Natural size 

 photographs of 

 salamanders show- 

 ing effect of diet 

 upon growth. The 

 top animal was fed 

 beef liver, the 

 middle one anterior 

 lobe and the bottom 

 one earthworms. 



^ 



EXPERIMENTAL GIGAII 



E. Uhlenhuth, Rockefeller Instu 



I 



tSe^ 



Allh(nl^^h certain facts, such as the con- 

 siderable enlargement of the anterior 

 lobe of the hypoj^hysis in himian gigan- 

 tism and in acromegaly, have made it almost 

 certain that the pituitary body plays some 

 important r6le in the phenomena of over- 

 growth and in growth in general, it has 

 not been possible to produce gigantism in 

 animals by feeding anterior lobe. So far, 

 in the experiments of feeding pituitary 

 only warm-blooded animals have been 

 emi)loycd. If, however, anterior lobe of 

 the h\pophysis is fed to the cold-blooded 

 Sidamanrler, Ambyslnma ti^rinum, a con- 

 siderable overgrowth is secured. 



This fact is illustrated by the accom- 

 panying figure, which shows three male 



salamanders of the same brood and age, taken from a large number of feeding experiments per- 

 formed on this species of animals during the last three years and giving essentially the same 

 results. A different ff)od material was fed to each of these three animals, each one rejiresenting 

 the largest individual of a group of similarly fed animals. The miildle animal was fed anterior 

 lobe of hypophysis, the bf)ttom one a normal diet (earthworms) and the top one beef liver. It 

 will be seen at the first glance that the anterior lobe-fed animal is, by far, the largest one; its 



