RHAMNUS 145 



Leaf-scars alternate or sometimes nearly opposite, small, cres- 

 cent-shaped or half-elliptical; bundle-traces 3 or joined in a series; 

 stipule- scars minute. 



Although the common name. Buckthorn is applied to species 

 of this genus, many of them are not thorny. 



a. Buds scaly 



b. Twigs red or brown, glabrous 1. R. alnifolia 



b. Twigs gray, often downy 2.R. lanceolata 



a. Buds naked 3.R. caroliniana 



1. R. alnifolia L'Her. Alder-leaf Buckthorn. Low spreading 

 shrub, 1. 5-8 dm. high, with slender unarmed upright gray bran- 

 ches and smooth bark; twigs red or brown, glabrate; buds small, 

 under 5 mm. long; leaf-scars alternate. Swamps and meadows, 

 Newfoundland to British Columbia, south to West Virginia, Illinois, 

 Nebraska, Wyoming and California (Fig. 205). 



2. R, lanceolata Pursh. Lanceleaf Buckthorn . Erect shrub 

 up to 2 m. high, with slender unarmed branches and smooth gray- 

 ish bark; twigs reddish-brown, often downy; buds small, 5 mm. 

 or less long. Thickets, Alabama to Texas, north to Pennsylvania 

 and Nebraska (Fig. 206). 



3. R. caroliniana Walt. Carolina Buckthorn . Indian Cherry . 

 Shrub or small tree up to 11 m. high, without thorns; young branch- 

 lets puberulent; buds short, scarcely 5 mm. long; fruiting pedi- 

 cels several in a cluster. Rich woods, Florida to Texas, north to 

 Virginia, Missouri, and Nebraska (Fig. 207). 



CEANOTHUS L. (Rhamnaceae) 



Low deciduous shrubs. Twigs slender, rounded, puberulent; 

 pith large, white, continuous. Buds small, solitary, sessile, ovoid. 

 Leaf-scars alternate, half-elliptical, small; bundle-trace 1, trans- 

 verse, sometimes compound; stipules small, persistent, or leav- 

 ing narrow scars. The dry capsules and/or their bases are present 

 in winter, like miniature cups-and-saucers. 



1. C. americanus L. New Jersey Tea. Red-Root . Low un- 

 armed shrub about 1 m. high, with slender upright branches; roots 

 dark red; twigs slender, puberulent, green or brownish. Dry banks, 

 Quebec to Manitoba, south to Florida and Texas (Fig. 208). 



