364 
Journal o f Agricultural Research 
Vol.’XXIX, No. 8 
several thousand single-comb White 
Leghorn chicks at the Indiana Ex¬ 
periment Station. The sexes were 
weighed together until the young 
cockerels could be picked out, and from 
this time on to the end of the twenty- 
fourth week only the pullets were 
weighed. Card and Kirkpatrick (2) 
published their growth studies which 
had been carried on during the three 
preceding seasons. They used single¬ 
comb White Leghorns and Rhode 
Island Reds from the regular stock 
of the Connecticut Experiment Sta¬ 
tion at Storrs, Conn. The chicks 
were carefully weighed in lots, once 
per week, and the average weight per 
chick determined for 24 weeks. The 
cockerels were removed at the end of 
the eighth week and after this only 
the pullets were weighed. Buckner, 
Wilkins, and Kastle (1) studied the 
growth in body weight of two lots of 
single-comb White Leghorn chickens 
at the Kentucky Experiment Station. 
One group was incubator-hatched and 
raised in a brooder; the other was 
hatched and reared by hens. They 
started with 60 chicks in each lot. The 
chickens were weighed individually each 
week and the average for each sex was 
determined for a period of 28 weeks. 
When we turn to the growth of the 
systems or organs of the domestic 
fowl, we find still less in the literature. 
Welcker and Brandt (28) give the 
body weight and the, weights of the 
organs and systems in two male 
domestic fowls. There are also some 
weights given for the organs of the 
chick on the 9th, 10th, 11th, 13th, 
17th, 20th and 21st days of incubation, 
one “Junges Hiihnchen vom Markte” 
and a hen. The breeds are not given 
and, of course, the number of cases 
is not adequate to determine the 
average weights. They give similar 
data for nine other species of birds, 
including two pigeons and two do¬ 
mestic geese. Zaitschek (81) autop- 
sied “131 Stuck voll entwickelten 
Huhnern ungarischer Rasse und ver- 
schiedenen Alters.” He finds that 
the blood (that which escaped from 
the chicken) forms an average of 3.8 
per cent (range 2.6 to 5.6 per cent); 
the feathers average 7.7 per cent 
(range from 1.4 to 11.4 per cent); 
and the liver forms an average of 2.9 
per cent (range from 1.4 to 4.7 per cent) 
of the live weight. These were the 
only organs weighed separately. 
Stieve (25) studied the development of 
the ovary in the hen, but made no 
observations upon the other organs. 
MATERIAL AND METHODS 
The chickens used were single-comb 
White Leghorns, which were provided 
by the Division of Poultry Husbandry. 
They were hatched in four groups. 
Group 1 was hatched May 29, 1920, 
but the weighings were not begun 
until June 26, at which time there were 
95 chicks four weeks old. On July 13 
this lot was transferred to two coops 
with free range, and 32 culls were 
removed. On October 27, 1920, they 
were moved into winter quarters and 
the sexes were separated. Group 2 
was hatched July 8, 1920, and included 
21 chicks. Group 3, hatched July 17, 
1920, consisted of 36 chicks. Groups 
2 and 3 were kept in the brooder house, 
but during the latter part of the sum¬ 
mer and fall they were allowed to run 
in a large, grassy, fenced lot adjacent 
to the small runs. The last chick in 
Group 2 was autopsied November 13, 
1920. Groups 1 and 3 were in part 
carried through to the end of the 
experiment, and the remaining chickens 
returned to the Poultry Department. 
The males and females in Group 3 were 
not separated. Group 4 included 18 
chicks, hatched August 11, 1920. 
The last one of this group was autopsied 
November 15 : 1920. 
All of the chicks were hatched in 
the incubators at the poultry plant' 
and, with the exception of Group 4, 
they were all put into the brooder 
house as soon as all chicks in the 
incubator were dry. This was usually 
about 24 hours after the first chick 
had hatched. The age of the chickens 
was counted from the time of removal 
from the incubator, so there is a 
variation of a maximum of about 24 
hours in their ages. Group 4 was 
given to an old hen confined in a coop. 
This allowed free range for the chicks. 
Later the hemand chicks were put in a 
section of the brooder house with access 
to a grassy run. 
From the beginning, all were fed 
a commercially prepared mixture of 
seeds, and a commercially prepared 
mash. After June 21, 1920, ail the 
chicks were provided with hoppers 
filled with a mash composed of equal 
parts, by weight, of bran, hominy, 
middlings, ground oats, and beef scraps. 
As soon as old enough, they were given 
a mixture of cracked grains, corn, oats, 
etc., and later whole grain. The last 
three groups were given milk to drink 
from the beginning, and Group 1 was 
also given milk after June 26. After 
November 27, 1920, the remaining 
