318 OHIO BIOLOGICAL SURVEY 



ascending branches, the secondary panicles usually included in the 

 sheaths. Spikelets elliptic, pubescent; outer empty glume 3/3 as 

 long as the spikelet. 



In moist ground and thickets. June, July. General. 



54. Leptoldma Chase. Witch-grass. 



Tufted perennial grasses with flat leaves and very diffuse ter- 

 minal panicles which break away at maturity and become tumble- 

 grasses. Spikelets with 1 perfect flower, solitary on long capillary 

 pedicels ; outer empty glume very minute or wanting, inner empty 

 glume 3-nerved, nearly as long as the 5-7-nerved sterile lemma ; 

 fertile lemma indurated, papillose, with hyaline margin not inrolled ; 

 lemma of similar texture ; grain free, enclosed in the flowering 

 glumes. 



1. Leptoloma cognatum (Schultes) Chase. Fall Witch-grass. 

 A perennial slender tufted grass with erect or decumbent stems, 1-2 

 ft. high, usually much branched at the base, and with a loose panicle 

 bearded in the axils, the lower branches at first erect and included 

 in the upper sheath but finally exserted and widely spreading. 

 Spikelets lanceolate, acuminate, on capillary pedicels ; lemma lanceo- 

 late. 



In dry soil. July-Sept. From the West. Lake County. 



55. Syntherisma Walt. Crab-grass. 



Annual, mostly weedy grasses with branched stems, thin flat 

 leaves, and an inflorescence of secund, spike-like racemes which are 

 digitate or approximate at the ends of the branches. Spikelets with 

 1 perfect flower and a vestige of a second one, lanceolate-elliptic, 

 sessile or short pediceled ; empty glumes 1-3 nerved, the outer some- 

 times obsolete; sterile lemma 5-nerved; fertile lemma chartaceous, 

 its margins hyaline and not inrolled ; palet of similar texture ; grain 

 free, enclosed in the flowering glumes. 



1. Rachis of the raceme branches with the angles wingless; outer empty glume 

 wanting or minute; raceme branches 2-5; stems erect. S. filiformc. 



1. Rachis of the raceme branches with the lateral angles broadly winged; stems 

 spreading. 2 



2. Pedicels terete, glabrous or nearly so ; outer empty glume wanting or minute ; 

 raceme branches 2-6. S. ischaemum. 



2. Pedicels sharply 3-angled, the angles hispidulous; outer empty glume present, 

 small, raceme branches 3-12. S. sanguinale 



1. Syntherisma filiforme (L.) Nash. Slender Crab-grass. A 

 slender usually tufted grass with erect stems, 1-4 ft. high, and a 

 panicle of 1-5 spike-like racemes. Spikelets elliptic, pubescent; outer 



