arn 4 = % Migs 2 Tg eee &: 
BURSERA OnE. 
_ Cells containing plenorhombic crystals of caleinm oxalate are’ %S 
_ very numerous next the corky layer. Further within the bark 
- are cells containing small oval or oblong starch grains giving — 
a well defined cross with polarized light. The undulating a 
medullary rays, composed of 2 or 3 rows of radially elongated — 
¢ells, divide the liber into narrow wedges. The large, oval, a : 
intercellular secretory reservoirs which contain the milky, fluid. 
are mainly distributed in this layer in three or four interrupted 
and not very regular tangential rows. The lumen has an " 
average measurement of 100 mkm., and is surrounded by two ; 
“or three rows of secreting cells. A few secreting reservoirs — e 
occur in the outer bark, but they are not met with in oc 2 
wood nor in the medulla. 
Interspersed through the bark and sometimes fovmiiipen an 
: Minin, « and the bast fibres paces bifurcate. 
lary rays are composed of two or three rows of cells from six 
oe twenty deep and not arranged in parallel rows. fe 
According to the account of the Swiss traveller, G. Avi 
-Baggenmacher,* the bark is used by the Somalis for tanning. 
Assayed for tannin by Léwenthal’s permanganate and gelatine 
Process, and observing the details recommended by H. R, 
Proctor ; 4°7 c. c. permanganate solution, 1 gramme per litres. 
_ Was potednsad by 20.c. c. of a decoction representing 2 
_ gramme of dry bark. Expressed in terms of oak bark using ¥ 
‘Oser’s equivalent, these results give 4°7 per cent tannit 
xtracted by boiling water. 
he 
: ae 
Description.—Olibanum as found in commerce 
nf Dated aby Pliokiger, Pharm. Journ, | 7 
