FAGACEAE. 121 



Fruiting bracts 4 mm. long, lobed at the apex; leaves shining above. 



3. B.lenta. 

 Fruiting, bracts 8 mm. long, lobed to about the middle; leaves dull 

 above. 4. B. lutea. 



1. Betula populifolia Ait. American White Birch, Gray Birch. M. p. 



328. Moist or dry soil. Spring. 



2. Betula nigra L. River or Bed Birch. M. p. 328. Banks of streams- 



Spring. 



3. Betula lenta L. Cherry, Blaotc or Sweet Birch. M. p. 328: Eich. 



woodlands. Spring. 



4. Betula lutea Michx. f. Yellow or Gray Birch. M. p. 329. Moist 



woodlands. Spring. 

 Lancaster— (P.). Lehigh— Lehigh Mountain (Kr.). Dauphin— (P.)- 



5. ALiNTJS Gaertn. Alder. 

 1. Alnus rugosa (Duroi) K. Koch. M. p. 330. Wet soil; Early spring. 



Family 2. FAGACEAE Drude. Beech Family. 



Staminate flowers capitate; nut sharply triangular. 1. Fagus. 



Staminate flowers in slender aments; nut rounded or plano-convex. 



Pistillate flowers 2-5 in each involucre; involucre becoming globose and 

 very prickly in fruit, enclosing the nuts. 2. Castanea. 



Pistillate flower 1 in each involucre ; involucre of numerous scales 

 forming a cup in fruit and subtending the acorn. 3. Qnercus. 



•1. FAGUS L. 

 1. Fagus Americana Sweet. Beech. M. p. 331. Bich soil. Spring. 



2. CASTANEA Adans. 



Leaves green both sides ; large trees. 1. C. dentata. 



Leaves densely white-tomentose beneath ; shrub or small tree. 2. C. pumila. 



1. Castanea dentata (Marsh.) Borkh. Chestnut. M. p. 331. Bich soil. 



Early summer. 



2. Castanea pumila (L.) Mill. ^Chinquapin. M. p. 332. Dry soil. Early 



summer. 



Chester— (P.). Lancaster— Opposite York Furnace (St.). Dauphin— 

 Steelton (Wn.). 



Gloucester— Clarksboro (C), near Mickleton (He.), Swedesboro (Li.), 

 Tomlin (Wn.),. Salem— Jericho (C), Penn Grove (Wa.). Mercer- 

 Trenton, White Horse, Mercerville (C). 



New Castle — Newark, J. Webb; Middletown, J. A. Hunter; St. 

 George's, Tatnall. Scarce. 



3. QUERCUS L. 



A. Heaves or their lobes bristle-tipped, deciduous; acorn maturing in autumn 



of second year. 



Leaves pinnatifid or pinnately lobed. 



Leaves green on both sides. 



Cup of the aeorh saucer-shaped, much broader than high. 



Cup 16-25 mm. broad, acorn ovoid; leaves dull. 1. Q. rubra. 

 Cup 8-16 mm. broad; leaves shining. 2. Q. palustris. 



