Prenatal Growth of the Human Body. 



133 



the average percentage taken for all the cases in each lunar month. 

 This is more accurate but more tedious than to divide the sum of the 

 weights of an individual organ by the sum of the corresponding body 

 weights. The latter method was used only in the case of the data by 

 Boyd and Oppenheimer and the lung observations by Schmitt, Dever- 

 gie and Elsasser (cited by Liman). In these cases, the individual 

 data are not available, but the number of observations is so large that 

 the probability of error is reduced. The figures in parenthesis fol- 



4 5 6 



Lunar Months 



Fig. 4. Curves showing relative prenatal growth (percentage of total body' 

 weight) in the kidneys, suprarenal glands, spleen, thymus and thyroid gland. 

 Based upon Table V, from all data available, grouped by months. 



lowing the averages indicate the extremes of variation in relative size 

 for the corresponding period. My own data (Table IV), in terms of 

 volume (cc.) have been added unchanged to the others in terms of 

 weight (g.), although strictly considered they are subject to a slight 

 correction on this account. 



In Figs. 3 and 4, curves are sho^vn illustrating graphically . the 

 relative prenatal growth rate for some of the principal organs. Table 

 VI shows the relative size of the various organs by lunar months, the 



