variability is taken to be that of a single family of ofispring hawng 
parents of tiie given stature. It would clearly be impossible to find the variability 
inside the familv from nundjers such as occur in a sinole human familv. To some 
O «/ 
extent we can verify the assumptions thus made. Thus I took the wild poppy with 
the largest number of capsules I had come across, and determined their variability; 
there were 36 such capsules, and the standard deviation was 1'4519. I then took 
two of the most prolific Shirley poppies which had 126 and 85 capsules on them, 
and their variabilities were given by standard deviations of 1‘3290 and 1'5889, be., 
a mean of 1'4589. These are actually in excess of the standard deviations of the 
arrays, namely, 1'3661 and 1'4019 of the two series of poppies! I think we may 
accordingly take the latter as a reasonable measure of the possible variation of the 
individual. 
Table IX. — Wild Poppy (Chilterns’ Top) Series (i.). 
Xumber of Siigviatic Bands on First Capside. 
5. 
6. 
7. 
8. 9. 
10. 
11. 
12. 
13. 
14. 
15. 
! Totals. 
5 
0 
8 
4 
1 
12 ; 
6 
8 
38 
46 
23 
11 
5 
2 
— 
__ 
— 
— 
133 ' 
7 
4 
46 
184 
163 
146 
78 
31 
8 
1 
— 
661 1 
8 
— 
23 
163 
390 
398 
279 
111 
75 
32 
4 
— 
1475 
9 
— 
11 
146 
398 
554 
415 
250 
161 
68 
9 
5 
2017 
10 
— 
5 
78 
279 
415 
514 
520 
240 
112 
27 
10 
2200 
11 
— 
0 
31 
111 
250 
520 
770 
366 
160 
52 
9 
2271 
12 
— 
— 
8 
75 
161 
240 
366 
252 
178 
35 
12 
1327 
13 
— 
— 
1 
32 
68 
112 
160 
178 
92 
23 
11 
677 ! 
14 
— 
— 
— 
4 
9 
27 
52 
35 
23 
28 
12 
190 1 
15 
— 
— 
— 
— 
5 
10 
9 
12 
11 
12 
4 
63 1 
ToUils 
12 
133 
661 
1475 
2017 
2200 
2271 
1327 
677 
190 
63 
11026 
1 
