6 4 



JACQUES LOEB. 



hybridization. The embryo in Fig. 12 consisted practically only 

 in a pulsating heart, what was left of the embryo was much less 

 conspicuous than it is in the drawing. The embryo was ten days 

 old. The egg had been put into the temperature of between o 

 and 2 when it was in the 2-cell stage and had remained there 

 for twenty-four hours. 



The remnants of the embryo Fig. 13 had the same history. In 



QGCASSIONAIJ 

 CONTRACTION 

 OF TAIL 



REGION OF 

 BEATING HEART 



FIG. 13. 



this case, curiously enough, one eye with a lens and the tail was 

 all that could be recognized. The monstrosity when drawn was 

 eleven days old. An inexperienced observer might easily have 

 concluded that in this case only the eye had been developed, 

 while in reality the whole embryo had developed but the eye 

 had survived while other parts perished. 

 The analogy with teratomata is obvious. 



