Chemico-FiMictional Integration 123 



the plain muscle of the blood vessels and inhibition of that 

 of the intestines. 12 The distinction has an undoubted natu- 

 ral grounding, and so is in the interest of accurate descrip- 

 tion and clear conception. 



As to the actual chemical composition of internal secre- 

 tions, knowledge is exceedingly meager. More is known 

 about adrenaline, the active principle of the suprarenal 

 gland, than about that of the secretion of any other gland 

 or tissue. This was isolated by the Japanese chemist 

 Jokichi Takamine in 1901, and has since been more fully 

 examined by several investigators, notably by T. B. Aldrich. 

 It is described as a micro-crystalline substance occurring in 

 at least five crystal forms. Aldrich assigns to it the em- 

 pirical formula CgHjoNO.^, this structure placing it not far 

 from tyrosin in the benzene or aromatic series. Of special 

 interest is the astonishingly minute quantites which produce 

 physiological effects. According to Aldrich 0.000001 gram 

 of an aqueous solution of the chloride per kilo of body 

 weight injected into the blood system raises the blood pres- 

 sure 14 mm. of mercury. 13 



The chemical nature of Tethelin, lately isolated from the 

 anterior lobe of the pituitary of the ox, has been studied 

 by its discoverer, Robertson. It is described as white or 

 pale cream colored, readily powdered, highlv deliquescent, 

 and having a greasy odor and slightly acid reaction in 

 aqueous solutions. It contains 1.4 per cent of phosphorus 

 and four atoms of nitrogen for every atom of phosphorus. 

 The phosphorus-nitrogen content of the substance is con- 

 sidered by Robertson as specially significant, since this 

 seems to ally it chemically with "phytin," a substance found 

 in the rapidly growing parts of plants, and in milk. The 

 natural suggestion is that the growth-promoting substances 

 in plants, milk, and the pituitary secretion are chemically 

 related. 



