Genus 38. 



PEA FAMILY. 



395 



A genus of about i6o species, natives of warm and temperate Nortli and South America, South 

 Africa and Australia. Besides the following, about 20 others occur in the southern and southwest- 

 ern States, Our species are known as Tick-trefoil, or Tick-seed. Type species : Hedysarum cana- 

 dense L. 



* Loment not constricted above, deeply constricted below, long-stalked; leaflets broad. 



Panicle arising from the base of the plant ; peduncle usually leafless. i. M. nudiflora. 



Panicle terminal. 



Leaves crowded at its base. 2. M. grandiflora. 



Leaves scattered along the stem. 3. M. fauciflora. 



** Loment constricted on both margins, more deeply below than above. 



t Stems trailing or reclining. 

 Leaflets orbicular or nearly so. 



Leaflets i' long or less, glabrate, coriaceous ; stipules subulate. 4. M. arenicoJa. 



Leaflets i'-2' long, thinnish, usually quite pubescent ; stipules ovate. 5. M. Michauxii. 



Leaflets ovate or oval. 



Corolla whitish : leaves yellowish green ; stipules broadly ovate. 



Corolla purple ; leaves dull green ; stipules subulate. 



tt Stems erect or ascending. 

 Leaves sessile or nearly so ; leaflets linear or lanceolate. 

 Leaves petioled. 



Leaflets narrowly linear ; joints of the loment usually concave on the back. 



Leaflets broad (except in races of M. paniculata). 



1. Joints of the loment notably longer than broad. 



Leaflets obtuse, rough-pubescent, yellowish green. 

 Leaflets long-acuminate. 



2. Joints of the loment little longer than broad. 



(a.) Loment distinctly long-stalked in the calyx. 



Plants glabrous, or nearly so (except in races of M. paniculata) 

 Leaflets lanceolate or oblong. 

 Leaflets broadly ovate or oval, glaucous beneath. 

 Plants pubescent or scabrous. 

 Leaflets thick, coriaceous. 



Leaves villous and reticulated beneath. 

 Leaves velvety-pubescent beneath. 

 Leaflets scarcely coriaceous, appressed-pubescent or villous beneath. 



16. M. Dillenii. 

 (b.) Loment sessile in the calyx, or nearly so. 

 Loment-joints 4-7 ; flowers numerous, showy. 



Leaflets coriaceous, strongly reticulated beneath. 17. M.illinoensis. 



Leaflets not coriaceous, scarcely reticulated beneath ; loments numerous. 



18. M. canadensis. 

 Loment-joints 1-3. 



Leaflets scabrous, i'-2' long. 19- M". ngida. 



Leaflets not scabrous, S"-io" long. 



Plant nearly glabrous throughout. 20. M. marylandtca. 



6. M. ochroleuca. 



7. M. glabella. 



8. M. sessilifolia. 

 o. M. stricta. 



M. canescens. 

 M. bracfeosa. 



12. M. paniculata, 



13. M. laevigata. 



14. M.rhombifolia. 



15. M.viridifiora, 



Stem pubescent ; leaflets and petioles ciliate. 



21. M. obtusa. 



I. Meibomia nudiflora (L.) Kuntze. 



Hedysarum nudiftorum L. Sp. PI. 749. 1753. 

 Desmodium nudiftorum DC. Prodr. 2: 330. 1825. 

 Meibomia nudiflora Kuntze, Rev. Gen. PI. 197. 1891. 



Slender, erect or ascending, the leaves clustered 

 at the summit of the sterile stems, the peduncle 

 arising from the base of the plant, leafless or rarely 

 with I or 2 leaves, 3° high or less. Stipules subu- 

 late, deciduous; petioles i'-4' long; leaflets oval or 

 ovate, glabrous or slightly pubescent, somewhat acu- 

 minate or with a blunt point, pale beneath, I'-j' long, 

 the terminal one rhomboidal, the others inequilateral ; 

 panicles narrow, few-flowered; flowers rose-purple, 

 3"-5" long; bracts deciduous; calyx-teeth obtuse, the 

 lowest one largest; loment 2-3- jointed, the joints 

 longer than wide, straight or concave on the back, 

 obliquely semi-rhomboidal, pubescent with uncinate 

 hairs, the sutures glabrous ; stipe nearly as long as 

 the pedicel. 



In dry woods, Quebec to Minnesota. Florida, Arkansas 

 and Louisiana. July-Aug. 



Naked-flowered Tick-trefoil. Fig. 2576. 



