20 



POACEAE. 



3. Syntherisma longiflora (Eetz.) 

 Skeels. Slender Crab-grass. (Fig. 24.) 

 Culms slender, 1A° long or less, erect or 

 reclining, glabrous. Leaves linear, long- 

 acuminate, glabrous, 6'-12' long, 2"-3" 

 wide; racemes in a terminal whorl of 3-5, 

 or rarely fewer, sometimes 1 or 2 addi- 

 tional ones below, 4' long or less; rachis 

 winged; pedicels hispidulous; spikelets in 

 2 's or 3 's, about f " long, white, elliptic, 

 acute; first scale wanting; second and 

 third scales about equal, 3-5-nerved, ap- 

 pressed-pubescent ; fruiting scale brown, 

 acute. [Paspalum longiflorum Eetz.; Digi- 

 taria longiflora Pers.] 



Abundant on hillsides about Hamilton. 

 Naturalized. Native of Jamaica, Trinidad and 

 tropical continental America. Flowers In 

 summer and autumn. 



7. ECHINOCHLOA Beauv. 

 Usually tall grasses, commonly an- 

 nuals, with broad leaves and a terminal 

 inflorescence consisting of one-sided, ra- 

 cemes, racemosely or paniculately arranged. Spikelets 1-flowered, singly dis- 

 posed, or in smaller racemes or clusters on the ultimate divisions of the in- 

 florescence. Scales 4, the outer 3 membranous, hispid on the nerves, the third 

 and usually also the second scale awned, or sometimes merely awn-pointed, the 

 awn often very long ; fourth scale indurated, shining, frequently pointed, enclos- 

 ing a palet of similar texture and a perfect flower. Stamens 3. Styles distinct. 

 Stigmas plumose. Grain free. [Greek, in reference to the stout hispid hairs 

 of the spikelets.] Species about 12, mostly in warm and tropical countries. 

 Type species : Panicum Crus-galli L. 



Spikelets 3 mm. long, the second and third scales awned. 1. E. Crus-galli. 



Spikelets 2 mm. long ; second and third scales merely awn-pointed. 2. E. colonum. 



1. Echinochloa Crus-galli (L.) 

 Beauv. Barnyard-grass. Cockspur- 

 GRASS. (Fig. 25.) €ulms l°-4° tall, 

 often branching at base. Sheaths 

 smooth and glabrous; leaves 6-2° 

 long, glabrous: panicle composed of 

 5-15 sessile branches; spikelets ovate, 

 green or purple, densely crowded in 

 2-4 rows on one side of the rachis; 

 second and third scales about 11" 

 long, scabrous or hispid, the third 

 scale more or less awned, empty, the 

 fourth ovate, abruptly pointed. 



Waste grounds, Pembroke Marsh, 

 1905, apparently recently introduced as 

 it is not recorded by the older authors ; 

 abundant in Devonshire Marsh. 1914. 

 In cultivated and waste places, through- 

 out North America except the extreme 

 north. Widely distributed as a weed 

 in all cultivated regions. Naturalized 

 from Europe. Flowers in summer and 

 autumn. [Panicum Crus-galli L.] 



