BETTJLACEAE. 



21 



CARPINUS. Hornbeam. 

 (Family Betulaceae). 



Rather round-topped and openly 

 branched trees with sinewy-fluted 

 trunks and smooth gray bark: 

 deciduous. Twigs slender, zig-zag, 

 terete: pith small, roundish or 5- 

 sided, continuous, pale. Buds sol- 

 itary or very rarely superposed, 

 ovoid, sessile, oblique, with a 

 dozen 4-ranked scarcely striated 

 scales, or developing into cone- 

 like catkin-initials, the end-bud 

 lacking. Leaf-scars alternate, 2- 

 ranked, raised, crescent-shaped, 

 somewhat small: bundle-traces 3: 

 stipule-scars subequal, elongated. 

 Winter-character references: 

 C. Betulus. Bosemann, 70; Fant, 

 16, f. 9; Schneider, f. 10, 162; 

 Ward, 1:118, f. 59, 178, f. 88-89; 

 Willkomm, 26, f. 29; Zuccarini, 3, 

 pi. 2. C. caroliniana. Blakeslee & 



Jarvis, 332, 412, pi.; Brendel, pi. 2; Otis, 82. An early paper 

 on abscission, in which Carpinus figures, is by Ohlert in the 

 journal Linnaea for 1837. 



1. Buds large (fully 10 mm. long), straw-colored. C. cordata. 

 Buds moderate (6-8 mm.): European. C. Betulus. 

 Buds small (scarcely 5 mm.). 2. 



2. Buds straw-colored. C. japonica. 

 Buds brownish. 3. 



3. Buds glabrous. C. Turczaninowii. 

 Buds somewhat silky. 4. 



4. Twigs villous. 



Twigs glabrescent. (Blue beech). 



C. duinensis. 

 (1). C. caroliniana. 



