DIADELPHTA. DECANDRIA. 55 



pressed, caritiatc, villous on the uj)per side. 

 Suture of the legume iiakvd. 



Stem scandirnt or d fi'use; peiiole manv-leaved, leaflets 

 and biipiiles larg'C; peduncles axillary, 1 or maiiv-Houcr- 

 ed. 



Species. 1. V. maviihmim. Abundant on the sliorcs 

 of Liikts Erie, Huraii and .Miclii^^an, but differs fiom the 

 European species in h.avuig a pubescent legume. 



At present there are but 4 species of this genus, indige- 

 DOMS to Europe and Egypt, but the habitat of the garden 

 pea {P. sativum) I'ke tliat of man} other important plants 

 in human diet, apjjcars not to have been ascertained. 



495, 0R013US. L. (Bitter-Vetch.) 



<S7?/-e linear. Ccro'la long. Calix obtuse at 

 the base; upper segmetits deeper and mostly 

 shorter. 



Stem herbaceous, ofren erect; leaves conjugate, bi ju- 

 gate or pinnate, mostly terminated by a short and straight, 

 undivided, setiform tendril; stipules mostly semisaglttate; 

 flowers racemose, axillary and terminal. 



Species. 1. O. * dispar. Leaves unequally pinnate, 6 

 to 8 pair, leaflets linear, obtuse; stipules simpl^^ ovate, 

 acute; racemes sessile, filiform, it or 3 together; segments 

 of the cahx equal, the uppermost indenture deeper and 

 wider. IIae. (Jn arid hills near I'ort Mandan. I'lowering 

 in June. Obs. 'I'his and the following species differ very 

 rema'kably from the usuil liabit of the genus, but analy- 

 ticiilly compared with Orobiis tylvciicus, now before n:e, 

 they ajjpear to be inseparable congeners. Root perennial. 

 Stems numerous, decumbent, branched, terete below, an- 

 gular above, rigid, a little pubescent in common with the 

 rest of the plant. Racemes about the length of the leaves; 

 flowers remote, ochroleuous; the calix obtuse at the base, 

 dentures subacuminate; wings longer than the carina; 

 style and minute stigma nearly smooth; legume many- 

 seeded, smooth and flat, acute and curved at the point, at- 

 tenuated at the base; seeds 6 to 8, about the size of small 

 A'ctches. The habit of this plant is more that of Astraga- 

 lus than Orobus. 



-2. * longifrJms. Sericeously villous; leaves ternate and 

 bijugate, uppermost simple, leaflets very long and fili- 

 formly hnear; stipules undivided, ovate-lanceolate, acumi- 

 nate; racemes pedunculate, filiform, often solitary, shorter 

 than the leaves; the 2 upper dentures of tlie calix shorter. 



