WOOTON AND STANDLEY FLORA OF NEW MEXICO. 29 



one kind of stem produced; branching above the base is rare except when the plant is 

 injured. Sometimes, though not frequently, it is somewhat branched from the base. 

 The rather delicate texture and the somewhat spreading, smooth-topped, long sheaths 

 tipped by a row of triangular black dots are characteristic. 



3. Equisetum hiemale L. Sp. PI. 1062. 1753. Scouring rush. 

 Type locality: "Habitat in Europse sylvis, asperis, uliginosis." 



Range: North America north of Mexico. 



New Mexico: Reserve; Gilmores Ranch; near Las Vegas, on the Gallinas River; 

 Rio Grande near Mesilla. 



This is a common rush along the streams and ditches. The form here referred to 

 is that spoken of as E. hiemale intermedium by Mr. A. A. Eaton. 



4. Equisetum. robustum A. Br. Amer. Journ. Sci. 46: 88. 1844. 

 Type locality: "Islands of the Mississippi River in Louisiana." 

 Range: New Jersey and Louisiana, westward across the continent. 



New Mexico: Tunitcha Mountains; Cedar Hill; Mesilla; Mogollon Mountains. 

 Wet ground, in the Lower Sonoran Zone. 



The large scouring rush occurs not uncommonly along the rivers and irrigating 

 ditches at the lower levels of the State. It may not be sufficiently distinct from 

 E. hiemale. 



Order 4. LYCOPODIALES. 



5. SELAGINELLACEAE. Selaginella Family. 



Mosslike terrestrial plants, usually only a few centimeters high; stems slender, 

 branching, erect or trailing; leaves small and scalelike, arranged in 4 to many rows; 

 sporangia 1-celled, globose, of two kinds, viz. , megasporangia bearing 4 megaspores 

 and microsporangia bearing many microspores, borne at the bases of the sporophylls, 

 these differing little from foliage leaves. 



1. SELAGINELLA Beauv. 



KEY TO THE SPECIES. 



Plants erect, tufted, with roots only on the lower part; leaves with 

 long terminal bristles and numerous marginal hairs on each 



side; plants grayish green 1. S. rupincola. 



Plantd more or less prostrate, forming mats, mostly rooting along 

 the stems; leaves various; plants grayish or bright green. 

 Stems very short, 6 cm. long or less; strobiles erect, 4-angled, 



usually longer than the vegetative branches 2. S. densa. 



Stems longer, 10 cm. or more; strobiles various. 



Megaspores irregularly wrinkled; strobiles erect; lea 



and short stems frequently much. crowded 3. S. v/rightii. 



Megaspores not wrinkled; strobiles hardly distinguish- 

 able from the vegetative parts. 

 Stems very slender, wiry, terete; leaves small, ap- 



] >r< iseed 4. S. hi in ica . 



Stems weaker; leaves lux, dark green 5. S. underwoodii. 



Selagiru lla I * pidophylla, the "resurrection plant," should be found in the Guadalupe 

 Mountains near the southern boundary, or in the limestone mountains of the Bouth- 

 v.i i corner. 



There is a single specimen of a species closely allied to S. arenicola Onderw. in 

 ill" National Herbarium, the label of which states thai it was collected al Lae \ 

 \>\ Plank. There is some uncertainty as i" whether the specimen is correctly labeled; 

 for this reason it is nol listed here. Collectors should look I Q that 



region and farther east and south. 



