60 Rhodora [March 



bridge over the gap between these forms. It has seemed wise, 

 therefore, to proceed for the present on a conservative basis, and 

 treat these forms as varieties of a common stock. E. muricaia in 

 this broad sense is a well-defined unit characterized by the acute 

 coriaceous lemma, short nodal hairs and the general reduction or 

 absence of branch-setae. 



The var. ludoriciana, when well developed, differs from the typical 

 form of E. muricata in the muticous spikelets, great reduction of 

 spicules and dense inflorescence. The var. occidentalis is the less 

 bristly, often awn-pointed extreme of the small-spikeleted micro- 

 stachya type. Var. microstachya is densely bristly as is the typical 

 form of the species, but the spikelets are smaller and more gener- 

 ally muticous, and the color of the panicle is usually dark chocolate- 

 brown. The var. uiulti flora resembles var. microstachya but the 

 panicle is larger and more open, and the spikelets more acuminate 

 and slightly less bristly. The anthers vary slightly through the 

 different varieties, though they are remarkably constant for each 

 variety. The smallest anthers are those of var. microstachya and the 

 largest those of typical E. muricaia. The anthers of var. micro- 

 stachya are indeed the smallest in the genus. Some specimens of 

 the typical form of the species from Georgia and Florida have awned 

 upper glumes. It will be noted that in general the variations of 

 E. muricata are geographical. Whether Pursh's names Pamoum 

 crusgalli /3 mite and y purpureum apply to forms of this species or 

 to variations of E. crusgalli cannot now be determined. 



6. E. echinata (Willd.) Beauv. Agrost. 53 (1812). Panicum 

 cchinatum Willd. Enum. PI. Berol. 1032 (1809). Oplismentis crus- 

 pavonis HBK. Gen. et Sp. i. 88 (1815). E. sabulicola Hitchc, Contr. 

 U. S. Nat. Herb. xvii. pt. 3, 257 (1913), probably not Panicum sab- 

 ulicolum Nees. Agrost. Brasil. 258 (1829). E. crusgalli crus-jxivonis 

 Hitchcock, Contr. U. S. Nat. Herb. xxii. pt. 3, 148 (1920).— Mexico 

 through Central America to northern South America and Brazil. 

 Mexico: Saltillo, Coahuila, 1898, E. Palmer, no. 418; Durango, 

 1896, E. Palmer, no. 730; Guadalajara, Jalisco, 1896, E. Palmer, 

 no. 430A; Orosco, Jalisco, 1910, A. S. IJitchcock, no. 7,373; Quere- 

 taro, 1910, A. S. Hitchcock, no. 5,866; Valley of Mexico, 1901, C. G. 

 Pringle, nos. 8,572 & 9,606; Orizaba, Bottcri, no. 718. Guatemala: 

 Coban, Alta Verapaz, 1887, //. von Tuerclcheim, no. 1,287. Panama: 

 Chagres, 1850, A. Fendler, no. 365. 



Var. decipiens var. now, spiculis longioribus 3.5 mm. longis, 

 antheris longioribus 1 mm. longis. — Central Mexico: Etzatlan, 



