GRIFFITHS THE GRAMA GRASSES. 369 



of the culm. There are no differences between them in the spikelets and floral details. 

 Miguel Bang's no. 81, of the John Donnell Smith collection, combines these two 

 characters in one plant. Both of the Philippi specimens are from the Province of 

 Tarapaca in the extreme northern part of Chile. South American material is very 

 scanty in North American herbaria, and it may be that when more of it becomes 

 available a still closer relation will be shown between this and B. procumbens. 



HERBARIUM SPECIMENS. 



South America: Fries 1058a, Bolivia; 813, Argentine. Bang 81, Bolivia. Philippi, 

 267 and 208, Chile. Rushy 34, Bolivia. Stuckert, Herb. Argent. 17700. 



3. Bouteloua stolonifera Scribn. 





Bouteloua stolonifera Scribn. Proc. Acad. Phila. 1891 : 302. 1891. The type is 

 Pringle 3174, in the U. S. National Herbarium, from Honda Station, Zacatecas, Mexico, 

 August 19, 1890. 



DESCRIPTION. 



A densely tufted, strongly stoloniferous, low, smooth perennial; sheaths short, 

 indistinctly striate; blades flat, narrow, 3 to 5 cm. long, with involute edges, minutely 

 scabrous under a lens, abundant and mostly radical; spikes solitary upon short, erect 

 or ascending culms, 5 to 10 cm. high, recurved into a circle when mature, 2 to 2.5 cm. 

 long; spikelets lax, 15 to 20, pectinate, about 15 mm. long including awns; glumes 

 lanceolate, acuminate, the first 5 and the second 8 mm. long, smooth or minutely 

 hispidulous on the keel; lemma smooth, 8 to 10 mm. long, including 3 long, unequal, 

 hispid awns, the central 1 to 2 mm. longer than the lateral; palet about 5 mm. long, 

 narrow, with involute margins, the 2 awns about 1 mm. long; rudiment consisting of 

 2 or 3 aborted florets in the shape of 5 to 8 or more long, hispid awns and 3 to 5 small 

 scales upon a short stipe about 1 mm. in length; caryopsis not seen. (Figure 30.) 



When not headed out this species resembles somewhat the female plants of Bulbi- 

 lis dactyloides. It often grows thick enough in shallow depressions in the mesas to 

 make a semblance of a turf. Extensive areas of it have not been seen. 



HERBARIUM SPECIMENS. 



Mexico: Lloyd 104, Cedros, Zacatecas. Schaffner 1879, San Luis Potosi. Pringle 3174, 

 La Honda Station, Zacatecas. 



4. Bouteloua scorpioides Lag. 



Bouteloua scorpioides Lag. Gen. & Sp. Nov. 5. 1816. This species is identified 

 on no other evidence than the brief description, "Culmo erecto filiformi mono- 

 stachyo: spica lineari-oblonga spiraliter revoluta," and the additional information 

 that the plant is from "N. Hisp." and perennial. Fournier referred this to Chondro- 

 sium tenue H. B. K., to which it is closely allied, the difference between them con- 

 sisting chiefly in the perennial character of Bouteloua scorpioides. Fournier does not 

 appear to have seen this species at all and consequently it was perfectly natural for 

 him to refer this name to the annual C. tenue, which it so closely resembles. 



Actinochloa ? scorpioides Roem. & Schult. Syst. Veg. 2: 420. 1817. Based upon 

 Bouteloua scorpioides Lag. 



Atheropogon scorpioides Spreng. Syst. Veg. 1: 293. 1825. Based upon Bouteloua 

 scorpioides Lag. 



Chrondrosiumf scorpioides Kunth, Rev. Gram. 1 : 94. 1829. Based upon Bouteloua 

 scorpioides Lag. 



