It must not be concluded, from the fact that we have not yet adverted to spermogones in connection with other fungi, that they are peculiar to the _Æcidiacei_. Such is by no means the case. As we have hereafter described other genera and species in which spermogones occur, it would be out of place to enter upon further details here. Let it suffice therefore that we state that they have been found in members of the genera, _Aregma_, _Triphragmium_, _Puccinia_, _Lecythea_, _Trichobasis_, and _Uredo_, but they have been found much more generally in _Rœstelia_ and _Æcidium_ than in any other genus. As comparatively little is yet known of these bodies, a fair field is open to the enterprising microscopist, with time at his disposal, and a good store of perseverance, to win for himself renown in the discovery of fresh facts, and the elucidation of some of the mysteries which yet enshroud these interesting organisms. From the foregoing pages he will learn the direction in which his researches should tend, and he may be assured that every new fact is of importance when carefully ascertained. [Illustration: Plate II. W. West imp. ] ------------------------------------------------------------------------ CHAPTER III. _DI-MORPHISM._ BEFORE entering further and more fully upon the subject of this volume, it may be advisable to attempt an explanation of a phenomenon of no uncommon occurrence in many groups of Fungi, and which is termed _di-morphism_.