V 



138 .SAXTALACE.E (Hill). [Thesium~ 



A - 



■ 



f- 





Periaiitli-segments with papillose mar- 

 gins ; stout erect slinibs : 

 Plants densely leafy ; Lracts and Lracte- 



oles longer than flowers (16) foiiosum. 



Plants with few scattered leaves ] bracts 



and bracteoles shorter than flowers (17) friiticosura. 



**Flower3 in axillary cymides arranged in many-flowered 



cymose heads, elongated spikes or more or less 

 dense racemes or panicles of cymules ; 

 Plant spinous (18) dissitiflorum. 



Plant not spinous : 

 fFlowers aggregated in compact terminal many- 

 flowered racemose heads : 

 Leaves and bracts broadly ovate-lanceolate, 



amplexicaul (ID) euphorbioides. 



Leaves acicular. terete (20) pinifolium. 



tt Flowers in axillary cymules forming elongated deter- 

 minate spikes or racemes ; plants erect : 

 Cymules ses.^ile in bract-axils ; bracts much 



longer than cymules (21) glomeruliflorum. 



Cymules shortly xiedunculate, compact; bracts 

 shorter than cj'mules : 

 Stems winged (22) angulosuin. 



Stems not winged (23) Susannse. 



ttfFlowers in indeterminate branched racemes ; 



cymules 3-5-flowered ; pedunclei* elongated, 

 divaricately branched ; plants scandent : 

 Leaves and bracts J-1 J in. long : 



Leaves and bracts broadly linear or linear- 

 lanceolate (24) triflorum, 



T 



Leaves fleshy, terete (25) scandens. 



Leaves and bracts less than 3 lin. long (2G) galioides. 



tttfFlowers loosely paniculate : 



Plants .scabrous (27) asperifoliuni. 



Plants glabrous : 



Leaves reduced, about 1 lin. long (28) corynibulige- 



ruui 



Leaves well-developed, J-1^ in. long: 



All leaves about ^ iin. long, numerous and 



recurved ; bracts only slightly adnate 



to peduncles (15) squarxosum. 



Lower leaves J-I^ in. long, all leaves ascend- 

 ing ; bracts adnate for some distance to 



peduncles : 

 Stems 8harj)ly ribbed ; leaves and bracts 



keeled; cymules lax (29) floribundum. 



Stems slightly ribbed ; leaves and bracts 

 more or less rounded on back ; 

 cymules compact (30) pallidum. 



**^Flower3 ananged in small terminal cymose heads or 



clusters : 



Branches fairly densely leafy ; leaves well-developed ; 

 bracts glabrous ; fruits not or scarcely reticulate 

 between ribs : 

 Branches erect ; perianth without external glauds (31) ^uinqueflorum. 



