34 
Wells a analyzed the thyroids of six children from Chicago under 4 
years; three had but traces, the other three from 0.011 to 0.092 per 
cent. Yon Rositzky 6 reported analyses of the thyroids of eight 
children under 10 years of age; the percentage of iodine varied from 
0.012 to 0.041. Oswald 0 found in five children from Basel under 
7 years from traces to 0.061 per cent iodine. Charrin and Bourcet d 
found in the thyroid of infants under 3 months who were born of 
healthy mothers from 0.0004 to 0.0054 per cent iodine. In many 
cases in which the child or mother had suffered from various diseases 
no iodine was found. Mendel e found no iodine in the thyroids of 
four infants; that of a fifth contained 0.07 mgm. John A found in 
twenty-seven infants in Sweden under 4 years no distinct traces of 
iodine in seven cases and from traces to 0.086 per cent in the others. 
Nagel and Roos* 7 found no iodine in the thyroids of four new-born 
puppies. 
The following experiments were performed with the iodine free 
preparations described above. A few experiments with thyroid 
containing various amounts of iodine are quoted for comparison. 
In all cases the dried and powdered gland was used. 
Series I. 
A. THYROID OF CHILDREN; FREE OF IODINE. 
Date. 
Weight 1 
of mouse. 
1906. 
February 24 
22.06 
March 3". 
22.85 
6 
22. 15 
7 
February 24 
17.22 ! 
March 3 1 
18.05 
6 
17.75 
7 
Remarks. 
Feeding of cakes each containing 0.05 gm. thyroid begun. 
Acetonitrile, 17.72 mgms., i. e., 0.8 mgm. per gm. mouse. Survived. 
Acetonitrile, 26.58 mgms., i. e., 1.2 mgms. per gm. mouse. Survived. 
Thyroid as above. 
Acetonitrile, 17.75 mgms., i. e., 1 mgm. per gm. mouse. Survived. 
Acetonitrile, 24.85 mgms., i. e., 1.4 mgms. per gm. mouse. Survived. 
B. CONTROLS. 
1906. 
February 21 
20.75 ! 
Cakes without thyroid. 
March 3 1 
6 
19.85 i 
18. 75 
Acetonitrile, 5.63 mgm., i. e., 0.3 mgm. per gm. mouse. Died 2 hours. 
February 21 
22. 71 
. Cakes without thyroid. 
March 3. 
6 
22.55 
20.95 
Acetonitrile, 7.33 mgms., i. e., 0.35 mgm. per gm. mouse. Died 1 to 3 hours. 
February 21 
23. 71 
Cakes without thyroid. 
March 3 
6 
25.35 
24,45 
Acetonitrile, 12.23 mgms., i. e., 0.5 mgm. per gm. mouse. Died 1 hour. 
a H. G. Wells, J. Am. M. Ass., Chicago, 1897, 29, p. 955. 
f>A. v. Rositzky, Wien. klin. Wchnschr., 1897, 37, p. 823. 
cA.. Oswald, Ztschr. f. physiol. Chem., Strassb., 1897, 23. p. 291. 
d A. Charrin and P. Bourcet, Compt. rend. Acad. d. sc., Par. 1900, 130, p. 945. 
<L. B. Mendel, Am. J. Physiol., Boston, 1900, 3, p. 287. 
/ S. Jolin, Festschrift O. Hammarsten, LJpsala, 1906. 
g W. A. Nagel and E. Roos, Arch. f. (Anat. u.) Physiol., Suppl. Bd., 1902, p. 275. 
