THE ELM FAMILY 



ULMACEiE Mirbel 



LMS arc closely related botanically to about fourteen other genera of 

 trees and shrubs, including in all about 140 species, which are widely 

 distributed in temperate and tropical regions. These agree in having 

 alternate stalked simple pinnately veined leaves, usually toothed and 

 sometimes 3-nerved at the base; the stipules are fugacious, that is, they fall away 

 while the leaves are unfolding, and are hence liable to be overlooked. The flowers 

 are small and incomplete, having no corolla, and they are either perfect or imper- 

 fect. The calyx is from 3-parted to 9-parted, the divisions or sepals often separate 

 to the base. In the trees here described there are as many stamens as there are 

 divisions of the calyx, and they are opposite them; the anthers spht lengthwise 

 to discharge the pollen. The ovary is i-celled or very rarely 2-celled, superior; 

 there is i pendulous ovule; there are 2 styles or 2 sessile stigmas. The fruit 

 varies greatly in the several genera, being either a samara (Ulmus), a small nut 

 (Planera), or a drupe (Celtis and Trema). The seed has little endosperm or 

 none. They are of little value except for their timber and as shade trees. 

 Our genera may be distinguished by the following characters: 



Fruit dry, a samara or small nut. 



Fruit a samara, winged all around. 



Fruit a small nut, bearing soft tubercles. 

 Fruit fleshy, juicy; a drupe. 



Drupes stalked, solitary in the leaf-axils. 



Drupes cymosely clustered in the axils. 



1. Ulmus. 



2. Planera. 



3. Celtis. 



4. Trema. 



1. THE ELMS 



GENUS ULMUS [TOURNEFORT] LINN^US 



HE ancient Latin name of the elm was accepted by Linnaeus as the 

 botanical name of the genus. In America, besides the six species 

 here described, one occurs in southern Mexico and Central America, 

 and about ten others exist in Europe and Asia. Ulmus parvijolia 

 Jacquin, of China and Japan, is a shrub, but the other species are all trees. The 

 wood of the elms is hard and strong, and is of much importance commercially. 

 The trees are much planted for shade and ornament. 



The leaves are two-ranked, straight-veined, toothed, and usually very unequal- 



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