ADeclmhef^t}         Powdered  Vegetable  Drugs.  621 
6.  Sklerenchyma  cells  or  fibres  zv  anting. 
565.  Aurantii  Amari  Cortex. — See  No.  206. 
566.  Aurantii  Dulcis  Cortex. — See  No.  207. 
567.  Gentian. — See  No.  467. 
568.  Limonis  Cortex. — See  No.  208. 
569.  Sambucus. — Numerous  smooth  pollen  grains  (18x18  /x) ; 
cells  of  anther;  sometimes  find  small  crystals  of  calcium  oxalate 
in  calyx  ;  fragments  of  corolla  with  characteristic  slight,  dentate, 
papillae  ;  in  flower  stalk  are  large  spiral  ducts  (30  /jl  diameter) ;  also 
parenchyma,  with  brown  contents  and  collenchyma, 
570.  Sassafras  Medulla. — Consists  only  of  parenchyma  cells, 
whose  walls  consist  of  cellulose  and  mucilage,  and  hence  swell  per- 
ceptibly in  water.    Mount  sticky,  mucilaginous. 
571.  Taraxacum. — Characteristic  (not  lignified)  "  Ersatzfasern," 
laticiferous  vessels  and  inulin.    See  No.  165. 
572.  Zeal- — Style  with  spiral  and  annular  ducts,  and  from  the  epi- 
dermis there  arises  secretion  hairs  which  are  300  /ul  long. 
II.    CONTAINING  FEW  FRAGMENTS  OF  TISSUES. 
A.     POSSESSING  OIL. 
573.  Asafelida. — In  a  glycerin  mount  the  powder  shows  irreg- 
ular grayish  (or  gray  streaked  with  brown)  masses ;  opaque  and 
becoming  milky  white  on  edge  from  oil.  The  Stony  asafetida  is 
pulverulent  and  contains  less  oil. 
574.  Myrrh. — In  glycerin  mount  powder  appears  in  yellowish  or 
yellowish-brown  irregular  fragments  made  up  of  a  grayish  matrix 
and  containing  yellowish  or  yellowish-brown  oil  globules. 
B.     NO  OIL  ;   AND  GLYCERIN  MOUNTS  NEARLY  TRANSPARENT. 
575-  Manna. — Collection  of  long,  transparent  tetragonal  or  pris- 
matic crystals  of  varying  length  and  about  4  to  10  fjt  wide;  frag- 
ments in  glycerin  leave  clear  crystal  and  little  amorphous  opaque 
residue. 
576.  Fix  Burgundica. — More  pulverulent  (M.  P.  lower)  than 
Terebinthina;  lemon-yellow  transparent,  or  grayish,  somewhat 
translucent,  more  or  less  rounded  and  opaque  masses.  Soluble  in 
glacial  acetic  acid,  giving  a  yellowish-brown  solution. 
