PRENATAL GROWTH OF THE PIG 



117 



DISCUSSION OF THE DATA AND COMPARISON WITH GROWTH 



IN OTHER SPECIES 



In the following pages, the body as a whole will first be consid- 

 ered, followed by a discussion of the viscera as a whole, and finally 

 of each individual organ. Comparisons are made principally 

 with the human species, for which the data are fairly complete. 



1518 25 39 



58 84 107 130 



Body LenQth in Millimeters 



Fig. 2 Curves showing the relative growth of the Wolffian bodies, heart, 

 kidneys, stomach and intestines with contents and stomach and intestines 

 empty. These curves were secured by arranging the average percentage (for 

 the litter) which the organs form of the net body weight, according to the aver- 

 age body length (in millimeters). In certain cases, several litters are com- 

 bined, the average of the litter averages being taken (see above). The broken 

 line at the right shows the trend of the post-natal relations, as indicated by the 

 observations on the adults. The information thus gained is only general, as 

 there are no indications concerning the age of the specimens, or the rapidity 

 with which the changes take place. 



The figures for the human embryo are quoted from Jackson ('09), 

 unless otherwise specified. Relatively few observations are 

 available for other animals. 



