BOTANY. 63 
which divides into four small spores, or sporules, 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 thecz. The setze 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 which 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: Fontinalee, Hypnacee, Leskeacee, Neckeracee, 
Pterogonacee, Bryacee, Meesiacee, Bartraniacee, Buxrbaumiacea, 
Polytrichacee, Fissidentee, Leucobryacee, Dicranacee, Trichostomacee, 
Tetraphidee, Orthotriceacee, Encalyptee, Grimmiacee, Weissiacee, 
Splachnacee, Funariacee, Pottiacee, Gymnostomacee, Sphagnacee, 
Andreacee, and Phascacee. 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 Hypnacez 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. . 
OrveR 6. Lycopopiace#; the Club Moss Family. Stems creeping, or 
corms; annular vessels in the axis. Leaves imbricated, more or less 
setaceous, sometimes subulate. Thecez 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 4 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 Jsoetes, 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 warm, moist, insular cli- 
mates. There are six genera, and about 200 species. Examples: Lycopo- 
dium, Selaginella, Isoetes.  — 
Some of the Lycopodiwms are emetic and cathartic. The powdery 
matter in the thece is inflammable, and has been used as a substitute for 
sulphur, under the name of Lycopode, or vegetable 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 
63 
