ORDER 38. ANACAKDIACE^. 283 



excessively pungent in taste. May. The cone-like warts on the bark of the 

 larger trees are very curious. 



4. PTELEA, L. SHRUB TREFOIL. (Gr. -rrre/lea, the elm tree ; from 

 the resemblance of tlie fruits.) ? $ $ . Sepals 3 to 6, mostly 4, much 

 shorter than the spreading petals ; $ stamens longer than the petals 

 and alternate with them, very short and imperfect in ? ; ovary of 2 

 united carpels ; styles united, short or ; stigmas 2 ; fruit 2-celled, 2- 

 seeded samarae, with a broad, orbicular margin. Shrubs with 3 to 5- 

 foliate Ivs. Fls. cymous. 



P. trifoliata L. Lvs. 3-foliate, Ifts. sessile, ovate, short-acuminate, lateral ones 

 inequilateral, terminal ones cuneate at base ; cymes corymbous ; stam. mostly 4 ; 

 sty. short. An ornamental shrub, 6 to 8f high, West. States, rare in "W. N. York. 

 Lfts. 3 to 4' by 1J to If, the ped. rather longer. Fls. white, odorous, nearly V 

 diain. Samara nearly 1' diam. 



5. AILANTUS, Desf. CHINESE " TREE-OF-HEAVEN." (From the 

 Chinese name, Ailanto.) ? $ Sepals 5, more or less united at base; 

 petals 5 ; $ stamens 2 to 3 ; ovaries 3 to 5 ; styles lateral; fruifol- 

 celled, 1 -seeded samarae, with oblong margins ; $ stamens 10 ; ? ova- 

 ries, styles and samara as in . Oriental trees and shrubs with pin- 

 nate Ivs. Fls. in panicles. 



A. glandulosa Desf. Lvs. glabrous, unequally pinnate, Ifts. ovate or oblong- 

 lanceolate, acuminate, shortly petiolate, with one or two obtuse, glandular teeth 

 each side at base, terminal one long-petiolate. A tree of large dimensions, and 

 with luxuriant foliage. Trunk straight, with a smooth, brown bark. Lvs. 3 to 

 5f in length, with 10 to 20 pairs of leaflets, and an odd one. Fls. in terminal 

 panicles, green, very ill-scented, rendering the tree a nuisance when in bloom 

 (May and June). The rapid growth of this tree is its only recommendation as a 

 tenant of our parks. 



ORDER XXXVIII. ANACARDIACEJ5. SUMACHS. 



Trees or shrubs, with a resinous, gummy, caustic, 

 or even milky juice. Leaves alternate, simple or 

 ternate, or unequally pinnate, without pellucid 

 dots. Fls. terminal or axillary, with bracts, com- 

 monly dioecious, small. Sepals 3 to 5, united at 

 base, persistent. Petals of tho same number, 

 (sometimes 0), imbricated. Stamens as many as 

 petals, alternate with them, distinct or coherent, 

 and perigynous. Ovary 1-celled, free. Ovule one. 

 Styles 3 or 0. Stigmas 3. Fruit a berry or drupe, 

 usually the latter, and 1 -seeded. Albumen 0. 



Genera 4S, species 100, chiefly natives of tropical 

 regions, represented in the V. ts". by the genus lihns 

 only. 



Propertle.fi. These plants abound in a resinous jnico, 



831 Rhus, leaf and panicle. :\ A Mam- which is poisonous, but is used as an indelible ink in 

 mate flower. 3. Section of a fertile flower, marking linen, and as an ingredient in varnish. Even 



the exhalations from some of the species are deemed 



poisonous. The Cashew nut is the product of a small tree of both Indies. When fresh the ker- 

 nel is full of a milky juice, and has a most delicious taste, but the coats arc filled with a caus- 

 tic oil which blisters the skin and kills warts. 



RHUS, L. SUMAC. (The ancient name, from Celtic, rhudd, red .?) 

 Calyx of 3 sepals united at base ; petals and stamens 5 ; styles 3, stig- 

 mas capitate ; fruit a small, 1-seeded, subglobous, dry drupe. Small 



