194 GLANDS IN HEALTH AND DISEASE 



plant, have been explained ; but all this is, at pres- 

 ent, largely fancy and little more. 1 



1 Mention may here be made of a more direct experiment by 

 Dr. Budington, of Oberlin College. He experimented with sound 

 onion bulbs which were placed in a nutrient solution to which 

 small quantities of glandular extracts from the thyroid, the 

 adrenal and the pituitary were added. A certain amount of 

 "retardation" in the growth of root tips when thyroid extract 

 was used, and marked modifications of growth when iodine in 

 the form of potassium iodide was used, were obtained. "While 

 no general conclusion can be based on experiments limited to a 

 single form, the indication is that thyroid constituents and it 

 will be remembered that iodine is such a constituent may in- 

 fluence the role of protoplasmic action in cells other than those 

 of animal tissues." 



