152 DB. 1I00KEB AND DE. THOMSON'S PItyECURSOB.ES 



Hab. In Kunawur et Tibetia occidentali alpina. — Var. a, in Piti ! et 



Nubra ! alt. 15000-18000 ped., T. T. ; var. (3, Nubra ! et Zanskar ! alt. 



13000-17000 ped., T.T. (fl. Sept.) (v.v.) 



Distr. In alpibus Siberia; ! terrisque arcticis Europa: ! Asiae ! et America? ! 



Best distinguished by the small, tufted habit, lanceolate, ciliate or 



pilose (not white tomentose) foliage, shortish, slender, leafless scapes, 



and subcapitate racemes of small, broad, acute pods. It approaches some 



Arctic American forms and D. rupestris of Britain, but is hardly identical. 



The var. a exactly accords with Karelin's and KiriloiF's specimens. 



!). D. Armena (Boiss.l Ann. Sc. Nat. ser. 2, vol. xvii. p. 167). Par- 

 vida, caespitosa, tota cano-tomentosa, foliis spathulatis v. obovato- 

 lanceolatis, scapis mulis paucifloris, siliquis ellipticis acutis non tortis 

 cano-tomentosis pedicellis longioribus stylo brevi apiculatis. 



Hab. In Affghanistan, Kohi Baba, alt. 14000-15000 ped. I Griffith. 



D. Wahlenbergii affinis, differt tomento foliorum cano et siliquis eano- 

 tomentosis. 



10. D. Tibetica (H.f. 8f T). Laxe csespitosa, molliter cano-tomentosa 

 v. lanuginosa, foliis spathulato-lanceolatis acutis integerrimis, scapis 

 elongatis gracilibus nudis, pedicellis elongatis, sepalisque canis, flori- 

 bus magnis, siliquis elliptico- v. lineari-lanceolatis planis tortisve cano- 

 tomentosis glaberrimisve, pedicellis gracilibus brevioribus, stylo brevi- 

 usculo. 

 V T ar. a. Thomsoni. Foliis cano-tomentosis, siliquis planis, stylo brevi. — 



Ad D. lasiophyllam tendit. 

 Var. /9. Sikkimensis. Foliis lanuginosis, siliquis tortis, stylo valido elon- 



gato. — Ad D. incanam tendit. 

 Var. y. Winterbottomi. Foliis appresse cano-lanuginosis, siliquis lineari- 

 lauceolatis angustioribus planis glabris, stylo brevi gracili". — Ad D. 

 Wahlenbergii siliquis tendit. 

 Hab. a, in Tibetia occidentali alpina, Zanskar, alt. 13000-15000 ped. I 

 T.T. ft in Tibetia occidentali, alt. 14000-1 6000 ped. ! J. D. H. (fl. 

 Jun.-Jul.) (v.v.) y, in Tibetia occidentali, Balti ad Deotsa et Tak- 

 hala, alt. 11000-13000 ped.! Winterbottom. 

 Caules interdum graciles, elongati. Folia ^-l" long. Scapi spithamsei, 

 rarius unifoliati. Flores albi (v. interdum lutei, T. T.), \" lati. Sili- 

 quee erectse ; pedicellis suberectis, \-l" long. 

 I have reluctantly brought these three forms under one species, having 

 each from a single small province only of the Himalaya or Tibet. In the 

 aggregate they may best be distinguished by the tufted habit, white, woolly 

 or tomentose, quite entire acute spathulato-lanceolate leaves, almost in- 

 variably leafless scapes, long pedicels, and large flowers. The pods present 

 wide variations : they are racemose, tomentose, elliptic-lanceolate, and 

 much shorter than the pedicels in a and /3 (twisted, with long stout styles 

 in ; flat, with short styles in a), but longer, narrower, quite glabrous, and 

 almost capitate in y. All the specimens from each locality agree perfectly ; 



