66 



CRUCIFER^. [Eutrema. 



I&ta, obtnsa, inferne paululum atteiiUata, utrinque marginof[ne pilosa, pilis plerumque simplicibus. Scapi 

 ^urlmi ex eadem radice, vix diVitem longi, pubescentes, omnino aphylli. Fhres majusculi, albi, fran^ntes, 

 primum in corymbum compactiim dispositi, demum racemosi. PedicelU breves, vix calyce lougiorea. Sepdta 

 late ovata^ coticava, aequaliaj margine glabro, membranaceo, dorso pubescente. Petala caljce duplo longiora ; 

 ung;ue anfl^sto calyce breviore, lamina fere orbicular!, subretusa. Stamina calycem vix lon^tudine exce- 

 dentia. Anthera. breves, subrotundaa. Germen fere exacte ovale, dense pubescenti-pilosum, biloculare, 

 valvis valde couvexis, stylo subdimidio breviore terminatum. Stigma dilatatum, obscure bilobum. Semina 

 seu ovula sub-8, quoque loculo biserialia. 



Hab. Found only on tbe sandy stores of the Arctic Sea, at the mouth of the Mackenzie River, lat. 70°. 

 Dr. Richardson. — It is much to be regretted that so interesting a plant as the present, found only in one 

 spot, and that not likely to be again visited by men of science, should be wanting in the very part of the fructi- 

 fication by Tvhich alone its genus can be satisfactorily determined. In habit it agrees almost equally well 

 with Platypetalum as with Braya; but the flowers are larger and far more showy than either, while the ger- 

 men, and, I may add, the remains (a dissepiment) of a former year's capsule, agrees in its comparative 

 length and breadth better with the former than with the latter : but the valves of the germen are remarkably 

 convex, and the style is more than half its length ; so that, in all probability, it ought to constitute a new 

 genus. Dr. Richardson compares the smell of the blossoms to that of Lilac. 



Tab. XVII. A. Plant : — natural size. Fig. 1, Flower ; Jig. 2, Petal ; fig. 3, Stamen ; fig. 4, Germen ; fig. 

 5, More advanced germen ; fig. 6, The same, with the valve (^fig. 7) removed, to show the ovules, or 

 young seeds; fig. 8, Leaf: — more or less magnified. 



23. PLATYPETALUM. Br. 



Silicida ovalis, polysperma, valvis convexis. Stylus brevissimus. Calyx subpatens. Pet- 

 alorum lamince dilatatiE. Cotyledones incumbentes. Br. 



L P. purpurascens ; stigmate bilobo patenti, stylo manifesto, scapis nudis unifoliisque 

 pubescentibus, siliculis glabriusculis. (Tab. XXIII.) — Br. in Parry's \st Voy, App, p. 

 cclxvii, — Braya arctica. Hook, in Parry's 2d Voy, App, p, 387. 



Hab. Arctic shores and islands of America. Capts. JRoss, Parry , Sabine; Dr. Richardson; extending 

 even to Spitzbergen, at Hecla Cove. (Capt. Parry.) — So completely has this the habit of Braya, that, with- 

 out the perfect fruit, it is scarcely possible to distinguish it. Mr, Brown has admirably described it, both 

 generically and specifically, and there remains nothing for me but give a figui-e, which I have done, in part from 

 Melville Island specimens, gathered by Captain James Ross, and in part from Dr. Richardson's, which are 

 generally larger, and have the fruit more oblong in most instances, as seen at C, and fig. 6. 



Tab. XXIII. A, B, et C. Plants: — natural size. Fig. 1, Flower; fig. 2, Petal; ^^f. 3, Stamen; fig. 4, Ger- 

 man; ^^. 5, 6, Capsules; fig. 7, Seed; ^^. 8, Section of seed; fig. 9, Embryo: — magnified. 



2. P. duhium; stigmate indiviso subsessili, siliculis scapisque pubescentibus. — Br. in 

 Parry's \st Voy. App. p. cclxvii. 



Hab. Melville Island. Capt. Sabine. — " Floribus ignotis, dubise generis planta, cujus examplaria tria in 

 Herb, D. Sabine exstant Cotyledones certe incumbentes et lineares, basibus tamen crus radiculare embry- 

 onis vix occupantibus." Br. 



24. EUTREMA. Br. 



Siliqua (abbreviata) anceps, valvis carinatis, dissepimento (nonnunquam) incompleto, 

 Cotyledones incumbentes. — (Herba hahitu omnino Brayae et Platypetali, quibus Tnaxime 



affine gentis, distinguendum facile siliqua ancipiti^ dissepimento incompletOt et seminum funi- 

 culis. Br.) 



