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IOWA ACADEMY OP SCIENCE Vol. XXIV, 1917 
nent, trichomes few on upper and lower surface of leaf, on very 
young leaves more numerous than when fully formed, singly 
or bunched, in some cases as many as live trichomes in a cluster, 
long pointed, cell walls thick, white, upper surface with similar 
trichomes^ but less in number, either singly or from two to four 
cells in a group. By May 10 these oak seedlings were from four 
to seven inches in height, averaging three and one-fourth inches. 
Post Oak ( Quercus stellata Wang.). The acorns were sent to 
us from Johnson City, Tennessee, by J. PI. Frazier. They were 
planted in the greenhouse on October 29 in sandy humus, . cov- 
Fig. 68. — Germinating post oak ( Quercus stellata), planted in October; 
1, condition on November 10 ; 2, condition on December 5 ; 3, trichomes of 
stem ; 4, trichomes of leaf. Drawn by C. M. King. 
ered with damp sphagnum. The germination is hypogaeous and 
occurs soon after the acorns fall from the tree. The hyipocotyl 
pushes its way through the acorn at the apical end. The hypo- 
cotyl is strong; it soon becomes thickened and is woody. On 
December 5 it was somewhat longer than the acorn. Growth 
was much slower than in the white oak. The plumule emerges 
near the basal end of the hypocotyl. The young stem is pu- 
bescent, trichomes occurring singly or in (dusters of two, straight 
