THE FETAL MEMBRANES AND EARLY HUMAN EMBRYOS 



The following are the estimated ages and lengths of human embryos, accord- 

 ing to Mall, and their weights, according to Fehhng: 



Crown-heel Length 

 Age. (CH), or Standing 



Height (mm.). 



Twenty-one days 0.5 



Twenty-eight days 2.5 



Thirty-five days 5.5 



Forty-two days 11.0 



Forty-nine days 19.0 



Second lunar month 30.0 



Third lunar month 98.0 



Fourth lunar month 180.0 



Fifth lunar month 250.0 



Sixth lunar month 315.0 



Seventh lunar month 370.0 



Eighth lunar month 425.0 



Ninth lunar month 470.0 



Tenth lunar month 500.0 



