THE PITUITARY GLAND 61 



ens. One rather remarkable experiment with 

 chickens, performed by Dr. L. N. Clark, must be 

 cited: "In the first experiment, 35 white Leghorn 

 hens, as well as two cockerels of the same breed 

 with which they were mated, each received daily 

 during eight days the equivalent of 20 milligrams 

 (0.0006 ounces) of fresh pituitary substance in 

 addition to their usual food. By the fifth day the 

 egg production of the batch was raised from an 

 average of 18 per diem to 33 ; the beneficial effect, 

 although diminishing, was maintained for several 

 days after the pituitary had been taken off. And 

 not only was the output of 'eggs largely f increased 

 as compared with the controls, but the fertility of 

 the eggs and the hatching out of the chicks was 

 extraordinarily enhanced. In order to test the 

 matter further, a second experiment was performed 

 with as many as 655 one-year-old white Leghorn 

 hens (kept without males), the same dose as be- 

 fore being given to each hen during four days. The 

 average daily number of eggs laid by the batch 

 during the four days preceding the pituitary feed- 

 ing was 233; during the four days succeeding the 

 administration, 352. These experiments were made 

 at a time of the year when the egg production of 

 the hens was tending to diminish rather than to 

 increase." ( Quoted by Professor - Schafer. ) 



Hyper-pituit&rism* Marie, a French physician, 

 active some forty years ago, was the first to give 



