256 MANUAL OF BOTANT 



and surrounded by an involucre of bracts, which ultimately 

 form a cupule round the ovary and fruit ; ovary inferior, sur- 

 mounted by a rudimentary calyx, 3- or more-celled ; ovules 2 

 in each cell or solitary, pendulous or peltate ; stigmas almost 

 sessile. Fruit a glans or nut, 1-celled by abortion, more or less 

 enclosed by the cupule. Seeds large, 1 or 2, exalbuminous ; 

 cotyledons thick, fleshy or farinaceous ; radicle superior. 



Bentham and Hooker include the order Betulacese in the 

 Cupuliferae, and divide the order as thus constituted into three 

 tribes as follows : — Tribe 1. Betuleae. Tribe 2. Corylese. Tribe 

 3. Quercineae. 



The Betulese are at once distinguished by their superior 

 ovary and the absence of a cupule from the two latter ; and the 

 Corylese from the Quercineae by the male flowers being aohla- 

 mydeous, and having one ovule in each cell of the ovary ; the 

 latter having a 8 — 7-lobed ovary, and 2 ovules in each cell. 



Some authors, again, divide this order into two orders — 

 CorylacesB and Cupuliferse. 



Distribution and Numbers. — They abound in the forests of 

 temperate regions, A few occur in the high lands of tropical 

 and hot climates. Illustrative Genera : — Carpinus, Tourn. ; 

 Corylus, Tourn. \ Quercus, Tourn. There are nearly 300 

 species. 



Properties and Uses. — Most important on account of their 

 valuable timber. Many yield edible seeds, and some have 

 highly astringent barks and cupules. 



Order 42. BETULACBiE, the Birch Order. — Character. — 

 Trees or shrubs. Leaves simple, alternate, with deciduous 

 stipules. Flowers small, unisexual, monoecious, amentaceous, 

 with no true calyx, but in its place small scaly bracts, which in 

 some cases are arranged in a whorled manner. Male flowers 

 with 2 or 3 stamens opposite the bracts. Female flowers with a 

 2-celled ovary, and 1 pendulous anatropous ovule in each cell. 

 Fruit dry, thin, indehiscent, often winged, 1 — 2-celled, 1-seeded, 

 without a cupule. Seed pendulous, exalbuminous ; embryo 

 straight ; radicle superior^ Bentham a/nd Hoolcer include this 

 order in CupulifercE as the tribe Betulece. 



Distribution and Numbers. — They are principally natives of 

 the colder regions in the northern hemisphere. Illustrative 

 Oenera : — Betula, Linn.; Alnus, Tourn. These are the only 

 genera ; there are about 70 species. 



Properties and Uses. — They are valuable for their timber, 

 and for their astringent, tonic, and febrifugal barks. 



