We began with the intention of monographing Chalara and very similar fungi (Excioconidium, etc.). We soon extended the scope of our study to encompass those dimorphic imperfect genera with Chalara-like phialides (Thielaviopsis, Chalaropsis, Stilbochalam, Hughesiella), then to cover two other genera with Chalara-like phialides but having characteristic ancillary sterile structures (Chaetochalara, Sporoschisma). Finally we considered several other genera with phialides having more or less cylindrical collarettes and deep-seated conidiogenous loci (Bloxamia, Endosporostilbe, Ascoconidium, Sporendocladia) or whose descriptions raised the suspicion that they had such attributes (Endoconidium, Columnophora, Milowia). To have extended the study further would have meant including phialidic genera which, although often having relatively deep collarettes, were otherwise not particularly morphologically comparable to Chalara (Catenularia, Phialophora, Phialocephala, Sporoschismopsis).

Our study, which began as an attempt to revise one genus, thus finished up by considering fifteen existing generic names (five reduced to synonymy, one to the status of nomen dubium) and adding one additional generic name (first published elsewhere).

Readers will find in the taxonomic part of this book a compilation of descriptions and illustrations of species of Sporoschisma and Fusichalara. Some may consider these redundant, especially since we have added nothing significantly new to what is already known about them: our purpose in including them is solely to bring together all taxonomic data relating to Chalara and other closely allied genera in a single source-book.