TWINNING IN DASYPUS NOVEMCINCTUS 59 



The upper fetus on the left is fetus I, its i)artner is 

 II; the lower right fetus is III and its partner is IV. 



Fig. 19. — An armadillo egg about six weeks after fertilization, 

 showing the two pairs of fetuses, revealed by the removal of part of the 

 egg membranes. Each has its own oval placental area, its own amnion, 

 umbilicus, etc. The heavy dotted lines indicate the boundaries of 

 the removed portion of the placental disks of the two nearest embryos. 

 (See stage XL) 



Each fetus has its own amnion, but at this time the 

 amnia occupy only a small part of the total volume 



