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1, Quercus L- OAK. 



Monoecious. Aments slender. $ perigo- 

 nium 4-8-parted; ? , 6-dentate; style short; 

 stigmas 3. Ovary 3-cellecl, 6-ovulate, surround- 

 ed by a scaly, budlike involucre, which in fruit 

 enlarges into a cup. ^ . 



1. 2. LOBATA Nee. 3 : aments pendulous; 

 abortive ovules at the base of the developed 

 seed; acorns maturing the first year; leaves 

 deciduous; branchlets glabrous; nut conical. 

 Common. Spring. 



"White oak." "Boble." Large, stately 

 tree. 



2. Q. DOTJGLASII Hook. & Arn. $ : aments 

 pendulous; abortive ovules at the base of the 

 developed seed; acorns maturing the first year; 

 leaves deciduous; branchlets pubescent; nut 

 oblong. Niles. Sonoma. 



"Blue oak." 



3. Q. DUMOSA Nutt. $ : aments pendulous; 

 abortive ovules at the base of the developed 

 seed; acorns maturing the first year; leaves 

 persistent, coriaceous; nut oval. Tamalpais. 



4. Q. CHBYSOLEPIS Liebm. 6 : aments pen- 

 dulous; abortive ovules scattered over the sur- 

 face of the developed seed; acorns biennial; 

 leaves persistent, coriaceous; nut obtuse. 

 Marin County. Spring. 



Tall tree, frequently called live oak. 



