THE INFLUENCE OF THE DUCTLESS GLANDS UPON 
M KTABOLISM— INTERNAL SECRETIONS. 1 
By E. A. Schafer. 
Contexts :— Introductory, p. 937— The Thyroid Gland, p. 938— The Pituitary Body, 
p. 945 — The Suprarenal Capsules, p. 948 — The Spleen, p. 959. 
Certain organs of the body have a special influence upon some of the 
metabolic processes of the body. Thus the liver fulfils important 
special functions in connection with the metabolism of carbohydrates 
and proteids, and of those organic compounds which contain iron ; 
the pancreas has an obscure but absolutely essential function in con- 
nection with carbohydrate metabolism ; and removal of a large portion 
of the kidneys has been shown by Bradford to produce a large increase 
in the proteid waste of the tissues. 2 It is also a matter of common 
knowledge that removal of the ovaries or testicles may produce 
profound modifications in the development of other organs, and in the 
general nutrition of the body. In the case of the pancreas (and perhaps 
in that of the kidney) it is by no means improbable that the gland 
yields to the blood some material which influences the carbohydrate 
(and nitrogenous) metabolism of other tissues. In the case of the 
generative glands this is perhaps less probable : it is on the whole 
more likely that these react upon the rest of the organism through the 
nervous system. Numerous observations have of late been published, 
commencing with those of Brown-St'quard, which have seemed to indicate 
that extracts of or the expressed juices of these glands produce, when 
injected hypodermically, beneficial effects upon the nervous and muscular 
systems, but it is not clear that this property is not shared by other 
organs rich in nuclein. Watery extracts or decoctions of the generative 
glands have very much the same action, if injected into a vein, as have 
extracts of other glands. In addition to the above instances, there are 
certain organs of a glandular structure, but destitute of ducts, which 
yield to the blood substances, which are in some cases at least 
absolutely essential to the due nutrition of the body, so that the results 
of the complete removal of these organs is inevitably fatal. These 
substances are no doubt formed by a process of secretion, but since they 
do not find then' way to any free surface by means of a duct, but 
1 The substance of this chapter was originally given in the form of an address to the 
British Medical Association, and was published in the British Medical Journal for August 
10, 1895. For the purposes of this book it has been carefully edited and many additions 
have been made to it ; references to literature have also been appended. 
2 Proc. Roy. Soc. London, 1892. vol. li. These researches of Bradford have already 
been noticed in a previous article (p. 656). See also Meyer, Arch, dephysiol. norm, etpath., 
Paris, 1894, p. 179. 
