212 Eleventh Annual Report 



1. ULMUS. The Elms. 



Trees with deeply furrowed bark; leaves short petioled, with lat- 

 eral veins prominent and parallel, oblique or unequally heart- 

 shaped at the base, taper-pointed at the apex, mostly double-serrate; 

 flowers clustered or racemose, expanding before the leaves in March 

 or April; fruit a samara surrounded with a wide membranous mar- 

 gin, suborbicular to oblong, about 1-1.5 cm. (3^2 inch) long. 



Inner bark mucilaginous; leaves very rough above; flow- 

 ers nearly sessile, calyx lobes pubescent; fruit sub- 

 orbicular, not ciliate 2 U. fulva. 



Inner bark not mucilaginous; leaves smooth or somewhat 

 rough above; flowers on slender pedicels, calyx lobes 

 glabrous or pubescent only on the margins; fruit ovate 

 to oval, ciliate. 

 Branches without corky wings; faces of samara smooth. . 1 U. americana. 

 Branches (at least some of them) with corky wings; at 

 least one face of the samara pubescent. 

 Bud scales downy-ciliate, young branches pubescent; 

 calyx lobes 7-9, glabrous or nearly so; wing of 



samara as wide as the seed 3 U. Thomasi. 



Bud scales and branches almost glabrous; calyx 

 lobes 5, glabrous; wing of samara not as wide 

 as the seed 4 U. alata. 



1. Ulmus americana Linnseus. White Elm. Water Elm. 

 Swamp Elm. Gray Elm. Bitter Elm. Sour Elm. Red Elm 

 (frequently in the southwestern counties). Plate 61. Bark deep- 

 ly fissured, the ridges rather broad, ashy gray or darker, especially 

 in the swamps in the southwestern part of the State; twigs round, 

 glabrous or slightly pubescent; buds glabrous; leaves oval to obo- 

 vate-oblong, 5-12 cm. (2-5 inches) long, hairy both above and below 

 when they expand, becoming at maturity dark green, smooth, or 

 rough above, especially on vigorous shoots or on young trees, paler 

 and smooth or somewhat, pubescent beneath and yellow before fall- 

 ing; fruit on pedicels 1-3 cm. (^-1 inch) long, jointed near the middle, 

 ripening when the leaves begin to unfold. 



Distribution. Quebec to Florida, west to Nebraska and Texas. 

 Found in low ground in every county of the State. It is frequent 

 to very common along flood plains, in swamps, on borders of lakes 

 and on low ground generally. In our area it is usually a large tree, 

 attaining a height of 20-30 m. (65-100 feet) and a diameter of 16 

 dm. (48 inches). 



The published records of the distribution are as follows: Car- 

 roll (Thompson); Cass (Benedict and Elrod); Clark (Baird and 

 Taylor) and (Smith) ; Dearborn (Collins) ; Delaware (Phinney) ; Del- 

 aware, Jay, Randolph and Wayne (Phinney); Fountain (Brown); 



