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Dicotyledons with Incomplete Flowers — Cupuliferae. 
LEAVES deciduous or evergreen : falling in autumn as in Common Oak ; persisting through the winter and 
falling on the expansion of the leaves in the succeeding spring as in Holm Oak (Q. Ilex) and Luccomb Oak, a 
hybrid derived from Turkey Oak (Q. Gerris). Many species, both American and Asiatic, are evergreen. 
FLOWERS of Common Oak monoecious : staminate each with a simple perianth and 8 or more free stamens ; 
pistillate usually 2 or 3 together, sessile or upon erect axillary peduncles, each flower surrounded by numerous minute 
coherent bracts ; limb of the perianth reduced to microscopic teeth ; ovary surmounted by a 3-lobed style. 
Fruit a nut (acorn), 1 -celled, 1 -seeded with traces of the suppressed cells and ovules on the inside of the pericarp. 
Embryo with a superior radicle and large fleshy plano-convex cotyledons. Acorn in Common Oak with the base 
sheathed by an involucre (cupule) consisting of numerous small, ovate, closely-imbricating, appressed, accrescent 
scales ; in Turkey or Mossy-capped Oak (Q. Gerris) with the scales of the cupule subulate and recurved. Cupule 
various in other exotic species. 
USES, &c.—As a timber tree the Oak is without rival in northern forests in the tenacity and durability of its 
wood, applied to almost every purpose of construction and application in the arts where these properties are required. 
The bark contains a large proportion of tannin and gallic acid, which render it a valuable astringent, generally 
employed as such by tanners. Galls upon the oak resulting from insect-punctures and the acorn-cups of some 
species, as of the Valonia Oak of the Levant (Q. JUgilops), partake of this property in a high degree, and the latter 
are largely imported for tanning and dyeing. It is owing to the presence of gallic acid in the wood that the timber 
of oak is so apt to acquire a black colour when immersed in bogs, from the natural ink resulting from the combina¬ 
tion of the gallic acid of the wood with salts of iron contained in the water. The bark of Cork Oak (Q . Suber), 
growing in South-western Europe and Algeria, is separated artificially from the tree at intervals of 6-10 years after 
it attains an age of about 30 years; it is heated, flattened, and dried for exportation. Quercitron is the bark of 
Q. tinctoria of the United States, used as a yellow dye. Several North American Oaks, as the Red and Scarlet 
Oaks ( Q . rubra and Q. coccinea ), as well as the European Holm and Turkey Oaks, are frequently planted in England. 
II.—GENUS CHESTNUT ( Castanea ).—Though not indigenous in Britain Spanish Chestnut 
