ARTIFICIAL PRopUCTION OF NoRMAL Larve 611 
of the irregular morula stage is preserved. This is intel- 
ligible if we remember that the blastula originates through 
the cleavage cells moving or sticking to the periphery of the 
egg. The other blastule represented only smaller pieces of 
asingle egg. In some cases one part of the egg disintegrated 
and formed débris at- . i. 
tached to the other part ~ 
which reached the blas- 
tula stage (5, 6, and 7). 
Each one of these blas- 
tule was moving and 
had to be immobilized 
tomakethe cameradraw- 
ing. It is impossible to 
give a fair idea of the 
variety of forms of blas- 
tule one sees in such ex- 
periments. No egg of 
this lot (solution 1) 
reached the pluteus 
stage. All died the 
second day. The eggs 
that had been in solu- 
tion 2 (equal parts of FIG. 150 
22n MgCl, and sea-water) looked very different from the 
preceding lot (Fig. 150). After twenty-four hours many 
of them had developed into blastule. These blastule left 
no doubt that they came from eggs without a membrane, in- 
asmuch as in the majority of cases several blastule originated 
from one egg. Quadruplets were especially frequent (Fig 
150, Iv and v), but twins and triplets were also quite com- 
mon. I watched their development, and am thus quite cer- 
tain that these multiple embryos sticking together came from 
one egg. The feature that distinguished these embryos 
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