NYCTAGIKACEJJJ. 11 



the globe. 1 Their bark is spongy ; their branches often thorny. 

 Their leaves are alternate or opposite, simple, entire, glabrous 

 and exstipulate. Their flowers are in simple or ramified racemes, 

 generally composed of cymes, sometimes umbelliferous or corymbi- 

 ferous, terminal, lateral, or inserted upon the wood of the stem 

 or branches. Each flower is accompanied at its base by small 

 bracts, generally two or three, more rarely from four to six, in 

 number. 



In Colignonia- the inferior part of the perianth forms an ovoidal 

 purse, enveloping the ovary with a narrow opening, beyond which 

 it dilates into a bell-shaped limb, with three or five valvate lobes. 

 The androceum is formed of five or six hypogynous stamens, more 

 or less exserted ; and the gynaeceum, inserted quite at the bottom of 

 the flower, has a glabrous uniovular ovary surmounted by a style, 

 stigmatiferous and capitate papillose, or penicillate at the apex. 

 The fruit is an acbene enveloped by the entirely persistent perianth. 

 Its inferior portion is dilated into a kind of sac, with three or four 

 vertical wings. The three or four species 3 of this genus are her- 

 baceous or suffrutescent plants, with very small and very numerous' 

 flowers, disposed in simple or ramified racemes of C} T mes, often 

 umbelliferous, sometimes accompanied by bracts or modified petaloid 

 leaves. They inhabit all western tropical America. 



Boldoa 4, has a tubular perianth, analogous to that of certain 

 Pisonias, and separated above into four valvate or induplicate teeth. 

 At the bottom is found a gynseceurn, surmounted by a long subulate 

 style, and three or four hypogynous exserted stamens. Three or 

 four species have been described, of which the best known is 

 Mexican. 5 The others are from the neighbouring regions, herbaceous 



1 L., Spec, 1511.— Sw., Prodr., 60; Fl. 3 H. B. K., Nov. Gen. et Spec, ii. 216, 

 lad. Occ, 643, I960.— H. B. K., Nov. Gen. t. 128 (Abronia). — Speeng., Sijst., i. 536 

 et Spec, ii. 217. — R. Be., Prodr. Fl. Nov.- (Tricralus). — Benth., PI. Hartweg., 148, n. 

 Holl., 422.— Endl., Prodr. Fl. Norfolk, 43. 628. 



— Bh.,Bijdr , 735.— Guillem., Zeph. Tail. 39. 4 Cav., Cat. Sort. Matrit. (1803), t. 7 



— Deless., Ic. Sel., iii. 51, t. 87. — Pcepp. et (nee J.). — Lagasc, Dlagn., 10. — Chois., Prodr., 



Endl., Nov. Gen. et Spec, 45, t. 161, 162 438. — Salpianthus H. B., PI. Mquin., i. (1805), 



(Need). — Casae., Bee. PI. Bras., viii. 69.— 155. — Endl., Gen., n. 2010. 



Link, Kl. et Ott., PI. Sort. Berol., 37, t. 15.— 5 Spbeng., Syst., i. 179.— H. B. K., Nov. 



Link, Enum., i. 354. —Benth., PL Harhveg „\\, Gen. et Spec, ii. 218. — Poie., Bict., Suppl. 



381. — Netto, in Ann. Sc. Nat., ser. 5, v. 80, v. 23 ; III., Suppl., cent. 10, ic. — Mart, et Gal., 



t. 7, 8.— Walp., Ann., i. 561 ; iii. 298 ; v. 722. in Bull. Acad. Brux., x. n. 4, 16. — Benth., 



2 Endl., Gen., n. 2001. — Chois., Prodr., 439, Voy. Sulph., Bot., 155. 

 n. 11. 



