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1. Quercus L- Oak. 

 Monoecious. Aments slender. $ perigo- 

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

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

 ed by a scaly, budlike involucre, which in fruit 

 enlarges into a cup. — ^2 - 



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

 abortive ovules at the base of the developed 

 seed; acorns maturing tlie first year; leaves 

 deciduous; branchlets glabrous; nut conical. 

 Common. Spring. 



''White oak." "Koble." Large, stately 

 tree. 



2. Q. DouGLASii Hook. & Arn. S : 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. CHRYSOLEPis 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. 



