178 XVII. POUTULACEiE, [Moiitia. 



upper leaves, tlie petals of a pare wlute, very little longer tliau the calyx. 

 Capsules small.— IJook. f. Fl. Tasiu. i. 144. 



Tasxaania. In springs on St. Patrick's Kivcr at an elevation of 1500 ft., abundantly, 

 Gunn. 



The species is common throuo;liout Europe, in Nortliern Asia aud N.W. America, and 

 thence down the Andes to Australia, America, and in New Zealand, but not in central or 

 tropical Asia, nor, as far as hitherto known, in any 2>^i't of Africa except Algeria. 



Order XVIII. ELATINEiE. 



Flowers regular, liermaiilirodite. Sepals 2 to 5, free, imbricate in the bud 

 Petals as piany, hypogynous, imbricate in the bud, occasionally wantmij. 

 Stamens as many or twice as many, hypogynous, free ; anthers 2-celled. Torus 

 small, without any disk. Ovary free, with as many cells as there are sepals; 

 styles as many, free from the base, with terminal capitate stigmas. Ovules 

 several in each cell, attached to the inner angle, anatropous. Capsule opening 

 septicidaUy, the valves flat or concave, with the margins inflexed, leaving more 

 or less of the dissepiments attached to the central column. Seeds straight or 

 curved, testa crustaceous, usually wrinkled or ribbed, albumen noue or very 

 tliin. Embryo filling the seed, cotyledons short, radicle next to the hiluin. 



Herbs or low undershrubs, atpiatic, creeping or diffuse. Leaves opposite 

 or rarely verticillate, entire or serrate. Stipules in pairs. Plowers small, 

 axillary, solitary or in clusters or cymes. 



A small Order dispersed over nearly the whole globe, allied to Ilf/pericineo! and CaryO" 

 phj/Uece, hut differing fi'om the former in liabit, in the stipules, and in the perfectly iso- 

 nxcrous flowers, from the latter chiefly in the ovary and fruit and want of albumen to the 

 seeds ; there is also considerable affinity, especinlly in habit, with Lj/ihrariea and Crasm- 

 lacem. The only two genera of the Order, both of them of wide geographical range, are 

 represented in Australia. 



Sej)als membranous, obtuse. Capsule membranous. Glabrous, aquatic or 



creeping herbs. Flowers 2- to 4-merous 1. Elatink. 



Sepals herbaceous in the middle or keeled, acute. Capsule almost crusta- 

 ceous. Herbs or undershrubs. Flowers usually 5-mcrous, rarely 3- io 

 4-merous 2. Bkugta. 



1. EliATINE, Linn. 



Mowers 3- or 4-merous, rarely 2-merous. Sepals membranous, obtuse, 

 not keeled. Ovary globular. Capsule membranous, the dissepiments either 

 disappearing or remaining attached to the central colunm. — Small glabrous 

 herbs, either aquatic or creeping on mud. Leaves opposite or verticillate. 

 Flowers usually solitary in the axils, and very small. 



The genus is widely di:,pcrscd over the temperate and subtropical regions of the globe. 

 The Australian species is considered by some as endemic, by others as identical with an 



American one. 



^ 1- E. americana, Jrn.in Edlnb. Jouni. NaL Sc. i. 431, var. aifslra- 

 liemis. A small, tender, glabrous annual, prostrate and creeping over nuul 

 in dense tufts, sometimes not 1 in. in diameter, sometimes extending over a 

 considerable surface. Leaves in the ordinary form ovate, obovate, or broadly 

 oblong, 2 to 3 lines long, thin and of a bright green; but in some luxuriant 



