GROWTH OF SKELETON 187 



The data on the percentage of water in the skeleton and its parts 

 are given in chapter 8. 



Some selected results, entered in forty-two body weight groups, 

 appear in tables 126-131 and Charts 23, 24 and 25. 



Table 126 gives the fresh weights of the entire skeleton and its 

 main divisions on body weight — ^Charts 23 and 24. 



If the percentage weight of the "ligamentous" skeleton for 

 the extremes of body weight as given in table 124 is compared 

 with that for the "cartilaginous" skeleton, table 126, it appears 

 that at a body weight of five grams the cartilaginous skeleton 

 represents only 53 per cent of the value for the ligamentous 

 skeleton, while at 235 grams it represents about the same or 55 

 per cent. Roughly then the proportional weight of the liga- 

 mentous is nearly twice that of the cartilaginous skeleton, ob- 

 tained by this method of maceration. We shall not attempt to 

 adjust these two sets of values, but in table 127 are given the 

 factors for correction of the macerated (cartilagmous) skeleton 

 by which the effect of the maceration can be corrected and the 

 true weight can be fairly approximated. 



It appears from this table that the loss in fresh weight drops 

 from about 16 per cent at birth to about 7.5 per cent at a body 

 weight of 100 grams, and after a body weight of 200 grams the 

 weight of the macerated may be below that of the unmacerated 

 bones — from 4.5 to 3.5 per cent. When, however, the oven-dried 

 weights of these same bones are compared, it is seen that while 

 the losses after oven-drying follow the same course as was 

 followed in the case of the fresh bones, yet the values run very 

 consistently — about 3 to 3.4 per cent (on the average) below 

 those for the fresh bones. 



As the long bones of the limbs are most readily prepared, and 

 as their condition appears to indicate that of the skeleton in 

 general, several tables giving data for them are presented. 

 Table 128 and Chart 25 give the absolute weight of the fresh limb 

 bones on body weight. The corresponding weights for the room 



