(S Iiullctinv N0. 220 `
in every way, each having access to a   plot of about 011e- n
fourth of an acre. l*`rom this point on, all of these lots of chicks
received identical treatment, with the exception of their food.
ln each of the grass plots shade was provided and, as far as pos-
sible, the conditions governing these chicks were ideal. _
During the 28 weeks of this part of tl1e experime11t 110
unusual weathe1· conditions occurred except excessive heat dur-
ing the llth week, which seemed to cause a loss of appetite, aud, K:
since the chicks were entirely tree from any disease, we ca11 J
say that any variation in the general condition and weight of
any of the lots except N0. 4 might be attributed directly to tl1e
rations ted to them.
At the beginning of the experiment all the chicks of these
eight lots were weighed individually on a torsion balance sensi-
K tive to t).l gram and they were so weighed at the end ot each
week during the 28 weeks over which the tirst ]}2ll'l ot' the ex-
periment extended. Also, a mortality record was kept and when
a chick died l`rom any cause, its weight record was discarded,
so that, at the end ot' 28 weeks, we compiled our results from the
records ot the chicks remaining at that time. 'l`his was done
in order to avoid any error in the average weight of the chicks
caused by a possible loss in weight previous to death.
\Vhen treading began, the cockerels and pullets were sep-
arated in all lots except liot 2. in order to avoid any loss in
weight on the part of tl1e pullets, caused by undue exercise. ln
the case of Lot 2. the external sexual characteristics were rudi-
mentary and at the end of 28 weeks we were unable to dis-
tinguish the cockerels t`rom the pullets. lt is also ot interest to
know that there was no attempt made at treading in this lot V
and it rarely occurred in liot ll. 7
'l`his part of the experiment began on April l8 and was
.discontinued tlctober Stl.
The rations. as t`ed to the separate lots. are as follows: