CUPULIFER^. ([OAK FAMILY.) 331 



!. L. Canadensis, Gaudichaud. Leaves ovate, pointed, strongly feather 



veined, long petioled ; stipule single, 2-c'left. — Throughout the AtLiutic 

 States, aud coming within our borders at the north wc.-si. 



5. PARIETARIA, Tourn. I'kli.itort. 



The staminate, pistillate, and perfect flowers interniixod in tho Kinie invf>. 

 lucrate-bracted cymose axilhiry clu>ters. — Diffuse or tuftnl herbs, with eniiro 

 3-ribbed leaves and no stipules. 



1. P. Pennsylvanica, Mulil. Low, simple or sparingly branched, 

 minutely downy: leaves oblong-hmceolate, thin, veiny, roughish with opafpio 

 dots : flowers shorter than the leaves of the involucre. — From Coluradu to 

 Nevada and eastward across the continent. 



6. HUMULUS, L. Hop. 



Sterile flowers with 5 sepals and 5 erect stamens. Fertile flowers in .short 

 spikes with leafy imbricated bracts, each 2-flowered. Akene invested with the 

 enlarged scale-like calyx. — Twining rough perennials, with stems aImo.<;t 

 prickly downwards, mostly opposite heart-shaped aud palmately 3 to 7-lobed 

 leaves. 



I. H. Lupulus, L. Leaves commonly longer than the petioles: the 

 fruiting calyx, akene, etc., sprinkled with yellow resinous grains, giving the 

 bitterness and aroma of the hop. — In the mouutams from New Mexico to 

 British America and eastward across the contiueut. 



Order 74. CUPULIFER^. (Oak Family.) 



Trees or shrubs, with alternate aud simple straight- vciucd leaves, 

 deciduous stipules, and monoecious flowers, both kinds of flowers in 

 catkins, or the fertile solitary, clustered, or spiked, the 1 -celled, l-sfcded 

 nut with or without an involucre. 



Tribe I. Both kinds of flowers in scaly catkins, 2 or 3 under each bract, and no invohicre 

 to the naked often winpcd small nut. — BFrrt'LE.*- 



1. Betula. Stamens 2, with bifurrate tilainents and separat« anther-crlls. Bract-s S-lobc*!. 



becoining coriaceous aud caducous. Nutlet broadly wingrwL 



2. Alnus. Stamens 4: anther-cells contiguous. Bracts entirp, iKroniinR w<>ody, ]>er- 



sistent. Nutlet not winged. 



??ribe II. Sterile flowers destitute of a true calj-x, oonsistinR of several Ptamons inrlminl 

 uiKJer and more or less adnate to a bract: filaments sliort ; anthers l^elUsl. Fertile 

 flowers in a scaly bud or catkin, two under each fertile bract, each with one or nj«n- 

 bractlets, which form a foliaceous involucre to the nut — Corvle.« 



3. Corylus. Bract of staminate flower fumislied with a i>alr of bractlet* inside. Inv.v. 



lucre leafy-coriaceous, enclosing the large bony nut 



Tribe III. Sterile flowers with a distinct 4 to 7-lobed calyit, including » to 20 »t«men«: 

 filaments exserted ; anthers 2-celled. Fertile flowers one or few encl.wcd in a cu|.ul« 

 consisting of bracts variously consolidatetl. — QiTRriNi-.e. 



4. Quercus. Sterile flowers in slender catkins. CupiUc 1-flowered. »caly »x»d entire: 



nut hard aud terete. 



