THE BRASSICACE.E OF OHIO. 



Emma E. Laughlix. 



Brassicaceae. Mustard Family. 



Herbs, with watery sap of a pungent taste, not poisonous; 

 with alternate, exstipulate leaves, usually large at the base of 

 the stem and intergrading in form to the top of the stem. 

 Flowers hypogynous, bisporangiate, usually isobilateral, appear- 

 ing actinomorphic, regular, usually with glands, in racemes, short 

 at first and elongating, or in corymbs; calyx of 4 sepals, decidu- 

 ous, rarely persistent; corolla choripetalous, tetramerous, cruci- 

 form; stamens G, tetradynamous, rarely 4 or 2; ovulary com- 

 pound, bilocular, the parietal placentae connected by a thin 

 septum from which the valves separate when ripe; ovules 2 

 to several, campylotropous ; fruit a silique if longer than broad, 

 or a silicic if short, generally with 2 cavities, sometimes uni- 

 locular, dehiscent or in a few genera indehiscent; endosperm 

 scanty; cotyledons accumbent, incumbent or conduplicate. 



SYNOPSIS. 



I. Pod usually not more than twice as long as wide (a silicle); cotyledons accum- 

 bent or incumbent. 



A. Pods more or less flattened parallel to the broad partition, dehiscent; 

 cotyledons accumbent; leaves not lobed. 



1. Pubescence stellate or of forked hairs. 



Alysse.c 



Berteroa, Koniga, Alyssum, Draba. 



2. Pubescence of simple hairs or wanting; pods very broad and flat; 

 leaves opposite. 



LUNARIE.^. 



Lunaria. 



B. Pods flattened at right angles to the partition or not flattened. 



1. Pubescence of forked hairs; cotyledons incumbent. 



Cameline.^l. 



Camelina, Bursa, Neslia. 



2. Pubescence of simple hairs or wanting. 



a. Pod scarcely or not at all flattened; cotyledons accumbent. 



COCHLEARIE^. 



Armoracia, Neobeckia, Sisymbrium, Radicula. 



b. Pods strongly flattened at right angles to the narrow partition. 



(a) Pod dehiscent; cotyledons accumbent or incumbent. 



I^EPIDIEiE. 



Lepidium, Carara. Thlaspi. 



(b) Pod indehiscent; cotyledons incumbent. 



ISATIDE/E. 



Myagrum . 



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