6 Marshall Ward and Dunlop . 
the remains of the nucellus. In the dry state all the parts 
are shrunken, and a large hollow cavity exists on the dorsal 
side of the endosperm— between it and the testa. The various 
parts of the fruit were then separated and sections cut so as 
to exhibit their structure. The outer pericarp is brittle and 
waxy in texture : their sections, in the dry state, show (Fig. 5) 
an outer epidermal layer, the external cell-walls of which are 
strongly cuticularised. With the exception of certain small 
granules, looking very like plastidia, these cells and those 
immediately below them have no contents. Immediately 
below the epidermal layer are four or five rows of hypodermal 
cells, the outer rows consisting of regular rectangular cells, 
which in the inner rows become less and less regular and 
smaller, all however containing small corpuscles near the 
interior of their walls. These seem to be chlorophyll-cor- 
puscles. Below these cells are larger, thin-walled, parenchy- 
matous cells containing a yellow amorphous substance which 
completely filled up the cavity of the cell (Figs. 5 and 6 ). 
Water was then added to the dry sections while still under 
the microscope ; the cell-walls, etc. swelled up and the yellow 
substance in the cells at once dissolved completely, colouring 
the water yellow and leaving the cavities of the cells empty ; 
the latter were then seen to be thin-walled and parenchyma- 
tous (Fig. 5). 
To other dry sections under the microscope glycerine was 
added ; they again swelled up and the yellow substance in 
the parenchymatous cells again dissolved, but not so rapidly 
as in water. Sections were treated in a similar manner with 
alcohol, chloroform and ether ; the yellow substance dissolved 
to a very slight extent in alcohol, but was insoluble in chloro- 
form and ether. Thus the yellow substance was not a wax, 
resin or fat, any of which would probably have dissolved in 
any of the last three reagents, and not in water or glycerine. 
The histology of the endocarp was next made out. Its 
inner yellow lining was stripped off and examined ; it was 
found to consist of a layer of long thin-walled cells containing 
a yellow waxy- looking substance, and on adding water the 
