404 
Note on Dr Simpsons Memoir 
wards. I found the application of solutions of gelatine to be as effective and 
less deleterious than any other agent. But it is obvious that the differences in 
environment — from a normal medium to one to which such gelatine has been 
added — when repeated more than once especially within a short period for pur- 
poses of measurement must have soaie influence upon later growth even when the 
greatest care is taken, and it is highly probable that this influence is seen in the 
difference in index correlation to which Professor Pearson calls attention in his 
note below. 
Note on Dr Simpson's Memoir on Paramoeciuvi caudatum. 
(1) Dr Simpson's results are clearly not purely homotypic as far as the correlations 
between pairs of members are concerned, but largely affected by the growth factor, the 
measurements of pairs having been made at all sorts of intervals after division. They cannot 
therefore be used in their present condition as a means of appreciating homotyposis in the 
results of linear division. In order to reach pure homotyposis we must obtain measurements 
of growth in length and breadth diu-ing a variety of periods after division. The labour, 
however, of obtaining measurements on pairs of members at a definite interval after division 
being very great, Dr Simpson was only able to provide the set of measurements in the 
accompanying Table IV. These involve eleven pairs measured twice and three of them measured 
thrice. It will be seen at once that the growth is very irregular, and even more so in breadth 
TABLE IV. 
Divided 
Measured 
Length 
Breadth 
Measured 
Length 
Breadth 
Measured 
Length 
Breadth 
1st pair 
May 22, 11 a.m. 
5 p.m. 
210 
70 
May 23, noon 
225 
75 
May 24, 11.30 a.m. 
225 
80 
230 
55 
245 
65 
245 
70 
2nd pair 
May 22, 11 a.m. 
4.30 p.m. 
230 
80 
May 23, 1 p.m. 
240 
90 
245 
70 
260 
90 
3rd pair 
May 22, 10 a.m. 
4 ixm. 
225 
60 
May 23, 1.30p.m. 
230 
75 
220 
60 
225 
70 
4th pair 
May 22, 5 a.m. 
10 a.m. 
210 
75 
May 23, 12. 30 p.m. 
220 
75 
May 24, noon 
225 
75 
220 
75 
230 
75 
235 
80 
5th pair 
May 22, noon 
5.30 p.m. 
240 
85 
May 23, 1.15 p.m. 
245 
85 
May 24, 1.30 p.m. 
245 
85 
230 
80 
235 
80 
235 
80 
6th pair 
May 22, 6 a.m. 
3 jj.m. 
220 
65 
May 23, 4 p.m. 
230 
70 
215 
70 
220 
75 
7 th pair 
May 23, 5.30 p.m. 
6.30 p.m. 
175 
65 
May 24, 1 p.m. 
230 
85 
180 
60 
240 
80 
8th pair 
May 23, 4.30 a.m. 
6 p.m. 
195 
60 
May 24, 1.30 p.m. 
230 
80 
220 
70 
245 
90 
9th pair 
May 23, 4 a.m. 
6.15 p.m. 
230 
60 
May 24, 12.30p.m. 
250 
70 
215 
75 
240 
90 
10th p&ir 
May 23, 4 a.m. 
6.45 p.m. 
225 
70 
May 24, noon 
260 
95 
235 
65 
270 
85 
11th pair 
May 23, 1 p.m. 
5.45 p.m. 
205 
60 
May 24, 2 p.m. 
220 
75 
230 
70 
235 
90 
