50 CRUCIFERiE. 



the persistent placentae (rarely indehiscent). Seeds without albumen ; embryo 

 with the cotyledons folded on the radicle. — Herbs, or very rarely (never in 

 North America) somewhat shrubby plants, with a pungent or acrid watery 

 juice. Leaves alternate, often divided, without stipules. Flowers in racemes 

 or corymbs, mostly without bracts to the pedicels. 



CONSPECTUS OF THE TRIBES. 



1. SlLIQCOS«. 



Tribe I. Arabide^. Silique usually elongated (except sumctimcs in Naitvrlium), dehiscent; the valves somewhat 

 plane : dissepiment linear. Cotyledons plane, accumbcnt (i. e. the radicle is applied to their edges, 0^)i 

 parallel with the septum (i. c. with their edges applied to the placenUe). 



Tribe 11. SisYMBBEa:. Silique longitudinally dehiscent; valves nearly plane or somewhat terete and carinatc : septum 

 Uncar. Cotyledons plane, incumbent (i. e. with the radicle rpplied to the back of one of the cotyledons, 

 H 0)i contrary to (i. e. with the edges towards) the septum. Seeds not bordered. 



Tribe III, BRiSsicEi:. Silique dehiscent; septum linear. Style often enlarged, with a seminiferous cell at the base. 

 Seeds globose. Cotyledons incumbent, conduplicatc or longitudinally plicate, with the radicle lying in the 

 sinus (0>>)- 



2. SlLICCLOS^E. 



Tribe IV. Altssinej!. Silicic dehiscent; valves plane or convex : septum broadly oval and membranaceous. Seeds 



compressed, often marj;ined. Cotyledons plane, accumbent, parallel to the septum. 

 Tiibe V. CiMELiNEa:. Silicic dehiscent, ovoid or oblong, compressed parallel to the septum, or turgid ; valves plane 



or convex : septum elliptical or ovale, sometimes incomplete or none. Cotyledons plane, incumbent^ 



contrary to (i. e. their margin looking towards) the dissepiments. 

 Tribe VI. Thlaspide^. Silicle dehiscent, compressed contrary to the very narrow septum: valves boat-shaped. 



Cotyledons plane, accumbent, contrary to the septum. 

 Tribe VII. Lepidines. Silicle usually dehiscent, compressed contrary to the narrow septum (sometimes l-ccUed) ; 



valves boat-shaped, or rarely ventricose. Cotyledons plane, incumbent, parallel to the septum. 



3. LOMENTACE^. 



Tribe VIII. CiKiLiNEa:. Silique or silicle separating transversely into several 1-celled, 1-secded joints. Seeds usually 



compressed, not margined. Cotyledons plane, accumbent. 

 Tribe IX. RAPHiNEj:. Silique or silicle indehiscent, transversely separating into one- (or few-) seeded joints. Seeds 



globose. Cotyledons conduplicatc (as in Brassicacea). 



1. siuauos^ 



Tribe L ARABIDEJS. DC. 

 Silique usually elongated ; the valves somewhat plane ; dissepiment linear. Cotyledons 

 plane, accumbent {i. e. the radicle applied to their edges, o = ), parallel with the septum 

 (t. e. with their edges applied to the placentae). 



CONSPECTUS OF THE GENERA. 



1. Nastcrtium. Silique nearly terete, somethnes short ; valves neither nerved nor keeled. Sepals spreading. Seeds 



irregularly disposed in a double series. 



2. Babbabea. Silique 4-angled and somewhat 2-edged : valves nerved or keeled. Seeds in a single row. 



3. TcRRiTls. Silique linear, 2-edged: valves nerved or keeled. Seeds in a double row. 



4. AraBis. Silique linear, flattish : valves one-nerved in the middle. Seeds in a single row. 



5. Cardamine. Silique linear : valves flat, generally separating clastically, without nerves. Funiculus slender. 



6. Dentaria. Silique narrowly lanceolate, tapering : valves flat, generally separating clastically, nerveless. Funicnlua 



broad. 



