those due to .Synchytrium, Protomyces, Cysto pus, many Ustilagineae, &c. These cases are not easily distinguished superficially froni the pustular outgrowth of actual mycelia and spores (stromata) of such Fungi as Nectria, Puccinia, &c. The cylindrical stem-swellings due to Calyptospora, Epichloe, &c., may also be mentioned here, and the tyro may easily confound with these the layers and cushions of eggs laid on similar organs by moths.