

MOSSES: THEIR STRUCTURE AND CLASSIFICATION. fs G7 

as Cellulares; Phanerogamic plants being composed of various 
vascular tissues. There are, however, many exception to this rule, 
as in the vascular tissue of Ferns and Lycopods, and in the spiral 
cells and elators of Mosses and Hepaticze; and we find that the 
different parts of Nature are so intimately bound together, that it 
is impossible to give exact definitions, as in pure science, which, 
without exception, shall separate with accuracy any one family from 
another. 
Another feature of Cryptogams is their superficial development, 
the spores being free and placed at the end of threads or Mycelium. 
This definition must be taken in a very general manner, as there 
are many exceptions. 
The third, and perhaps the most important feature, is the absence 
of true pollen and seeds; for although they possess Antheridia 
and Archegonia corresponding to the Anthers and Pistils of 
Phenogams, their development arises from mere contact of the 
parts, and not by the extension of a thread piercing the ovule as in 
true pollen ; hence there is an absence of anything like a true 
embryo. 
Mosses and Hepaticee form the sub-kingdom Bryophyta, and 
are described by Berkeley as having spores numerous, never 
solitary, produced within variously formed capsuliform organs and 
giving rise after impregnation to an annual or perennial plant. 
Archegonia springing from the perfect plant and producing 
sporiferous fruit. 
I purposely omit saying anything further with regard to the 
development of the Moss, as I hope to explain this more fully in 
a subsequent paper, and shall refer only to so much as is necessary 
to explain its structure. 
In the male plant the leaves surrounding the Antheridia, or 
male inflorescence, constitute the Perigonium and are termed 
perigonial leaves ; while the cluster of leaves about the flask-shaped 
Archegonia, or female inflorescence, are called perichetial leaves, 
and constitute the Perichztium. Both Antheridia and Perigonia 
are mixed with jointed filaments called Paraphyses. 
Mosses are also generated by means of Gemmez: minute cellular 
ao found in the axils of the stem and on different parts of the 
eaf. 
_After impregnation the perfect Archegonium soon becomes 
distended by the enlargement of the embryonal cell, and is 
eventually torn asunder near the base; the upper portion being 
now termed the Calyptra, and the lower the Vaginula. 
_ The cell or vesicle is now converted into a fruit-stalk, or seta, 
and not until it has attained its full height does the apex swell and 
become a capsule. 
The capsule contains a central column, the Columella, round 

