102 CRUCIFER.E. 



tudinal membranous or spongy dissepiment, less frequently unicellular or divided 

 transversely by spongy false partitions, thus becoming multicellular and indehis- 

 cent (^Raphanus) . Seeds uniseriate or biseriate ; cotyledons conduplicate. Petals 

 well developed. Pubescence, when present, usually hirsute. Hairs simple. 



* Fruit stout, iudehiscent, cuniiuonly more or less moiiiliforni, unicellular or transversely 

 divided by several false partitions. 



20. RAPHANUS. Sepals erect; the lateral somewhat saccate. Petals large, unguiculate, 

 white or pale yellow, less commonly pur])lish. Stamens 6, iinappendaged. Fruit attenuate 

 to a slender or rather stout beak. Seeds globular, pendulous. 



* * Fruit more slender, longitudinally 2-celled, and more or less completel}- dehiscent. 



21. BRASSICA. Sepals erect or spreading, glabrous, equal at the base or one pair some- 

 what saccate. Petals large, unguiculate, light yellow or white, often with purple markings. 

 Stamens 6, free and unappendaged. Pod terete or nearly so, tipped with a slender conical 

 or somewhat flattened empty or 1 -seeded often indehisceut beak. Seeds globose, uniseriate 

 or rarely and indistinctly biseriate in the cells. 



32. DIPLOTAXIS. Sepals erect or spreading, often pilose. Petals and stamens of the 

 preceding. Capsules slender, subterete or tingled, borne upon slender spreading pedicels ; 

 valves rather flat, 1 -nerved ; beak conical, sometimes very short. Seeds ovoid or oblong, 

 distinctly biseriate in the cells. 



Tribe VII. SISYMBRIE^E. Stigma when lobed elongated over the placentse (ex- 

 cept in Greggia). Fruit longitudinally 2-celled (very rarely 1-celled), from elliptic- 

 or lance-oblong to linear, always considerably longer than broad. Seeds numerous ; 

 cotyledons incumbent (very oblique or accumbent in some species of Erysimum). 

 A tribe of difficult limitation. 



* Hairs of stem simple, stellately branched or none, not regularly bifid. 



-)— Stigma entire, or with short lobes spreading over the placentae. 



++ Capsule 2-valved, terete, prismatic, or compressed parallel to the perfect or broad and 

 fenestrate septum. 



= Leaves elliptical, sessile and clasping by a cordate base : pods long, of firm texture, 

 angled : .stout glabrous annual with habit of a Brassica : introduced. 



23. CONRINGIA. Sepals and petals rather long and narrow. Valves of the capsule 

 1-3-nerved. Style short; stigma quite simple or more or less distinctly 2-lobed. Seeds 

 1-rowed in the cells, oblong, thick, not margined. Leaves entire. 



= = Leaves suborl)icnlar or reniform, broadly cordate, petiolate, toothed : pubescence 

 sim])le or none : pods elongated, angled : introduced biennial with foliage of a Cardamine 

 and fruit suggesting that of Barbareu. 



24. AL LI ARIA. Sepals oval, obtuse, caducous. Petals obovate. Stamens 6, free and 

 unappendaged. Pod many-seeded, often torulose ; valves keeled, more or less distinctly 

 3-nerved. Style short or none ; stigma simple. 



== = == Leaves various, not cordate, except in one or two species of Sisymbrium. 

 a. Septum of the capsule usually narrowly or broadly nerved, when nerveless having its 

 cells elongated longitudinally and usually ratlier thin-walled. 



25. EUTREMA. Sepals .short, ovate, rounded at apex, equal at base. I'etals exserted, 

 entire, obovate, short-clawed. Stamens 6, free and un.appendaged ; antliers short, ovate. 

 Style short or almost none; stigma small, simple. Fruit oblong-lanceolate to linear, some- 

 what flattened parallel to the septum, narrowed at each end ; valves 1-nerved and somewhat 

 keeled. Septum entire or very incomplete or almost wanting. Pubescence simple or none. 

 Leaves entire or nearly so. 



26. SMELOWSKIA. Sepals oblong, suliequal, soniewliat spreading. Petals entire, obo- 

 vate or spatulate, exserted. Stamens 6, unappendaged ; antliers olilong, slii;htly sagittate at 

 base. Pods lanceolate to lance-oblong, more or less obcompressed ; valves sharply keeled. 

 Stigma sessile. Leaves deeply pinnatifid. Hairs in part or all branched. 



