Parathyroid Tetany and Active Immunity. 



187 



In general the adult pregnant female weighing 3-3.5 K. has 

 thyroids weighing (fresh) 0.20 g. to 0.30 g. While thyroid hyper- 

 plasia has not yet been found in pregnant cats, it is a striking fact 

 that mothers with relatively large thyroids give birth to kittens 

 with relatively large thyroids and vice versa. The following 

 figures may be cited as typical : 



Ratio of thyroid to body weight. 

 Mother. Kittens. 



No. X 1-16,250 1-7,326 



No. IV 1- 4,680 1-2,000 



The results so far point to the following conclusions: 



1. Active thyroid hyperplasia is not associated with hyper- 

 secretion of the thyroids, because hypersecretion of the thyroids 

 in the mother would retard rather than augment thyroid growth 

 in the fetus. 



2. Since fetal goiter is always present in the offsprings of 

 mothers with active thyroid hyperplasia, and never present in the 

 offsprings of mothers with normal thyroids or colloid goiter, it 

 would seem that the fetal goiter is not due primarily to the condi- 

 tion of the germ cells, but to some intoxication of the mother or 

 altered condition of the maternal metabolism. Since the maternal 

 environment acts on the fetus only by the way of the blood, the 

 goiter must be due to substances in the blood acting alike on the 

 fetal and the maternal thyroid to produce cell division and growth, 

 rather than specific thyroid differentiation and secretion. This 

 hyperplasia is therefore not compensatory. 



118 (814) 



Parathyroid tetany and active immunity. 



By A. J. Carlson. 



[From the Hull Physiological Laboratory of the University of 



Chicago.] 



Parathyroid tetany in dogs seems to be associated with dimin- 

 ished resistance to bacterial invasion of the mucous membranes, 

 as shown by the frequent infection of the eyes, the nose, and the 

 respiratory passages. This diminished resistance may be due to 

 (1) depression of the processes of active immunity; (2) local de- 



