In _Ustilago (flosculorum)_ germination takes place readily in warm weather. The germ tube is rather smaller at its base than further on. In from fifteen to eighteen hours the contents become coarsely granular; at the same time little projections appear on the tube which are narrowed at the base, into which some of the protoplasm passes. These ultimately mature into sporules. At the same time a terminal sporule generally appears on the threads. Secondary sporules frequently grow from the primary, which are rather smaller, and these occasionally give rise to a third generation. In _Urocystis (pompholygodes)_ the germinating tubes spring exclusively from the darker central cells of the clusters. From these are developed at their extremity three or four linear bodies, as in _Tilletia_, but after this no further development has as yet been traced. It may be remarked here that Waldheim observed similar conjugation of the sporules in some species of _Ustilago_ as have been remarked in the sporules of the first generation in _Tilletia_. [Illustration: FIG. 90.--Pseudospore of _Ustilago receptaculorum_ in germination, and secondary spores in conjugation. (Tul.)] [Illustration: FIG. 91.--Conidia and zoospores of _Cystopus candidus_; _a._ conidium with the plasma divided; _b._ zoospores escaping; _c._ zoospores escaped from the conidium; _d._ active zoospores; _e._ zoospores, having lost their cilia, commencing to germinate.] Returning to _Cystopus_, as the last of the Uredines, we must briefly recapitulate the observations made by Professor de Bary,[K] who, by the bye, claims for them an affinity with _Peronospora_ (Mucedines but too well known in connection with the potato disease), and _not_ with the Uredines and their allies. In this genus there are two kinds of reproductive organs, those produced on the surface of the plant bursting through the cuticle in white pustules, and which De Bary terms _conidia_, which are generated in chains, and certain globose bodies termed _oogonia_, which are developed on the mycelium in the internal tissues of the foster plant. When the conidia are sown on water they rapidly absorb the moisture, and swell; the centre of one of the extremities soon becomes a large obtuse papilla resembling the neck of a bottle. This is filled with a granular protoplasm, in which vacuoles are formed. Soon, however, these vacuoles disappear, and very fine lines of demarcation separate the protoplasm into from five to eight polyhedric portions, each presenting a little faintly-coloured vacuole in the centre (_a_). Soon after this division the papilla at the extremity swells, opens itself, and at the same time the five to eight bodies which had formed in the interior are expelled one by one (_b_). These are zoospores, which at first take a lenticular form, and group themselves before the mouth of the parent cell in a globose mass (_c._) Very soon, however, they begin to move, and then vibratile