of the Organs of Pilularia globulifera. 493 
the sporules of Jungermannia complanata exhibit similar lines after they have 
been submitted to the action of sulphuric acid. After the protrusion of the 
germ, however, it does appear to be quite immaterial from what part of the 
germ the first leaves, root or stem shall arise. 
It is almost superfluous to point out, that these primordial leaves, if the 
sporules be considered as seeds, have no analogy, except in their use, with 
cotyledons, because true cotyledons pre-exist in the seed, whereas these are 
the product of germination. But according to the view of the nature of 
sporules which I have endeavoured to establish, Pilularia must be considered 
as nearly allied to monocotyledons in its germination. In cotyledonous plants 
the first steps of germination (under which term I include the growth of the 
mature pollen) are protected by a distinct apparatus (the seed-coats) fur- 
nished for that purpose; and in monocotyledonous plants a single primordial 
leaf and root are developed in a sheath, through which they burst in the pro- 
gress of germination. Now Pilularia differs from this simply in not having 
the first stages of its germination protected by a separate apparatus, unless, 
indeed, the conical membranes which form the external cavity (Tas. XXXIV. 
fig. 6.) at the germinating end of the sporule are to be considered as the most 
rudimentary state of the female organ ; for, as in monocotyledons, the cellular 
mass arranges itself into a sheath, which incloses the rudiment of a leaf and 
root, and the amylaceous (?) particles and grumous fluid, which fill the cavity 
of the sporule, fulfil the same office as the albumen of monocotyledons. I shall 
conclude these observations by stating that I have not been able to detect 
any organs which, as in the Mosses, can by any possibility be supposed to 
perform the office of impregnating the sporules. 
Tintinhull, near Ilchester, 
Feb. 18, 1839. 
EXPLANATION OF THE PLATES. 
Tas. XXXIV. 
Fig. 1. A plant of Pilularia globulifera, of the natural size. 
Fig. 2. A mature involucrum, of the natural size, and in a dehiscent state. 
3T2 
