Seventeenth class. 
35 
Cl. 17. Diadelphia. 
1. Seps 5, persist.; 2 larger than the others, coloured 
(wings). Stas 8, united in bundles of 4. Ls undiv., entire 
Polygala. 88. 
— Seps 2, decid. Stas 6, in bundles of 8. Ls 2-ternatisect 
or 2—3-pinnatisect ...... 2 
— Cal. gamosep., persist. Stas 10, 9 united and 1 free. Ls 
pinnate or digitate, rarely simple (cor. papilionaceous). 
Here are found nearly all the Pajpilionacece . 3 
2. Fr. an indehisc. nut, oval or globular, l-seeded. FIs 
small (5—12 mm) .... . Fumaria. 29. 
— Fr. a long, silicular, several-seeded caps., opening by 2 
valves. FIs larger ..... Corydalis. 28. 
3. Ls all simple, entire .... Lathyrus. 160. 
— Ls digitate, with 3 leaflets (sometimes large stipules 
resembling leaflets make them appear to have 5 leaflets, 
or to be pinnate) ....... 4 
— Ls imparipinnate (with a terminal leaflet; leaflets 
gen. more than 7) ...... 10 
— Ls paripinnate (sometimes with only 1 pair), (the 
terminal leaflet replaced by a tendril, a point or a spine) It) 
4. Keel rostrate. (Leaflets entire) .... 
— Keel obtuse ........ 6* 
5. Pod 4-winged. FIs yellow or red, single or in pairs 
Tetragonolcbus. 147. 
— Pod not winged. FIs yellow, in head-shaped umbels of 
3—12 fls.Lotus. 146. 
6. Stipules large, resembling the leaflets and forming with 
them a 5-digitate leaf. Fls small, gen. with a dark-blue 
keel. Leaflets entire . . . Dorycnium. 145. 
— Stipules not resembling the leaflets ... 7 
7. Cor. withering persist. Pod gen. enclosed. Clover 
Trifolium. 144. 
— Cor. decid. Pod reaching beyond the calyx . . 8 
8. Cotyledons sessile or narrowed into the petiole without 
a joint. Pod reniform, sickle-shaped or rolled spirally 
Medicago. 141. 
— Cotyledons joined to the petiole by a joint . 9 
9. Pods linear or oval-oblong, but then beaked and the 
fls blue. Fls blue, in head-like racemes with long ped¬ 
uncles, or yellow in almost sessile umbels Trigonella. 142. 
— Pods oval, not beaked. Fls yellow or white, in long 
racemes .Melilotus. 143. 
10 (3). Fls solitary. Leaflets toothed . . . Cicer. 158. 
— Fls in umbels. Leaflets entire ... 11 
— Fls in racemes or spikes ..... 13 
11. Keel obtuse 
Ornithopus. 154. 
