FIELDS, GRAPHS, AND OTHER DATA ON FETAL GROWTH. 



65 



In figure 5 the number of deliveries per day are plotted, beginning with 260 days. The 

 numbers above indicate the total number of cases for each day. Here, too, the large number 

 of cases with a long duration is evident. 



Figure 4 gives the curves of growth of weight of Hennig and myself. The former is 

 based on 100 cases, the latter on 229. Neither is carried beyond 2,500 grams, because 

 that is where Hennig's curve stops. The peculiar disagreement between these curves 

 between a weight of 1,250 and 1,750 grams is puzzling. However, I am inclined to regard 

 Hennig's curve as probably the more defective, for it is based on a comparatively much 

 smaller number of cases and also because we know that a rapid increase in weight occurs 

 between a weight of 1,300 and 2,300 grams. Nevertheless, the sharp increase and decline in 

 my curve are probably also incorrect and due to a too narrow statistical basis. 



Figure 6 represents various curves of length. Those of Toldt and Mall are drawn 

 after Mall (1910), page 200. Here the close correspondence between the character and 

 location of the curve of Hennig, that of Shroeder-Ahlfeld as given by Stratz (1909), which 



22 20 24 35 50 



Duration in days 



Number of deliveries daily between 260 and 340 days. The figures above represent the exact number of deliveries 

 indicated on that point on the graph. 1,949 cases. 



coincides with that of Stratz (1910), and my curve is evident. The fact that my graph 

 lies to the left of all the others, including that of Hecker and Michaelis,is difficult to explain, 

 except upon the assumption that the other curves were based on averages, while my curve 

 is a median. Not that I assume a definite mathematical relationship between the average 

 and median values; for as far as I can see it is impossible to decide in advance what their 

 relation in a given case is. An inspection of the fields might help to suggest where both lie, 

 but their exact location could be determined only by calculation. As far as Toldt's curve 

 is concerned, his confusion of two measurements, as Mall (1907) pointed out, affects Toldt's 

 curve in its lower segments only — below an age of \\ months — and can hence be ignored 

 here in the comparison of my curve and Toldt's. However, since I suggested above that 

 my series of cases included too many with a long duration, it may be urged that my graph 

 should consequently be displaced to the right instead of to the left, where it is actually 

 found. Nevertheless, I consider that this effect would be but a slight one and would not 



