BOTANY. 03 



which divides into four small spores, or sporulcs, the germinating bodies. 

 In some cases the operculum remains persistent, and the theca opens by 

 four valves. At the base of the theca there is occasionally a fleshy 

 protuberance at one side, called a struma : or a swelling of the seta, called 

 an apophysis. The calyptra is sometimes split on one side (dimidiate), at 

 'other times it is entire or split into short clefts all around its base 

 (mitriform). Between the teeth of the peristome and the edge of the theca 

 an elastic ring or annulus is formed, and occasionally a horizontal septum or 

 epiphragm extends across the mouth of the thecoe. The set« are sometimes 

 twisted, and so are the teeth of the peristome. Mosses are either erect or 

 creeping, terrestrial or aquatic plants, found in all moist countries, extending 

 from the Arctic to the Antarctic regions. They abound most in temperate 

 climates. They are among the first plants Avhich appear on newly formed 

 islands. 



Mosses have been divided into Pleurocarpi, those in which the fruit is 

 lateral, and Acrocarpi, whese the fruit is terminal. The principal North 

 American sub-orders are : Fo/ttinalecB, HypnacecB, Leskeacecü, Neckeracea., 

 Pterogonacea., BryacecB, Mecsiacecc, Bnrtrcmiiacece, Bu.vbaimiiacece, 

 Polt/trichacecB, FissidentefE, Leucobri/acecB, Dicranacecc, TricJiostoinacecc, 

 TctraphidecB, Orthotriceacefc^ EncalyptecB, Grimuiiacecc, Weissiacefc, 

 >Splachnace(v, Fiinariacea^ Pottiaceoi, Gi/mnostofnncea;, /^phagnacecc, 

 AndrceacecB, and PJiascacem. Illustrations of one or two species of these 

 sub-orders are furnished by our figures. PL 54, fig. 41, represents 

 Climacium dendroides, one of the Hypnaceaj found in woods on the 

 ground. Sphagnum acutifolium, or Peat-moss [fig. 39). This genus 

 furnishes most of the peat found in peat bogs, and employed for various 

 purposes. 



Order G. Lycopodiace.'k, the Club Moss Family. Stems creeping, or 

 corms ; annular vessels in the axis. Leaves imbricated, more or less 

 setaceous, sometimes subulate. ThecEe axillary and sessile, one to three 

 celled, opening by valves or indehiscent ; often of two kinds, one round, 

 reniform, or crescentic, containing minute powdery matter, and called by 

 some antheridia, though perhaps erroneously ; the other of a roundish tetra- 

 hedal form, inclosing a cell which produces four spores capable of germi- 

 nating ; the spores are considered by some as equivalent to ovules, and the 

 mother-cell as an ovary or oophoridium. In Isoctes, the two kinds of repro- 

 ductive bodies are imbedded in the substance of the base of the leaf. They 

 are moss-like plants, intermediate between ferns and mosses, and in some 

 respect allied to coniferous plants. They abound in Avarm, moist, insular cli- 

 mates. There are six genera, and about 200 species. Examples : Lycopo- 

 dium, Selaginclla, Isoetes. 



Some of the Lycopodiiwis arc emetic and cathartic. The powdery 

 matter in the thecfB is inflammable, and has been used as a substitute for 

 sulphur, under the name of Lycopode, or A^egetable brimstone. It is also 

 employed to cover pills, so as to prevent their being acted upon by 

 moisture. Lycopodium squamatum, a Brazilian, and L. lepidophyllum, a 

 Mexican species, coil up into a ball during the dry season, and unroll 



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