CUPULIFER^E. (OAK FAMILY.)' 333 



margined. — Bot. Calif, ii. 81. Ranges eastward with the species, bat extends 

 westward to the S. Sierra Nevada and Oregon. 



3. CORYLUS, Tonrn. HazeI-nut. 



Sterile flowers in drooping cylindrical catkins. — Shrubs with doubly- 

 toothed leaves, flowering in early spring : sterile catkins single or fascicled 

 from scaly buds of the axils of the preceding year, the fertile terminating 

 early leafy shoots. 



1. C. rostrata, Ait. Shrub 2 to 5 feet high: leaves ovate or ovate- 

 oblong, somewhat heart-shaped, pointed: involucre of united bracts, much 

 prolonged above the ovoid nut into a narrow tubular beak, densely bristly. — 

 From Colorado to Washington, thence northward and eastward to the 

 Alleghauies. 



4. QUE ROUS, L. Oak. 



Sterile flowers in naked catkins, Fertile flowers scattered or somewhat 

 clustered. — Flowers greenish or yellowish : sterile catkins single or often 

 several from the same lateral scaly b.ud : flowering in the spring and shed- 

 ding the nuts in the fall. — Our two species are " White Oaks," being annual- 

 fruited and having sweet kernels. 



1. Q. macrocarpa, Michx. Leaves obovate or oblong, lyrately-pin- 

 natifid or deeply sinuate-lobed, or nearly parted, downy or pale beneath ; the 

 lobes sparingly and obtusely toothed, or the smaller ones entire : cup deep, 

 conspicuously imbricated with hard and thick-pointed scales, the upper ones aumed, 

 so as usually to make a mossy fringed border : acorn half immersed in or entirely 

 enclosed by the cup. — Throughout the Atlantic States and coming within our 

 range at its northeastern limit. North of the Missouri River a low scrubby 

 form is found, which has been called var. depressa, Engelm., having also 

 smaller leaves and much smaller acorns than the species. 



2. Q. undulata, Torr. Leaves from lyrate to nearly entire, always 

 downy below : the sweet and edible acorns oval, oblong, or sometimes elon- 

 gated : the subhemispherical, sessile, short- or sometimes long-peduncled cup 

 varies from scaly to very knobby. — Ann. Lye. N. Y. ii. 248, t. 4 ; Engelm. 

 in Trans. St. Louis Acad. iii. 382, 392. An exceedingly variable species, 

 embracing, as now understood, all the Rocky Mountain forms. These forms 

 can be arranged in two groups as follows : — 



# Leaves larger, strongly lobed, darker green, and decidedly deciduous : calyx- 

 lobes narrower, ciliate: acorns often thicker and shorter. — From W. Texas 

 through Colorado to Utah and Arizona. 



Var. Gambelii, Engelm. The large leaf with broader emarginate or 

 even lobed divisions. — Q. Gambelii, Nutt. 



Var. Gunnisoni, Engelm. Lobes of the leaf narrow and entire. — Q. 

 alba, var. Gunnisoni, Torr. 



Var. breviloba, Engelm. Leaves sinuate or broad- and short-lobed. — 

 Q. obtusiloba, var. breviloba, Torr. 



Var. Jamesii, Engelm. Like var. Gunnisoni, but the smaller and more 

 rierid leaves with acute lobes. 



