GENUS 92. 



GRASS FAMILY. 



261 



25. Poa confusa Rydb. Tufted Spear- 

 grass. Fig. 628. 



P. confusa Rydb. Bull. Torr. Club 32 : 607. 1906. 



Culms densely tufted, ii-3 tall, erect, slender; 

 sheaths smooth and glabrous; ligule t?"-i" long, 

 obtuse or acutish, hispidulous on the outside ; 

 blades up to 8' long, \"-\\" wide, flat or involute, 

 puberulent ; panicle narrow, 4' -6' long, its branches 

 short and appressed ; spikelets about 4" long, com- 

 monly 4-flowered, the empty scales shining, strigu- 

 lose above, the flowering scales narrow, a little 

 less than 2" long, obtuse or rounded at the apex, 

 rounded on the back below, hispidulous. 



In open places and on hills, Nebraska and Montana 

 to Colorado. June-Aug. 



93. DUPONTIA R. Br. Parry's Voy. App. 290. 1824. 



Low grasses, with flat leaf-blades and generally narrow panicles. Spikelets 2-4-flowered, 

 the flowers all perfect. Two lower scales empty, extending beyond the flowering scales, 

 membranous; flowering scales entire, membranous, with a tuft of hairs at the base. 

 Stamens 3. Styles distinct. Stigmas plumose. [Name in honor of J. D. Dupont, French 

 botanist.] 



Two arctic species, both circumboreal. Type species: Dupontia Fishcri R. Br. 



i. Dupontia Fisheri R. Br. Fisher's Du- 

 pontia. Fig. 629. 



D. Fisheri R. Br. Parry's Voy. App. 291. 1824. 



Smooth and glabrous, culms 5'-i2' tall, erect, 

 simple. Sheaths overlapping; ligule i" long or 

 less; blades i'-6' long, i"-2" wide, flat; panicle 

 usually contracted, i-^ long, the branches 

 less than ii' long, erect, or sometimes ascend- 

 ing; spikelets few, about 2-flowered, 3 "-4" long; 

 empty basal scales thin, generally acute, the first 

 i-nerved, somewhat shorter than the second, 

 which is usually 3-nerved, the lateral nerves often 

 vanishing at about the middle ; flowering scales 

 2i"-3" long, i -nerved or obscurely 3-nerved; 

 basal hairs about \" long. 



Arctic regions of North America. Also in arctic 

 Europe and Asia. Summer. 



94. SCOLOCHLOA Link, Hort. Berol. i : 136. 1827. 



Tall aquatic or marsh grasses, with flat leaf-blades and ample panicles. Spikelets 

 2-4-flowered, the flowers perfect. Two lower scales empty, thin-membranous, 3-5-nerved; 

 flowering scales rigid, with a tuft of hairs at the base, rounded on the back, 5-j-nerved, some 

 of the nerves usually excurrent as short points ; palets about equalling the scales, 2-nerved. 

 Stamens 3. Styles very short. Stigmas plumose. Grain hairy at the apex. [Greek, referring 

 to the prickle-like projecting nerves of the flowering scales.] 



Species 2, in the north temperate zones of both continents. Type species : Arundo festucacea 



Willd. 



