414 
The Ohio Naturalist. 
[Vol. XII, No. 2, 
THALAMIFLORAE. 
Herbs or woody plants with hypogynous, choripetalous or 
apetalous flowers, calyx commonly of distinct sepals and inserted, 
with the other parts of the flower, directly on the floral axis. 
Synopsis. 
I. Carpels many to one, spiral or cyclic, usually free or only 
slightly united; stamens usually numerous. Ranales. 
II. Carpels more or less united, cyclic. 
1. Herbs with insectivorous leaves; carpels 5-3. Sarraceniales. 
2. Herbs or woody plants with normal leaves, not 
insectivorous. 
a. Carpels 2 or more with parietal placentae; perianth 
usually with an even number of segments, the 
flowers commonly isobilateral. Brassicales. 
b. Carpels mostly 5 or 3; stamens mostly 10 or 5, or a 
reduction from 10; ovules pendulous. Geraniales. 
c. Carpels many to 3, ovules few; stamens indefinite, 
monadelphous, branched or clustered, or by reduc- 
tion separate and few; sepals valvate. Malvales. 
d. Carpels 2 or more, commonly with parietal placentae; 
stamens usually indefinite; sepals and petals usually 
5, sepals imbricated or convolute. Guttiferales. 
CENTROSPERMAE. 
Mostly herbaceous plants with hypogynous syncarpous 
flowers; usually apetalous except in the lowest families; ovulary 
usually with a central basal ovule or with many ovules on a 
central placenta. 
Synopsis. 
I. Perianth present consisting of a calyx and corolla or of a 
calyx only. 
1. Embryo curved, coiled, or annular, fruit not an achene. 
a. Fruit a capsule, berry, or anthocarp; calyx present; 
corolla present or absent. Caryophyllales. 
b. Fruit a utricle; calyx present, corolla none. 
Chenopodiales. 
2. Embryo straight or nearly so; fruit an achene. Polygonales. 
II. Perianth none or vestigial; ovules usually orthotropous. 
Piperales. 
CALYCIFLORAE. 
Perianth and stamens usually borne on a perigynous disk or 
hypanthium which is sometimes united with the ovulary; carpels 
free or united; calyx usually of united sepals, petals when present 
separate. 
