CORYLACEAE 



349 



base, their branches % to 1 inch long; starninate catkins yellowish green, a 

 distinct purple spot on the ends of the bracts ; sepals 6 ; stamens 6 or 7. 



Subalpine in northern California, occurring on Trinity Summit ("W.L.J. no. 

 2110) and Mt. Shasta, at about 6,500 to 7,000 feet, thence ranging far 

 northward. 



Eefs. ALNUS VIRIDIS DeCandolle, Fl. Fr. vol. 3, p. 304 (1805). Var. SINUATA Eegel, Gatt. 

 Bet. und Alnus, p. 422 (1865). A. sinuata Bydberg, Bull. Torr. Club, vol. 24, p. 190 (1897). 



2. BETULA L. BIRCH. 



Staminate catkins 1 to 3 in a cluster, sessile or short-peduncled ; calyx 4 

 (or 2)-lobed; stamens 2, the filaments shortly forked at apex, each fork with 

 an anther-cell. Pistillate catkins solitary on the peduncle and erect, each scale 

 consisting of the bract and 2 bractlets united; scales falling away from the 

 axis when the fruit is mature. Nutlet seed-like, with a broad thin wing. 

 Chiefly far northern regions (no other tree reaches so far north as the Canoe 

 Birch which goes to 66 N. lat.) ; about 35 species. 



Leaves 1 to 2 inches long; lobes of bracts broad, usually parallel, acutish. .1. B. occidentalis. 

 Leaves % to 1 inch long; lobes of bracts narrow, divergent, obtusish 2. B. glandulosa. 



1. B. occidentalis Hook. WATER BIRCH. Slender tree 10 to 25 feet high, 

 with red-brown smooth bark and warty twigs; leaves round ovate, sharply 

 serrate, mostly acute at apex, almost or quite glabrous and 1 to 2 inches long ; 

 petioles 4 or 5 lines long; staminate catkins 2 to 2,y 2 inches long; pistillate 

 catkins l l / 2 inches long in fruit and 3 or 4 lines in diameter; nutlets 1 to 1% 

 lines broad. 



Sierra Nevada, east slope from near Walker Pass northward, common in the 

 canons west of Owens Lake (W.L.J. no. 905) ; noted on the west slope only on 

 Bubbs Creek (W.L.J. no. 807) and near Simpson's Meadow. Siskiyous south 

 to Grouse Creek, Humboldt Co., and north to British Columbia and east to 

 Montana. 



Forma inopina Jepson n. form. Tree 15 feet high ; young branches rather 

 densely hairy ; pistillate catkins 1 inch long and 2 lines in diameter in fruit. 

 (Arbor 15 ped. alta, ramis juvenilibus subdense pilosis ; amenta feminina 1 poll, 

 longa et in fructo 2 lin. in diametro). Forks of Salmon River to Cecilville, 

 western Siskiyou, W.L.J. no. 2083, July 19, 1902. 



Refs. BETULA OCCIDENTALIS Hooker, Fl. Bor. Am. vol. 2, p. 155 (1853) ; Winkler, Engler's 

 Pflanzenreich, vol. 4, pt. 61, p. 86 (1904). B. fontanalis Sargent, Bot. Gaz. vol. 31, p. 239 

 (1901). B. alba, forma occidentalis Fernald, Am. Jour. Sci. ser. 4, vol. 14, p. 173, t. 5, 

 f. 3 (1902). 



2. B. glandulosa Michx. SCRUB BIRCH. Shrub 1 to 4 feet high with 

 glandular-warty twigs; leaves roundish, serrate, y 2 to 1 inch long; pistillate 

 catkins 4 to 9 lines long; nutlet 1 line broad. 



High mountains of northern Sierra Nevada (Bridge Creek, Lassen Co.), 

 Warner Range (Modoc Co.), and northward to subarctic regions where it 

 covers vast tracts of country. 



Eef. BETULA GLANDULOSA Michaux, Fl. Bor. Am. vol. 2, p. 180 (1803), type loc. Lake 

 Mistasinnis, Labrador. 



CORYLACEAE. HAZEL FAMILY. 



Shrubs or bushes with alternate simple leaves. Staminate flowers in catkins 

 without perianth; stamens 4 (seemingly 8) with forked filaments, each fork 

 bearing one cell of an anther, the undivided portion of the filament cohering 

 more or less with the scale or obsolete. Pistillate flowers several in a scaly bud, 



