1918] SARGENT—TILIA 437 
The unusual whiteness of the under surface of some of the leaves of this 
variety is due to a thick bloom. When this is rubbed off, the surface left is 
pale green. This bloom appears to be most common on leaves near the ends 
of branches and is often entirely wanting from those lower down on the 
branches and from the leaves of young vigorous shoots. 
7. Tilia Cocksii, n.sp.—Leaves ovate, abruptly acuminate at 
apex, very oblique at the truncate or rounded base, dentate with 
small, remote glandular apiculate teeth; when they unfold covered 
with loose floccose pubescence, nearly glabrous when fully grown 
early in April; when the flowers open, dark green, and lustrous on the 
upper surface, pale blue-green and lustrous below, and at mid- 
summer when the fruit ripens, subcoriaceous, dark green and 
lustrous on the upper surface, paler on the lower surface with 
slender primary veins without or occasionally with minute axillary 
tufts, and connected by conspicuous straight or curved veinlets, 
g-1o cm. long and 6-7 cm. wide; petioles slender, glabrous, 1.5— 
2.5 cm. in length; leaves on leading summer branchlets sometimes 
obliquely cordate, more coarsely serrate, covered on the upper 
surface with short fascicled hairs, and floccose-pubescent on the 
lower surface, 10-13cm. long, 1o-12cm. wide, their petioles 
puberulous. Flowers 6-7 mm. long, on tomentose pedicels, in 
compact pubescent many-flowered corymbs; peduncle slender, 
glabrous, the free portion only 1.5-2cm. in length, the bract 
oblong, occasionally slightly obovate, rounded at the ends and 
sessile, hoary tomentose on the under surface and pubescent on 
the upper surface when it first appears, and when the flowers open 
puberulous below and glabrous above, 1.2—-1.5 cm. in width and 
much longer than the peduncle; sepals ovate, acuminate, pale 
pubescent on the outer surface, villose at the base on the inner 
surface, a third shorter than the lanceolate acuminate petals; 
staminodia oblong-obovate, rounded at apex, about half the length 
of the petals; style glabrous. Fruit globose to depressed-globose, 
covered with loose brown tomentum, 6-7 mm. in diameter. 
A small tree with slender, dull red, glabrous branchlets, the leading branch- 
lets in summer more or less pubescent. Winter buds ovate, acute, dull red, 
glabrous or pubescent on leading shoots, 5-6 mm. long. Flowers the middle 
of May. Fruit ripens the middle of July. 
