CLASS MONffiCIA. 193 



It derives its name from the leaves, which are of the 

 form of the Arrow-head. The flowers are white, 

 have greatly the appearance of a Ranunculus, being 

 produced on scapes, and grow always by 3's. In 

 both kinds of flowers the calyx is 3-leaved, and the 

 corolla of 3 petals. The stamina are numerous, but 

 said to be definite, or constant to a certain number. 

 In the fertile flowers the germs are numerous ; the 

 pericarps (or apparent seeds) are aggregated, 1 -seed- 

 ed, and do not spontaneously open. There are in 

 the United States 9 or 10 distinct species, and some 

 of them with leaves destitute of the arrow-shape ; 

 yet many have an occasional tendency to put on this 

 form, when their usual leaves are different. 



The genus of the Oak, or Quercus. is arranged 

 here, and takes its place in the natural order of the 

 Corylace.k. — The sterile flowers are arranged in a 

 loose ament or catkin, and have a calyx, which is 

 mostly 5-cleft, but no corolla ; the stamina are from 

 5 to 10 ; the fertile flower consists of a cup-shaped 

 scaly involucrum ; the calyx is incorporated with the 

 germ, and G-lobed ; tha germ 3-celled, with 2 of the 

 cells abortive ; the style single, but with 3 to 5 stig- 

 mas ; the nut (or acorn) coriaceous, 1-celled, and 

 1 -seeded, surrounded at the base by the enlarged 

 cup-shaped involucrum. In the United States there 

 are about 30 species, some of them evergreens, but the 

 most part deciduous leaved ; some of them have annual 

 and others biennial fructification, or have the acorns 

 produced in one or two different seasons. The cork 

 is the spongy bark of the Q. suber ; and from the Q. 

 coccifera is obtained those excrescences which afford 

 the galls of commerce. The Quercitron, so important 

 and common a yellow dye, is produced by the bark 

 of our Q. tinctoria, often improperly called Black 

 Oak. It is remarkable that in all the oaks known 

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