554 
2. OpHiocLossumM ENGELMANNI Prantl. 
O. vulgatum Eaton, Ferns of the Southwest, U. S. Geol. 
Surv. 340. 1878. : 
QO. Engelmanni Prantl, Jahrb. d. K. Bot. Gart. Berlin, 3: 318. 
pl. 8. fig. 17. 1884. 
Plants 8-22 cm. high; rootstock cylindric with long brown 
roots, often bearing 2-3 fruiting and 1 sterile leaf on the same 
plant with the sheathing base of the old leaves frequently per- 
sistent ; petiole subterranean or partly exserted, 4-10 cm. long; 
sterile leaf elliptic or lanceolate-elliptic, obtuse but sharply apicu- 
late, 3-9 cm. long, 1.5-5 cm. broad; fleshy, becoming pellucid 
when old and dry, slightly paler beneath ; basal veins 13 or more, 
median one slightly stronger and unbranched below the middle of 
the frond, forking and anastomosing with the lateral ones above ; 
lateral inner veins parallel and approximate, outer ones arcuate- 
erect; transverse veinlets oblique and large, forming broad ob- 
long-hexagonal areas with numerous anastomosing or free vein- 
lets included; cells of the epidermis flexuous, much elongated in 
the middle beneath, stomata numerous; peduncle starting from 
the petiole or the base of the sterile lamina, 3-9 cm. long; spike 
1.5-2.5 cm. long, apiculate, sporangia 12-27 pairs; spores 
045-050 mm. in diameter, areolae 15-20, angular, striae not 
elevated. 
Easily distinguished from O.vualgatum by the apiculate sterile 
frond, its broad areolae with numerous anastomosing veinlets 
and its shorter peduncle. Type locality in damp sterile places in 
the higher valleys at Comanche Spring, Texas, Lindheimer, May, 
1849, no. 53. Also common on stony prairies, but very rare there 
with spikes; on rocks, in cedar woods near New Braunfels, 
Texas, Lindheimer, May, 1850, 414. It was distributed as O. vud- 
gatum var. in E. Hall's Plantae Texanae, from low grounds Hous- 
ton, April 16, 1871, no. 858. It had first been collected on arid 
rocks near the Mississippi at Jefferson Barracks, Missouri, by | 
Riehl, May, 1841, 242; Allenton, Mo., G. W. Letterman, 
June, 1875; Springfield, Mo., E. M. Sheperd, 1879; Rocky 
hillsides, Eggert, May 31, 1887; Independence, B. F. Bush, 
May, 1894; 813-822; Calcareous soil, Natchitoches, Louis- 
iana, April, Dr. Hale; wet and shady ground, 4500 ft. alt. 
Sanoita Valley, Arizona, Dr. Rothrock; on lime rocks, Tan- 
ner’s Canyon, Huachuca mountains, Arizona, J. G. Lemmon, 
August 29, 1882; damp places on mesas around Mustang moun-— : : 
