CXCVII. BETULACE^E. 677 



persistent. STAMENS inserted at the bottom of the perianth, equal and opposite to 

 its lobes, rarely more numerous ; filaments filiform, distinct ; anthers 2-celled, 

 dorsifixed ; cells somewhat oblique, introrse, dehiscence longitudinal. OVAET free, 

 of 2 connate carpels, 2-celled (Ulmus) or 1-celled (Planera) ; styles 2, divergent, 

 stigmatiferous along their inner face ; ovules solitary in each cell, pendulous near 

 the top of the septum, or from the top of the single cell, anatropous. FRUIT a 

 membranous samara (Tllmus), or a coriaceous 1-celled and 1-seeded indehiscent 

 nut (Planera). SEED inverted, testa membranous, raphe longitudinal. EMBRYO 

 exalburninous, straight; cotyledons plane (Ulmus) or sub-sinuous (Planera), or con- 

 duplicate (Holoptelea) ; radicle short, superior. 



GENERA. 

 * Ulmus. * Planera. Holoptelea. 



By many botanists Ulmacece are united with Celticlece, from which they only differ in their inflores- 

 cence, extrorse anthers and anatropous ovule ; both are included in the class URTICINE^; of Brongniart 

 and adopted by Planchon ; for in Ulmacea;, though the ovule is anatropous, the micropyle faces the top of 

 the ovary, as in the other families of Urticinece. 



Ulmaceee are spread over the temperate northern regions [and sub-tropical India]. Their bark con- 

 tains an astringent and tonic bitter mucilage and tannin. The inner bark of the common Elm (Ulmus 

 campestris) has been considered a remedy for dropsy and eruptions. That of the American Elms ( U. 

 fulva and americana) is so rich in mucilage that poultices and a nutritious jelly are made of it. The 

 Americans reduce it to a powder as fine as flour, and employ it largely in inflammatory diseases. Planera 

 Abelicea, a native of Crete, produces an aromatic wood, formerly exported under the name of False 

 Saudalwood. Elm wood is rather hard, reddish, and used especially for wheelwright's work, shafts, 

 axle-trees, screws for presses, &c. Exostoses or wens are often developed on Elm trunks, which acquire 

 great hardness, and are much sought by cabinet-makers from the different patterns the twisted arrange- 

 ment of their wood-fibres exhibits. 



CXCVII. BETULACEJE. 



(AMENTACEARUM genera, Jussieu. BETULHSLE, L.-C. Richard. BETULACE^E, Bartling.) 



FLOWERS monoecious, in catkins, the $ with a calyciform scale-like perianth, the 

 $ achlamydeous, with accrescent scales. STAMENS 4 or 2. OVARY with two 2-ovuled 

 cells ; OVULES pendulous, anatropous. NUTS usually winged, 2-celled, \-seeded. EMBRYO 

 exalbuminous ; RADICLE superior. STEM woody. LEAVES alternate, stipulate. 



TREES or SHRUBS, branches scattered, buds scaly. LEAVES often sprinkled with 

 resinous glands, alternate, simple, toothed, the pinnate nerves terminating in the 

 teeth ; stipules free, caducous. FLOWERS monoecious, sessile, at the base of scaly 

 bracts, in terminal or lateral catkins. CATKINS $ : Scales bearing 2-3 flowers, 

 each accompanied within by 2 or 4 squamules. PERIANTH calyciform, regular, 

 4-lobed (Alnus), or reduced to a scale (Betula). STAMENS 4, inserted at the base of 

 the perianth-lobes, and opposite to them (Alnus) ; or 2, inserted at the base of the 

 scale-like perianth ; filaments bifurcate at the top (Betula) ; anthers basifixed, with 

 cells juxtaposed (Alnus), or separate on the branches of the filament (Betula), dehis- 

 cerice longitudinal. CATKINS ? sometimes pendulous, solitary, with membranous or 



