682 HENRY H. DONALDSON 
1. The changes in the percentage of water 
As to the percentage of water in the entire frog, I made the 
determination in the Chicago frogs by drying the animals for sev- 
eral weeks in the same oven which was used for the determina- 
tion of the percentage of water in the brain and spinal cord. 
From each series in the Chicago lot, with the exception of 1, 
2, 35 and 38, one male and one female frog were taken; both 
were weighed fresh and then opened and the ova removed from 
the female when necessary. Care was taken of course that no 
other tissue was lost by the operation. 
The results are given in table 10, first for single series, then for 
the averages of the several series grouped in the way in which the 
series appear in table 3. The entries for the series, 13, 14, 15 
and 16, which series were not used for the determination of C, 
are also given, and it is interesting to note that there was nothing 
peculiar in the amount of water in the entire frog in these cases. 
TABLE 10 
On the amount of water in the entire frog. Chicago frogs, by single series and by 
groups 
PERCENTAGE OF WATER 
SERIES © DATE MALES | agar FEMALES 
ees i ee 
SERIES GROUP | SERIES GROUP | 
ot evar ee Aas ams. 
1 nae March 29 | | | | | 
Ze ae: April 4 | 
Sere April 10 | 
AeA Ae April i fame ess ri Team 2126 81.4 81.4 | 16.6 
Ce ae April 24 | 80.1 | 81.0 |] 
(oes May 1 erie Pari 80.8 | 
80.5 | 22.9 80:7 |. 21-3 
Teste May 8 80.1 80.8 | 
Bate ees May 15 82.1 79.3 
YBa! May 22 Sr aren | 81.4 |) 
10) eee May 29 8 leo a | aare 82.2 Si 9 aoe 
eee June 5 80 3 | Wee 81.8 
He June 12 ise | 79.4 | 
