ULMUS 613 
Placed (united to Sparganiaceae) in Nudiflorae by Benth. -Hooker, in 
Spadiciflorae by Warming. 
Typhonium Schott. Araceae (vn). 15 sp., E. Ind., Austr. 
Ugni Turcz. = Myrtus Tourn. 
Ulex Linn. Leguminosae (ill. 3). 20 sp. W. Eur., N. Afr. ; 3 in Brit., 
(J. enropaeus L ., U ’. nanus Forst., and U. Gallii Planch., the gorse, 
furze, or whin. These plants cover large areas of ground, especially 
on heaths (p. 185). The leaves are reduced in size, and many of the 
branches are reduced to green spines, so that the xerophytism is 
clearly marked. The firs, explode like those of Genista, and the fruit 
explodes by the twisting up of its valves in dry air. The seeds in 
germination show interesting transition-stages from the usual com- 
pound leaf seen in the order to the needle-leaf of the mature plant 
(p. 29, and cf. Acacia). 
Ullucus Caldas. Basellaceae. 1 sp. Andes, U. tuberosus Caldas. The 
lateral branches of the rhizome swell up into tubers like potatoes, and 
are used as food. 
Ulmaceae. Dicotyledons (Archichl. Urticales). 13 gen. with 130 sp., 
trop. and temp. Trees with sympodial stems, bearing 2-ranked 
simple often asymmetrical leaves with stipules. Firs, usually in cymose 
clusters, generally unisexual. P 4 — 5, free or united, sepaloid, theo- 
retically belonging to two whorls ; A 4 — 5, opp. the perianth-leaves, 
in two whorls ; G rudimentary in $ fir., in the ? of (2) cpls., sometimes 
2-loc. but usually i-loc., the second loc. aborting. Ovules 1 per loc., 
anatropous or amphitropous, pendulous. Style linear or bifid. Nut, 
samara or drupe. Seed usually with no endosperm. The wood of many 
Ulmaceae is useful. Chief genera : Ulmus, Celtis. United to Urtica- 
ceae by Benth.-Hooker, placed in Urticiflorae by Warming. 
Ulmaria (Tourn.) Hill. Rosaceae (in. 8). 8 or 9 herbaceous species of 
the N. Hemisphere are sometimes separated from Spiraea under this 
name. They possess 2 seeds in each cpl., 1 only maturing, the fruits 
being achenes, while most sp. of the genus Spiraea have slightly 
adherent follicles and are shrubby (cf. Rosaceae). Holodiscus discolor 
Maxim. (S. ariaefolia Pursh) links U. to Spiraea. U. palustris 
Moench is S. Ulmaria, and U. Filipendula Hill is S. Filipendula of 
British Floras. The former is the meadow-sweet. 
Ulmus (Tourn.) Linn. Ulmaceae. 16 sp. N. temp, and Mts. of trop. 
Asia. U. montana With, (wych elm) and U. campestris L. (elm) in Brit. 
The leaves are asymmetrical, one side being larger than the other (cf. 
Begonia). The firs, are $ and come out before the leaves as little 
reddish tufts. If one of these tufts be examined, it will be found to 
be a short axis with a number of leaves, beginning 2-ranked at the 
base and going over to 5-ranked above. There are 110 firs, in the 
axils of the lowest 10 or 12 ; in the axils of the upper leaves are firs, 
arranged in small dichasial cymes (cf. Betulaceae), which are reduced, 
in U campestris and others, to the one central fir. Each fir. has 
