CHAPTER 28 



THE FUNCTIONS OF THE PINEAL BODY 



We do not propose to deal at length with the controversial question of the 

 function of the mammalian pineal organ, which has been very fully dis- 

 cussed in publications specially concerned with the endocrine glands ; 

 nor do we propose in this section to discuss the various functions attributed 

 to the pineal organs of fishes, amphibia, and reptiles, which we have already 

 alluded to (pp. 6, 46, 230) ; but from the practical standpoint of whether 

 the use of pineal extracts as a therapeutic measure should be continued or 

 should be discontinued, we believe that the present time is ripe for a 

 short review of the principal results which have been obtained from 

 recent experimental work on the function of the pineal gland in birds 

 and mammals. 



The evidence which is often contradictory may be classified under 

 two principal headings, namely : 



A — The results of experimental work on animals. 

 B — Observations on the human subject. 



A. Experimental Work on Animals. — The biochemical aspect of this 

 subject has been fully dealt with in numerous articles in the physiological 

 and pharmaceutical journals and is beyond the scope of the present 

 treatise ; we shall therefore limit our description to the consideration of 

 the general results of experimental work under the following categories : 



1. The results of pinealectomy. 



2. The effects of feeding with pineal substance and injection of 



pineal extracts. 



3. The influence of pineal grafts. 



In the consideration of each of these subdivisions we shall allude first 

 to results which are deemed to be of a positive character and afterwards 

 to those which are negative. We shall also limit ourselves to a brief 

 discussion on the more important and typical results which have been 

 obtained by authoritative workers, and we shall not attempt to make a 

 complete record of the numerous papers of an indecisive nature which 

 have been published on this subject, references to which will be found 

 in the larger monographs dealing with the organs of internal secretion 

 and the principal journals on endocrinology. 



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