TETRADYNAMIA— SILIQUOSA. Turritis. 215 



very short, with a small, not dilated, stigma. Pods very long, 

 flat, striated, thickened at the edges, curved downwards as they 

 ripen, chiefly towards one side j their valves slightly undulated, 

 not at all keeled. 

 All the difficulty about the genus of this plant, mentioned in Eiigl. 

 Bot. is now happily removed on Mr. Brown's principles. Its 

 glands indeed ''are those of a Brassica,'" but the flat accumbent 

 cotyledons, and simple row of seeds, settle the point. The habit 

 confirms the generic characters, which are altogether those of an 

 Arabis. A. pendula, confounded by Haller with this species, is 

 perfectly distinct. 



341. TURRITIS. Tower-mustard. 



Linn. Gen. 341. Jtiss. 23S. Fl.Br.llo. Comp. ecZ. 4. 108. Br. in 

 Ait. H. Kew. v. 4. 108. DeCand. Syst. i?. 2. 211. Gcertn. t. 143. 

 Arabis. Lam. t. 563. /. 4. 



Cat, erect; leaves oblong, converging, deciduous; 2 opposite 

 ones very slightly protuberant at the basei Pei. obovate- 

 oblong, undivided, erect, not twice the length of the ca- 

 lyx. Filam, thread-shaped, simple, erect, unconnected. 

 Anth, oblong, incumbent. Germ, linear, the length of 

 the petals. Style very short. Stigma obtuse, simple. Pod 

 linear, compressed, very long and slender, crowned with 

 the permanent stigma; valves straight, flat, each with a 

 prominent keel, and quite as long as the linear membra- 

 nous partition. Seeds very numerous, disposed in a 

 double row in each cell, crowded, obliquely pendulous, 

 ovate, compressed, slightly bordered; cotyledons flat, 

 accumbent. 



Upright lierhs^ partly rough, nearly agreeing in habit with 

 the last genus ; nor could any satisfactory mark of dis- 

 tinction between Arabis and Turritis be discovered, till 

 Mr. Brown adverted to the double rows of seeds in the 

 latter, which afford a very peculiar character. Some of 

 his species are thrown out by M. DeCandolle, but they 

 do not concern the Flora of Britain. 



1. T. glabra. Smooth Tower-mustard. 



Radical leaves toothed, rough ; the rest entire, clasping the 

 stem, smooth. 



T. glabra. Li«». .S/?. 7V. 930. Willd.v.3.:^42. Fl.nr.7\:K EnoL 

 Bot. v.W.t. 111. Curt. Loud. fuse. 4. t. 41. Hook. Scot. 2(H). 

 DeCand. Syst. r . 2. 2 1 1 . FL Dan. t. S09. Ehrh. Ikrb. I 11). 



T. n.4r)r>. Hall, llist.v. 1. 11)8. 



Turritis. Ihui S,j,i. 203. Gcr. Em. '171. f. L<>h. It. 220, /'. 



