120 
The  Pineal  Gland. 
f  Am.  Jour.  Pharm. 
\      March,  1915. 
On  account  of  the  difficulties  attending  experimentation  on  this 
vestigial  organ,  the  clinical  findings  with  subsequent  necropsy  records 
have  been  the  prime  factor  in  the  formulation  of  the  prevailing  ideas 
as  to  this  gland's  functions.  The  conception  of  this  gland's  function, 
however,  has  in  part  been  developed  from  laboratory  studies,  notably 
from  the  results  concomitant  to  the  extirpation  of  the  organ.  This 
has  been  attempted  frequently,  but  the  situation  of  the  gland  is  such 
that  in  the  greater  number  of  instances  death  followed  the  operative 
procedure,  from  hemorrhage  or  injury  to  the  vermis  or  the  occipital 
lobes.  By  operating  on  a  large  number  of  animals  some  workers 
have  had  a  few  animals  survive.  No  changes  attended  the  removal 
of  the  gland  by  Biedl,4  Dandy,5  and  Exner  and  Boese,6  but  Foa,7 
ablating  the  gland  in  chicks,  and  Sarteschi 8  in  young  rabbits  and 
puppies,  report  the  production  of  the  precocious  macrogenitosomatic 
syndrome. 
The  publications  growing  out  of  these  several  clinical  and  labora- 
tory studies  have  given  rise  to  conceptions  of  this  organ  and  its  func- 
tions that  may  be  thus  epitomized : 
The  pineal  body  (epiphysis  cerebri),  probably  the  remains  of  a 
parietal  eye,  is  situated  just  beneath  the  splenium  of  the  corpus 
callosum,  resting  on  the  anterior  quadrigeminate  bodies,  and  is 
attached  by  its  base  to  the  habenular  commissure.  The  gland  varies 
in  size,  shape,  and  pigmentation,  and  does  not  stand  in  any  propor- 
tional relation  to  the  size  of  the  brain  or  size  of  the  body.  The 
pineal  body  contains  glandular  elements,  but  these  are  few  and  not 
well  defined.  The  greatest  postnatal  development  is  in  the  first  years 
of  life,  and,;so  far  as  is  known,  the  gland  is  only  functionally  active 
in  the  prepuberal  life.  On  the  assumption  that  tumors  destroy  the 
gland  and  deprive  the  body  of  the  substances  generated  by  it,  the 
function  of  the  gland  is  generally  described  as  retarding  and  holding 
in  abeyance  too  rapid  development  in  childhood,  of  the  body,  mind, 
and  sexual  characteristics.  When  precocity  in  development  appears 
in  conjunction  with  pineal  tumors,  it  is  attributed  to  lack  of  glandular 
secretion. 
4  Biedl :  "  Innere  Sekretion,"  1910. 
5  Dandy,  cited  by  dishing :  "  Pituitary  Gland  and  Its  Disorders,"  p.  283. 
6  Exner  and  Boese :  Deutsch.  Ztschr.  f.  Chir.,  1910,  cvii,  182. 
7  Foa:  Arch.  Ital.  de  Biol,  1912,  lvii,  233- 
8  Sarteschi :  "  Pathologia,"  1913,  p.  707. 
