ULMUS 



Ulmus, Linnaeus, Gen. PL 68 (1737) and Sp. PL 225 (1753); Lindley, in Rees, Cyclopcedia, xxxvii. 

 Nos. I to 13 (1818); Planchon, in De CandoUe, Prod. xvii. 154 (1873); Bentham et Hooker, 

 Gen. PL iii. 351 (1880); Schneider, Laubholzkunde, i. 212 (1904); Ascherson and Graebner, 

 Syn. Mitteleurop. Flora, iv. 546 (191 1). 



Microptelea, Spach, in Ann. Sc. Nat. xv. 358 (1841). 



ChcBtoptelea, Liebmann, in Vidensk. Medd. Kjobenh. 1850, p. 76. 



Deciduous or rarely sub-evergreen trees, with furrowed bark, and zigzag branchlets, 

 which are often provided with corky wings. Terminal leaf-buds not formed, the tip 

 of the branchlet dying and dropping off early in the season, leaving a small circular 

 scar close to the uppermost axillary bud, the latter in the following season prolonging 

 the branch. Buds composed of numerous ovate rounded scales, imbricated in two 

 ranks, those of the inner rows accrescent, and marking, when they fall, the base of 

 the branchlet with ring-like scars. 



Leaves simple, alternate, placed on the branchlet in two ranks, stalked, simply 

 or doubly serrate, penninerved, asymmetrical at the base,^ the inner half of the blade 

 being the larger. Stipules lateral, entire, free or connate at the base, usually early 

 deciduous. 



Flowers minute, perfect, appearing either in early spring before the leaves in the 

 axils of the leaf-scars of the previous year, or in autumn in the axils of the leaves of 

 the current year ; in stalked or sub-sessile fascicles or cymes ; articulated on slender 

 two-bracteolate pedicels : calyx, campanulate or funnel-shaped, with four to nine short 

 or deeply divided lobes : stamens three to eight, inserted under the ovary, with 

 thread-like filaments, and two-celled dorsifixed extrorse anthers, which dehisce by two 

 longitudinal openings ; ovary usually one-celled by abortion, sessile or stalked ; style 

 with two spreading lobes, stigmatic on the inner surface ; ovule solitary, suspended 

 from the apex of the cell. 



Fruit, a samara, ripening in two or three months after flowering, surrounded at 

 the base by the remains of the calyx, notched at the apex, the notch open or closed 

 by the incurved persistent stigmas and ciliate within ; seed-cavity in the centre or 

 above it, compressed, slightly thickened in margin, and produced into a thin 

 peripheral reticulate membranous wing. Seed solitary, suspended from the apex 

 of the cavity, without albumen ; cotyledons flat, raised above the ground in ger- 

 mination. 



> Cf. Van Tieghem in Ann, Set, Nat, (Sot.), iii. 377 (1906), on the peculiar asymmetry in the leaves and stipules of 

 the elm. 



1847 



