CRUCIFER.E. 



147 



hone-radish, and in the leaves of Lepidium latifolium which ad- 

 ministered act powerfully upon the gastric organs, or applied ex- 

 ternally inflame the skin and operate nearly as severely as blis- 

 ters. A slighter degree of acrimony is found in the scurvy-grass, 

 and the roots of the garden- radish, &c. and these therefore 

 operate more gently and perhaps more safely when eaten, and 

 scarcely at all when applied to the skin. Whatever may be the 

 degree of acrimony in these plants, they all appear when eaten to 

 produce some specific action upon the digestive organs, and thence 

 upon scorbutic humours, for which reason the horse-radish, 

 water-cress, garden-radishes, and even cabbages are eminently 

 anti-scorbutic. They are also admitted by physicians as diuretic, 

 sialogogue, and diaphoretic. It is only when the acrid principle 

 is diffused over a considerable quantity of fleshy and watery sub- 

 stance that cruciferous plants become eatable, as in the leaves and 

 stems of cabbages, cauliflowers, and sea-kale, and in the roots of 

 radishes and turnips. It is to be remarked that cruciferous plants 

 are always eatable when their texture is succulent and watery. 

 Even in these plants the proportion of acrid principle is much di- 

 minished by exclusion from light. Plants of this order are also 

 remarkable for containing a greater quantity of azote than most 

 vegetables, for which reason ammonia is generally evolved in their 

 fermentation or putrefaction, to which circumstance it is possible 

 that the two remarkable phaenomena are to be attributed, viz. 

 that cruciferous plants contain a greater portion of nutritive 

 matter than most herbaceous plants, and that they require either 

 a very rich soil, manured with animal substance, or at least a 

 situation near the habitation of men. The embryos of all these 

 plants are filled with oil, and the seeds of Camelma satlva, Brassi- 

 ca campestris, var. oleifera, some species of Rocket, &c. are culti- 

 vated in many parts of Europe for the sake of their expressed 

 oil, which is used either for culinary purposes or for lamps. 

 (Decandolle, syst. 2. p. 143 and 144.) 

 Synopsis of the Genera, 



SUBORDER I. PLEURORHI'- 

 ZEJE. D. C. syst. 2. p. 146. 

 prod. 1. p. 132. 



Cotyledons fiat, accumbent (f. 

 46. c. f. 45. .). Radicle lateral 

 (f. 45. h. g. d.\ Seeds compressed 

 (f. 46. g. h.]. 



TRIBE I. 



ARABI'DEJE or PLEURORHI'ZEJE. Siliquosce. D. C. syst. 2. p. 

 146. prod. 1. p. 132. 



Silique dehiscent, with a linear dissepiment, which is, more or 

 less, broader than the seeds ( f. 46. b.). Seeds oval, compressed, 

 usually margined. Cotyledons flat, accumbent (f. 46. c. f. 45. g. 

 d. h.~), parallel with the dissepiment. 



1 MATHI'OLA. Silique somewhat cylindrical. Stigmas con- 



nivent, thickened or horned on the back (f. 48. 6.). Calyx 

 besaccate at the base. 



2 CHEIRA'NTHUS. Silique terete or compressed. Stigma 2- 

 lobed or capitate. Calyx besaccate at the base. 



3 NASTU'RTIUM. Silique rather terete, short, or declinate. 

 Stigma somewhat 2-lobed. Calyx equal at the base, spreading. 



4 LEPTOCARP* V A. Silique rather terete, very slender. Stigma 

 sessile, 2-lobed. Calyx spreading, equal. 



5 NOTO'CERAS. Silique tetragonally 2 -edged ; each valve 

 ending in a mucrone or horn at the top (f. 46. a.). 



6 BARBARE'A. Silique tetragonally 2-edged ; valves without 

 a mucrone or horn at the top. Calyx equal at the base. 



FIG. 46. 



7 STEVE'NIA. Silique oblong, few-seeded, narrowed between 

 the seeds (f. 46. 6.) ; valves flat, somewhat torulose. Calyx 

 bisaccate at the base. 



8 BRA'YA. Silique oblong, somewhat cylindrical, with flattish 

 valves and a sessile stigma. Seeds few, ovate. Calyx equal at 

 the base. Cotyledons perhaps incumbent. 



9 TURRI'TIS. Silique linear ; valves flat. Seeds in 2 rows in 

 each cell. 



10 A'RABIS. Silique linear ; valves flat, with a nerve in the 

 middle of each. Seeds in one row in each cell. 



11 OUDNE'YA. Silique sessile, linear, beaked; valves flat, 

 with a nerve in the middle. Seeds in 1 row. Stigmas connate, 

 distinct at the top. Calyx closed, bisaccate at the base. 



12 MACROPO'DIUM. Silique linear, stalked ; valves flat, with 

 a nerve in the middle. 



13 CARDA'MINE. Silique linear ; valves flat, nerveless, usually 

 separating with elasticity. Umbilical cord slender. 



14 PTERONEU'RUM. Silique lanceolate ; valves flat, nerveless, 

 usually separating with elasticity. Placentas with nerved wings. 

 Umbilical cord dilated. 



15 DENTA'RIA. Silique lanceolate ; valves flat, nerveless, 

 usually separating with elasticity. Placentas not winged. Um- 

 bilical cord dilated. 



16 PA'RRYA. Silique broad-linear ; valves flat, more or less 

 distinctly veined. Seeds with broad margins, disposed in some- 

 thing like 2 rows. Umbilical cord adnate to the dissepiment above. 

 Lobes of stigma approximate. Calyx bigibbous at the base. 



TRIBE II. 



ALYSSI'NES or PLEURORHI'ZE^; LATISE'PT*. D. C. syst. 2. 

 p. 147. prod. 1. p. 156. 



Silicle opening longitudinally ; dissepiment broad-oval, me 

 U 2 



