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PHYSIOLOGY FOR DENTAL STUDENTS. 



ferent, the thyroid having to do with the general nutrition of the 

 animal, and the parathyroid with the condition of the nervous 

 system. They lie so close together, however, that it is very diffi- 

 cult to study their separate functions. The importance of the 

 glands is indicated by the relatively large blood supply. 



Fig. 10. Cretin, 19 years old. The treatment with thyroid extract was 

 started too late to be of benefit. (Patient of Dr. S. J. Webster.) 



When the thyroid is not properly developed in children, the 

 condition is known as cretinism (Fig. 10). The child fails to 

 grow in height, although its bones may thicken. It cranial bones 

 soon fuse together, so that the growth of the brain is hindered 



