POACEAE. 



19 



1. Syntherisma sanguinalis 

 (L.) Dulac. COMMON CRAB- 

 GRASS. (Fig. 22.) Culms 2} 

 long or less, finally branched, 

 prostrate at the base and root- 

 ing at the lower nodes. Lower 

 leaf-sheaths densely papillose- 

 hirsute; blades 2"-5" wide, 

 erect or ascending, glabrous or 

 more or less pubescent: racemes 

 2-9, l'-5' long, erect or ascend- 

 ing, alternate, in pairs or 

 whorls; spikelets about I*" 

 long, lanceolate, very acute, in 

 pairs; first scale small, gla- 

 brous, the second and third ap- 

 pressed-pubescent with long 

 hairs, the second one 3-nerved, 

 the third slightly exceeding the 

 flowering scale, 7-nerved, the 

 pubescence usually becoming 

 widely spreading, the fourth 

 one lanceolate, very acute, yel- 

 lowish-white at maturity. [Pan- 

 icum lineare of Lefroy; Pani- 

 cum sanguinale L. ; Digitaria 

 marginata Link ; Syntherisma 

 marginatum Nash.] 



Common in waste and cultivated grounds, often a pernicious weed. Naturalized. 

 Southern United States ; Bahamas ; tropical South America. The characters relied 

 upon by authors to separate S. marginatum from S. sanyuinale do not appear to be 

 specific. 



2. Syntherisma digit at a (Sw.) 

 Hitchc. NARROW CRAB-GRASS. (Fig. 23.) 

 Culms li-3 long, branched, tufted, at 

 length decumbent below and rooting at 

 the lower nodes. Leaves more or less 

 densely hirsute, l'-5' long, l"-3i" wide; 

 racemes several, 14'-5i' long, whorled or 

 alternate or approximate in pairs, widely 

 spreading; rachis very narrow,'^ spikelets in 

 pairs, about 1" long, lanceolate, acuminate; 

 first scale minute, glabrous; second scale 

 3-nerved, appressed-pubescent ; third scale 

 7-nerved, also appressed-pubescent; fruit- 

 ing scale nearly 1" long, shorter than 

 the third, elliptic, greenish when mature. 

 [Hilium digitatum Sw. ; Digitaria, setigera 

 Roth; Panicum liorisontale Meyer.] 



Bermuda (according tc Lefroy, and North 

 American Flora 17: 154). Florida; West In- 

 dies ; tropical continental America. 



