CRTJCIFERM. 239 



27. Christolea Cambess. 1 — Sepals suberect; lateral saccate at base. 

 Petals long-tapering at base. Stamens 6, free 4-dynarnous. Siliqua 

 linear-lanceolate, much flattened ; style very short ; apex entire 

 minutely capitate subconical stigmatiferous ; valves flat, 1 -ribbed ; 

 septum membranous ribless. Seeds co, 1-seriate compressed im- 

 marginate ; embryo rather fleshy ; cotyledons incumbent linear. — A 

 herb (perennial) pubescent-tomentose, or subglabrous ; branches 

 diffuse prostrate or ascending, leafy ; leaves alternate sessile, obovate 

 cuneate rather thick entire or large-toothed ; flowers 2 in lax ebracteate 

 racemes {Alpine Thibef). 



28. Greggia A. Gray. 4 — Sepals linear patulous, equal at base. 

 Petals narrowed-unguiculate at base. Stamens 6, toothless. 

 Disk external to androceum, continuous unequally lobed. Siliqua 

 linear, compressed across septum, hoary ; style slender erect ; apex 

 thickened, cordate-2 -lobed, stigmatose ; valves orbicular-conduplicate, 

 thinly 1-ribbed. Seeds co, 1-seriate subovate turgid immarginate ; 

 funicles free. — A low undershrub, hoary with short stellate down ; 

 branches diffuse ; leaves spathulate, repand-dentate or sinuate; flowers 5 

 in lax racemes ; pedicels slender, elongated when fruiting" {Texas, 

 New Mexico 1 ). 



29. Syrenia Andrz. 8 — Flowers nearly of Cheiranthus or Erysimum ; 

 lateral sepals saccate at base. Siliqua short or elongated, linear 

 straight rigid, sub-4-gonous or laterally compressed ; style elongated 

 subulate ; apex stigmatose, capitate or 2-lobed, 9 papillose internally ; 

 valves saccately carinate ; dorsal rib thick ; septum thin opaque or 

 rather thick, 1 -ribbed, sometimes excavated. 10 Seeds go, 1, 2 -seriate 

 oblong immarginate ; funicles setaceous. — Branching 2-ennial herbs ; 



1 In Jacquem. Toy. Bot., 17, t. 17. — Ettdl., allied to Synthlaspi and Lyrocarpa." (B. H., 



Gen., n. 4914. — Hook. F. & Thoms., in Journ. loc. cit.) 



Linn. Soc, v. 167. — B. H., Gen., 80, n. 58. 7 Spec. 1. G. camporum A. Geay, loc. cit. 



Yellow. Walp., Ann., iv. 208. 



3 Spec. 1. C. crassifolia Cambess., loc. cit. — 8 Ex Ledeb., Fl. Alt., i. 162. — Endl., Gen., 

 Walp., Eep., i. 172. n. 4918.— B. H., Gen., 80, n. 57. 



4 PI. Wright., i. 8, t. 1 (nee G^ETN., nee 9 Elongated lobes of Zerdana in S. cuspi- 

 Enoelm.). — B. H., Gen., 80, n. 56. data. S. comuta Gay takes its name from its 



5 White. subarcuate reflexed lobes, stigmatiferous within. 



6 " A genus with habit, &c, of Erysimum, )0 Form of siliqua rather variable in S. sili- 

 and siliqua of Syrenia, but probably more closely culosa. 



