180 ARTIFICIAL PARTHENOGENESIS AND FERTILIZATION 
this is actually the case. Thus unfertilized eggs were distributed 
among the following solutions: 
(1) 25 ¢.c. m/2 NaCl+0.1 ¢.c. m/10 sodium oleate 
(2) 25¢.c. m/2 NaCl+0.1c.c. m/10 sodium oleate+0.2 c.c. N/10 
NaOH 
(3) 25 c.c. m/2 NaCl+0.2 c.c. N/10 NaOH. 
In the first solution, the eggs became angular, but hardly 
one formed a membrane; in the second solution, 50 per cent of 
the eggs formed very delicate membranes that soon tore, and 
many of the eggs cytolyzed; in the third case the eggs remained 
quite intact. 
But cytolysis of the eggs in the soap solution can also be 
obtained by raising the concentration of the soap solution high 
enough. Thus, if the eggs are put into 50 c.c. m/2 NaCi+1 cee. 
m/10 sodium oleate, membrane formation and cytolysis begin 
practically at once. I suppose such a solution has a faintly 
alkaline reaction. If excess of HCl is added to this mixture, 
membrane formation is not prevented; in this case free oleic 
acid is formed, and this, as I observed in 1905, also initiates 
membrane formation and cytolysis in the egg. 
We have already seen that an alkaline solution of NaCl 
without soap has only a relatively weak cytolytic effect. The 
addition of 0.2 c.c. of m/i0 sodium oleate+0.4 c.c. N/10 
NaOH to 50 ¢.c. of NaCl has just as much effect as the addi- 
tion of 2 ¢.ec. NaOH without soap. 
Now it is easy to convince oneself of the effect of soap in 
causing development. It is only necessary to transfer the eggs 
after a short time from the soap solution to ordinary sea-water, 
and subsequently (after repeated washing) expose them to 
hypertonic sea-water. The following example will illustrate 
this: Unfertilized eggs were placed in 50c.c. m/2 NaCl+ 
0.2 ¢.c. of sodium oleate and after two or three minutes trans- 
ferred to sea-water. The majority of the eggs formed mem- 
branes and only a few cytolyzed. The eggs were washed 
