66 OUR NATIVE FERNS AND THEIR ALLIES. 



Sporangia with a rudimentary ring, opening longitudinally, in panicles. 



Family 4. OSMUNDACK^E, p. 77 

 Sporangia stalked, with a complete ring, opening transversely. 



Family 6. POLVPODIACEJE, p. 78, 

 6. Rooting in mud ; leaves filiform or quadrifoliate. 



Family 7. MARSILEACE^E, p. 123 

 Floating ; leaves spongy Family 8. SALVINIACE^E, p. 125 



Family I. OPHIOGLOSSACE^ Lindl. 



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

 sometimes bulbous root, straight or inclined in vernation. 

 Eusporangiate, the sporangia formed of the interior tissues, 

 variously clustered on sporophylls in the form of spikes or pani- 

 cles, destitute of a ring, opening by a transverse slit into two 

 valves and discharging their copious sulphur-yellow spores. 

 Prothallium (so far as known) subterranean, not green, monoe- 

 cious. The family contains about six genera, three of which are 

 represented in America. 



Our genera may be distinguished as follows : 



1. Sporangia in spikes cohering in two ranks 2 



Sporangia free, in compound spikes or panicles ; leaf mostly 



divided III. BOTRYCHIUM.- 



2. Spike solitary; leaf simple, entire, attached to the middle of 



the common stalk or below; terrestrial. I. OPHIOGLOSSUM. 



Spikes several, pendent from near the base of a palmately 



divided leaf ; epiphytic II. CHEIROGLOSSA. 



I. OPHIOGLOSSUM L. ADDSR-TONGUE. 

 Sporangia large, coriaceous, connate, coherent in two ranks 

 on the edges of a simple spike. Leaf simple, attached at the 

 middle of the main stalk or below, entire ; veins anastomosing. 

 Spores copious, sulphur-yellow. Terrestrial. Name from Gr. 

 o#zs, a serpent, and yXoaaa, a tongue. Includes twenty or 

 more species, six in our limits. 



* With several equal parallel "veins at the base of the leaf, the 

 mid-vein seldom branched hit anastomosing -with lateral -veinlets. 



\ Leaf ovate to elliptic, large ; basal -veins, 9 13 or more. 



i. O. vulgatum L. Rootstock cylindric, often large and 

 tuberous; leaf ovate to elliptic, often oblanceolate, i' 4' long; 



