660 



Rhamnaceae 



Rhamnus 



50 



Map 1374 



Rhamnus lanceolata Pursh. 



Leaves mostly with 3 pairs of veins; flowers 4-parted; nutlets 3 or 4. (See excluded 



species no. 433, p. 1072.) R. cathartica. 



Leaves mostly with 4-10 pairs of veins; flowers 4- or 5-parted; nutlets 2 or 3. 



Flowers 4-parted; nutlets 2; leaves pubescent beneath 2. R. lanceolata. 



Flowers 5-parted; nutlets 3. 



Leaves crenate-serrulate ; petals none; nutlets grooved on the back; leaves glab- 

 rous or glabrate beneath 3. R. alni folia. 



Leaves entire or nearly so, glabrous beneath; petals 5; nutlets smooth on the 

 back 4. R. Frangula. 



1. Rhamnus caroliniana Walt. Carolina Buckthorn. Map 1373. On 

 rocky wooded slopes near the Ohio River and rarely inland on gentle 

 wooded slopes. 



Va. to Nebr., southw. to Fla. and Tex. 



la. Rhamnus caroliniana var. mollis Fern. (Rhodora 12: 79. 1910.) 

 This is a form with the under surface of the leaves more or less densely 

 pubescent. Specimens in our area show all grades of pubescence. 



2. Rhamnus lanceolata Pursh. Lance-leaf Buckthorn. Map 1374. 

 This species is very local and has two distinct habitats. One is on limestone 

 cliffs and rocky or gravelly wooded slopes and the other is in springy places 

 with skunk cabbage, and in alluvial soil along streams. 



Pa., Ind., and Nebr., southw. to Ala. and Tex. 



3. Rhamnus alnifolia L'Her. Alder Buckthorn. Map 1375. A small 

 shrub in or on the borders of tamarack bogs and at the moist bases of 

 dunes in the dune area. Rare. 



Newf. to B. C, southw. to N. J., W. Va., 111., and Calif. 



4. Rhamnus FrAngula L. Glossy Buckthorn. Freely escaping about 

 Interlaken in La Porte County. First reported by J. A. Nieuwland. In 

 1938 S. W. Witmer of Goshen College found a colony about 15 feet high 

 in low, mucky soil in sec. 34 about 2 miles north of Goshen, Elkhart County. 



Nat. of Eu. 



