GBAMINEAE (GRASS FAMILY) 



147 



long ; spikelets 5-7 mm. long ; first glume warty-tuberculate on the nerves ; 

 florets stiffly ciliate on the margins. (<7. americanum Spreng.) Wet pine 

 barrens, Va., and southw. Taste very pungent. FIG. 140. 



56. DACTYLOCTENIUM Willd. CROWFOOT GRASS 



Spikelets several-flowered, the uppermost imperfect, sessile and crowded in 

 2 rows along one side of a continuous rhachis, which extends beyond the spike- 

 lets in a naked point ; glumes broad, keeled ; lemmas boat- 

 shaped, cuspidate ; palea equaling the lemma, acute, deeply 

 folded between the ciliate-winged keels ; grain reddish brown, 

 the loose pericarp transversely wrinkled. Annual, with more 

 or less decumbent and creeping base, and 2-6 stout unilateral 

 spikes digitate at the apex of the culm. (Name from 5ci/cTiAos, 

 finger, and KTevtov, a little comb, alluding to the digitate and 

 pectinate spikes.; 



1. D. AEGYPTIUM (L. ) Richter. Usually glabrous ; culms 

 rooting at the lower nodes; spikes 1.5-5 cm. long; glumes 

 scabrous on the keel, the second cuspidate ; the awned tip 

 of lower lemma inflexed, that of the others straight or 

 curved. (D. aegyptiacum Willd. ; Eleusine aegyptia Pers.) 

 Yards and cultivated fields, N. Y., 111., and southw. (Nat. 

 from tropics of the Old World.) FIG. 141. 



141. D. aegyptium. 

 Inflorescence x %. 

 Spikelet x 2. 

 Fruit x 3. Seed x 4. 



142. E. indica. 

 Part of inflorescence x 

 Spikelet and floret x 2. 

 Fruit and seed x 4. 



57. ELEUSINE Gaertn. GOOSE GRASS. YARD GRASS 



Spikelets several-flowered, awnless, florets perfect or uppermost staminate, 



sessile and closely imbricated in 2 rows along one side of a continuous rhachis, 

 which does not extend beyond the terminal spikelet ; 

 glumes unequal, shorter than the floret, scabrous on the 

 keels ; lemmas broader, with a thickened 5-ribbed keel ; 

 palea shorter, acute, the narrowly winged keels distant ; 

 grain black, the loose pericarp marked with comb-like 

 lines, free within the subrigid lemma and palea. Coarse 

 tufted annuals with stout unilateral spikes digitate or 

 approximate at the apex of the culms. (Name from 

 'EXevfflv, the town where Ceres, the goddess of harvests, 

 was worshiped.) 



1. E. fNDicA Gaertn. Glabrous ; culms flattened, de- 

 cumbent at base ; sheaths loose, overlapping, compressed ; 



spikes 2-10, 2.5-8 cm. long ; spikelets appressed, 3-5-flowered, about 5 mm. long. 



Yards and waste ground, Mass., n. 111., Kan., and southw. (Nat. from tropics 



of the Old World.) FIG. 142. 



58. LEPT6CHLOA Beauv. 



Spikelets 2-several-flowered, the uppermost floret usually 

 imperfect or rudimentary, sessile or nearly so, in 2 rows 

 along one side of the slender continuous rhachis ; glumes and 

 lemmas keeled, the latter 3-nerved, acute, awnless or short- 

 awned, exceeding the palea. Usually tall annuals with flat 

 leaves and elongated simple panicles composed of the numer- 

 ous very slender spikes scattered along the main axis. 

 (Name composed of \e7rr6s, slender, and x\6a, grass, from 

 the long attenuated spikes.) 



1. L. filif6rmis (Lam.) Beauv. Culms 4-12 dm. high ; 

 sheaths papillose-hairy ; spikes 20-40, 5-10 cm. long, ascend- 

 ing; spikelets about 3 mm. long; glumes more or less 

 mucronate, nearly equaling the 3-4 awnless florets. (L. 

 mucronata Kunth ; L. attenuata Steud.) Fields, Va. to 

 111., Mo., and southw. Aug. FIG. 143. 



143. L. filiformis. 

 Inflorescence x 1 / w . 

 A part of same with 



2 spikelets x 1%. 

 Spikelet and floret x 3, 



