55o 
Fruit  of  Cocos  Nucifera. 
/Am.  Jour.  Pharm. 
I  November,  1901. 
tracheae  (sp.),  and  pitted  tracheae  (g),  the  latter  being  especially 
noticeable. 
4.  Testa. 
Several  microscopists  have  studied  the  testa,  but,  owing  doubt- 
less to  differences  in  the  material,  hardly  two  of  them  agree  as  to 
the  number  of  coats  or  the  character  of  the  elements.  The 
description  which  follows  is  based  on  the  examination  of  numerous 
specimens. 
Fig.  10.  Tangential  section  of  the  onter  testa  of  the  cocoanut  showing  the 
ground  tissue  of  thick-walled  porous  cells.  Most  of  these  are  empty,  but  a 
few  contain  brown  contents  in  the  form  of  globules,  (k)  or  films  with  circular 
openings  (v).    st,  colorless  stone  cell  ;  sp,  spiral  trachea.    X  300. 
(a)  Outer  testa.  This  coat  consists  of  a  ground  tissue  of  large, 
variously  shaped  cells,  crossing  one  another  in  all  directions  (Fig. 
8,  7]  Fig.  10),  between  which  ramify  the  veins. 
Most  of  the  ground  tissue  cells  have  colorless  double  walls,  from 
•004  to  'Oio  m.m.  thick,  with  conspicuous  (sometimes  large)  pores, 
but^in  the  inner  layers  they  often  have  thinner  walls  without  evi- 
dent pores  and  except  for  their  shape  bear  no  resemblance  to  the 
other  cells. 
