128 OUR NATIVE FERNS AND THEIR ALLIES. 



of microspores. Named from Gr. a$eiv , to dry, and oX\vvai. 

 to destroy. Includes five species. 



i. A. Caroliniana Willd. Plant 4" 12" broad, much 

 branched ; leaves with ovate lobes, the lower reddish, the upper 

 green with a reddish border; macrospores with a minutely 

 granulate surface ; masses of microspores barbed at the tip. (A. 

 microphylla Kaulf., A. Mexicana Schlecht.) New York to 

 Florida, Arizona and Oregon. 



ORDER IV. OPHIOGLOSSACE^E Lindl. 



Plant-body consisting of stem and leaf, usually from a fleshy, 

 sometimes bulbous root, straight or inclined in vernation. 

 Sporangia formed of the interior tissue of the frond, spiked or 

 panicled, naked, not reticulated, destitute of a ring, opening by 

 a transverse slit into two valves discharging copious sulphur- 

 colored spores. Prothallium (so far as known) subterranean, 

 not green, monoecious. Contains, besides the two following 

 genera, Helminthostachys Kaulf., with a single old world species. 



I. Ophioglossum L. Sporangia cohering in one or more 

 simple spikes. Veins reticulate. 



II. Botrychium Swz. Sporangia in pinnate or compound 

 spikes or panicles. Veins free. 



I. OPHIOGLOSSUM L. ADDER-TONGUE. 

 Sporangia large, coriaceous, connate, coherent in two ranks 

 on the edges of a simple spike. Veins anastomosing. Spores 

 copious, sulphur-yellow. Name from Gr. ofiis, a serpent, and 

 yXoacra, a tongue. Includes ten species, four in our limits. 



i. EUOPHIOGLOSSUM. Fertile spike single, arising from the 

 base of the sterile segment. 



* Sterile portion near the middle of the stalk. 



1. O. vulgatum L. Rootstock short, oblique ; stalk 6' 12' 

 high, the sterile segment ovate or elliptical-oblong, i^' 4' long, 

 somewhat fleshy, somewhat narrowed at the base, sessile; fer- 

 tile spike i' or more long. (O. Engelmanni Prantl.) Maine to 

 Kentucky, Tennessee, Texas and Arizona to Alaska. 



** Sterile portion near the base of the stalks. 



2. O. qrotalophoroides Walt. Rootstock tuberous, 3" 5" 



