690 ANALYSIS OF THE ORDERS IN MONOCHLAMYDEA. 
B. Leaves exstipulate. 
a. Flowers unisexual. 
Ovules very numerous : . Podostemacex 
Ovules solitary, or very few. 
Flowers naked. 
Ovary l-celled . : : ; : . Myricacez. 
’ Flowers in an involucre. 
Anther-valves recurved - . ; . Atherospermacex. 
Anther-valves slit. 
Embryo on the outside of the albumen . Monimiacee. 
Embryo enclosed in the albumen . Euphorbiacex. 
b. Flowers hermaphrodite. 
Embryo ina vitellus . . ‘ : . Piperacex. 
Embryo without a vitellus . : : - . Podostemacex. 
2, Monochlamvdeous Flowers. 
A. Ovary inferior, or partially so. 
a. Leaves stipulate. 
1. Flowers hermaphrodite ; . 4 . Aristolochiacex. 
2. Flowers unisexual : . ° ° . Corylacezx. 
b. Leaves exstipulate. 
1. Flowers hermaphrodite. 
Ovary 3—6 celled. Ovules numerous . - Aristolochiacex. 
Ovary 1-celled. Ovules definite. 
Ovules with a naked nucleus. Leaves opposite . Loranthacex. 
Ovules with a naked nucleus. Leaves alter- 
nate: . : : : : . : . Santalacee. 
Ovules with a coated nucleus . : . . Chenopodiacezx. 
2. Flowers unisexual. 
Amentaceous : : ; : - ; . Juglandacezx. 
B. Ovary superior. 
a. Leaves stipulate. 
1. Flowers hermaphrodite. 
a, Carpel solitary. 
Stipules ochreate : : : : . Polygonacex. 
Stipules distinct : : : : : . Petiveriacex. 
6. Carpels more than one, combined. 
Seeds exalbuminous. 
Calyx imbricate . 2 ‘ , ; . Ulmacee. 
Seeds albuminous. 
Styles or stigmas 2. Leaves not dotted . Ulmacezx. 
2. Flowers unisexual. 
a. Carpel solitary. 
Cells of anther perpendicular to the filament . Stilaginacex. 
Cells of anther parallel to the filament. 
Embryo straight. 
Sap watery. Stipules small. Seeds albu- 
buminous. ; : : ; . Urticacex. 
Sap milky. Stipules large. Seeds ex- 
albuminous . ‘ 5 . : . Artocarpacex. 
