EM PETR UM 
37i 
EUipantims Hook. f. Connaraceae. 4 sp. Indo-mal. 
Ellipeia Hook. f. et Thoms. Anonaceae (2). 8 sp. Malaya. 
Ellisia Linn. Hydrophyllaceae. 4 sp. N. Am. 
Elodea Michx. Hydrocharitaceae. 6 sp. Am., of which the chief is 
E . canadensis Michx., the American water-weed, which arrived in 
Brit, about 1842 and rapidly spread over almost all the inland waters 
of western Europe. Only the ? plant is known in Europe, and all the 
spreading is therefore due to vegetative multiplication chiefly by the 
breaking off of twigs. It is a submerged plant, slightly rooted, with 
whorls of leaves, in whose axils are found the squamulae usual in 
this group of plants. The <? flower has P 6, A 9 ; it breaks off as a 
bud and comes to the surface (cf. Vallisneria), where it opens. The 
ovary of the $ fir. grows to such a length as to bring the fir. to the 
surface, where it is pollinated. It has P 6, staminodes 3, G (3), and 
is enclosed below in a 2-leaved spathe. The plant is very hardy and 
does not form a true winter bud ; the leaves are merely a little more 
closely grouped together. 
Elsholtzia Willd. Labiatae (vi. 12). 20 sp. As., Eur., Abyss. 
Elymus Linn. Gramineae (xn). 50 sp. temp. E. arenarius L. the 
lyme grass, occurs on sand-dunes in Brit. (cf. Ammophila, and see 
p. 186) ; its leaves are coated with wax, but do not roll up in dry air. 
Elytraria Michx. ( Tubijiora Gmel.) Acanthaceae (1). 15 sp. trop. 
and sub-trop. 
Embelia Burm. f. Myrsinaceae (11). 60 sp. trop. 
Embothrium Forst. Proteaceae (11). 5 sp. Andes, Chili, E. Austr. 
Emex Neck. Polygonaceae (1. 2). 1 sp. Medit., S. Afr., Austr. The 
fruit is surrounded by the perianth, 3 of whose leaves are spiny. 
Emilia Cass. (incl. in Senecio Tourn. in Nat. PJi .). Compositae (vm). 
25 sp. trop., China, Madag. 
Emmenanthe Benth. Hydrophyllaceae. 10 sp. N.W. N. Am. 
Empetraceae. Dicotyledons (Archichl. Sapindales). 3 gen. with 4 sp., 
widely scattered over the N. Hemisph. and in the Andes. They 
occupy similar positions to the Ericaceae, and have a heath-like habit. 
The leaves are incurved backwards, forming a cavity on the under 
side, into which the stomata open, and which is partly filled up by 
hairs. The infl. is racemose and usually dioecious. In all but Corema 
the firs, are on ‘ short shoots ’ which arise laterally irom the main 
axis and bear only scales below the infl. K 3, C 3, A3, G(2 — 9). 
Loculi = cpls. ; ovules 1 in each, anatropous or nearly campylotropous, 
erect on axile placenta, with ventral raphe. Fruit a drupe with 2 — 9 
stones. Seed albuminous with no caruncle. The nearest related 
orders are Euphorbiaceae and Celastraceae or Buxaceae, but the 
family has been placed in various positions by different authors, e.g. 
by Benth. -Hooker (p. 136). Genera: Corema, Empetrum, Ceratiola. 
Empetrum (Tourn.) Linn. Empetraceae. The only sp., E. nigrum 
L., the crow-berry, is found on moors in the N. temp, zone (incl. 
