( 433 .) 
, OROBUS* *. 
Linnean Class and Order. DiADE'LPHiAf, Deca'ndria. 
Natural Order. Legumino'sa;, Juss. Gen. PI. p. 345. — Sm. 
Gram, of Bot. p. 174. — Lindl. Syn. p. 75. ; Introd. to Nat. Syst. of 
Bot. p. 87. — Rich, by Macgilliv. p. 532. — Sm. Engl. FI. v. iii. p. 
259. — Loud. Hort. Brit. p. 509. — Don’s Gen. Syst. of Gard. and 
Bot. v. ii. p. 91. — Legumina'ceje, Loudon’s Arb. Brit. p. 561. — 
PapilioNa'ce-e +, Linn. — Rosales; sect. Cicerin;e; subsect. 
Lotian-e ; type, Lathyrace^e ; subtype, Vicid^e ; Burn. Outl. 
of Bot. pp.614, 638, 642, 659, & 661. 
Gen. Char. Calyx (fig. 1.) inferior, cup-shaped, unequal, with 
5 acute segments ; the two upper shorter and more distant ; the 
lower one longest. Corolla (fig. 2.) papilionaceous, of 5 petals ; 
standard (fig. 3.) inversely heart-shaped, reflexed at the sides, rather 
longer than the rest ; wings (fig. 4.) inversely egg-shaped, ascending, 
approaching each other ; keel (fig. 5.) rounded, pointed, rather 
tumid, of 2 united petals, with separate claws. Filaments (fig. 6.) 10, 
9 united into a compressed tube, open at the upper edge ; the 10th 
hair-like, and distinct. Anthers small, roundish. Germen (fig. 7.) 
oblong, compressed. Style (see fig. 7.) ascending, straight, cylin- 
drical, channelled above. Stigma longitudinal, linear, downy, 
running along the inner, or upper, side of the upper half of the 
style. Legume (fig. 8.) oblong, or linear, tumid, or somewhat 
cylindrical, with a sharp ascending point, of 1 cell, and 2 rigid, 
twisting valves. Seeds (fig. 9.) several, roundish, with a linear hilum. 
The cup-shaped, irregularly 5-cleft calyx, blunt at the base ; the 
slender, strap-shaped style, downy on the upper side, beneath the 
stigma ; the cylindrical, oblong, 1-celled, many-seeded legume ; and 
the leaves without tendrils ; will distinguish this from other genera, 
with diadelphous stamens, in the same class and order. 
Three species British. 
O'ROBUS TUBERO'SUS. Tuberous-rooted Orobus. Bitter- 
Vetch. Heath Pea. Wood Pea. Heath Peaseling. 
Spec. Char. Stem simple, winged, smooth, upright, tuberous 
at the base. Leaves pinnate ; leaflets 2 or 3 pairs, elliptic-spear- 
shaped, smooth. Stipulas half-arrow-shaped ; toothed at the base. 
Peduncles few-flowered, scarcely longer than the leaves. 
Engl. Bot. t. 1153. — Curt. FI. Lond. t. — Linn. Sp. PI. p. 1028. — Huds. FI. 
Angl. (2nd ed. ) p. 314. — Willd. Sp. PI. v. iii. pt. ii. p. 1074. — Sm. FI. Brit. v. ii. 
p. 761. ; Engl. FI. v. iii. p. 272. — With. (7th ed. ) v. iii. p. 837. — Gray’s Nat. Arr. 
v. ii. p. 613. — Lindl. Syn. p. 87. — Hook. Brit. FI. p. 320. — De Cand. Prod. v. ii. 
p. 378. — Don’s Gen. Syst. of Gard. and Bot. v. ii. p. 339. — Macr. Man. Brit. Bot. 
p. 60. — Lightf. FI. Scot. v. i. p. 388. — Sibth. FI. Oxon. p. 221. — Abbot’s FI. Bedf. 
p. 155. — Bryant’s FI. Diaetet. p. 37. — Thomps. PI. Berw. p. 72. — Davies’ Welsh 
Fig. 1. Calyx. — Fig. 2. Corolla. — Fig. 3. The Standard. — Fig. 4. One of the 
Wings. — Fig. 5. The Keel. — Fig. 6. Stamens. — Fig. 7. Germen, Style, & Stigma. — 
Fig. 8. Legume. — Fig. 9. A Seed. — Fig. 10. The tuberous Root. 
• From oro, Gr. to strengthen or invigorate ; and bous, Gr. an ox ; from the 
plants yielding food for cattle. 
+ See folio 77. note t. 
$ See folio 117. note 4, 
