260 PRACTICAL BOTANY. 



834. Flowers all Avith three scarious bracts 835 



Flowers not 3-bracted. Herhs scurfy, sometimes 



silvery-meally 836 



835. Utricle opening transversely. (827) Amarantus. 

 Utricle indehiscent, or bursting irregularly. Sta- 

 mens and sepals 5, the latter half the length of the 5-ribbed, 

 thickish utricle. Herb prostrate. Leaves obovate, or rhom- 

 bic-ovate, cmarginate and petioled, often purple-veined. 

 Flowers in axillary clusters. 



(649) Euxolus pumilus, Raf. 



836. Fruit-bearing, broadly wedge-shaped bracts united. 

 Leaves oblong. Obione arenaria, Moq. (900). 



Fruit-bearing, ovate, or halberd-shaped bracts dis- 

 tinct or barely united at the base. Leaves triangular and 

 halberd-form, alternate, or partly opposite. Flowers in 

 spiked clusters. (826) Atriplex hastata, L. (893). 



837. (815.) Styles 3, each 3- to many-cleft. Ovary 3- 

 celled. Pod separating into 3 carpels 839 



Styles 2, feathery (sometimes partly united). Sta- 

 mens 6. Spikelets 1-flowered, the flower either staminate or 

 pistillate. Glumes wanting. Stout water-grasses, 6-10 feet 

 high. (567) Zizania. 



Style 1, long and filiform, or sessile stigmas 4. 

 Leaves whorled (or rarely scattered). Aquatic weeds. . .838 



838. Leaves pinnately parted into capillary divisions, 

 often whorled. Calyx of the sterile flowers 4-parted, of the 

 fertile 4-toothed. Petals caducous, or not developed. Sta- 

 mens 8 (or 4). Herbs partly submersed. 



(828) Myriophyllum. 



Leaves cut into thrice-forked, thread-like divisions. 



Staminate flower: stamens 12, or more, with large, oblong, 



sessile anthers. Pistillate flower: ovary ovoid, 1-ovuled ; 



style filiform. A submersed herb. 



Ceratophyllum demersum, L. 



839. Flowers cymose. Calyx 5-lobed, or parted, corolla- 

 like, white, in the staminate flowers salver-form. Stamens 

 10-15. Pod bristly-hairy. Herbs with stinging bristles. 



Cnidoscolus stimulosa, Gray. 



