146 
EOTAL HOETICULTUEAL SOCIEXr. 
that uniformity of external conditions presents no bar to varia- 
tion. It must be remembered that in speaking of variations I 
am not here alluding to mere varying degrees of vigour. In 
box 4}, however, all the plants were more " stocky " than in the 
other boxes ; i. e. the rhizome was more freely divided into thick 
branches than was the case in the otber boxes. In box 3 the 
root-fibres were more copious than in the others. 
Achillea Millefolium. 
Boxes 
1. 
2. 
3. 
4. 
5. 
6. 
1870. 
April 25 
a 
h 
e 
c 
/ 
d 
May 2 
a 
c 
e 
h 
/ 
d 
» lb 
a 
c 
a 
7 
0 
f 
e 
„ 23 
a 
c 
d 
h 
» 30 
a 
d 
"f 
e 
June 6 
a 
h 
d 
c 
e 
f 
„ 13 
a 
c 
e 
b 
d 
f 
„ 20 
a 
c 
d 
b 
e 
f 
„ 27 
a 
h 
c 
f 
July 4 
a 
h 
c 
f 
11 
a 
b 
c 
d 
„ 18 
e 
d 
"f 
c 
Cut on July 21. 
1871. 
April 22 
a 
h 
c 
d 
„ „ Eoot... 
a 
h 
c 
d 
e 
f 
The unmanured plants were the least vigorous of any. 
Those treated with mineral manures and with nitrate of soda 
respectively were of a relatively low degree of development. 
The ammonia salts produced a somewhat better growth, while 
tbe mixed manures 5 and 6 produced, on the wbole, the best 
plant, though subject in each case to considerable variation. 
The roots were least developed in the unmanured box, and 
most so in box 6. All the plants were healthy till injured by 
drought, which caused the flowers to fall off before the seed 
