The reproduction of Fungi is accomplished not only by spores and conidia, but also sometimes by _chlamydospores_. These are fundaments[11] of sporangiophores and conidiophores, which have taken on a resting condition in the form of a spore, and are able to germinate and produce carpophores. In the formation of the chlamydospores the hyphæ accumulate reserve materials at the expense of the neighbouring cells; in the undivided hyphæ of the Phycomycetes transverse walls are formed, and finally the chlamydospores are set free by the decay of the empty cells connecting them with the mycelium. One must distinguish between _oidia_ and _true chlamydospores_. The former are more simple, the latter are a somewhat more differentiated form of carpophore fundaments, which serve for propagation in the same manner as spores. In _Chlamydomucor racemosus_ the chlamydospores grow out into the air and form differentiated carpophores. In the Autobasidiomycetes they only germinate vegetatively, and not with the formation of fructifications. From _Chlamydomucor_ up to the Autobasidiomycetes the successive development of the fructification, which is interrupted by the formation of the chlamydospores, degenerates more and more. Among certain Ustilagineæ the chlamydospores (brand-spores) no longer germinate with the production of fructifications. In the Uredinaceæ, only one of the three chlamydospore-forms has the property of producing fructifications on germination; the other forms only germinate vegetatively, like ordinary spores, and in the same manner as the chlamydospores of the Autobasidiomycetes. In the Hemibasidii, and the Uredinaceæ, in _Protomyces_, the chlamydospores are the chief means of reproduction. They are found also among the Ascomycetes. The sporangia and the conidia of the Fungi have their common origin in the sporangia of the Phycomycetes. The asci (and the Ascomycetes which are characterised by these bodies) are descended from the sporangia-forming, lower Fungi; the basidia (and the Basidiomycetes) from those which bear conidia. _The sporangia of the Phycomycetes are the primitive form and the starting point for all the reproductive forms of the Fungi._ The chlamydospores appear besides in all classes of Fungi as supplementary forms of reproduction, and are of no importance in determining relationships. Although the expression “fruit” must essentially be applied to true Phanerogams, yet, through usage, the term “_fruit-forms_,” is employed to designate the forms or means of reproduction of Fungi, and the organs of reproduction are known as _organs of fructification_, the sporangiophores and conidiophores as _fruit-bearers_ (_carpophores_), and the sporangiocarps, conidiocarps, and basidiocarps as “_fruit-bodies_.”