50 FOUNDATIONS OF BOTANY 



flowers solitary or in small clusters. Calyx 3-5-lobed, minute 

 petals sometimes j^resent. Ovary 1-celled or incompletely 

 2^-celled. Fruit with a dry husk enclosing a bony nut.* 



I. JUGLANS, L. 



Staminate catkins cylindrical, solitary, borne on wood of 

 the previous year, stamens numerous, filaments short, calyx 

 4_(3.parted. Pistillate flowers single or a few together on a 

 short peduncle at the base of the growth of the season. Calyx 

 4-parted. Petals 4, minute, adnate to the ovary. Styles 2, 

 short, plumose. Fruit large, roundish or oval, husk fibrous- 

 fleshy, becoming dry, indehiscent, nut bony, very rough.* 



1. J. nigra, L. Black Walnut. Leaflets 1^-21, ovate-lanceo- 

 late, serrate, taper-pointed, somewhat cordate or oblique at the base, 

 nearly smooth above, downy beneath, petioles minutely downy. 

 Fruit usually single, roundish, about 2 in. in diameter. On rich 

 soil, rare near the coast. One of the most valuable of our native 

 trees, the wood being very durable and highly prized for cabinet 

 work.* 



2. J. cinerea, L. Butternut. Leaflets 15-19, ovate-lanceolate, 

 taper-pointed at the apex, rounded or slightly unsymmetrical at the 

 base, serrate, downy beneath ; petioles, branchlets, and fruit clothed 

 with short, sticky hairs. Fruit often somewhat in clusters, oblong, 

 large. More common northward. Wood less valuable and nut less 

 oily than the black walnut. The English walnut (/. regki) is 

 occasionally seen in cultivation. It has 7-11 leaflets and a nearly 

 smooth nut.* 



n. CARYA, Nutt. 



Leaflets serrate ; staminate catkins usually in threes on a 

 common peduncle, or sometimes sessile at the base of the 

 growth of the season ; calyx 2-3-parted, stamens 3-10, fila- 

 ments short. Pistillate flowers 2-5 in terminal clusters, 

 calyx 4-parted, petals none, styles 2 or 4, fringed. Fruit 

 somewhat globular, husk separating more or less completely 

 into 4 valves. Nut smooth or angled.* 



1. C. olivaeformis, Nutt. Pecan. A large tree with rough grav 

 bark, young twi^s and leaves downy, nearly smooth when mature. 

 Leaflets 11-15, oblong-lanceolate, acuminate, serrate, scythe-shaped. 

 Staminate catkins nearly sessile, 5-6 in. long. Husk thin nut oval 



