144 FOUNDATIONS OF BOTANY 



I. BERCHEMIA, Necker. 



Shrubs ; stems twining or erect. Leaves alternate, promi- 

 nently pinnate-veined, stipules minute. Flowers in axillary 

 or terminal panicles, or rarely solitary. Calyx-tube hemi- 

 spherical, 5-lobed. Petals 5, sessile, concave, as long as the 

 calyx. Ovary 2-celled, half-inferior ; stigmas 2. Fruit an 

 oval, 2-seeded stone-fruit.* 



1. B. volubilis, DC. SUPPLE-JACK, RATTAN-VINE. Woody, often 

 twining high ; older bark yellowish, twigs purple, wood very tough. 

 Leaves ovate or oval, acute or obtuse, cuspidate at the apex, 

 rounded at the base, wavy on the margins, green above, pale beneath. 

 Flowers in small panicles. Fruit purple. In moist woods and along 

 streams S.* 



H. RHAMNUS, L. 



Leaves alternate, deciduous. Flowers in small, axillary 

 cymes, often imperfect. Petals 4-5 or wanting. Stamens 4 

 or 5, very short. Stone-fruit, 2-4-seeded. 



1. R. lanceolata, Pursh. A tall shrub. Leaves with short peti- 

 oles, taper-pointed or somewhat obtuse, very variable in size, smooth 

 or nearly so above, more or less downy beneath, finely serrate. 

 Flowers 2 or 3 together in the axils, greenish, about in. in diame- 

 ter, usually dioecious, appearing at the same time as the leaves. 

 Calyx 4-lobed. Petals 4. Stamens 4. Fruit black, about in. in 

 diameter. Hills and river banks. 



2. R. caroliniana, Walt. CAROLINA BUCKTHORN. A small tree 

 with black bark and very hard wood ; twigs finely downy. Leaves 

 alternate, prominently veined, elliptical to broadly oval, entire or 

 obscurely serrate, smooth or sometimes downy below ; petioles slen- 

 der, downy. Flowers in axillary, peduncled umbels ; petals minute. 

 Fruit globose, - in. in diameter, 3-seeded. Seeds smooth. On 

 river banks.* 



m. CEANOTHUS, L. 



Shrubs. Leaves alternate, petioled. Flowers perfect, in 

 terminal panicles or corymbs formed of little umbel-like clus- 

 ters. Calyx-tube top-shaped or hemispherical, with a 5-lobed 

 border. Petals 5, with hoods, on slender claws. Stamens 5, 

 filaments long and thread-like. Fruit dry, 3-lobed, splitting 

 when ripe into 3 carpels. 



