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brane Î regard as a real, though very reduced sarcotesta 
covered by a hypoderma and epidermus. 
It has been supposed, that these layers belong to the 
sclerotesta the cells not having developed the stony 
character (Dupler, 56). ,It would not be necessary to 
regard a layer or two of cells overlying it (the hard coat) 
as representing the outer fleshy layer . (Coulter and 
Chamberlain, 51). In comparison however, with other 
already described seeds, [| am inclined to maintain my 
opinion. 
The other two layers, the stony coat and the papery 
one are homologous with the sclerotesta and endotesta of 
the other gymnospermous seeds. 
Outside distinctly pronounced ribs are to be distinguished, 
running from the micropyle till half way down the height. 
Their number varies and amounts two, three or four. Àt 
the micropyle sutures underlying the ribs are to be seen 
in transverse sections. The form at the base of the seed 
where it is attached to the axil agrees with the number 
of ribs in the micropylar region, and is oval, triangular 
or square, according respectively to the number of ribs; 
being two, three or four. The following table indicates 
the number of ribs, for the examined species and varieties. 
(See page 65). The number of seeds with two ribs hardly 
dominates over which have three, and those with four 
ribs too are very frequent. 
At the micropyle there are often some lips to be observed 
as in Ginkgo, mostly two in number, but they are not 
always to be seen and when present do not correspond 
with the ribs. 
In a young stage of development the nucellus is entirely 
free from the integument, but after fertilization, when the 
chalazal region has its greatest activity of growth, nucellus 
and integument become united in their lower part. 
