THE THYROID AND PARATHYROIDS 305 



FIG. 88. Photograph of group of thyroidectomized sheep taken five months 

 after operation (after Simpson Quart. J. Exp. PhysioL). 



result of a similar operation, three lambs about two months old 

 became "typical cretins." 



The complete operation (thyro-parathyroidectomy) in four 

 young lambs (five to seven weeks old) resulted early in acute 

 and fatal tetany. Removal of the two external parathyroids 



FIG. 89. Photograph of cretin lamb about one year old, and of normal 

 lamb of eleven months (after Simpson Quart. J. Exp. PhysioL). 



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