1921] PACK—JUNIPERUS : 35 
Fig. 1 shows the structure of the seed of J. virginiana, with its 
many membranes and protective layers. In strong contrast with 
the hard brown coat are the clear white endosperm and embryo. 
The hard coat consists of three layers: the outer fleshy (a), the 
stony (b), and the heavy inner fleshy (c), In the outer fleshy 
layer are found pectic substances and methyl pentosans. The 
stony layer is lignified and contains other substances, as calcium, 
pectates, and pentoses. The inner fleshy layer is well developed 
and consists of suberin with some little cellulose. Of the endosperm, 
embryo, etc., one distinguishes the nucellus (d), the mass of dis- 
torted tissue (e), the hypocotyl cap (/), the megaspore membrane (/), 
the endosperm wall (k), the endosperm (g), and the embryo (/). 
TABLE II 
PERCENTAGE OF IMPERFECT SEEDS IN LOTS I, 3, 4, AND 5 
Species Lot No. examined Percentage imperfect 
ce Mek were eee en I 100 59 
z Mth, ob tae unt a Oe ee ere I 50 63 
g Vibe oo CA ia I 100 61 
g. Vigna ss a a. I 2000 
J, Conn ee 3 1000 26 
gp: Petetinth | eae: 4 1000 20 
Fe Ven ee ices 5 2000 22.5 
The nucellus is constructed of long narrow cells which give tests for 
cellulose and pectic acid. The mass of tissue (e) protecting the 
hypocotyl consists of cellulose, pectic substances, and some other 
groups of substances such as fats and gums. Between this. mass 
and the hypocotyl is a cap of very fine and firm cells (z), which are 
made up of cellulose and hemicellulose. The megaspore mem- 
brane (7) is very thin and stains with ruthenium red. Examination 
shows that the outer wall of the outer layer of endosperm cells 
has been developed into a suberin wall (k). This wall is insoluble in 
concentrated H,SO,, 50 per cent chromic acid, and gives the phellic 
acid reaction. The endosperm cell walls are rather thick and 
made up of cellulose. Cell walls of the embryo are thin and con- 
sist of pectose and cellulose. 
