174 Karl M. Wiegand and Arthur J. Eames 



33. BETULACEAE (Birch Family) 



a. Staminate flowers without a calyx, naked, 1 (or at least appearing to be 1) to 

 each bract ; pistillate flowers with a calyx ; nut not winged, with involucrate 

 bracts ; fruiting inflorescence various. 

 b. Staminate flowers with' two bractlets ; pistillate flowers clustered in a scaly 

 bud ; nut large, with a conspicuous villous involucre ; small shrubs. 



1. Corylus 

 b. Staminate flowers with no bractlets ; pistillate inflorescence raceme-like ; nut 

 small. 

 c. Staminate aments naked through the winter, mostly clustered ; nut inclosed 

 in the bladder-like bract; lowest large veins of the leaf usually forked; bark 

 brown, flaky; trunk and branches terete; small trees. 2. Ostrya 



c. Staminate aments covered by bud scales during the winter, usually solitary ; 

 nut subtended by a large open leafy bract; lowest large veins of the leaf not 

 forked; bark light blue-gray, close; trunk and branches fluted, sinewy; tall 

 shrubs or small trees. 3. Carpinus 



a. Staminate flowers with a calyx, 2-6 to each bract; pistillate flowers without 

 a calyx ; nut winged or wingless, without an involucre ; fruiting spikes cone- 

 like. 

 b. Pistillate spike solitary ; fruiting bracts deciduous with or soon after the nuts, 



thin, 3-lobed ; nuts with a thin wing; stamens 2, bifid. 4. Betula 



/>. Pistillate spikes racemose; fruiting bracts persistent, thick and wood}', not lobed ; 

 nuts wingless or with a coriaceous margin; stamens 4, not bifid. 5. Alnus 



1. Corylus (Tourn.) L. 



a. Sterile catkins distinctly peduncled, the scales spoon-shaped with a naked point 

 and the bractlets exposed; involucre of the fruit short, spreading, exposing the 

 top of the nut ; twigs, especially at tip, and petioles glandular-bristly. 



1. C. americana 

 a. Sterile catkins sessile or subsessile, the scales more arching with short-hairy points 



and the bractlets usually concealed ; involucre of the fruit fused into a long 

 tubular beak, much exceeding the nut ; twigs and petioles not glandular-bristly. 



2. C. cornuta 



1. C. americana Walt. Hazelnut. 



Dry or well-drained, gravelly or sandy, acid or neutral, soils; frequent. Mar. 

 20-Apr. 20. 



Chiefly in the Inlet Valley (D. !) ; hillside near Larch Meadow (D. !) ; near Coy 

 Glen (D.); Six Mile Creek ravine (D. in C. U. Herb.); Cascadilla Glen (D. !) ; 

 Fall Creek, near the rifle range and near the Warren woodlot ; absent in the 

 McLean region and in the richer soils of the northern part of the basin. 



N. E. to Sask., southw. to Fla. and Kans. ; common along the coast. 



Forms approaching var. missouriensis DC. occur at the Fall Creek rifle range and 

 on the Warren farm east of Forest Home. 



2. C. cornuta Marsh. (C. rostrata Ait. of Gray's Man., ed. 7, and of Cayuga Fl.) 



Beaked Hazelnut. 



More or less sterile acid or neutral soils, probably less sandy than the preceding ; 

 common. Mar. 20-Apr. 20. 



Most frecpient on the hills of the southern part of the basin (D. !) ; around the 

 ravines (D. !) ; along Cayuga Lake (£>.!). 



Que. to B. C., southw. to Del., Mich., Kans., and Oreg., and in the mts. to Ga. ; 

 less abundant along the coast. 



Marshall's name was four rears earlier than Aiton's ('. rostrata. 



