462 



ILLUSTRATIONS OF THE NATURAL ORDERS. 



Stipules sheathing. Nutlets club-shaped, in globular heads. 

 Stipules not sheathing or none. 

 Sterile flowers only amentaceous. 

 Fruit a kind of drupaceous nut. Leaves pinnate. 

 Fruit a dry nut, involucrate. Leaves simple. 

 Both kinds of flowers amentaceous. 

 Fruit a samara or a small dry drupe. 

 Ovary one-celled : ovule solitary, erect. 

 Ovary two-celled, two-ovuled : ovule pendulous. 

 Fnait a many-seeded follicle : seeds with a coma. 



Platanace.*:. 



JUGLANDACE^. 

 CUPULIPEK.*:. 



Myricace^. 



Betulace^e. 



Salicace^. 



890. Ord. AristolochiaCCBB {Blrthwort Family). Herbaceous or 

 climbing shrubby plants, with alternate leaves. Flowers brown 

 or greenish, usually solitary. Calyx-tube more or less united with 

 the ovary ; the limb valvate. Stamens six to twelve, epigynous, or 

 adherent to the base of the short and thick style : anthers adnate, 



1084 



1083 



1081 



1085 



1092 



extrorse. Ovary 3 - 6-celled. Capsule or berry three- to six-celled, 

 many-seeded. Embryo minute, in fleshy albumen. — Ex. Asarum 

 (Wild Ginger, Canada Snakeroot), Aristolochia (Virginia Snake- 

 root). Pungent, aromatic, or stimulant tonics ; generally termed 

 Snakeroots, being reputed antidotes for the bites of venomous snakes. 



FIG. 1081. Asarum Canadense. 1082. Cal3'x displayed, and a vertical section through the 

 rest of the flower. 1083. Cross-section of the ovary ; the upper portion (from which the limb 

 of the calyx is cut away) showing the stamens, the united styles, &c. 1084. A separate sta- 

 men, enlarged. 1085. Vertical section of a seed. 



