116 ARTIFICIAL PARTHENOGENESIS AND FERTILIZATION 
The values are practically identical. The eggs treated 
with the hypertonic solution developed after being put in normal 
sea-water. 
In a second experiment the unfertilized eggs consumed after 
membrane formation with butyric acid in normal sea-water 
0.52 mg. O, in 65 minutes. The same eggs were then put into 
hypertonic sea-water (50 ¢.c. sea-water+8 c.c. 23 m Ringer) 
and consumed here in 65 minutes 0.54 mg. O.. The tempera- 
ture was in both cases 18°. These eggs developed after being 
transferred to sea-water. 
In another experiment the unfertilized eggs consumed, after 
the artificial membrane formation with butyric acid, 0.83 mg. 
in 60 minutes in normal sea-water; during the next hour they 
were put into hypertonic sea-water and consumed in 60 minutes 
0.74 mg. During the next 60 minutes they were again put into 
normal sea-water where they consumed 0.70 mg. O, in 60 
minutes (at the same temperature).! 
It is obvious from these experiments that the hypertonic 
solution does not act by increasing the rate of oxidations. This 
agrees with the conclusion we reached before, that the mem- 
brane formation is the real activating agent while the hypertonic 
solution acts only as a corrective. 
3. Warburg’ states that if the eggs of S. lividus are fertilized 
with sperm and afterward put into a hypertonic solution the 
rate of oxidations is thereby increased 300 per cent. Since 
Wasteneys and the writer found that the hypertonic solution 
of the concentration required for artificial parthenogenesis does 
not raise the oxidations of the eggs of S. purpuratus after 
artificial membrane formation, we were curious to know whether 
such a hypertonic solution raises the rate of oxidations in the 
eggs of S. purpuratus fertilized with sperm. Table XII gives 
the result. — 
1 Loeb and Wasteneys, Jour. Biol. Chem., XIV, 469, 1913. 
2 Warburg, Zeitschr. f. physiol. Chem., LX, 443, 1909. 
3’ Loeb and Wasteneys, op. cit. 
