326 OXXVI. SALICINEH (Skan). [Populus. 
in Notizbl. Kén. Bot. Gart. Berlin, ii. 217, in Sitzungsber. Preuss. 
Akad. Wiss. 1904, 369, and in Engl. Jahrb. xxxvi. 252; Aschers. in 
Ber. Deutsch. Bot. Gesellsch. xxvia. 360. 
Nile Land. British East Africa: along the Tana River, from 1500 ft. to 
sea-level, Battiscombe, 207! Korokoro, Thomas ; Witu, Thomas, 49! on the 
banks of the Athi and Tsavo Rivers, Hildebrandt, 2608 ! 
Orver CXXVIIl. CERATOPHYLLE.. 
(By 8S. A. San.) 
Flowers moneecious. Perianth thinly herbaceous or submem- 
branous, equal; segments 6-12, subvalvate, often toothed or lace- 
rated at the apex. Male: Stamens 10-20, crowded on a flat_ or 
convex torus ; filaments very short ; anthers linear-oblong, equalling 
the perianth ; cells 2, linear, parallel, adnate, dehiscing longitudinally ; 
connective produced beyond the cells into a thick coloured usually 
2- or 3-toothed appendage. Female: Ovary 1, sessile, dvoid, 1- 
celled ; style terminal, linear-subulate, persistent ; stigma unilateral ; 
ovule 1, pendulous, anatropous. Fruit 1-seeded, leathery, inde- 
hiscent, ovoid or ellipsoid, somewhat compressed, tipped with the 
hardened style, sometimes with 2-4 spreading or reflexed spines at the 
base, wingless or surrounded by a narrow or broad leathery toothed 
wing, smooth or tuberculate. Seed pendulous ; testa membranous; 
albumen 0; embryo straight, with oblong rather thick equal cotyle- 
dons ; radicle very short; plumule large, many-leaved.—Aquatic 
herbs with elongated leafy floating branches. Leaves verticillate, 
2-fid or dichotomously divided ; segments linear or filiform, some- 
what rigid, usually toothed. Flowers axillary, solitary, very small, 
sessile, the male and female alternating at the nodes, or male at the 
lower and female at the upper. 
Ceratophyllum, the only genus, includes 1 or 2, or, according to some 
authorities, about a dozen species, growing in fresh water in nearly all parts 
of the world. 
1. CERATOPHYLLUM, Linn. ; Benth. et Hook. f. Gen. Pl. iii. 415. 
Characters and distribution of the Order. 
1. C. demersum, Linn. Sp. Pl. ed. i. 992. A glabrous perennial 
herb, Stems much-branched, floating and submerged, 2-3 ft. o7 
