Figure 34. Illustration from Baer, "On Double Monsters." 



A — double-headed perch embryo; a — outer or upper plate of 

 the rudiment corresponding to the abdominal wall of the 

 embryo j b — Internal or ventral plate of the rudiment or 

 allantoic sac. B — double-bodied embryo of a chicken in the 

 embryonic sphere, at the beginning of the third day; 

 ABCD — transparent embryonic sphere; E — the common head; 

 F — approximate outlines of the heart; a — thickened place 

 on the head between the skull and thickened edge of the 

 abdominal plate . C — adult cow with additional growth in 

 the left side of the neck. D — newborn baby with additional 

 legs in the pubic region. 



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