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Cryptogams or Flowerless Plants — Lycopodiacecz . 
Distribution. —A small Natural Order, represented in every quarter of the Globe. Two common 
British species, Stag’s-horn Moss (Lycopodium clavatum) and Fir Club-moss (L . Selago) y have a very 
wide distribution, occurring in both Hemispheres as well as south of the Equator. 
Number of British Genera, 2 ; Species, 8. 
Leaves linear or subulate, all similar and imbricate around the stem in British Club-mosses (Lycopodia); 
submerged, linear, quill-like and tufted in Quillwort (Isoetes lacustris); or of two kinds, membranous, very small and 
various in form, the larger distichously arranged in the plane of ramification, the smaller intermediate, appressed, 
and resembling stipules, as in Garden Selaginellas; minute, distantly scattered, and scale-like in the exotic genus 
Psilotum. 
SPORANGES i-celled; in Selaginella of two kinds, containing either macrospores or microspores; in Lycopodium 
but one kind has been discovered, containing microspores ; sporanges in Psilotum 3-celled ; in Quillwort of two 
kinds as in Selaginella, but divided by transverse partial or complete partitions into several cells. 
Reproduction not yet completely observed in Club-mosses ( Lycopodia); in Selaginella a narrow, scarcely- 
protruding, crescent-shaped prothallus is developed upon one side of the macrospores, bearing archegonia analogous 
to those on the prothallus of Ferns. The antheridia set free by the microspores under favourable conditions as to 
humidity and temperature resemble those of Ferns and Horsetails, and the archegonia are fertilised by their contact 
as in these groups. 
USES, &c.—The copious microspores of Stag’s-horn Moss are readily inflammable, and used to be collected 
for stage effect of lightning. A few species have an obscure medicinal value in their respective countries. Many 
species of Selaginella are cultivated in our greenhouses and for covering rockwork in Ferneries. 
Allied to Lycopodiaceae, though very different in habit, is the small Order Marsileace^e, represented in 
Britain by Pillwort ( Pilularia ), a low, grass-like, creeping aquatic with slender leaves circinately unfolding and 
bearing globose subsessile sporanges resembling grains of pepper. The sporanges are 4-celled, and each cell 
contains two kinds of spore, answering to the two kinds respectively in Quillwort and Selaginella. Pillwort is 
frequent, though easily overlooked, on the shallow margins of fresh-water pools in Britain. An Australian ally, 
with clover-like leaves (Marsilea salvatrix ), bears edible sporanges. 
