The germination in _Æcidium_ has been followed out by Tulasne,[F] either by placing the pseudospores in a drop of water, or confining them in a moist atmosphere, or by placing the leaves on which the _Æcidium_ flourishes upon water. The pseudospores plunged in water germinated more readily than the others. If the conditions were favourable, germination would take place in a few hours. _Æcidium Ranunculacearum_, D. C., on leaves of figwort, gives rarely more than one germinating filament, which soon attains three times the length of the diameter of the pseudospore. This filament generally remains simple, sometimes torulose, and distorted in a long spire. Sometimes it has been seen divided into two branches, nearly equal to each other. The spore in germinating empties itself of its plastic contents, contracts, and diminishes in size. The pseudospores of _Æcidium crassum_, P., emit three long filaments, which describe spirals, imitating the twistings of the stem of a bean or bindweed. In _Æcidium Violæ_, Schum, one filament is produced, which frequently rolls up its anterior extremity into a spire, but more often this same extremity rises in a large ovoid, irregular vesicle, which continues the axis of the filament, or makes with it a more or less decided angle. In whatever manner placed, this vesicle attracts to it all the orange protoplasm, and hardly does this become settled and complete before the vesicle becomes the starting point of a new development, for it begins to produce at its apex a filament, more slender than the previous one, stiff, and unbranched. [Illustration: FIG. 81.--Germination of _Æcidium Euphorbia (sylvaticæ)_, Tulasne.]