OBSERVATIONS ON THE HABITS OF ECHIDNA. 323 
One or two eggs are laid about twenty-seven days after copula- 
tion. When the egg is laid the degree of development of the 
embryo corresponds roughly to that of a third-day chick or a ten- 
days’ rabbit. The amnion is not closed, and the allantois has 
apparently not begun to form. It is probably a couple of weeks 
later before the egg is hatched. During the period of incubation 
the egg is carried about by the mother, placed in the bottom of 
the temporary pouch, and secured by the abdominal hairs 
plastered across it. After hatching, the young is apparently 
carried about till it is a good size, and able to look after itself. 
