TRIAXDRIA, DIGYNIA. 71 



Crab-grass. Crop'grass. Turd-grass. Crow-foot- 



grass. 



Very common every where on road -sides and even in 

 the cre\ icon of the bricks on our pavements in this city. Pe- 

 rennial. July. 



65. Anthopogon, Nuttall, Gen.Am.pl. 81. ( Graminex.) 



Flowers polygamous, irregularly alternating 

 upon setaceous spikes disposed in a panicle. 

 — Calix 2-valved, 2-flowered, one of the 

 lowers in the form of an abortive pedicellate 

 seta, valves rigid, subulate, and unequal, 

 growing to the impressed angular rachis. 

 rulla, hermaphrodite, 2-valved, outer 

 valve terminated by a long and straight awn. 

 Afattral rudiment pedicellate, of one minute 

 valve going out into an awn. Seed linear- 

 oblong, internally marked with a longitudi- 

 nal furrow. Xutt. 



1. A. culm 18 inches to 2 feet high, decumhent at Ltftmniim. 

 the base, upwards assurgent and erect, leafy with 

 ihort and numerous articulations Leaves short, 

 ovate lanceolate, very acute, smooth, flat. Pani- 

 cle Btlb-verticillate ; spikes or racemes numerous 

 (20 to 30) simple, setaceous and verv long ; ra- 

 chis angular, scabrous. Flowers interrupted, ap- 

 proximating towards the extremities, appressed to 

 the rachis. CaL 2-valved, 2-flowered, growing to 

 the rachis. Cor, hermaphrodite, 2-valved. Stam. 

 exserttd. Styles 2. Stigma plumose. Seed 

 naked, linear-oblong. Xutt. 



A. ambiguum, Mich. 



A singular and pretty frrass, for specimens of which I am 

 iadebtea to Mr. Nuttall, not having met with it myself. In 

 tke * 'Jersey a mile or two from the Delaware. Mr. 



Nuttall. Perennial. 



