CL. XXI.] T3. SPARC ANIUM SIMPLEX. 437 



a shcatli, which is membranaceous on the sides ; the lowei- 

 leaves, when cut across, are trianguhir, with smooth interior 

 surfaces: the upper are somewhat concave, and do not exlii- 

 bit a triangular section. Besides, the leaves are almost all 

 longer than the stem, frequently tv/o feet high, and scarcely 

 the breadth of a little finger, uniformly small throughout, 

 smooth and entire, tapering at the point, and furnished with 

 parallel soft nerves. Their cellular texture is spongy and 

 compound ; the cells full of air. There are slits on both 

 sides of the leaves. In their centre rises a simple flower- 

 stalk, which carries below two petiolated spherical flower-tufts, 

 and above one stalkless female tuft, and several stalkless male 

 spherical flower tufts. The individual female florets consist 

 of three or four lanceolate scales or leaflets, in the centre of 

 which rises, on an oval germen, the simple, green, sometimes 

 cleft pistillum, having the stigma placed laterally at its sum- 

 mit. The male flowers contain, in the centre of the some- 

 what spoon-shaped scales, imperceptibly dentated at the top, 

 commonly three filaments of a white colour, on the top of 

 which stand the bilocular straw-yellow anthera\ containing 

 an oval pollen. The fruit is a brown nut, or drupa, contain- 

 ing in the centre of the albuminous matter, the uncvolved 

 -embryon in a reversed position. 



Diagnosis ami Affiuiti/. 

 The most nearly related species is Sp. ruiiiosnin. But 

 this species is much larger, its flower-stalk is branchy, the 

 sides of the leaves are concave, not smooth. The scales of the 

 calyx are also of a deeper brown colour. Sparg: vntans^ on 

 the other hand, has leaves entirely of a grass shape, swim- 

 ming on the surface of the water, rather concave, and very 

 long ; the flower-tuft is much smaller, and onlv the one that 

 is uppermost is male. This genus evidently borders on 

 Typha. I also find Chrysithrix related to it, the dividetl 

 shaft of which pushes out laterally the flower-tuft. Acorns 

 and Oroniium form the transition to (he Aroide-e, to whid) 

 these plants belong; (Anleit. ii. 1^7.) 



