GENERA OF GRASSES OF THE UNITED STATES. 191 



Chloropsis Hack. ; Kuntze, Rev. Gen. PI. 2 : 771. 1891. The name was men- 

 tioned by Hackel 1 as a synonym under Trichloris. Hackel also mentions 

 Chloridopsis, both names having been used by gardeners for Trichloris blan- 

 chardiana Hack, of Argentina. Kuntze changes the name Trichloris to Chlor 

 opsis, because of the earlier Trichlora Baker. Both Trichlora and Trichloris 

 may be considered valid, since they have different derivations and slightly 

 different spellings. Since Kuntze adopts Hackel's name and since Hackel 

 mentions Chloropsis blanchardiana, this species is selected as the type of 

 Chloropsis. 



The two species of the United States, Trichloris mendocina (Phil.) 

 Kurtz (T. fascieulata Fourn.) (fig. 113) and T. plwriflora Fourn., 

 are found in the arid regions of northern Mexico and extend into 

 western Texas, southern New Mexico, and southern Arizona. The 

 first has spikelets with one perfect floret and a rudiment, each with 

 three long awns; the second has spikelets with 3 to 5 florets, the 

 upper one or two reduced, the lateral awns reduced or sometimes 

 wanting. Neither is of importance agriculturally. 



95. BOTJTELOUA Lag., the grama grasses. 



Spikelets 1 -flowered, with the rudiments of one or more florets 

 above, sessile, in two rows along one side of the rachis; glumes un- 

 equal, 1-nerved, acuminate or awn-tipped, the first shorter and nar- 

 rower; lemma as long as the second glume or a little longer, 3-nerved, 

 the nerves extending into short or often rather long awns, the in- 

 ternerves usually extending into teeth; palea 2-nerved, sometimes 

 2-awned; rudiment various, usually 3-awned, a second rudimentary 

 floret sometimes present. 



Perennial or sometimes annual, low or rather tall grasses, with two 

 to several or many spikes racemose on a common axis, or sometimes 

 solitary, the spikelets few to many in each spike, rarely solitary, 

 pectinate or more loosely arranged and appressed, the rachis of the 

 spike usually produced beyond the insertion of the spikelets. Spe- 

 cies 38, all American and chiefly North American; 18 species found 

 in the United States, mostly in open grassland of the southwestern 

 States. 



Type species : Bouteloita racemosa Lag. 



liouteloua Lag., Varied. Cienc. Lit. and Art. 2 4 : 134. 1805. Lagasca gives 

 five species, B. racemosa, B. hirsuta, B. barbata, B. simplex, and B. prostrata. 

 All ;;re briefly described, except the last, which is mentioned by name only. The 

 first species (which is the same as B. curtipendula) is selected as the type. In 

 this work Lagasca spells the name of the genus " Botelua " and states that he 

 names the genus in honor of the two brothers Boutelou. In a later work 2 

 Lagasca describes the genus under the name Bouteloua, and includes 10 species, 

 the first of which is B. htysuta. The spelling Bouteloua is retained because it 

 was corrected to this form by the author to correspond to the spelling of the 

 personal name of the brothers Boutelou, and because this second spelling has 

 been universally accepted by botanists. 



Atheropogon Muhl. ; Willd., Sp. PI. 4: 937. 1806. A single species is described, 

 A. apludioides Muhl., which is Bouteloua curtipendula. 



Triathera Desv., Nouv. Bull. Soc. Philom. Paris 2: 188. 1810. Based on 

 Aristida amtrwana L., which is Bouteloua americana (L.) Scribn., a West 

 Indian species. 



*In Engl. and Prantl, Pflanzeafam. 2 2 : 59. 1887. 2 Gen. and Sp. Nov. 5. 1816. 



