POACEAE. 



37 



1. Eustachys petra^a (Sw.) Desv. 

 West Indian Grass. (Fig. 55.) Culms 

 l°-3° tall: leaf -blades 1° long or less, 

 3"-5''' wide, smooth: spikes 3-11, usually 

 4-6, erect, lV-4:' long: spikelets about 1" 

 long: scales 4, the second, exclusive of the 

 awn, about 5" long, 2-toothed at the 

 apex, the teeth triangular, acute or ob- 

 tusish, the awn about i" long; third scale 

 about 1" long, in side view elliptic and 

 about i" wide, the awn short or wanting; 

 fourth scale in side view obovate-elliptic, 

 rounded at the apex, awnless. [Chloris 

 petraea Sw.] 



Common in dry soil, a weed in cultivated 

 grounds. Naturalized. Native of the south- 

 eastern United States, West Indies and trop- 

 ical continental America. Flowers from 

 spring until autumn. 



28. ELEUSINE Gaertn. 

 Tufted annual or perennial grasses, with flat leaves and spicate inflores- 

 cence, the spikes digitate or close together at the summit of the culm. Spike- 

 lets several-flowered, sessile, closely imbricated in two rows on one side of the 

 rachis, which is not extended beyond them; flowers perfect or the upper 

 staminate. Scales compressed, keeled; the 2 lower empty; the others subtend- 

 ing flowers, or the upper empty. Stamens 3. Styles distinct. Stigmas plu- 

 mose. Grain loosely enclosed in the scale and palet. [From the Greek name 

 of the town where Ceres was worshipped.] Species 6, natives of the Old 

 World. Type species: Cynosurus coracanus L. 



1. EJeusine Indica (L.) Gaertn. 

 Wire-grass. Crab-grass. Yard-grass. 

 (Fig. 56.) Culms 6-2° tall, tufted, 

 erect, or decumbent at the base. Sheaths 

 loose, overlapping and often short and 

 crowded at the base of the culm, gla- 

 brous or sometimes sparingly villous; 

 leaves 3'-12' long, l"-3" wide, smooth 

 or scabrous; spikes 2-10, l'-3' long, 

 whorled or approximate at the summit 

 of the culm or one or two sometimes 

 distant; spikelets 3-6-flowered, lA"-2" 

 long; scales acute, minutely scabrous on 

 the keel, the first 1-nerved, the second 

 3-7-nerved, the others 3-5-nerved. [Cy- 

 nosurus indicus L.] 



Common in fields, dooryards and waste 

 places. Abundant over North America ex- 

 cept the extreme north. Naturalized from 

 the warmer regions of the Old World. 

 Flowers nearly throughout the year. 



