ncluded in that genus till their relation with _Melampsora_ was
clearly made out. The winter spores are in solid pulvinules, and their
fructification takes place towards the end of winter or in the spring.
This phenomenon consists in the production of cylindrical tubes,
which start from the upper extremity of the wedge-shaped spores, or
more rarely from the base. These tubes are straight or twisted, simple
or bifurcated, and each of them very soon emits four monosporous
spicules, at the same time that they become septate. The sporules are
in this instance globose.

[Illustration: FIG. 84.--Germinating pseudospore of _Uromyce
appendiculatus_. (Tulasne.)]

In _Uromyces_ germination follows precisely the same type as that of
the upper cell of _Puccinia_; in fact, Tulasne states that it is very
difficult to say in what they differ from the _Pucciniae_ which are
accidentally unilocular.

In _Cystopus_ a more complex method prevails, which will be examined
more closely hereafter.

In _Puccinia_, as already observed when describing their structure,
the pseudospores are two-celled. From the pores of each cell, which
are near the central septum, springs a clavate tube, which attains two
or three times the total length of the fruit, and of which the very
obtuse extremity curves more or less in the manner of a crozier.[G]
This tube, making a perfectly uncoloured transparent membrane, is
filled with a granular and very pale plastic matter at the expense
of the generative cell, which is soon rendered vacant; then it
gives rise to four spicules, usually on the same side, and at the
summit of these produces a reniform cellule. The four sporules so
engendered exhaust all the protoplasm at first contained in the
generative cell, so that their united capacity proves to be evidently
much insufficient to contain it, the more so as it leads to the
belief that this matter undergoes as it condenses an elaboration
which diminishes its size. In all cases the spicule originates
before the sporule which it carries, and also attains its full length
when the sporule appears. The form of the latter is at first
globular, then ellipsoid, and more or less curved. All these phases
of vegetation are accomplished in less than twelve hours, and if
the spore is mature and ready for germination, it is sufficient to
provoke it by keeping the pseudospores in a humid atmosphere.
During this process the two cells do not separate, nor does one
commence germ