672 LYCOPODIACEJE. (CLUB-MOSS FAMILY.) 



* * Sterile portion of the frond long-petioled from near the base of the common stalk. 



5. B. lunarioides, Swartz. Sterile portion of the frond petioled from 

 near the base, 2 - 3-ternate, or the ultimate divisions often pinnate or pinnately 

 parted, broadly triangular in general outline ; the lobes or divisions obovate, 

 somewhat kidney-shaped, roundish or oblong, somewhat crenate; fertile stalk 

 3' -6' high; the fertile part mostly 2-pinnate. (Bdtrypus lunarioides, Michx. 

 Botrychium fumarioides, Willd.) Dry and rich woods, especially southward. 

 July. A state from Hingham, Massachusetts (C. J. Sprague), has the two 

 lateral primary divisions .of the sterile segment changed into long-stalked 

 fertile fronds. ' . 



Yar. obllquum (B. obliquum, Muhl.) is mostly larger (6' -17' high) ; the 

 fructification more compound ; the sterile segment with oblong or lanceolate 

 divisions, either obtuse or oblique at the base, nearly entire, toothed, or irregu- 

 larly pinnatifid. New England to "Wisconsin, and southward : rather scarce. 



Var. diss^Ctum (B. dissectum, Muhl.) has the divisions of the sterile 

 segment compoundly and laciniately cut into narrow small lobes and teeth : 

 otherwise as the last, into which it passes, and with which it grows. 



22. OPHIOGLOSSUM, L. ADDER'S-TONGUE. (PI. 19.) 



Mode of growth much as in Botrychium ; but the coriaceous sporangia con- 

 nate and coherent in two ranks on the edges of a simple spike, which in our 

 species is single and placed on a stalk rising from the base of the simple and 

 reticulated- veined sterile segment. Spores copious, sulphur-color. (Name 

 compounded of o^ts, a serpent, and y\><r<Ta, tongue.) 



1. O. VUlg&tlim, L. Sterile segment ovate or elliptical-oblong (2' -3' 

 long) rather fleshy, obtuse, narrowed at the base, and sessile near the middle 

 of the stalk of the fertile spike. Bogs and meadows : not common. July. 

 Stalk 6'- 12' high, rising from a short oblique rootstock, the bud not enclosed 

 in the base of the stalk. (Eu.) 



ORDER 131. LYCOPODIACE^E. (CLUB-Moss FAMILY.) 



Low plants, usually of Moss-like aspect ; with pretty large spore-cases 

 (sporangia or sporocarps) sessile in the axil of simple and sessile, persistent, 

 mostly awl-shaped or lanceolate leaves : of three genera, including the 

 aquatic and peculiar Isoetes. 



# Terrestrial, with erect or creeping stems : spore-cases free in the axils of the leaves. 



1. Lycopodiiim. Spore-cases all of one sort, coriaceous, mostly kidney-shaped, 2-valved, 



filled with innumerable minute spores. 



2. Selaginella. Spore-cases of two sorts ; one very small, oblong or globular, 2-valved, 



filled with innumerable minute spores j the other larger, 3 - 4-valved, containing 3 or 4 

 large spores. 



* * Aquatic, with a corm in place of stem, covered above with the dilated bases of the tufted 

 long and rush-like leaves, to which the spore-cases adhere. 



3. Isoetes. Spore-cases of two sorts ; one containing numerous large, the other numerous 



small spores. 



