Fox is one of many seedlings originated by B. S. Fox,[29] San José, California. Most of these seedlings were raised from seed of Belle Lucrative and Fox is among this number. The exact date of origin cannot be determined, but it is assumed to have been in the early seventies. The variety is considered to be one of the best of Fox's seedlings. Tree medium in size and vigor, upright-spreading, round-topped, moderately productive; trunk slender; branches stocky, smooth, greenish-brown overspread with grayish scarf-skin; branchlets thick, short, with short internodes, zigzag, glabrous, sprinkled with small, raised lenticels. Leaf-buds long, obtuse, pointed, free. Leaves 2-1/8 in. long, 1-1/4 in. wide, thick; apex abruptly pointed; margin nearly entire to finely serrate. Flower-buds conical, pointed, free; flowers open early. Fruit ripens October to November; large, 3-1/8 in. long, 2-1/8 in. wide, oblong-obovate-pyriform; stem 1-1/2 in. long, very thick, curved, obliquely set; cavity very shallow or lacking, the flesh folded up around the base of the stem; calyx closed or slightly open, variable in size; lobes much separated at the base, short, broad, acute; basin shallow, narrow, very small, furrowed and compressed; skin thick, granular, tough, roughened by the russet dots; color russet-yellow, often with a russet-red blush on the side next to the sun, almost entirely overspread with russet; dots numerous, conspicuous, russet; flesh white, granular near the core, melting, very juicy, sweet mingled with a brisk, vinous flavor, richly aromatic; quality very good. Core large, closed; calyx-tube short, wide; seeds wide, plump, acute. [Illustration: FREDERICK CLAPP] FREDERICK CLAPP =1.= Downing _Fr. Trees Am._ 2nd App. 148, fig. 1876. =2.= _Mass. Hort. Soc. Rpt._ Pt. II, 94. 1876. =3.= _Am. Pom. Soc. Cat._ 34. 1877. =4.= Budd-Hansen _Am. Hort. Man._ =2=:245. 1903. _Clapp No. 22._ =5.= _Mass. Hort. Soc. Rpt._ 90. 1872. =6.= _Ibid._ Pt. II, 153. 1874. =7.= _Am. Pom. Soc. Rpt._ 38, 66, 119. 1875. Frederick Clapp has a place on the pear list, because it is one of the few good varieties with acidulous fruits. The refreshing, piquant flavor, the tender, melting, very juicy flesh, and the bright lemon-yellow color with only a trace of red give sufficient charm and character to the fruits to make the variety desirable in every collection of good pears. The fruits come in season with those of Beurré Superfin, and surpass them in quality at least. The trees are vigorous and healthy and form open, shapely, wide-spreading heads that commend them for orchard management. They grow with rapidity and vigor, come in bearing early, and are unusually fruitful. The variety is seldom planted in commercial orchards, but it has a welcome place in every home orchard fortunate enough to have it.