Oreas,] CRUCIFER^. 



67 



1. J5. Edwardsii ; siliculis lanceolatis, dissepimento obliterate, foliis ovato-lanceolatis 

 longe petiolatis. — Br. in Parry's ^st Voy. App, p. cclxvii. t. A, Hook, in Parry's 2d Voy. 

 App. p, 388. 



Hab. Arctic Sea-shore and Islands : first found in Melville Island by Mr. Edtvards and other officers 

 of Captain Ross's Expedition. Coast, eastward of the Coppermine River. Dr. JRichardsun. — The admir- 

 able description and the inimitable figures of this plant, given by Mr. Broun in the Appendix to Captain 

 Parry's First Voyage, leave nothing for me to notice, save that the fructified specimens sometimes attain, 

 if they do not exceed, a foot in length. 



\ 



2. E. arenicola; siliculis lato-linearibus, dissepimento complete, foliis obovato-spathu- 

 iatis. (Tab. XXIV ,)—Bichardson' s MSS. 



^adix perennis, fusiformis, infeme fibrosa, superne saspe multicaulis. Caules plerumquo breves, sed non 

 raro innovatiouibns elongati, ad apicem d'jnse foliati. Folia in rosulam expansa, obovatu, longe petiolata, 

 subcarnosa, glabra, integerrima vel parce dentata, viridia vel purpurascentia, petiolis subunciam longis, basi 

 dilatatis, membranaceis. Scapi digitales, foliosi, foliis subsessilibus obovatis, plerumqne integerrimis. Flares 

 in corymbo parvo dispositi. Cal^x e foliolis 4, basi aequalibus, erectis, late ovalibus, obtusis, glaberrimis, sub- 

 viridi-purpureis. Corolla: Pctala obovata in petiolum attenuata, alba, calyce duplo longiora. Stamitia 6. 

 Filamenta filiformia, alba ; Authercs parvie, subrotundae, didymaa, flavse. Siliqum abbreviate, scu siliculce 6-8 

 lineas longse, in racemum dispositte, pedicello vix duplo longiores, brevissime stipitatse, lato-lineares, ancipiti- 

 subcompressae, Tiridi-fuscas, stigmate subcapitato fere sessili terminatie. Valvce sub lente obscure reticulatim 

 venosse, dorso carinatse, uniuervcs. Dissepimentum completum, membranaceum, album, nonnuuquam (nou 

 semper) linea media obscura longitudinal! notatum. Semina numerosa, 16-20 singulo loculo, subovalia, 

 pallide rufo-fnsca, immargin.ita. Podospermnm breve, gracile. Embryo luteus. Cotyledones plano-com- 

 pressse, paululum canaliculata?, incumbeutes. 



Had, Deep sand upon the shores of Arctic America, between long. 107° and liiO^. 7)r. Richardson, 

 Capt. Sir Mm Franklin and Capt. Back. — This has so entirely the habit of Eutrema Edwardsii^ that, not- 

 withstanding the absence of Mr. Brown's most essential character of that genus, namely the incomplete 

 dissepiment, I cannot hesitate about referring it there. From its place of growth, in deep and moving sand, 

 the stems, which are naturally short, present a singular appearance. In the specimen here figured, for 

 example, the stems are remarkably elongated, and exhibit innovations of four years' growth; each year's 

 shoots having been covered with sand, the succeeding shoots were elongated that the leaves and flower-stalks 

 might rise to the surface. The stalks which produce flowers I consider to be scapes, because, though bearing 

 several leaves, they die down to the root-stems annually. 



Tab. XXIV. Plant :— natural size. Fig. 1, Flower; Jig. 2, Petal; Jig. 3, Stamens; Jig. 4, Pistil; Jig. 5, 

 Siliqua; Jig. 6, Section of do.; Jig. 7, Do. with a valve removed; Jig. 8, Section of a valve; Jig. 9, 

 Seed; Jig. 10, Embryo; Jig. 11, Section of the embryo: — magnijied. 



25. OREAS. CJiam. et Schlecht. 



Cal, basi asqualis, laxus. Pet integra, unguiculata, a;qualia. Filainenta asqualia, eden- 

 tula. >S^3/te brevissitnus, stigmate capitate. Silicula lanceolata, compressa, unilocularis, 

 septe nuUo, valvis planiusculis, nerve medio notatis. Semina plura, evoidea, funiculis 

 umbilicalibus elongatis e supera parte nervi placentarli dependentia, cotyledenibus incum- 

 bentibus. Cham, et Schlecht 



1. O. involucrata. — Chain, et Schlecht, in Linnaa^ v. \. p, 29. t. 30. 



" Herba parva, alpina, perennis, habitu Cardamines bellidifolice. Folia radicalia, petiolata, glabra, 

 caulina nulk; hractea sub pedicellis confertae, jQTolucrum meutientes. Flores brevissime racemosi, brac- 



I 2 



