174 
PA THOLOG Y : BERG A ND KELSER 
It is only to be regretted that this step was not taken earlier, for the large 
number of idle bulls now in the herd is both a detriment to that body and a 
positive loss of once good skins. This menace in the growth of the herd has 
been repeatedly pointed out (Clark, 1914, 1916, 1917; Osgood, Preble, and 
Parker, 1915) to those having the matter in charge. 
The last column in table 1 contains the estimated annual totals for the 
herd. These numbers are highly artificial in that they are largely made up 
of computed elements and they are, therefore, so remote from direct ob- 
servation that their detailed consideration is scarcely worth while. The 
fact that all elements of the herd have separately increased between 1912 
and 1917 is reflected in the increase of these calculated totals from 215,738 
in 1912 to 468,692 in 1917. 
In conclusion it may be stated that since 1912 the steady increase in the 
numbers of pups born, and of harem bulls and the decrease since 1913 of 
the average harem are most favorable signs in the growth, of the herd. The 
one unfavorable feature during this period is the considerable increase in 
idle bulls in 1915, 1916, and especially in 1917. This increase, which can be 
eventually checked, shows that active commercial killing should have been 
restored some years ago. 
Anonymous, Washington, Fisheries Serv. Bull., No. 30, 1917, (6-7). 
Bower, W. T., and Aller, H. D., Alaska Fisheries and Fur Industries in 1916, Washington, 
1917, 118 pp. 
Clark, G. A., New York, Science, N. S., 39, 1914, (871-872); Ibid., 44, 1916, (608-609); 
New York, Amer. Mus. J., 17, 1917, (497-499). 
Osgood, W. H., Preble, E. A., and Parker, G. H., Washington, Bull. U. S. Bur. Fisheries, 
34, 1915, 1-172, 18 pis., 24 maps). 
Parker, G. H., Philadelphia, Proc. Amer. Phil. Soc, 54, 1915, (1-6). 
Smith, H. M., Washington, Ann. Rep. Comm. Fisheries, 1917. 104 pp. 
THE DESTRUCTION OF TETANUS ANTITOXIN BY CHEMICAL 
AGENTS 
By W. N. Berg and R. A. Kelser 
Pathological Division, Bureau of Animal Industry, Washington 
Communicated by R. Pearl, April 13, 1918 
The ultimate object of this work is a solution of the problem of the chemi- 
cal nature of antitoxins and their preparation in the pure state. That this 
would be attained was not expected in view of the numerous previous in- 
vestigations which left these problems unsolved. But it seemed highly 
probable that data would be obtained which would throw some light on the 
subject. 
Up to the present time numerous investigators attempted to separate anti- 
toxins from their associated proteins, but without complete success. The 
