riiOFESSOlt K. PEARSON AND OTHERS ON 
:V2(; 
Woodruff. 
Number of 
Mean. 
S. D. 
Coefficient 
of 
variation. 
S.D. 
of array. 
Percent- 
age 
variation. 
Correla¬ 
tion. 
: 
1 
Spraj^s. 
Whorls. 
Pairs. 
Pairs ... 
IMiorls 
1 201 
146.5 
1.32301 
6-7978 + 
•0164 
6-9010 
•9318 + 
•0116 
•9291 
13-4631 
•9177 
98-49 
•1733 [ + 
•0171] 
The frequency distribution of the 1465 whorls was :— 
Number of 
4. 
5. 
6. 
( . 
8. 
9. 
10. 
Total. 
; 
Frequency . . . 
6 
40 
537 
410 
455 
16 
1 
1465 
The doidde inodes G and 8 are brought out by the above distribution, and this is 
evidence either of differentiation or of a tendency to an even number of members. 
Contrary to the nsual rule, tlie mean number of members is reduced when we take 
pairs, indicating that when v’e take a spray vdth many whorls—such as occasionally 
arises from forking—the nnmlier of members in the whorls are reduced, and since 
the variation is also very slightly increased (as in Nigella), they are spread out over 
a o-reater rano'e. 
The great reduction in the correlation, the value of which is only '1733, shows how 
unsuited the material was for the purposes of the present investigation. At the same 
time the lutio of the individual to the racial variability reaches the very high value 
of 98'5 ! We have .selected a character to test individuality on, which exhibits 
differences which are largely racial, and not peculiar to the individual plant. 
Sectiox IV.— Ferns. 
(16.) In choosing ferns for considering the resemblance between undifferentiated 
like organs I had in view not only the comparative ease of counting (as compared, 
for example, rvith the segmentation of mallow), but the fact which students of the 
fern strongly impressed iqjon me that it was peculiarly subject to its environment. 
One great authority went so far as to assert that the presence or absence of sort on 
an individual hartstongue depended solely on the environment and not at all on the 
individuality ot the plant. While hardly prepared to accept to the full such a 
statement (for I had already learned in a variety of types of the existence of 
ijuhviduahty in a marked manner a])art from the influence of environment), I 
