DIMENSIONS OF KIDNEY 



449 



obtained for the measurements for each body length by multiplying the three dimen- 

 sions together and dividing the product by 10,000 in order to bring the number to a 

 manageable size. These numbers (kidney numbers) do not, of course, represent volume, 

 but size, and have no absolute but a comparative value. Even the comparative value of 

 them is somewhat limited since kidneys with a greater depth than usual, but perhaps a 

 smaller length, will have a disproportionately large size number and vice versa. In 

 general, however, these numbers will give a fair representation of the sizes of the kidney. 

 In Fig. 35 the kidney numbers are shown plotted against the body lengths. The 

 kidney numbers are derived from the figures given in Table I. Only Fin whales have 

 been dealt with, since the numbers of Blue whales examined for each body length were 

 too small. 



14 15 16 17 



Length of Body (Metres) 



Fig. 35. Adult Fin whales. Length of body and kidney numbers (left kidney). 



The figure resulting from the plotting of the body lengths against the kidney numbers 

 is a straight line. The points for both sexes (• = male, o = female) fall upon the same 

 line. The growth rate is the same, then, in both sexes, and for a given increment in the 

 body length there will be the same increment in the size of the kidney at all stages during 

 the growth of the body. The growth rate of the kidney is even and continuous until full 

 physical maturity, when the body ceases to grow. Further, as seen from Table I A (and 

 II a for Blue whales), the growth of the kidney consists in an increase in length primarily, 

 breadth secondarily and depth scarcely at all — a feature of the growth of this organ 

 commented upon by Beauregard and Boulart and by Daudt. The length of the organ is 

 dependent upon the length of the body, while the other two measurements appear to be 

 related to the girth of the body. 



